Associations between urinary phenol and paraben concentrations and markers of oxidative stress and inflammation among pregnant women in Puerto Rico

Partial Effects in Environmental Mixtures: Evidence and Guidance on Methods and Implications

BACKGROUND

The effects of a mixture of exposures on health outcomes are of interest to public health but pose methodological hurdles. These exposures may impact the outcome in opposing ways, which we call the positive and negative partial effects of a mixture. There has been growing interest in estimating these partial effects and their ability to inform public health interventions.

OBJECTIVES

Methods like quantile g-computation (QGC) and weighted quantile sums regression (WQSr) were originally developed for estimating an overall mixture effect. These approaches, however, have not been comprehensively evaluated in their ability to estimate partial effects. We study the bias-variance tradeoffs of these approaches in estimating partial effects.

METHODS

We compare QGC with sample-splitting (QGCSS) and WQSr with sample-splitting (WQSSS) and new methods including a) QGC a priori (QGCAP) and WQS a priori (WQSAP), which use prior knowledge to determine the positive and negative exposures prior to partial effects estimation; b) model-averaging (QGC-MA); and c) elastic net to determine the split (QGC-Enet). We also considered WQSr with no sample-splitting (WQSNS), repeated holdout sets (RH-WQS), and two-index model with penalized weights (WQS2i). We compared performance under a) exposure correlations, b) varying sample sizes, c) spread in the negative effect across exposures, and d) imbalance in the partial effects.

RESULTS

Our simulation results showed that the estimation of negative and positive partial effects grows in root mean squared error and average bias as correlation among exposures increases, sample sizes shrink, the negative effect is spread over more exposures, or the imbalance between the negative and positive effects increases. Our results are demonstrated in two examples of mixtures in relation to oxidative stress biomarkers and telomere length.

DISCUSSION

Outside of having a priori knowledge, no method is optimally reliable for estimating partial effects across common exposure scenarios. We provide guidance for practitioners of when partial effects might be most accurately estimated under particular settings. https://doi.org/10.1289/EHP14942.

Periconception bisphenol and phthalate concentrations in women and men, time to pregnancy, and risk of miscarriage

BACKGROUND

Exposure to endocrine-disrupting chemicals such as bisphenols and phthalates might lead to adverse fertility and early pregnancy outcomes.

METHODS

This study was embedded in the Generation R Next Study, a population-based cohort study from preconception onwards. Urinary phthalate and bisphenol concentrations were assessed in the preconception period (938 women), defined as the period in which couples were actively trying to conceive, and early pregnancy (1,366 women and 1,202 men, mean gestational age at sampling 8·6 weeks). Time to pregnancy and miscarriage were assessed using questionnaires and ultrasounds. Subfertility was defined as the inability to conceive within 12 months or need for assisted reproductive technologies.

FINDINGS

Higher preconception urinary bisphenol S (BPS) and cyclohexane-1,2-dicarboxylic acid-monocarboxy isooctyl ester (mCOCH) concentrations in women were associated with longer time to pregnancy. Higher preconception mono-[(2-carboxymethyl)hexyl] phthalate, mono-2-ethyl-5-oxohexyl phthalate (mEOHP), mono-(7-carboxy-n-heptyl)phthalate (mCHpP), and mono benzyl phthalate (mBzBP) were associated with shorter time to pregnancy, and higher mono-2-ethyl-5-hydroxyhexyl phthalate (mEHHP), mEOHP, and mBzBP with lower odds of subfertility. In men, higher early pregnancy BPS, mCHpP, mono-4-methyl-7-hydroxyoctyl phthalate, mono-4-methyl-7-oxooctyl phthalate, and mono-ethyl phthalate were associated with shorter time to pregnancy or lower odds of subfertility. Higher preconception or early pregnancy BPS, phthalic acid, and mCHpP in women were associated with lower odds of miscarriage, whereas higher mono-carboxy-isoctyl phthalate, mCOCH, and mono-2-(propyl-6-carboxy-hexyl)-phthalate (cxmPHxP) with higher odds of miscarriage (all p-values <0·05).

INTERPRETATION

Preconception and early pregnancy exposure to bisphenols and phthalates may affect couple fertility. Our results should be considered as hypothesis generating and replicated in future studies, possibly including repeated chemical measurements and mixture analysis.

Parabens exposure and its impact on diabesity: A review

Parabens are a family of alkyl esters of 4-hydroxybenzoic acid. The most commonly used include methylparaben, ethylparaben, propylparaben, and butylparaben. These compounds have been reported to disrupt the endocrine system and are believed to affect the central nervous, immune, and reproductive systems, as well as lipid homeostasis, glucose levels, and thyroid function. Given these effects, parabens pose potential health risks, including their possible link to conditions like diabesity - a term describing the dual condition of type 2 diabetes mellitus and obesity. This review explores current literature on how parabens may influence key mechanisms in diabesity, such as gluconeogenesis, glycogenolysis, adipogenesis, insulin resistance, and inflammation. Understanding their role in these metabolic pathways is critical for assessing their contribution to the diabesity epidemic and guiding future research for minimizing their harmful health impacts.

Association between organic micropollutants in tap water and human exposure and birth outcomes: Implications for environmental health in northern Puerto Rico

The presence of micropollutants in Puerto Rico's tap water, potentially linked to nearby Superfund sites, was hypothesized to contribute to the region's higher preterm birth rate than the US mainland. This study analyzed the presence of 175 micropollutants in tap water samples collected from participant households and evaluated their association with human exposure using 14 oxidative stress and inflammation biomarkers in urine samples collected from pregnant participants, and further with the subsequent birth outcome information. Notably, three out of four oxidative stress biomarkers consistently showed negative correlations with five micropollutant categories, highlighting the oxidative stress induced by these contaminants. For the ten selected inflammation-related biomarkers, two showed positive yet not significant correlations with the five categories of micropollutants and, only one biomarker (MMP1), an inflammation biomarker whose down-regulation was associated with pre-mature birth implications, showed significant negative correlation with industrial chemicals and pesticides. Interestingly, the detected urinary phthalate metabolites in pregnant women could not be linked with the two parent phthalates found in the tap water, suggesting that the two phthalates in tap water may not be the primary source of phthalate exposure to human body. Furthermore, hormones in tap water showed significant moderate-to-strong negative correlations with birth outcomes, raising specific health concerns for pregnant women in northern Puerto Rico. This is the first study to investigate the association among a wider spectrum of tap water micropollutants with pregnancy exposure and birth outcome in Puerto Rico and provide insights into water quality and associated human health impacts.

Endocrine disrupting chemicals in early MS disease activity

BACKGROUND AND OBJECTIVES

Epidemiological data shows that the prevalence of multiple sclerosis (MS) and the female-to-male sex ratio among MS patients are increasing over time. Endocrine disrupting chemicals (EDCs) are ubiquitous and increasingly recognized for effects on estrogen signaling. This study aimed to determine whether there was an association between EDC levels and disease severity in newly diagnosed, female MS patients.

METHODS

This exploratory observational cohort study enrolled female patients, ages 18-60, via written informed consent from the Brigham MS Center. Enrollment criteria included diagnosis with MS within the past 5 years and completion of a questionnaire about potential EDC exposures. Exclusion criteria were intravenous steroids in the past 30 days. Collection processes and materials were designed to avoid EDC contamination. Urine samples were analyzed by NSF International (Ann Arbor, Michigan). Primary outcome measures were MRI parameters and clinical disease activity, including multivariable analysis adjusting for MS treatment types. Spearman correlation test was used for analysis and between group comparisons were conducted with one-way ANOVA.

RESULTS

68 patients with MS were enrolled. In the phthalates, mEOHP was negatively correlated with T2 lesion volume over time (R value = -0.522, p-value = 0.002, Bonferroni adjusted p = 0.03). For the phenols, triclocarban was negatively associated with cheese consumption (R value = -0.402, p = 0.001, Bonferroni adjusted p = 0.012) There was no association between EDCs and disease activity or demographic factors, nor significant correlation with exposure to household plastics.

CONCLUSION

This exploratory study identified a negative correlation between triclocarban and cheese consumption. Longitudinally, phthalate metabolite mEOHP was negatively correlated with T2 lesion volume over time. Exposure to EDCs may affect the early disease course in MS, and expansion of research efforts is warranted.

Association of environmental phenol and paraben exposure with allergic biomarkers in eczema: findings from NHANES 2005-2006

Endocrine-disrupting chemicals such as phenols and parabens can promote allergic conditions including eczema. We aimed to analyze the association between exposure to environmental phenols and parabens and allergic biomarkers-including total serum Immunoglobulin E (IgE), C-reactive protein (CRP), and eosinophils-in individuals with eczema, using the dataset from NHANES 2005-2006. This analysis was based on urinary biomarker levels of phenols and parabens, including bisphenol A, benzophenone-3, 4-tert-octylphenol, triclosan, as well as methyl, ethyl, propyl, and butyl parabens. The urinary biomarkers of phenols and parabens were quantified using online SPE-HPLC-MS/MS, while IgE, CRP, and eosinophil levels were analyzed using fluorescent-enzyme immunoassay, the ImmunoCAP 1000 system, latex-enhanced nephelometry, and the Beckman Coulter method, respectively. Following data extraction, we obtained 159 individuals with a history of eczema and categorized them by age for analysis. Our findings showed positive correlations between bisphenol A, triclosan, butyl paraben, methyl paraben, and propyl paraben and allergic biomarkers in children with eczema aged 6 to 8 years. Notably, a significant positive correlation was observed between methyl paraben exposure and IgE levels. In adults with eczema, 4-tert-octylphenol demonstrated a significant positive association with both IgE levels and eosinophil counts. These findings suggest that exposure to these chemicals may exacerbate eczema symptoms.

Examining the hidden dangers: Understanding how microplastics affect pregnancy

Microplastics, a fast-growing environmental concern, play a crucial role in developing the major pollution crisis that affects nearly the entire surface of the planet. Microplastics are tiny particles, measuring less than 5 mm which are ubiquitous, in occurrence, and found in a wide array of products including plastic packaging, synthetic textiles, seafood, fruits, vegetables, salt, sugar, bottled water, and even personal care products. The presence of microplastics in our environment and the potential adverse health effects they may cause have made them a significant perturbation in recent years. Pregnancy is a potentially life-changing experience that entails several apprehensions and new responsibilities for women. For expectant mothers, it is imperative to be aware of the implications of microplastics during pregnancy. One threatened concern is the potential transfer of microplastics across the placenta, which could expose the developing fetus to these particles. Although research on the impact of microplastics on pregnancy is still in its early stages, preliminary findings indicate potential risks that expectant mothers should be aware of. The timing of exposure during pregnancy may play a significant role in the potential risks associated with these tiny particles. In this review, we will delve into the topic, exploring how microplastics enter the body and the potential mechanism by which they pose risks to pregnancy outcomes.

Preconception exposure to bisphenol A and its alternatives: Effects on female fecundity mediated by oxidative stress and ovarian reserve

BACKGROUND

Various 'Bisphenol A (BPA)-free' alternatives have emerged in numerous personal products in recent years. However, it remains unclear whether BPA analogs affect female fecundity and possible biological mechanisms.

OBJECTIVES

We aimed to evaluate the relationships of bisphenol analogs with female fecundability and infertility and whether oxidative stress, inflammation, and ovarian reserve may play a mediation role in such associations.

METHODS

This prospective preconception cohort study included 957 couples who attempted pregnancy. BPA and six alternatives were measured in women's urine samples. Bisphenol analogs-outcome associations were estimated using discrete-time Cox hazards and logistic regression models. A quantile g-computation (QGC) methodology was further applied to assess the joint effects of co-exposure to bisphenol analogs on fecundity. We also quantified three biomarkers, including malondialdehyde (MDA), C-reactive protein and Anti-Müllerian hormone (AMH), to explore possible biological pathways.

RESULTS

Using an integrated analytical approach consisting of both single-pollutant and mixture models, we found that BPA and bisphenol AP (BPAP) were significantly associated with decreased fecundability (adjusted fecundability ratio (aFR) = 0.87, 95%CI: 0.81, 0.94 for BPA; aFR = 0.64, 95%CI: 0.48, 0.84 for BPAP) and increased risk of infertility (adjusted odd ratio (aOR) = 1.23, 95%CI: 1.06, 1.44 for BPA; aOR = 2.27, 95%CI: 1.29, 3.99 for BPAP) after controlling for other bisphenol analogs. The link between BPA and prolonged time to pregnancy was more prominent in overweight or obese women and those who had regular menstrual cycles. Bisphenol AF was associated with impaired fecundity in women aged 35 years or older. The mixed effects of bisphenol analogs on fecundity were statistically non-significant. Mediation analysis revealed a significant indirect effect of urinary MDA and serum AMH in bisphenol analogs-induced impaired fecundity, with all average causal mediation effects (ACME) showing statistical significance (PACME < 0.05).

CONCLUSIONS

Our prospective preconception cohort study suggests that BPA and BPAP may be associated with impaired female fecundity. Increased oxidative stress and decreased ovarian reserve may be the underlying pathways.

Long-term exposure to triclocarban induces splenic injuries in mice: Insights from spatial metabolomics and lipidomics

Triclocarban (TCC) is a widely used antimicrobial agent and known endocrine-disrupting chemical found in various products. While its potential toxicities on endocrine-related organs have been highlighted in previous studies, the effects of TCC on non-endocrine organs, particularly the spleen, remain largely unknown. Here, we employed a novel approach combining long-term TCC exposure in a mouse model with spatial metabolomics and lipidomics to investigate the effects of TCC on the spleen. Our results showed that TCC exposure significantly altered the splenic organ weight and coefficient and induced obvious pathological alterations. Omic analysis revealed that TCC exposure disrupted the splenic homeostasis, as indicated by the upregulation of glutathione metabolism, ceramide-to-sphingomyelin signaling and biosynthesis of glycerophospholipids. Notably, the data of mass spectrometry imaging (MSI) revealed that TCC accumulated in the red pulp of the mouse spleen, while its metabolites concentrated in the white pulp. Further MSI analyses identified region-specific metabolic disruptions, including upregulated ceramide signaling in the red pulp, indicating localized inflammation, and upregulated glutathione metabolism throughout the spleen, suggesting widespread oxidative damage. Our findings provide crucial insights into the spatial distribution and biochemical impact of TCC on mice spleens, highlighting the potential risks of long-term TCC exposure to immune function.

Relationships between bisphenol A and paraben exposure, oxidative stress, and the activity of outer hair cells in the cochlea in children with hearing loss

This study aimed to determine the associations of childhood exposure to bisphenol A (BPA) and parabens (PBs) with oxidative stress and the activity of outer hair cells (OHCs) in the cochlea of children with hearing loss (HL). A total of 641 children were enrolled in this cross-sectional study. Urinary concentrations of BPA and four PBs including methyl paraben (MP), ethyl paraben (EP), propyl paraben (PP), and butyl paraben (BP) were quantified by using liquid chromatography-tandem mass spectrometry (LC/MSMS). Four urinary biomarkers of oxidative stress, 8-hydroxy-2'-deoxyguanosine (8-OHdG), 8-nitroguanine (8-NO2Gua), 4-hydroxynonenal mercapturic acid (HNE-MA), and 8-isoprostaglandin F2α (8-iso-PGF2α), were measured using high-performance liquid chromatography-electrospray ionization mass spectrometry. Hearing tests were conducted by an audiologist in the audiometric test room, and the results were confirmed by an otolaryngologist. The activity of OHCs in the cochlea was measured by distortion product otoacoustic emissions (DPOAEs). The associations of BPA/PB exposure and oxidative stress with the activity of OHCs at different frequencies were evaluated in the multivariable linear regression models. There were 91 children with HL, for an incidence of approximately 14.2 %. There was a significant negative association between the presence of EP (1.5 K Hz, 3 K Hz) or PP (2 K Hz) or 8-OHdG (1 K Hz, 1.5 K Hz, 2 K Hz) and the activity of OHCs in the left ear. Significant results were also observed for BPA (2 K Hz), MP (1 K Hz, 1.5 K Hz, 2 K Hz), EP (3 K Hz), and 8-OHdG (2 K Hz) in the right ear. This study revealed that exposure to BPA/PBs reduces the activity of OHCs, especially at middle frequencies, in children.

Spatial metabolomics reveal metabolic alternations in the injured mice kidneys induced by triclocarban treatment

Triclocarban (TCC) is a common antimicrobial agent that has been widely used in medical care. Given the close association between TCC treatment and metabolic disorders, we assessed whether long-term treatment to TCC at a human-relevant concentration could induce nephrotoxicity by disrupting the metabolic levels in a mouse model. Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) was applied to investigate the alterations in the spatial distributions and abundances of TCC, endogenous and exogenous metabolites in the kidney after TCC treatment. The results showed that TCC treatment induced the changes in the organ weight, organ coefficient and histopathology of the mouse kidney. MSI data revealed that TCC accumulated in all regions of the kidney, while its five metabolites mainly distributed in the cortex regions. The abundances of 79 biomolecules associated with pathways of leukotriene E4 metabolism, biosynthesis and degradation of glycerophospholipids and glycerolipids, ceramide-to-sphingomyelin signaling were significantly altered in the kidney after TCC treatment. These biomolecules showed distinctive distributions in the kidney and displayed a favorable spatial correlation with the pathological damage. This work offers new insights into the related mechanisms of TCC-induced nephrotocicity and exhibits the potential of MALDI-MSI-based spatial metabolomics as a promising approach for the risk assessment of agents in medical care.

Systemic oxidative stress levels during the course of pregnancy: Associations with exposure to air pollutants

Increased systemic oxidative stress, implicated in adverse pregnancy outcomes for both mothers and fetuses, has been associated with gestational exposure to air pollutants such as polycyclic aromatic hydrocarbons (PAHs), fine particulate matter (PM2.5), and nitrogen dioxide (NO2). However, it is unclear whether exposure to pollutants at levels below the current air quality standards can increase oxidative stress in pregnant women. In a cohort of 305 pregnant persons residing in western New York, we examined the association between exposure to PM2.5, NO2, and PAHs (measured as urinary 1-hydroxypyrene) and urinary biomarkers of oxidative stress (malondialdehyde [MDA] and 8-hydroxy-2'-deoxyguanosine [8-OHdG]) measured in each trimester. After controlling for gestational stage, maternal age, lifestyles, and socioeconomic factors, each interquartile range (IQR) increase in 1-hydroxypyrene concentration (65.8 pg/ml) was associated with a 7.73% (95%CI: 3.18%,12.3%) higher in MDA levels throughout the pregnancy and in the first and second trimester. An IQR increase in PM2.5 concentration (3.20 μg/m3) was associated with increased MDA levels in the first trimester (8.19%, 95%CI: 0.28%,16.1%), but not the 2nd (-7.99%, 95% CI: 13.8%, -2.23%) or 3rd trimester (-2.81%, 95% CI: 10.0%, 4.38%). The average cumulative PM2.5 exposures in the 3-7 days before urine collection were associated with increased 8-OHdG levels during the second trimester, with the largest difference (22.6%; 95% CI: 3.46%, 41.7%) observed in relation to a one IQR increase in PM2.5 concentration in the previous 7 days. In contrast, neither oxidative stress biomarker was associated with NO2 exposure. Observed in pregnant women exposed to low-level air pollution, these findings expanded previously reported associations between systemic oxidative stress and high-level PM2.5 and PAH concentrations. Further, the first and second trimesters may be a susceptible window during pregnancy for oxidative stress responses to air pollution exposure.

Urinary paraben exposure increases the risk of a low estimated glomerular filtration rate in Taiwanese general population

BACKGROUND

The inconsistent relationship between chemical exposure and estimated glomerular filtration rate (eGFR) has been examined in only a few studies. We investigated the association between paraben exposure and indicators of renal function in a total of 361 individuals recruiting from a representative study.

METHOD

The levels of urinary parabens, including methylparaben (MeP), ethylparaben (EtP), propylparaben (PrP), and butylparaben (BuP), were measured using UPLC-MS/MS. The association between paraben exposure and indices of renal function was assessed using multiple logistic regression and Bayesian Kernel Machine Regression (BKMR).

RESULTS

The median levels of urinary parabens in the adult group were significantly higher than those in the minor group, that is, 397 vs. 148 ng/mL for MeP, 38.8 vs. 13.6 ng/mL for EtP, 117 vs. 57.7 ng/mL for PrP, and 6.61 vs. 2.79 ng/mL for BuP (all P < 0.001). In the adult group, multivariate regression models confirmed a positive association between the albumin-to-creatinine ratio and urinary MeP (β = 0.580) and a positive association of BUN (β = 0.061) and a negative association of eGFR (β = -0.051) with urinary EtP (all P < 0.001). In the adult group, compared with the lowest tertile group, the adjusted odds ratio in the third tertile (T3) of urinary EtP levels indicated a 3.08 times increased risk of eGFR abnormalities, followed by the second tertile (T2) with a 2.63 times increased risk. The generalized additive model (GAM) and BKMR models showed a non-linear correlation between urinary EtP levels and early CKD, as well as reduced eGFR. We observed a significant positive cumulative effect of urinary paraben on eGFR, and a significant positive single exposure effect of urinary EtP with eGFR abnormality.

CONCLUSION

We found a significant association between exposure to EtP and an increased risk of high BUN levels and decreased eGFR.

Comprehensive Serum Proteomic and Metabolomic Profiles of Pediatric Patients with Moyamoya Disease Reveal Core Pathways

Background

Moyamoya disease (MMD) signifies a cerebrovascular disorder with obscure origin and a more rapid and severe progression in children than adults. This investigation aims to uncover age-associated distinctions through proteomic and metabolomic profiling to gain insights into the underlying mechanisms of MMD.

Methods

Twelve MMD patients-six children and six adults-along with six healthy controls (HC), participated, each providing a 10 mL blood sample. Serum proteomic and metabolomic analyses were conducted using ultra-performance liquid chromatography and high-resolution mass spectrometry, complemented by bioinformatics to identify differential biomolecules and their interactions. Pathway implications were ascertained using GO and KEGG enrichment analysis.

Results

Notable proteomic and metabolomic discrepancies were observed between pediatric and adult MMD subjects. A total of 235 and 216 proteins varied in adult and pediatric cases compared to HCs, with 73 proteins shared. In addition, 129 and 74 anionic, plus 96 and 104 cationic metabolites, were differentially expressed in the pediatric and adult groups, respectively, with 34 anionic and 28 cationic metabolites in common. Age-specific biomolecules further characterized these distinctions. Enrichment analysis pinpointed immunity and inflammation pathways, with vitamin digestion and absorption highlighted as pivotal in pediatric MMD.

Conclusion

This study unveils distinct metabolic and proteomic patterns within pediatric and adult MMD patients. The critical role of the vitamin digestion and absorption pathway in the pathogenesis of pediatric MMD offers novel insight into disease mechanisms.

Urinary benzophenone-3 concentrations and ovarian reserve in a cohort of subfertile women

OBJECTIVE

To evaluate the association between the urinary benzophenone-3 concentrations and measures of ovarian reserve (OR) among women in the Environment and Reproductive Health study seeking fertility treatment at Massachusetts General Hospital (MGH) in Boston, Massachusetts.

DESIGN

Prospective cohort study.

SETTING

MGH infertility clinic in Boston, Massachusetts.

PATIENT(S)

Women in the Environment and Reproductive Health cohort seeking fertility treatment.

INTERVENTION(S)

Women contributed spot urine samples prior to assessment of OR outcomes that were analyzed for benzophenone-3 concentrations.

MAIN OUTCOME MEASURE(S)

Antral follicle count (AFC) and day 3 follicle-stimulating hormone (FSH) levels were evaluated as part of standard infertility workups during unstimulated menstrual cycles. Quasi-Poisson and linear regression models were used to evaluate the association of the specific gravity-adjusted urinary benzophenone-3 concentrations with AFC and FSH, with adjustment for age and physical activity. In the secondary analyses, models were stratified by age.

RESULT(S)

This study included 142 women (mean age ± standard deviation, 36.1 ± 4.6 years; range, 22-45 years) enrolled between 2009 and 2017 with both urinary benzophenone-3 and AFC measurements and 57 women with benzophenone-3 and FSH measurements. Most women were White (78%) and highly educated (49% with a graduate degree). Women contributed a mean of 2.7 urine samples (range, 1-10), with 37% contributing ≥2 samples. Benzophenone-3 was detected in 98% of samples. The geometric mean specific gravity-corrected urinary benzophenone-3 concentration was 85.9 μg/L (geometric standard deviation, 6.2). There were no associations of benzophenone-3 with AFC and day 3 FSH in the full cohort. In stratified models, a 1-unit increase in the log geometric mean benzophenone-3 concentration was associated with a 0.91 (95% confidence interval, 0.86-0.97) times lower AFC among women aged ≤35 years and an increase in the FSH concentration of 0.73 (95% confidence interval, 0.12-1.34) IU/L among women aged >35 years.

CONCLUSION(S)

In the main models, urinary benzophenone-3 was not associated with OR. However, younger patients may be vulnerable to the potential effects of benzophenone-3 on AFC. Further research is warranted.

Human exposure characteristics of pharmaceutical and personal care product chemicals and associations with dietary habits

Considering the widespread presence of pharmaceutical and personal care products (PPCPs) in the environment and their adverse health effects, human exposure to PPCPs has caused worldwide concern. However, there remains insufficient information on the exposure assessment of the Chinese population. Based on this, the exposure levels of 13 PPCPs in the urine samples of 986 Chinese adults were measured, aiming to provide information on the prevalence of PPCP occurrence and investigate potential correlations between PPCP exposure and obesity. Results showed that the detection rates of these compounds in urine ranged from 28.12 % to 98.58 %, with median concentrations ranging below the limit of detection to 10.58 ng mL-1. Methyl-paraben (MeP) was the most dominant paraben and had the highest urinary concentration (median = 10.12 ng mL-1), while 4-hydroxy-benzophenone (4-OH-BP) was the dominant benzophenone derivative (median = 0.22 ng mL-1). In antibacterials, the urinary concentration of triclosan (mean = 42.00 ng mL-1) was much higher than that of triclocarban (mean = 0.63 ng mL-1). PPCP concentrations were significantly associated with sex, age, body mass index, education level, and annual household income (p < 0.050). Regression analysis of dietary habits showed that seafood and tea consumption may be significant exposure sources of PPCP exposure (p < 0.050). Furthermore, individual exposure to MeP (odds ratio (OR) < 1, p = 0.002) and 4-OH-BP (OR < 1, p = 0.009) exhibited a significantly negative association with obesity in females. Also, analysis results from quantile g-computation and Bayesian kernel machine regression models demonstrated that an inverse correlation between PPCP mixture exposure and obesity was significant in females. This study reports the extensive prevalence of PPCP exposure among adults from China, and may provide crucial insights into PPCP exposure dynamics. More epidemiological studies are need in the future, with a thorough knowledge of PPCP exposure.

Sex-Specific and Trimester-Specific Associations of Prenatal Exposure to Bisphenols, Parabens, and Triclosan with Neonatal Birth Size and Gestational Age

Bisphenols, parabens, and triclosan (TCS) are common endocrine disrupters used in various consumer products. These chemicals have been shown to cross the placental barrier and affect intrauterine development of fetuses. In this study, we quantified serum levels of six bisphenols, five parabens, and TCS in 483 pregnant women from southern China. Quantile-based g-computation showed that combined exposure to bisphenols, parabens, and TCS was significantly (p < 0.05) and negatively associated with birth weight (β = -39.9, 95% CI: -73.8, -6.1), birth length (β = -0.19, 95% CI: -0.34, -0.04), head circumference (β = -0.13, 95% CI: -0.24, -0.02), and thoracic circumference (β = -0.16, 95% CI: -0.29, -0.04). An inverse correlation was also identified between mixture exposure and gestational age (β = -0.12, 95% CI: -0.24, -0.01). Bisphenol A (BPA), bisphenol Z (BPZ), bisphenol AP (BPAP), propylparaben (PrP), and TCS served as the dominant contributors to the overall effect. In subgroup analyses, male newborns were more susceptible to mixture exposure than females, whereas the exposure-outcome link was prominent among pregnant women in the first and second trimesters. More evidence is warranted to elucidate the impacts of exposure to mixtures on birth outcomes, as well as the underlying mechanisms.

Association of Phenols, Parabens, and Their Mixture with Maternal Blood Pressure Measurements in the PROTECT Cohort

BACKGROUND

Phenols and parabens are two classes of high production volume chemicals that are used widely in consumer and personal care products and have been associated with reproductive harm and pregnancy complications, such as preeclampsia and gestational diabetes. However, studies examining their influence on maternal blood pressure and gestational hypertension are limited.

OBJECTIVES

We investigated associations between individual phenols, parabens, and their mixture on maternal blood pressure measurements, including systolic and diastolic blood pressure (SBP and DBP) and hypertension during pregnancy (defined as stage 1 or 2 hypertension), among N = 1,433 Puerto Rico PROTECT study participants.

METHODS

We examined these relationships cross-sectionally at two time points during pregnancy (16-20 and 24-28 wks gestation) and longitudinally using linear mixed models (LMMs). Finally, we used quantile g-computation to examine the mixture effect on continuous (SBP, DBP) and binary (hypertension during pregnancy) blood pressure outcomes.

RESULTS

We observed a trend of higher odds of hypertension during pregnancy with exposure to multiple analytes and the overall mixture [including bisphenol A (BPA), bisphenol S (BPS), triclocarbon (TCC), triclosan (TCS), benzophenone-3 (BP-3), 2,4-dichlorophenol (2,4-DCP), 2,5-dichlorophenol (2,5-DCP), methyl paraben (M-PB), propyl paraben (P-PB), butyl paraben (B-PB), and ethyl paraben (E-PB)], especially at 24-28 wk gestation, with an adjusted mixture odds ratio ( OR ) = 1.57 (95% CI: 1.03, 2.38). Lower SBP and higher DBP were also associated with individual analytes, with results from LMMs most consistent for methyl paraben (M-PB) or propyl paraben (P-PB) and increased DBP across pregnancy [adjusted M-PB β = 0.78 (95% CI: 0.17, 1.38) and adjusted P-PB β = 0.85 (95% CI: 0.19, 1.51)] and for BPA, which was associated with decreased SBP (adjusted β = - 0.57 ; 95% CI: - 1.09 , - 0.05 ). Consistent with other literature, we also found evidence of effect modification by fetal sex, with a strong inverse association observed between the overall exposure mixture and SBP at visit 1 among participants carrying female fetuses only.

CONCLUSIONS

Our findings indicate that phenol and paraben exposure may collectively increase the risk of stage 1 or 2 hypertension during pregnancy, which has important implications for fetal and maternal health. https://doi.org/10.1289/EHP14008.

Application of the Key Characteristics of Carcinogens to Bisphenol A

The ten key characteristics (KCs) of carcinogens are based on characteristics of known human carcinogens and encompass many types of endpoints. We propose that an objective review of the large amount of cancer mechanistic evidence for the chemical bisphenol A (BPA) can be achieved through use of these KCs. A search on metabolic and mechanistic data relevant to the carcinogenicity of BPA was conducted and web-based software tools were used to screen and organize the results. We applied the KCs to systematically identify, organize, and summarize mechanistic information for BPA, and to bring relevant carcinogenic mechanisms into focus. For some KCs with very large data sets, we utilized reviews focused on specific endpoints. Over 3000 studies for BPA from various data streams (exposed humans, animals, in vitro and cell-free systems) were identified. Mechanistic data relevant to each of the ten KCs were identified, with receptor-mediated effects, epigenetic alterations, oxidative stress, and cell proliferation being especially data rich. Reactive and bioactive metabolites are also associated with a number of KCs. This review demonstrates how the KCs can be applied to evaluate mechanistic data, especially for data-rich chemicals. While individual entities may have different approaches for the incorporation of mechanistic data in cancer hazard identification, the KCs provide a practical framework for conducting an objective examination of the available mechanistic data without a priori assumptions on mode of action. This analysis of the mechanistic data available for BPA suggests multiple and inter-connected mechanisms through which this chemical can act.

Urinary phenol and paraben concentrations in association with markers of inflammation during pregnancy in Puerto Rico

Exposure to phenols and parabens may contribute to increased maternal inflammation and adverse birth outcomes, but these effects are not well-studied in humans. This study aimed to investigate relationships between concentrations of 8 phenols and 4 parabens with 6 inflammatory biomarkers (C-reactive protein (CRP); matrix metalloproteinases (MMP) 1, 2, and 9; intercellular adhesion molecule-1 (ICAM-1); and vascular cell adhesion molecule-1 (VCAM-1)) measured at two time points in pregnancy in the PROTECT birth cohort in Puerto Rico. Linear mixed models were used, adjusting for covariates of interest. Results are expressed as the percent change in outcome per interquartile range (IQR) increase in exposure. Particularly among phenols, numerous significant negative associations were found, for example, between benzophenone-3 and CRP (-11.21 %, 95 % CI: -17.82, -4.07) and triclocarban and MMP2 (-9.87 %, 95 % CI: -14.05, -5.5). However, significant positive associations were also detected, for instance, between bisphenol-A (BPA) and CRP (9.77 %, 95 % CI: 0.67, 19.68) and methyl-paraben and MMP1 (10.78 %, 95 % CI: 2.17, 20.11). Significant interactions with female fetal sex and the later study visit (at 24-28 weeks gestation) showed more positive associations compared to male fetal sex and the earlier study visit (16-20 weeks gestation). Our results suggest that phenols and parabens may disrupt inflammatory processes pertaining to uterine remodeling and endothelial function, with important implications for pregnancy outcomes. More research is needed to further understand maternal inflammatory status in an effort to improve reproductive and developmental outcomes.

Endocrine-disrupting compounds and their impact on human placental function: evidence from placenta organ-on-chip studies

The effects of endocrine-disrupting compounds (EDCs) on the placenta, a critical gestational organ for xenobiotic protection, are well reported; however, models to determine the role of EDCs in placental disruption are limited. An advanced 2nd-trimester human placenta organ-on-chip model (2TPLA-OOC) was developed and validated, with six representative cells of the maternal and the fetal interface interconnected with microchannels. Various EDCs (150 ng mL-1 each of bisphenol A, bisphenol S, and polybrominated diphenyl ethers-47 and -99) were gradually propagated across the chip for 72 hours, and their various effects were determined. Cigarette smoke extract (CSE), an environmental risk factor, was used as a positive control. EDCs produced overall oxidative stress in the placental/decidual cells, induced cell-specific endocrine effects, caused limited (<10%) apoptosis/necrosis in trophoblasts and mesenchymal cells, induced localized inflammation but an overall anti-inflammatory shift, did not change immune cell migration from stroma to decidua, and did not affect placental nutrient transport. Overall, (1) the humanized 2TPLA-OOC recreated the placental organ and generated data distinct from the trophoblast and other cells studied in isolation, and (2) at doses associated with adverse pregnancies, EDCs produced limited and localized insults, and the whole organ compensated for the exposure.

Distribution of parabens and 4-HB in human blood

Human blood has been commonly and routinely analyzed to determine internal human exposure to parabens. However, data on the occurrence of parabens and their common metabolite, p-hydroxybenzoic acid (4-HB), in different human blood matrixes is still limited. In this study, 139 pairs of serum and whole blood samples were collected from Chinese adults, and then analyzed them for 5 parabens and 4-HB. Methylparaben (MeP) and propylparaben (PrP) were consistently the predominant parabens in human serum (mean 2.3 and 2.1 ng/mL, respectively) and whole blood (1.9 and 1.3 ng/mL, respectively). Mean concentrations of 4-HB in human serum and whole blood were 7.7 and 12 ng/mL, respectively. Concentrations of parabens, except benzylparaben (BzP), and 4-HB in human serum were significantly (p < 0.01) correlated with that in whole blood. Distribution pattern of parabens and 4-HB in human blood was evaluated, for the first time, based on their partitioning between human serum and whole blood (Kp). Mean Kp values of parabens, except BzP, increased with the alkyl chain length from 0.83 to 1.6. BzP (mean 1.4) had a comparable mean Kp value to PrP (mean 1.4). Among target analytes, 4-HB had the lowest mean Kp value (0.75). These data are important to select appropriate blood matrixes for conducting human exposure assessment and epidemiological studies on parabens.

Urinary biomarkers of exposure to organophosphate, pyrethroid, neonicotinoid insecticides and oxidative stress: A repeated measurement analysis among pregnant women

Exposure to insecticides may be associated with increased oxidative stress (OS), but few studies have assessed the associations of OS biomarkers (OSBs) with exposure to multiple insecticides and their mixture, especially in pregnant women who are a vulnerable population. In the present study, 1,094 Chinese pregnant women were recruited and a total of 3,282 urine samples were collected at their three trimesters to measure eight metabolites of organophosphates, three metabolites of pyrethroids, nine typical neonicotinoids/their metabolites, and three OSBs of DNA damage (8-OHdG), RNA damage (8-OHG), and lipid peroxidation (HNE-MA). Among the twenty target insecticide metabolites, sixteen of them were frequently detected; thirteen of them were detected in over 86% of all the urine samples except for imidacloprid (IMI, detection frequency: 72.9%), desnitro-imidacloprid (DN-IMI, 70.0%), and clothianidin (CLO, 79.6%). The reproducibility of their concentrations across the three trimesters was poor to fair (intraclass correlation coefficients <0.50). Multiparity and warm season were related to higher urinary levels of some insecticide metabolites, while higher education level and inadequate weight gain during pregnancy were significantly associated with lower concentrations of certain insecticide metabolites. Linear mixed model analyses suggested that almost all the frequently detected insecticide metabolites [other than 3-phenoxybenzoic acid (3-PBA)] were significantly associated with elevated levels of the three OSBs (8-OHdG, 8-OHG, and HNE-MA), where the percent change (Δ%) ranged 8.10-36.0% for 8-OHdG, 8.49-34.7% for 8-OHG, and 5.92-182% for HNE-MA, respectively, with each interquartile ratio (IQR)-fold increase in the concentrations of the individual exposure biomarkers. Weighted quantile sum models demonstrated that the insecticide metabolite mixture was positively associated with the three OSBs. Overall, urinary desmethyl-clothianidin (DM-CLO) and 3,5,6-trichloro-2-pyridinol (TCPy) were the top insecticide exposure biomarkers contributing to the association with 8-OHdG and 8-OHG levels, while PNP contributed the most to the association with HNE-MA levels. These findings suggested that gestational exposure to organophosphates, pyrethroids, neonicotinoids, their transformation products, and their mixture may increase oxidative damage to lipids, RNA, and DNA during pregnancy.

Urinary phenols and parabens exposure in relation to urinary incontinence in the US population

BACKGROUND

Our study aimed to investigate the impact of urinary concentrations of personal care products (PCPs)-related phenols (PNs) and parabens (PBs), including Triclosan (TCS), Bisphenol A (BPA), Benzophenone-3 (BP-3), Butylparaben (BPB), Ethylparaben (EPB), Methylparaben (MPB), and Propylparaben (PPB), on urinary incontinence (UI) occurrence.

METHOD

We conducted a cross-sectional analysis using data from the National Health and Nutrition Examination Survey (NHANES) spanning the years 2007 to 2016. Regression analysis was employed to investigate the relationship between exposure to PCPs-related substances, various levels of exposure, and UI within both the general population and the female demographic. Additionally, the Bayesian Kernel Machine Regression (BKMR) model was used to assess the effects of mixtures on UI.

RESULTS

Our analysis comprised 7,690 participants who self-reported their diagnosis. Among them, 12.80% experienced stress urinary incontinence (SUI), 11.80% reported urge urinary incontinence (UUI), and 10.22% exhibited mixed urinary incontinence (MUI). In our fully adjusted multivariable models, BP-3 exposure exhibited a positive association with SUI (OR 1.07, 95% CI 1.02-1.14, p = 0.045). BPA exposure correlated with an increased risk of UUI (OR 1.21, 95% CI 1.01-1.44, p = 0.046) and MUI (OR 1.26, 95% CI 1.02-1.54, p = 0.029). TCS exposure displayed a negative correlation with the incidence of MUI (OR 0.87, 95% CI 0.79-0.97, p = 0.009). No significant links were observed between parabens and urinary incontinence. Notably, among the female population, our investigation revealed that BPA exposure heightened the risk of MUI (OR 1.28, 95% CI 1.01-1.63, p = 0.043). Participants in the highest tertile of BP-3 exposure demonstrated elevated likelihoods of SUI and MUI compared to those in the lowest tertile. In the BKMR analysis, negative trends were observed between the mixture and the risks of UUI and MUI when the mixture ranged from the 25th to the 40th and 35th to the 40th percentiles or above, respectively. Additionally, a positive trend was identified between the mixture and MUI when it was in the 40th to 55th percentile.

CONCLUSION

In conclusion, our findings suggest that exposure to BPA, TCS, and BP-3 may contribute to the development of urinary incontinence.

Repeated measurements and mixture effects of urinary bisphenols, parabens, polycyclic aromatic hydrocarbons, and other chemicals on biomarkers of oxidative stress in pre- and postpartum women

The association between oxidative stress and exposure to bisphenols, parabens, phenols, polycyclic aromatic hydrocarbons (PAH), and volatile organic compounds (VOCs) has been investigated by many in vitro and in vivo studies. However, most of these findings are based on cross-sectional studies, as a result of which the combined effects of these compounds have been rarely analyzed. In this study, our objective was to assess urinary bisphenols, parabens, PAHs, and VOCs, in relation to oxidative stress during pre-and postpartum periods, analyze the association between these chemicals and oxidative stress via repeated measurements using a linear mixed model (LMM), and evaluate the combined effects exerted by these chemicals on oxidative stress using Bayesian Kernel Machine Regression (BKMR). A total 529 urine samples were collected from 242 pregnant women during the 1st and 2nd trimesters, as well as postpartum follow-ups. Three bisphenols, four parabens, benzopheone-3 (BP-3), triclosan (TCS), four PAHs, two VOCs, and 3- phenoxy-benzoic acid (3-PBA) were analyzed. We also measured 8-hydroxydeoxyguanosine (8-OHdG) and malondialdehyde (MDA), which serve as oxidative stress biomarkers in maternal urine samples. During this period, 8-OHdG decreased steadily, whereas MDA increased during pregnancy and decreased after childbirth. LMM indicated that Bisphenol A, Prophyl-paraben, BP-3, and 1-hydroxypyrene (1-OHP) showed a significant association with increased MDA levels. The BKMR models revealed that the mixture effect exerted by these 16 chemicals had changed MDA levels, which indicate oxidative stress, and that both Butyl Paraben (BP) and 1-hydroxypyrene (1-OHP) had contributed to such oxidative stress. Mixtures of each subgroup (bisphenols, parabens, and PAHs) were associated with increased MDA levels. These findings suggest that exposure to some phenols and PAHs during pre- and post-partum stages may cause oxidative stress, and that exposure to these chemicals should be minimized during this period.

Exposure to biocides and its association with atopic dermatitis among children and adolescents: A population-based cross-sectional study in South Korea

BACKGROUND

Biocides have emerged as a contributor to the rising cases of atopic dermatitis among children and adolescents. Previous animal studies suggested that phenols, parabens, and pyrethroid insecticides present in these products might play a role in atopic dermatitis. However, there's limited epidemiological evidence confirming the individual or combined effects of exposure to these chemicals on atopic dermatitis in young populations. This study aimed to investigate the association between phenol, paraben, and pyrethroid metabolite levels in urine and atopic dermatitis among Korean children and adolescents METHODS: We analyzed 556 preschool children (3-5 years), 701 schoolchildren (6-11 years), and 731 adolescents (12-17 years) enrolled in the 4th Korean National Environmental Health Survey (KoNEHS) (2018-2020). We used logistic regression and Bayesian kernel machine regression to evaluate the association between atopic dermatitis and individual or mixed exposure to urinary triclosan (TCS), parabens (methylparaben, ethylparaben, propylparaben, and butylparaben), and 3-phenoxybenzoic acid (3-PBA) levels.

RESULTS

Urinary TCS levels were positively associated with atopic dermatitis in schoolchildren. When stratified by sex, male schoolchildren exhibited an increasing prevalence of atopic dermatitis as their urinary TCS and 3-PBA levels increased. The combined effect of biocide mixtures on atopic dermatitis was also significantly increased in male schoolchildren, with TCS as the main contributor.

CONCLUSIONS

These study findings suggest that biocides at levels found in Korean children and adolescents affect atopic dermatitis.

Relationship between exposure to parabens and benzophenones and prostate cancer risk in the EPIC-Spain cohort

The etiology of prostate cancer is not fully elucidated. Among environmental risk factors, endocrine-disrupting chemicals (EDCs) deserve special mention, as they alter metabolic pathways involved in hormone-dependent cancers. Epidemiological evidence assessing the carcinogenicity of EDCs is scarce. The aim of this study was to analyze the relationship between exposure to parabens and benzophenones and prostate cancer risk. We conducted a case-cohort study nested within the EPIC-Spain prospective multi-center cohort. Study population comprised 1,838 sub-cohort participants and 467 non-sub-cohort prostate cancer cases. Serum concentrations of four parabens and two benzophenones were assessed at recruitment. Covariates included age, physical activity, tobacco smoking, alcohol consumption, body mass index, educational level and diabetes. Borgan II weighted Cox proportional hazard models stratified by study center were applied. Median follow-up time was 18.6 years (range = 1.0-21.7 years). Most sub-cohort participants reached primary education at most (65.5%), were overweight (57.7%) and had a low level of physical activity (51.3%). Detection percentages varied widely, being lowest for butyl-paraben (11.3%) and highest for methyl-paraben (80.7%), which also showed the highest geometric mean (0.95 ng/ml). Cases showed significantly higher concentrations of methyl-paraben (p = 0.041) and propyl-paraben (p < 0.001). In the multivariable analysis, methyl-paraben - log-transformed (HR = 1.07; 95%CI = 1.01-1.12) and categorized into tertiles (HR = 1.60 for T3; 95%CI = 1.16-2.20) -, butyl-paraben - linear (HR = 1.19; 95%CI = 1.14-1.23) and log-transformed (HR = 1.17; 95%CI = 1.01-1.35) - and total parabens - log-transformed (HR = 1.09; 95%CI = 1.02-1.17) and categorized into tertiles (HR = 1.62 for T3; 95%CI = 1.10-2.40) - were associated with an increased prostate cancer risk. In this study, higher concentrations of methyl-, butyl-, and total parabens were positively associated with prostate cancer risk. Further research is warranted to confirm these findings.

Expression Profiles of Genes Related to Development and Progression of Endometriosis and Their Association with Paraben and Benzophenone Exposure

Increasing evidence has been published over recent years on the implication of endocrine-disrupting chemicals (EDCs), including parabens and benzophenones in the pathogenesis and pathophysiology of endometriosis. However, to the best of our knowledge, no study has been published on the ways in which exposure to EDCs might affect cell-signaling pathways related to endometriosis. We aimed to describe the endometriotic tissue expression profile of a panel of 23 genes related to crucial cell-signaling pathways for the development and progression of endometriosis (cell adhesion, invasion/migration, inflammation, angiogenesis, and cell proliferation/hormone stimulation) and explore its relationship with the exposure of patients to parabens (PBs) and benzophenones (BPs). This cross-sectional study included a subsample of 33 women with endometriosis from the EndEA study, measuring their endometriotic tissue expressions of 23 genes, while urinary concentrations of methyl-, ethyl-, propyl-, butyl-paraben, benzophenone-1, benzophenone-3, and 4-hydroxybenzophenone were determined in 22 women. Spearman's correlations test and linear and logistic regression analyses were performed. The expression of 52.2% of studied genes was observed in >75% of endometriotic tissue samples and the expression of 17.4% (n = 4) of them in 50-75%. Exposure to certain PB and BP congeners was positively associated with the expression of key genes for the development and proliferation of endometriosis. Genes related to the development and progression of endometriosis were expressed in most endometriotic tissue samples studied, suggesting that exposure of women to PBs and BPs may be associated with the altered expression profile of genes related to cellular pathways involved in the development of endometriosis.

Developmental programming: Impact of preconceptional and gestational exposure to a real-life environmental chemical mixture on maternal steroid, cytokine and oxidative stress milieus in sheep

BACKGROUND

Gestational exposure to environmental chemicals (ECs) is associated with adverse, sex-specific offspring health effects of global concern. As the maternal steroid, cytokine and oxidative stress milieus can have critical effects on pregnancy outcomes and the programming of diseases in offspring, it is important to study the impact of real-life EC exposure, i.e., chronic low levels of mixtures of ECs on these milieus. Sheep exposed to biosolids, derived from human waste, is an impactful model representing the ECs humans are exposed to in real-life. Offspring of sheep grazed on biosolids-treated pasture are characterized by reproductive and metabolic disruptions.

OBJECTIVE

To determine if biosolids exposure disrupts the maternal steroid, cytokine and oxidative stress milieus, in a fetal sex-specific manner.

METHODS

Ewes were maintained before mating and through gestation on pastures fertilized with biosolids (BTP), or inorganic fertilizer (Control). From maternal plasma collected mid-gestation, 19 steroids, 14 cytokines, 6 oxidative stress markers were quantified. Unpaired t-test and ANOVA were used to test for differences between control and BTP groups (n = 15/group) and between groups based on fetal sex, respectively. Correlation between the different markers was assessed by Spearman correlation.

RESULTS

Concentrations of the mineralocorticoids - deoxycorticosterone, corticosterone, the glucocorticoids - deoxycortisol, cortisol, cortisone, the sex steroids - androstenedione, dehydroepiandrosterone, 16-OH-progesterone and reactive oxygen metabolites were higher in the BTP ewes compared to Controls, while the proinflammatory cytokines IL-1β and IL-17A and anti-inflammatory IL-36RA were decreased in the BTP group. BTP ewes with a female fetus had lower levels of IP-10.

DISCUSSION

These findings suggest that pre-conceptional and gestational exposure to ECs in biosolids increases steroids, reactive oxygen metabolites and disrupts cytokines in maternal circulation, likely contributors to the aberrant phenotypic outcomes seen in offspring of BTP sheep - a translationally relevant precocial model.

Exposure to Butylparaben Induces Craniofacial Bone Developmental Toxicity in Zebrafish (Danio rerio) Embryos

Butylparaben (BuP) is a common antibacterial preservative utilized extensively in food, medical supplies, cosmetics, and personal care products. The current study reports the use of Zebrafish (Danio rerio) embryos to investigate potential developmental toxicity caused by exposure to BuP. The development of Neural crest cells (NCCs) is highly active during gastrulation in Zebrafish embryos. Thus, we utilized 0.5 mg/L, 0.75 mg/L, and 1 mg/L BuP solutions, respectively, in accordance with the international safety standard dosage. We observed severe craniofacial cartilage deformities, periocular edema, cardiac dysplasia, and delayed otolith development in the Zebrafish larvae 5 days after exposure. The oxidative stress response was significantly enhanced. In addition, the biochemical analysis revealed that the activities of catalase (CAT) and superoxide dismutase (SOD) were significantly reduced relative to the control group, whereas the concentration of malondialdehyde (MDA) was significantly elevated. Furthermore, ALP activity, a marker of osteoblast activity, was also reduced. Moreover, the RT-qPCR results indicated that the expression of chondrocyte marker genes sox9a, sox9b, and col2a1a was down-regulated. In addition, the morphology of maxillofacial chondrocytes was altered in Zebrafish larvae, and the proliferation of cranial NCCs was inhibited. Accordingly, our findings indicate that strong oxidative stress induced by BuP inhibits the proliferation of NCCs in larval Zebrafish, leading to craniofacial deformities.

Occurrence of bisphenol diglycidyl ethers and bisphenol analogs, and their associations with DNA oxidative damage in pregnant women

Bisphenol diglycidyl ethers (BDGEs) and Bisphenol A and its analogs (bisphenols) may have the same exposure routes and coexposure phenomenon in sensitive populations such as pregnant women. Previous biomonitoring studies on BDGEs are limited. Levels of fifteen bisphenols, six BDGEs and the DNA oxidative damage biomarker 8-hydroxy-2-deoxyguanosine (8-OHdG) were measured in the urine of pregnant women recruited in south China (n = 358). We aimed to provide the occurrence of bisphenols and BDGEs in pregnant women, and to investigate the potential relationship between their exposure and oxidative stress. Bisphenol A, bisphenol S, bisphenol F, bisphenol AP and all BDGEs (except for BADGE·2HCl) were frequently detected. The total concentrations of all bisphenols and BDGEs were 0.402-338 and 0.104-32.5 ng/mL, with geometric means of 2.87 and 2.48 ng/mL, respectively. BFDGE was the most abundant chemical of BDGEs, with a median concentration of 0.872 ng/mL, followed by BADGE·H2O·HCl (0.297 ng/mL). Except for pre-pregnancy obesity, maternal age/height, employment, fasting in the morning and parity did not affect the urinary concentrations of BDGEs. Significant and weak correlations were observed between concentrations (unadjusted) of total bisphenols and BDGEs (r = 0.389, p < 0.01), indicating their similar sources and exposure routes. The biomarker 8-OHdG was detected in all samples, with concentrations ranging from 1.98 to 32.6 ng/mL (median: 9.96 ng/mL). Levels of 8-OHdG were positively correlated with urinary several bisphenol concentrations (adjusted β range: 0.037-0.089, p < 0.05) but were not correlated with those of BDGEs. Further studies should focus on whether BDGEs and bisphenols exert combined effects on oxidative stress. Our study provided the first BDGEs exposure data in pregnant women and indicated that BDGEs exposure was highly prevalent in pregnant women as early as 2015 in south China.

Human Exposure to Bisphenols, Parabens, and Benzophenones, and Its Relationship with the Inflammatory Response: A Systematic Review

Bisphenols, parabens (PBs), and benzophenones (BPs) are widely used environmental chemicals that have been linked to several adverse health effects due to their endocrine disrupting properties. However, the cellular pathways through which these chemicals lead to adverse outcomes in humans are still unclear, suggesting some evidence that inflammation might play a key role. Thus, the aim of this study was to summarize the current evidence on the relationship between human exposure to these chemicals and levels of inflammatory biomarkers. A systematic review of peer-reviewed original research studies published up to February 2023 was conducted using the MEDLINE, Web of Science, and Scopus databases. A total of 20 articles met the inclusion/exclusion criteria. Most of the reviewed studies reported significant associations between any of the selected chemicals (mainly bisphenol A) and some pro-inflammatory biomarkers (including C-reactive protein and interleukin 6, among others). Taken together, this systematic review has identified consistent positive associations between human exposure to some chemicals and levels of pro-inflammatory biomarkers, with very few studies exploring the associations between PBs and/or BPs and inflammation. Therefore, a larger number of studies are required to get a better understanding on the mechanisms of action underlying bisphenols, PBs, and BPs and the critical role that inflammation could play.

Environmental phenol exposure associates with urine metabolome alteration in young Northeast Indian females

Urinary biomonitoring delivers the most accurate environmental phenols exposure assessment. However, environmental phenol exposure-related biomarkers are required to improve risk assessment to understand the internal processes perturbed, which may link exposure to specific health outcomes. This study aimed to investigate the association between environmental phenols exposure and the metabolome of young adult females from India. Urinary metabolomics was performed using liquid chromatography-mass spectrometry. Environmental phenols-related metabolic biomarkers were investigated by comparing the low and high exposure of environmental phenols. Seven potential biomarkers, namely histidine, cysteine-s-sulfate, 12-KETE, malonic acid, p-hydroxybenzoic acid, PE (36:2), and PS (36:0), were identified, revealing that environmental phenol exposure altered the metabolic pathways such as histidine metabolism, beta-Alanine metabolism, glycerophospholipid metabolism, and other pathways. This study also conceived an innovative strategy for the early prediction of diseases by combining urinary metabolomics with machine learning (ML) algorithms. The differential metabolites predictive accuracy by ML models was >80%. This is the first mass spectrometry-based metabolomics study on young adult females from India with environmental phenols exposure. The study is valuable in demonstrating multiple urine metabolic changes linked to environmental phenol exposure and a better understanding of the mechanisms behind environmental phenol-induced effects in young female adults.

Benzophenone-3: Comprehensive review of the toxicological and human evidence with meta-analysis of human biomonitoring studies

BACKGROUND

Benzophenone-3 (BP-3) and its major metabolite benzophenone-1 (BP-1) are widely used as UV filters in sunscreens and cosmetics to prevent sunburn and skin damage, or as stabilizers to prevent photodegradation in many commercial products. As a result, their presence is ubiquitous in the environment, wildlife and humans. Based on endocrine disruption concerns, international regulatory agencies are performing a closer evaluation.

OBJECTIVE AND METHODS

This work aimed to comprehensively review the available human relevant evidence for safety issues in MEDLINE/PubMed in order to create a structured database of studies, as well as to conduct an integrative analysis as part of the Human Biomonitoring for Europe (HBM4EU) Initiative.

RESULTS

A total of 1,635 titles and abstracts were screened and 254 references were evaluated and tabulated in detail, and classified in different categories: i) exposure sources and predictors; ii) human biomonitoring (HBM) exposure levels to perform a meta-analysis; iii) toxicokinetic data in both experimental animals and humans; iv) in vitro and in vivo rodent toxicity studies; and v) human data on effect biomarkers and health outcomes. Our integrative analysis showed that internal peak BP-3 concentrations achieved after a single whole-body application of a commercially available sunscreen (4% w/w) may overlap with concentrations eliciting endocrine disrupting effects in vitro, and with internal concentrations causing in vivo adverse female reproductive effects in rodents that were supported by still limited human data. The adverse effects in rodents included prolonged estrous cycle, altered uterine estrogen receptor gene expression, endometrium hyperplasia and altered proliferation and histology of the mammary gland, while human data indicated menstrual cycle hormonal alterations and increased risk of uterine fibroids and endometriosis. Among the modes of action reported (estrogenic, anti-androgenic, thyroid, etc.), BP-3 and especially BP-1 showed estrogenic activity at human-relevant concentrations, in agreement with the observed alterations in female reproductive endpoints. The meta-analysis of HBM studies identified a higher concern for North Americans, showing urinary BP-3 concentrations on average 10 and 20 times higher than European and Asian populations, respectively.

DISCUSSION AND CONCLUSIONS

Our work supports that these benzophenones present endocrine disrupting properties, endorsing recent European regulatory efforts to limit human exposure. The reproducible and comprehensive database generated may constitute a point of departure in future risk assessments to support regulatory initiatives. Meanwhile, individuals should not refrain from sunscreen use. Commercially available formulations using inorganic UV filters that are practically not absorbed into systemic circulation may be recommended to susceptible populations.

Exposure to endocrine-disrupting chemicals and risk of gestational hypertension and preeclampsia: A systematic review and meta-analysis

Prenatal exposure to endocrine-disrupting chemicals has been linked to gestational hypertension (GH) and preeclampsia (PE). However, the results were conflicting and inconclusive. We conducted a systematic review and meta-analysis for an overview of these relationships. We searched PubMed, and Google Scholar for studies investigating bisphenol A, phthalates, and per or poly-fluoroalkyl substances and GH or PE. Pooled odds ratio (OR) with a 95% confidence interval (CI) were calculated for risk estimate using the generic inverse variance method. A total of 14 studies were included in the present analysis. The pooled results demonstrated that perfluorooctanoic acid (PFOA, OR:1.20, 95% CI: 1.04, 1.39), perfluoro octane sulfonic acid (PFOS, (OR:1.23, 95% CI: 1.10, 1.38), and perfluononanoic acid (PFNA, OR:1.20, 95% CI: 1.03, 1.40) were significantly associated with an increased risk of PE. There was no significant association observed with perfluoro hexane sulfonic acid (PFHxS), perfluoro decanoic acid (PFDA), perfluoro heptanoic acid (PFHpA), and perfluoro undecanoic acid (PFUnDA) and PE. For GH, a statistically significant positive association was found with PFOA (OR:1.18, 95% CI: 1.01, 1.39) and PFHxS (OR:1.15, 95% CI: 1.02, 1.29). Among various phthalates analysed only mono-ethyl phthalate (MEP, OR:1.37, 95% CI: 1.11, 1.70) showed an association with GH. From our analysis, bisphenol A exposure during pregnancy did not show a significant association with the risk of PE. Our findings indicated that exposure to PFASs such as PFOA, PFOS, and PFNA during pregnancy is associated with an increased risk of PE and PFOA and PFHxS with GH. We also found that MEP was associated with GH. Most of the results were unstable in sensitivity analysis. Since most of these associations have limited evidence, more research is needed to confirm these findings.

Variability, determinants, and associations with oxidative stress biomarkers of pentachlorophenol among Chinese pregnant women: A longitudinal study

Pentachlorophenol (PCP) is ubiquitous and moderately persistent in the environment, and it is an identified human carcinogen. Previous animal experiments indicate that toxic mechanisms of PCP include oxidative stress. However, no epidemiological study has reported the association between PCP exposure and oxidative stress; such association in pregnant women, a vulnerable population, is of particular interest. This study aimed to characterize PCP concentrations in 2304 urine samples from 768 pregnant women, explore its determinants, and evaluate the associations between PCP exposure and three oxidative stress biomarkers across three trimesters. The median concentrations of PCP (100% detected) in the first, second, and third trimester were 0.61, 0.59, and 0.48 ng/mL, respectively, with a significant decrease trend. The intraclass correlation coefficient of specific gravity (SG)-adjusted PCP was 0.26, indicating high variability for PCP across the three trimesters. PCP concentrations were significantly higher in older, pre-pregnancy overweight, multiparous, high-income, and employed women during pregnancy. Urinary PCP was markedly lower in samples collected during spring compared to other seasons. Linear mixed effect models for repeated measures revealed that ln-transformed SG-adjusted PCP was significantly associated with increased 8-hydroxy-2'-deoxyguanosine (8-OHdG; percent change [%Δ] caused by each interquartile range increase of PCP: 46.2, 95% confidence interval [CI]: 40.2, 52.5) and 8-hydroxyguanosine (8-OHG;%Δ [95% CI]: 44.8 [40.1, 49.8]), but the positive association with 4-hydroxy2-nonenal-mercapturic acid (HNE-MA) was not significant. PCP was also positively associated with increased 8-OHdG and 8-OHG in each trimester using general linear models, and its associations with HNE-MA were only significant at T1 (%Δ [95% CI]: 19.1 [1.05, 40.3]) and T2 (%Δ [95% CI]: 12.6 [0.32, 26.3]). Our findings provide valuable information about PCP exposure characteristics during pregnancy and the potential effects of PCP exposure on oxidative stress in pregnant women.

Triclosan is associated with breast cancer via oxidative stress and relative telomere length

Introduction

Triclosan (TCS), a widely prescribed broad-spectrum antibacterial agent, is an endocrine-disrupting chemical. The relationship and biological mechanisms between TCS exposure and breast cancer (BC) are disputed. We aimed to examine the correlation between urinary TCS exposure and BC risk and estimated the mediating effects of oxidative stress and relative telomere length (RTL) in the above association.

Methods

This case-control study included 302 BC patients and 302 healthy individuals in Wuhan, China. We detected urinary TCS, three common oxidative stress biomarkers [8-hydroxy-2-deoxyguanosine (8-OHdG), 8-iso-prostaglandin F_2α (8-isoPGF_2α), 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA)], and RTL in peripheral blood mononuclear cells.

Results

Significant associations were observed between log-transformed urinary concentrations of TCS, 8-OHdG, HNE-MA, 8-isoPGF_2α, RTL, and BC risk, with the odds ratios (95% confidence intervals) being 1.58 (1.32-1.91), 3.08 (1.55-6.23), 3.39 (2.45-4.77), 3.99 (2.48-6.54), and 1.67 (1.35-2.09), respectively. Continuous TCS exposure was significantly positively correlated with RTL, HNE-MA, and 8-isoPGF_2α (all p<0.05) but not with 8-OHdG (p = 0.060) after adjusting for covariates. The mediated proportions of 8-isoPGF2_2α and RTL in the relationship between TCS and BC risk were 12.84% and 8.95%, respectively (all p<0.001).

Discussion

In conclusion, our study provides epidemiological evidence to confirmed the deleterious effects of TCS on BC and indicated the mediating effect of oxidative stress and RTL on the correlation between TCS and BC risk. Moreover, exploring the contribution of TCS to BC can clarify the biological mechanisms of TCS exposure, provide new clues for the pathogenesis of BC, which is of great significance to improving public health systems.

Human serum paraben levels and their associations with rheumatoid arthritis: a case-control study from Hangzhou, China

Parabens are widely used in consumer products resulting in frequent exposure to humans. To date, little is known about the association between human paraben exposure and rheumatoid arthritis (RA). In this study, a case-control study (n = 290) was conducted in Hangzhou, China, aiming to quantify the concentrations of methyl paraben (MeP), ethyl paraben (EtP), propyl paraben (PrP), and butyl paraben (BuP) in serum samples and to determine their associations with RA risks. MeP (mean 4.7 ng/mL, range <0.05-20 ng/mL) was the predominant paraben in human serum, followed by PrP (1.9 ng/mL, <0.12-24 ng/mL), EtP (1.4 ng/mL, <0.09-10 ng/mL), and BuP (1.09 ng/mL, <0.10-10 ng/mL). With 1-unit increase of MeP concentrations in human serum, the levels of rheumatoid factors, anticyclic citrullinated peptide antibody, and immunoglobulin G will increase by 0.19 unit (95% confidence intervals [CI]: 0.12-0.46), 0.30 unit (95% CI: 0.26-0.58), and 0.24 unit (95% CI: 0.21-0.30) in the adjusted model, respectively. One-unit increase of MeP and PrP concentrations in human serum was associated with an increase of 0.15 (95% CI: 0.037-0.28) and 0.20 (95% CI: 0.10-0.32) in the C-reactive protein concentrations. In addition, an association between serum MeP levels and the incidence of RA (odds ratios (OR)_crude = 1.33, CI: 1.11-1.62, p = 0.03; OR_adjusted = 1.86, CI: 1.32-2.63, p = 0.02) was positive and significant. Based on the measurements of serum paraben concentrations, this work supports the evidence for the significant associations among paraben exposure, change of specific immune marker, and RA risks.

Urinary paracetamol (4-acetaminophenol) and its isomer 2-acetaminophenol of Chinese pregnant women: Exposure characteristics and association with oxidative stress biomarkers

N-Acetyl-4-aminophenol (NA4AP, paracetamol/acetaminophen), a widely used pharmaceutical, is ubiquitous in urine samples of general population, raising concern about human health risks; oxidative stress is considered to be a mechanism for its toxicities. N-Acetyl-2-aminophenol (NA2AP) is an isomer of NA4AP; until now, few studies characterized exposure characteristics of NA4AP and NA2AP in pregnant women. In this work, NA4AP and NA2AP concentrations in urine samples (n = 2124) collected at three different trimesters were measured to examine their internal body burden among Chinese pregnant women (n = 708) and their associations with three oxidative stress biomarkers (OSBs, 8-OHG, 8-OHdG, and HNE-MA). NA4AP was detected in 100% of the urine samples (median concentration: 7.96 ng/mL); NA2AP was detected in 94.9% of them (median: 3.05 ng/mL). The intraclass correlation coefficients of their concentrations across three trimesters were poor (<0.4); correlations of NA4AP and NA2AP were weak (r: 0.15-0.23). Pregnant women who had higher household income or urine samples provided in summer (vs. winter) had higher concentrations of NA4AP. Pregnant women who had a college degree or above (vs. less than a high school education) had higher concentrations of NA2AP but urine samples provided in summer (vs. winter) had lower concentrations of NA2AP. The 95th percentile estimated daily intake of NA4AP (2,331 ng/kg-bw/d) based on averaged concentrations of the three trimesters was 40 times lower than the cRfD for NA4AP (2.33 vs. 93 μg/kg-bw/d). Urinary concentrations of NA4AP and NA2AP were associated with higher levels of the selected OSBs. For example, an interquartile range increase in NA4AP was associated with a 26.5% (95% CI: 23.6-29.6%) increase in 8-OHG, a 27.5% (95% CI: 23.8-31.3%) increase in 8-OHdG, and a 33.4% (95% CI: 24.7-42.7%) increase in HNE-MA (p < 0.05). This is the first study to measure their concentrations repeatedly over three trimesters, examine their exposure characteristics, and reveal their associations with the selected OSBs in pregnant women. Further studies are needed to identify non-intentional exposure sources of NA4AP, NA2AP, and another isomer of them (i.e., N-acetyl-3-aminophenol), as well as more health risks related to their exposure.

Urinary Phenols in Early to Midpregnancy and Risk of Gestational Diabetes Mellitus: A Longitudinal Study in a Multiracial Cohort

Environmental phenols are ubiquitous endocrine disruptors and putatively diabetogenic. However, data during pregnancy are scant. We investigated the prospective associations between pregnancy phenol concentrations and gestational diabetes mellitus (GDM) risk. In a nested matched case-control study of 111 individuals with GDM and 222 individuals without GDM within the prospective PETALS cohort, urinary bisphenol A (BPA), BPA substitutes (bisphenol F and bisphenol S [BPS]), benzophenone-3, and triclosan were quantified during the first and second trimesters. Cumulative concentrations across the two times were calculated using the area under the curve (AUC). Multivariable conditional logistic regression examined the association of individual phenols with GDM risk. We conducted mixture analysis using Bayesian kernel machine regression. We a priori examined effect modification by Asian/Pacific Islander (A/PI) race/ethnicity resulting from the case-control matching and highest GDM prevalence among A/PIs. Overall, first-trimester urinary BPS was positively associated with increased risk of GDM (adjusted odds ratio comparing highest vs. lowest tertile [aORT3 vs. T1] 2.12 [95% CI 1.00-4.50]). We identified associations among non-A/Ps, who had higher phenol concentrations than A/PIs. Among non-A/PIs, first-trimester BPA, BPS, and triclosan were positively associated with GDM risk (aORT3 vs. T1 2.91 [95% CI 1.05-8.02], 4.60 [1.55-13.70], and 2.88 [1.11-7.45], respectively). Triclosan in the second trimester and AUC were positively associated with GDM risk among non-A/PIs (P < 0.05). In mixture analysis, triclosan was significantly associated with GDM risk. Urinary BPS among all and BPA, BPS, and triclosan among non-A/PIs were associated with GDM risk. Pregnant individuals should be aware of these phenols' potential adverse health effects.

Inflammation and oxidative stress as mediators of the impacts of environmental exposures on human pregnancy: Evidence from oxylipins

Inflammation and oxidative stress play major roles in healthy and pathological pregnancy. Environmental exposure to chemical pollutants may adversely affect maternal and fetal health in pregnancy by dysregulating these critical underlying processes of inflammation and oxidative stress. Oxylipins are bioactive lipids that play a major role in regulating inflammation and increasing lines of evidence point towards an importance in pregnancy. The biosynthetic production of oxylipins requires oxygenation of polyunsaturated fatty acids, which can occur through several well-characterized enzymatic and nonenzymatic pathways. This review describes the state of the science of epidemiologic evidence on oxylipin production in pregnancy and its association with 1) key pregnancy outcomes and 2) environmental exposures. We searched PubMed for studies of pregnancy that measured one or more oxylipin analytes during pregnancy or delivery. We evaluated oxylipin associations with three categories of adverse pregnancy outcomes, including preeclampsia, preterm birth, and fetal growth restriction, along with several categories of environmental pollutants. The majority of studies evaluated one to two oxylipins, most of which focused on oxylipins produced from nonenzymatic processes of oxidative stress. However, an increasing number of recent studies have leveraged technological advancements to profile a large number of oxylipins produced from distinct biosynthetic pathways. Although the literature indicated robust evidence that oxylipins produced via nonenzymatic pathways are associated with pregnancy outcomes and environmental exposures, evidence for enzymatically produced oxylipins showed that associations may differ between biosynthetic pathways. Along with summarizing this evidence, we review promising therapeutic options to regulate oxylipin production and provide a set of recommendations for future epidemiologic studies in these research areas. Further evidence is needed to improve our understanding of how oxylipins may act as key biological mediators for the adverse effects of environmental pollutants on pregnancy outcomes.

Comprehensive assessment of estrogenic activities of parabens by in silico approach and in vitro assays

Parabens are ubiquitous pollutants in the environment and humans due to their wide applications in food, pharmaceuticals, and personal care products. Although the estrogenic activity of some parabens has been confirmed, the underlying mechanisms and the structure-estrogenic activity relationship are still largely unclear. Here, we systematically used in silico and in vitro approaches to investigate the estrogenic potency of typical parabens, including methyl-, ethyl-, propyl-, iso-propyl-, butyl-, iso-butyl- and benzyl-paraben. Molecular dynamics simulations and binding free energy calculations were combined to investigate the atomic-level mechanism of paraben binding to estrogen receptors (ERs). Computational analysis showed that ER were the targets of tested parabens and kept a stable agonist conformation. The calculated total binding free energies suggested that van der Waals interactions were the major driving forces for paraben-ER interaction and correlated with the structure of paraben side chains. In in vitro assays, paraben with an aromatic side chain, benzyl-paraben, showed the strongest estrogenic activity at 0.01 μM and the EC₅₀ at 0.796 ± 0.307 μM, on par with levels commonly detected in human organs. Among tested parabens with an alkyl side chain, the estrogenicity increased as the side chain length increased from 1 to 4, but no significant difference appeared between parabens with isomeric alkyl side chains (propyl- vs isopropyl and butyl- vs iso-butylparaben). The estrogenic activity of parabens was significantly related to the calculated binding energies (R² = 0.94, p = 0.0012), depending on the side chains of parabens. Our findings provide a significant mechanism for parabens to disrupt estrogenic function and considerations for structural optimization from the perspective of environmental protection.

Associations of per- and polyfluoroalkyl substances (PFAS) and their mixture with oxidative stress biomarkers during pregnancy

BACKGROUND

Oxidative stress from excess reactive oxygen species (ROS) is a hypothesized contributor to preterm birth. Per- and polyfluoroalkyl substances (PFAS) exposure is reported to generate ROS in laboratory settings, and is linked to adverse birth outcomes globally. However, to our knowledge, the relationship between PFAS and oxidative stress has not been examined in the context of human pregnancy.

OBJECTIVE

To investigate the associations between prenatal PFAS exposure and oxidative stress biomarkers among pregnant people.

METHODS

Our analytic sample included 428 participants enrolled in the Illinois Kids Development Study and Chemicals In Our Bodies prospective birth cohorts between 2014 and 2019. Twelve PFAS were measured in second trimester serum. We focused on seven PFAS that were detected in >65 % of participants. Urinary levels of 8-isoprostane-prostaglandin-F2α, prostaglandin-F2α, 2,3-dinor-8-iso-PGF2α, and 2,3-dinor-5,6-dihydro-8-iso-PGF2α were measured in the second and third trimesters as biomarkers of oxidative stress. We fit linear mixed-effects models to estimate individual associations between PFAS and oxidative stress biomarkers. We used quantile g-computation and Bayesian kernel machine regression (BKMR) to assess associations between the PFAS mixture and averaged oxidative stress biomarkers.

RESULTS

Linear mixed-effects models showed that an interquartile range increase in perfluorooctane sulfonic acid (PFOS) was associated with an increase in 8-isoprostane-prostaglandin-F2α (β = 0.10, 95 % confidence interval = 0, 0.20). In both quantile g-computation and BKMR, and across all oxidative stress biomarkers, PFOS contributed the most to the overall mixture effect. The six remaining PFAS were not significantly associated with changes in oxidative stress biomarkers.

CONCLUSIONS

Our study is the first to investigate the relationship between PFAS exposure and biomarkers of oxidative stress during human pregnancy. We found that PFOS was associated with elevated levels of oxidative stress, which is consistent with prior work in animal models and cell lines. Future research is needed to understand how prenatal PFAS exposure and maternal oxidative stress may affect fetal development.

Maternal diet quality moderates associations between parabens and birth outcomes

BACKGROUND/OBJECTIVE

Maternal paraben exposure and diet quality are both independently associated with birth outcomes, but whether these interact is unknown. We assessed sex-specific associations of parabens with birth outcomes and differences by maternal diet quality.

METHODS

Illinois pregnant women (n = 458) provided five first-morning urines collected at 8-40 weeks gestation, which we pooled for quantification of ethylparaben, methylparaben, and propylparaben concentrations. We collected/measured gestational age at delivery, birth weight, body length, and head circumference within 24 h of birth, and calculated sex-specific birth weight-for-gestational-age z-scores and weight/length ratio. Women completed three-month food frequency questionnaires in early and mid-to-late pregnancy, which we used to calculate the Alternative Healthy Eating Index (AHEI)-2010. Linear regression models evaluated sex-specific associations of parabens with birth outcomes, and differences in associations by average pregnancy AHEI-2010.

RESULTS

In this predominately non-Hispanic white, college-educated sample, maternal urinary paraben concentrations were only modestly inversely associated with head circumference and gestational length. However, methylparaben and propylparaben were inversely associated with birth weight, birth weight z-scores, body length, and weight/length ratio in female, but not male newborns. For example, each 2-fold increase in methylparaben concentrations was associated with -46.61 g (95% CI: -74.70, -18.51) lower birth weight, -0.09 (95% CI: -0.15, -0.03) lower birth weight z-scores, -0.21 cm (95% CI: -0.34, -0.07) shorter body length, and -0.64 g/cm (95% CI: -1.10, -0.19) smaller weight/length ratio in females. These inverse associations were more prominent in females of mothers with poorer diets (AHEI-2010 < median), but attenuated in those with healthier diets (AHEI-2010 ≥ median). In newborn males of mothers with healthier diets, moderate inverse associations emerged for propylparaben with gestational length and head circumference.

CONCLUSIONS

Maternal diet may moderate associations of parabens with birth size in a sex-specific manner. Additional studies may consider understanding the inflammatory and metabolic mechanisms underlying these findings.

Association between parabens concentrations in human amniotic fluid and the offspring birth size: A Sub-study of the PERSIAN birth cohort

OBJECTIVE

Parabens are extensively used, and cause widespread exposure of the general population including pregnant women and developing fetuses to these pollutants. In this study, we aimed to investigate the association between the maternal exposure of parabens to study their transfer passed through the placental barrier to amniotic fluid; the second objective was to determine the association of paraben concentration in the amniotic fluid with the offspring birth size.

METHODS

This cross-sectional study was conducted from June 2019 to March 2021 in Isfahan, Iran. Samples of amniotic fluid were collected as set from 128 pregnant women at Cesarean section. The amniotic fluid concentrations of four parabens including methylparaben (MP), ethylparaben (EP), propylparaben (PP), and butylparaben (BP) were determined using gas chromatography tandem mass spectroscopy (GC-Mass).

RESULTS

The pointed parabens were extracted from yielded clear supernatant using a dispersive liquid-liquid microextraction (DLLME) method. Four paraben derivatives including MP (normal: 0.68 ± 0.7; overweight: 1.40 ± 1.76; obese: 0.30 ± 0.26; p-value: 0.275), EP (normal: 0.14 ± 0.09; overweight: 0.72 ± 0.72; obese: 0.38 ± 0.05; p-value: 0.434), PP (normal: 0.05 ± 0.05; overweight: 0.06 ± 0.06; obese: 0.20 ± 0.17; p-value: 0.770), and BP (normal: 2.89 ± 1.80; overweight: 3.89 ± 6.48; obese: 5.80 ± 7.56; p-value: 0.341) were simultaneously detected in samples of maternal amniotic fluid using GC-MS. In 92.2% (n = 118) of pregnant women, the paraben derivatives (MP, EP, PP, BP) were detected. We found that considerable levels of MP, EP, PP, and BP existed in 22.6% (n = 29), 21.9% (n = 28), 29.7% (n = 38), and 85.2% (n = 109) of samples, respectively. In addition, the correlation between paraben concentrations in amniotic fluid and birth size was investigated. The results showed that an inverse significant association between MP and head circumference, chest, hip, and arm circumference. While a positive correlation between MP and height of newborn was observed. Similar correlations were observed for EP and weight, height, head circumference, chest, hip, and arm.

CONCLUSION

The current study indicated that parabens have been detected in amniotic fluid samples and a strong/possible correlation between exposure of pregnant women to parabens and the birth size of newborns.

Pregnancy Exposure to Phenols and Anthropometric Measures in Gestation and at Birth

BACKGROUND

Some synthetic phenols alter pathways involved in fetal development. Despite their high within-subject temporal variability, earlier studies relied on spot urine samples to assess pregnancy exposure. In this study, we examined associations between prenatal phenol exposure and fetal growth.

METHODS

We measured concentrations of two bisphenols, four parabens, benzophenone-3, and triclosan in 478 pregnant women in two weekly pools of 21 samples each, collected at 18 and 34 gestational weeks. We used adjusted linear regressions to study associations between phenol concentrations and growth outcomes assessed twice during pregnancy and at birth.

RESULTS

Benzophenone-3 was positively associated with all ultrasound growth parameters in at least one time point, in males but not females. In females, butylparaben was negatively associated with third-trimester abdominal circumference and weight at birth. We observed isolated associations for triclosan (negative) and for methylparaben and bisphenol S (positive) and late pregnancy fetal growth.

CONCLUSIONS

Our results suggest associations between prenatal exposure to phenols and fetal growth. Benzophenone-3 was the exposure most consistently (positively) associated across all growth parameters.

Assessment of human exposure to benzophenone-type UV filters: A review

To avoid the harmful effects of UV radiation, benzophenone-type UV filters (BPs) are widely used in personal care products and other synthetic products. Biomonitoring studies have shown the presence of BPs in various human biological samples, raising health concerns. However, there is a paucity of data on the global human exposure to this group of contaminants. In this study, we compiled data on the body burden of BPs along with the possible exposure routes and biotransformation pathways. BPs can easily penetrate the skin barrier and thus, they can be absorbed through the skin. In the human body, BPs can undergo Phase I (mainly demethylation and hydroxylation) and Phase II (mainly glucuronidation and sulfation) biotransformations. From a total of 158 studies, most of the studies are related to urine (concentration up to 92.7 mg L^-1), followed by those reported in blood (up to 0.9 mg L^-1) and milk (up to 0.8 mg L^-1). Among BPs, benzophenone-1 and benzophenone-3 are the most commonly detected congeners. The body burden of BPs is associated with various factors, including the country of residence, lifestyle, income, education level, and ethnicity. The presence of BPs in maternal urine (up to 1.1 mg L^-1), placenta (up to 9.8 ng g^-1), and amniotic fluid (up to 15.7 μg L^-1) suggests potential risks of prenatal exposure. In addition, transplacental transfer of BPs is possible, as demonstrated by their presence in maternal serum and cord serum. The possible association of BPs exposure and health effects was discussed. Future human biomonitoring studies and studies on the potential health effects are warranted. Overall, this review provides a summary of the global human exposure to BPs and can serve as supporting evidence to guide usage in order to protect humans from being exposed to BPs.

Polycyclic aromatic hydrocarbon exposure and DNA oxidative damage of workers in workshops of a petrochemical group

The petrochemical industry has promoted the development of economy, while polycyclic aromatic hydrocarbons (PAHs) produced by the industry become the threat for environment and humans. Data on human occupational exposure in petrochemical industry are limited. In the present study, urinary hydroxylated PAH metabolites (OH-PAHs) and a biomarker of DNA oxidative damage (8-hydroxy-2'-deoxyguanosine (8-OHdG)) were measured in 546 workers of a petrochemical group in Northeast China, to investigate PAH exposure and related potential health risk. The concentrations of ∑₉OH-PAH in all workers were 0.25-175 μg/g Cre with a median value of 4.41 μg/g Cre. Metabolites of naphthalene were the predominant compounds. The levels of PAH metabolites were significantly different for workers with different jobs, which were the highest for recycling workers (13.7 μg/g Cre) and the lowest for agency managers (5.12 μg/g Cre). Besides, higher levels of OH-PAHs were usually found in males and older workers. There was a dose-response relationship between levels of 8-OHdG and ∑₉OH-PAHs (p < 0.01). No difference was observed in concentrations of 8-OHdG for workers of different gender or ages, work history as well as noise. Furthermore, workers simultaneously exposed to other potential pollutants and higher levels of ∑₉OH-PAH had significantly higher levels of 8-OHdG compared with those in the corresponding subgroups. Our results suggested that exposure to PAHs or co-exposure to PAHs and potential toxics in the petrochemical plant may cause DNA damage. We call for more researches on the associations among noise, chemical pollution and oxidative stress to workers in the real working environment.

Pregnancy urinary concentrations of bisphenol A, parabens and other phenols in relation to serum levels of lipid biomarkers: Results from the EARTH study

The epidemiologic literature on associations between urinary phenol concentrations and lipid profiles during pregnancy is limited. We examined whether urinary concentrations of phenol and phenol replacement biomarkers were associated with serum lipid levels among pregnant women. This cross-sectional study included 175 women attending the Massachusetts General Hospital Fertility Center who enrolled in the Environment and Reproductive Health (EARTH) Study between 2005 and 2017 and had data available on urinary phenol biomarkers and serum lipids during pregnancy. We used linear regression models to assess the relationship between groups of urinary phenol and phenol replacement biomarkers and serum lipid levels [total cholesterol, high density lipoprotein (HDL), non-HDL, low-density lipoprotein (LDL) cholesterol, and triglycerides], while adjusting for age at sample collection, pre-pregnancy BMI, education, race, infertility diagnosis, cycle type, number of fetuses, trimester and specific gravity. In adjusted models, pregnant women with urinary propylparaben concentrations in the highest tertile had 10% [22 (95% CI = 5, 40) mg/dL], 12% [19 (95% CI = 2, 36) mg/dL] and 16% [19 (95% CI = 3, 35) mg/dL] higher mean total, non-HDL and LDL cholesterol, respectively, compared to women with concentrations in the lowest tertile. Similar elevations were observed for urinary bisphenol A concentrations. Urinary bisphenol S, benzophenone-3, triclosan, methylparaben, ethylparaben, and butylparaben were unrelated to serum lipids. Among pregnant women, urinary concentrations of bisphenol A and propylparaben were associated with higher serum levels of total, non-HDL and LDL cholesterol.