Relationships between blood chromium exposure and liver injury: Exploring the mediating role of systemic inflammation in a chromate-exposed population

Hexavalent chromium and its compounds are prevalent pollutants, especially in the work environment, pose a significant risk for multisystem toxicity and cancers. While it is known that chromium accumulation in the liver can cause damage, the dose-response relationship between blood chromium (Cr) and liver injury, as well as the possible potential toxic mechanisms involved, remains poorly understood. To address this, we conducted a follow-up study of 590 visits from 305 participants to investigate the associations of blood Cr with biomarkers for liver injury, including serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), and direct bilirubin (DBIL), and to evaluate the mediating effects of systemic inflammation. Platelet (PLT) and the platelet-to-lymphocyte ratio (PLR) were utilized as biomarkers of systemic inflammation. In the linear mixed-effects analyses, each 1-unit increase in blood Cr level was associated with estimated effect percentage increases of 0.82% (0.11%, 1.53%) in TBIL, 1.67% (0.06%, 3.28%) in DBIL, 0.73% (0.04%, 1.43%) in ALT and 2.08% (0.29%, 3.87%) in AST, respectively. Furthermore, PLT mediated 10.04%, 11.35%, and 10.77% increases in TBIL, DBIL, and ALT levels induced by chromate, respectively. In addition, PLR mediated 8.26% and 15.58% of the association between blood Cr and TBIL or ALT. These findings shed light on the mechanisms underlying blood Cr-induced liver injury, which is partly due to worsening systemic inflammation.

Associations of polychlorinated biphenyls exposure, lifestyle, and genetic susceptibility with dyslipidemias: Evidence from a general Chinese population

Polychlorinated biphenyls (PCBs) are endocrine-disrupting chemicals that have been associated with various adverse health conditions. Herein we explored the associations of PCBs with dyslipidemia and further assessed the modification effect of genetic susceptibility and lifestyle factors. Six serum PCBs (PCB-28, 101, 118, 138, 153, 180) were determined in 3845 participants from the Wuhan-Zhuhai cohort. Dyslipidemia, including hyper-total cholesterol (HyperTC), hyper-triglyceride (HyperTG), hyper-low density lipoprotein cholesterol (HyperLDL-C), and hypo-high density lipoprotein cholesterol (HypoHDL-C) were determined, and lipid-specific polygenic risk scores (PRS) and healthy lifestyle score were constructed. We found that all six PCB congeners were positively associated with the prevalence of dyslipidemias, and ΣPCB level was associated with HyperTC, HyperTG, and HyperLDL-C in dose-response manners. Compared with the lowest tertiles of ΣPCB, the odds ratios (95% confidence intervals) in the highest tertiles were 1.490 (1.258, 1.765) for HyperTC, 1.957 (1.623, 2.365) for HyperTG, and 1.569 (1.316, 1.873) for HyperLDL-C, respectively. Compared with those with low ΣPCB, healthy lifestyle, and low genetic risk, participants with high ΣPCB, unfavorable lifestyle, and high genetic risk had the highest odds of HyperTC, HyperTG, and HyperLDL-C. Our study provided evidence that high PCB exposure exacerbated the association of genetic risk and unhealthy lifestyle with dyslipidemia.

Effects of multiple metals exposure on abnormal liver function: The mediating role of low-density lipoprotein cholesterol

Equilibration of metal metabolism is critical for normal liver function. Most epidemiological studies have only concentrated on the influence of limited metals. However, the single and synergistic impact of multiple-metal exposures on abnormal liver function (ALF) are still unknown. A cross-sectional study involving 1493 Chinese adults residing in Shenzhen was conducted. Plasma concentrations of 13 metals, including essential metals (calcium, copper, cobalt, iron, magnesium, manganese, molybdenum, zinc, and selenium) and toxic metals (aluminum, cadmium, arsenic, and thallium) were detected by the inductively coupled plasma spectrometry (ICP-MS). ALF was ascertained as any observed abnormality from albumin, alanine transaminase, aspartate transaminase, γ-glutamyl transpeptidase, and direct bilirubin. Diverse statistical methods were used to evaluate the single and mixture effect of metals, as well as the dose-response relationships with ALF risk, respectively. Mediation analysis was conducted to evaluate the role of blood lipids in the relation of metal exposure with ALF. The average age of subjects was 59.7 years, and 56.7 % were females. Logistic regression and the least absolute shrinkage and selection operator (LASSO) penalized regression model consistently suggested that increased levels of arsenic, aluminum, manganese, and cadmium were related to elevated risk of ALF; while magnesium and zinc showed protective effects on ALF (all p-trend < 0.05). The grouped weighted quantile sum (GWQS) regression revealed that the WQS index of essential metals and toxic metals showed significantly negative or positive relationship with ALF, respectively. Aluminum, arsenic, cadmium, and manganese showed linear whilst magnesium and zinc showed non-linear dose-response relationships with ALF risk. Mediation analysis showed that LDL-c mediated 4.41 % and 14.74 % of the relationship of plasma cadmium and manganese with ALF, respectively. In summary, plasma aluminum, arsenic, manganese, cadmium, magnesium, and zinc related with ALF, and LDL-c might underlie the pathogenesis of ALF associated with cadmium and manganese exposure. This study may provide critical public health significances in liver injury prevention and scientific evidence for the establishment of environmental standard.

Exposure to per- and polyfluoroalkyl substances and high-throughput proteomics in Hispanic youth

BACKGROUND

Strong epidemiological evidence shows positive associations between exposure to per- and polyfluoroalkyl substances (PFAS) and adverse cardiometabolic outcomes (e.g., diabetes, hypertension, and dyslipidemia). However, the underlying cardiometabolic-relevant biological activities of PFAS in humans remain largely unclear.

AIM

We evaluated the associations of PFAS exposure with high-throughput proteomics in Hispanic youth.

MATERIAL AND METHODS

We included 312 overweight/obese adolescents from the Study of Latino Adolescents at Risk (SOLAR) between 2001 and 2012, along with 137 young adults from the Metabolic and Asthma Incidence Research (Meta-AIR) between 2014 and 2018. Plasma PFAS (i.e., PFOS, PFOA, PFHxS, PFHpS, PFNA) were quantified using liquid-chromatography high-resolution mass spectrometry. Plasma proteins (n = 334) were measured utilizing the proximity extension assay using an Olink Explore Cardiometabolic Panel I. We conducted linear regression with covariate adjustment to identify PFAS-associated proteins. Ingenuity Pathway Analysis, protein-protein interaction network analysis, and protein annotation were used to investigate alterations in biological functions and protein clusters.

RESULTS

Results after adjusting for multiple comparisons showed 13 significant PFAS-associated proteins in SOLAR and six in Meta-AIR, sharing similar functions in inflammation, immunity, and oxidative stress. In SOLAR, PFNA demonstrated significant positive associations with the largest number of proteins, including ACP5, CLEC1A, HMOX1, LRP11, MCAM, SPARCL1, and SSC5D. After considering the mixture effect of PFAS, only SSC5D remained significant. In Meta-AIR, PFAS mixtures showed positive associations with GDF15 and IL6. Exploratory analysis showed similar findings. Specifically, pathway analysis in SOLAR showed PFOA- and PFNA-associated activation of immune-related pathways, and PFNA-associated activation of inflammatory response. In Meta-AIR, PFHxS-associated activation of dendric cell maturation was found. Moreover, PFAS was associated with common protein clusters of immunoregulatory interactions and JAK-STAT signaling in both cohorts.

CONCLUSION

PFAS was associated with broad alterations of the proteomic profiles linked to pro-inflammation and immunoregulation. The biological functions of these proteins provide insight into potential molecular mechanisms of PFAS toxicity.

Dietary intake of Perfluorooctanesulfonic acid (PFOS) and glucose homeostasis parameters in a non-diabetic senior population

BACKGROUND

Endocrine disruptors (EDs) have emerged as potential contributors to the development of type-2 diabetes. Perfluorooctane sulfonate (PFOS), is one of these EDs linked with chronic diseases and gathered attention due to its widespread in food.

OBJECTIVE

To assess at baseline and after 1-year of follow-up associations between estimated dietary intake (DI) of PFOS, and glucose homeostasis parameters and body-mass-index (BMI) in a senior population of 4600 non-diabetic participants from the PREDIMED-plus study.

METHODS

Multivariable linear regression models were conducted to assess associations between baseline PFOS-DI at lower bound (LB) and upper bound (UB) established by the EFSA, glucose homeostasis parameters and BMI.

RESULTS

Compared to those in the lowest tertile, participants in the highest tertile of baseline PFOS-DI in LB and UB showed higher levels of HbA1c [β-coefficient(CI)] [0.01 %(0.002 to 0.026), and [0.06 mg/dL(0.026 to 0.087), both p-trend ≤ 0.001], and fasting plasma glucose in the LB PFOS-DI [1.05 mg/dL(0.050 to 2.046),p-trend = 0.022]. Prospectively, a positive association between LB of PFOS-DI and BMI [0.06 kg/m2(0.014 to 0.106) per 1-SD increment of energy-adjusted PFOS-DI was shown. Participants in the top tertile showed an increase in HOMA-IR [0.06(0.016 to 0.097), p-trend = 0.005] compared to participants in the reference tertile after 1-year of follow-up.

DISCUSSION

This is the first study to explore the association between DI of PFOS and glucose homeostasis. In this study, a high baseline DI of PFOS was associated with a higher levels of fasting plasma glucose and HbA1c and with an increase in HOMA-IR and BMI after 1-year of follow-up.

First trimester plasma PER- AND Polyfluoroalkyl Substances (PFAS) and blood pressure trajectories across the second and third trimesters of pregnanacy

BACKGROUND

Evidence suggests that exposure to per- and polyfluoroalkyl substances (PFAS) increases risk of high blood pressure (BP) during pregnancy. Prior studies did not examine associations with BP trajectory parameters (i.e., overall magnitude and velocity) during pregnancy, which is linked to adverse pregnancy outcomes.

OBJECTIVES

To estimate associations of multiple plasma PFAS in early pregnancy with BP trajectory parameters across the second and third trimesters. To assess potential effect modification by maternal age and parity.

METHODS

In 1297 individuals, we quantified six PFAS in plasma collected during early pregnancy (median gestational age: 9.4 weeks). We abstracted from medical records systolic BP (SBP) and diastolic BP (DBP) measurements, recorded from 12 weeks gestation until delivery. BP trajectory parameters were estimated via Super Imposition by Translation and Rotation modeling. Subsequently, Bayesian Kernel Machine Regression (BKMR) was employed to estimate individual and joint associations of PFAS concentrations with trajectory parameters - adjusting for maternal age, race/ethnicity, pre-pregnancy body mass index, income, parity, smoking status, and seafood intake. We evaluated effect modification by age at enrollment and parity.

RESULTS

We collected a median of 13 BP measurements per participant. In BKMR, higher concentration of perfluorooctane sulfonate (PFOS) was independently associated with higher magnitude of overall SBP and DBP trajectories (i.e., upward shift of trajectories) and faster SBP trajectory velocity, holding all other PFAS at their medians. In stratified BKMR analyses, participants with ≥ 1 live birth had more pronounced positive associations between PFOS and SBP velocity, DBP magnitude, and DBP velocity - compared to nulliparous participants. We did not observe significant associations between concentrations of the overall PFAS mixture and either magnitude or velocity of the BP trajectories.

CONCLUSION

Early pregnancy plasma PFOS concentrations were associated with altered BP trajectory in pregnancy, which may impact future cardiovascular health of the mother.

Estimating the dynamic early life exposure to PFOA and PFOS of the HELIX children: Emerging profiles via prenatal exposure, breastfeeding, and diet

In utero and children's exposure to per- and polyfluoroalkyl substances (PFAS) is a major concern in health risk assessment as early life exposures are suspected to induce adverse health effects. Our work aims to estimate children's exposure (from birth to 12 years old) to PFOA and PFOS, using a Physiologically-Based Pharmacokinetic (PBPK) modelling approach. A model for PFAS was updated to simulate the internal PFAS exposures during the in utero life and childhood, and including individual characteristics and exposure scenarios (e.g., duration of breastfeeding, weight at birth, etc.). Our approach was applied to the HELIX cohort, involving 1,239 mother-child pairs with measured PFOA and PFOS plasma concentrations at two sampling times: maternal and child plasma concentrations (6 to 12 y.o). Our model predicted an increase in plasma concentrations during fetal development and childhood until 2 y.o when the maximum concentrations were reached. Higher plasma concentrations of PFOA than PFOS were predicted until 2 y.o, and then PFOS concentrations gradually became higher than PFOA concentrations. From 2 to 8 y.o, mean concentrations decreased from 3.1 to 1.88 µg/L or ng/mL (PFOA) and from 4.77 to 3.56 µg/L (PFOS). The concentration-time profiles vary with the age and were mostly influenced by in utero exposure (on the first 4 months after birth), breastfeeding (from 5 months to 2 (PFOA) or 5 (PFOS) y.o of the children), and food intake (after 3 (PFOA) or 6 (PFOS) y.o of the children). Similar measured biomarker levels can correspond to large differences in the simulated internal exposures, highlighting the importance to investigate the children's exposure over the early life to improve exposure classification. Our approach demonstrates the possibility to simulate individual internal exposures using PBPK models when measured biomarkers are scarce, helping risk assessors in gaining insight into internal exposure during critical windows, such as early life.

An investigation of 3M Cordova, IL production worker's per- and polyfluoroalkyl substances biomonitoring results and mortality experience

Per- and polyfluoroalkyl substances (PFAS) are a wide-ranging group of chemicals that have been used in a variety of polymer and surfactant applications. While 3M Cordova, Illinois was not one of 3M's primary manufacturing facilities for the legacy long-chain PFAS (PFOS, PFOA, PFHxS), it has been a major manufacturing site for short-chain PFAS (compounds that are or may degrade to PFBS or PFBA). The purpose of this research focused on: 1) an analysis of biomonitoring data of employees and retirees, and 2) an analysis of the cohort mortality of workers from 1970 to 2018. Employees had higher PFBS and PFBA serum concentrations than the retirees, while retirees had higher concentrations for PFOS, PFOA, and PFHxS. Compared to the 2017-2018 NHANES data, employees' PFOS and PFHxS concentrations in 2022 were two-fold higher, with PFOA levels comparable. These NHANES data did not include serum PFBS or PFBA. Cross-sectional trends of PFOS and PFOA levels from 1997 to 2022 showed PFOS declined from 151 ng/mL to 10.4 ng/mL. Similarly, PFOA decreased from 100 ng/mL to 1.5 ng/mL. A longitudinal analysis of 48 participants with measurements in both 2006 and 2022 showed concentrations decreased by 74% for PFOS and 90% for PFOA. In the mortality study, 1707 employees who worked 1 day or longer were followed for an average of 25.6 years and had 143 (8%) deaths. There were no significantly elevated risks for any specific cause of death, regardless of latency period (0 or 15 years). While no specific PFAS exposures were examined, worker mortality experience (1970-2018) was analyzed by major departments representing primary work areas. Employees and retirees at the Cordova facility continue to have elevated PFOS and PFHxS serum concentrations compared to the general population, however, their legacy PFAS concentrations have declined over time, consistent with the estimated serum elimination half-lives of these PFAS in humans assuming nominal ambient exposures. For PFBS and PFBA, the results indicated no long-term accumulation in the blood likely due to their short serum elimination half-lives. After nearly 50 years of follow-up, this Cordova workforce showed no increased risk of mortality from cancer or any other specific cause of death.

A pilot study of several environmental endocrine disrupting chemicals in children with autism spectrum disorder in south China

Autism spectrum disorders (ASD) is a group of heterogeneous neurodevelopmental disorders. Evidence has implied that environmental pollutants are important factors related to ASD. In this study, several environmental endocrine-disrupting chemicals, including parabens, benzophenone-type ultraviolet filters, hydroxyl polycyclic aromatic hydrocarbons, triclosan and tetrabromobisphenol A were analyzed in blood plasma in ASD children (n = 34) and the control children (n = 28). The results showed that parabens were the most concentrated chemicals (2.18 ng/mL, median value), followed by hydroxyl polycyclic aromatic hydrocarbons (0.73 ng/mL), benzophenone-type ultraviolet filters (0.14 ng/mL), triclosan (0.13 ng/mL) and tetrabromobisphenol A (0.03 ng/mL). ASD children accumulated significantly lower 2-hydroxy-4-methoxybenzophenone, 2,4-dihydroxybenzophenone, 4-hydroxybenzophenone and triclosan but higher 2-hydroxyphenanthrene and tetrabromobisphenol A than the control children (0.02/0.09 ng/mL of 2-hydroxy-4-methoxybenzophenone, p < 0.05; 0.04/0.07 ng/mL of 2,4-dihydroxybenzophenone, p < 0.05; 0.03/0.04 ng/mL of 4-hydroxybenzophenone, p < 0.05; 0.13/1.22 ng/mL of triclosan, p < 0.01; 0.03 ng/mL/not detected of 2-hydroxyphenanthrene, p < 0.05; 0.03/0.004 ng/mL of tetrabromobisphenol A, p < 0.05). Gender differences in certain environmental endocrine-disrupting chemicals were evident, and the differences were more inclined toward boys. Positive associations between 2-hydroxy-4-methoxybenzophenone and triclosan, and tetrabromobisphenol A and 2-hydroxyphenanthrene were found in ASD boys. Binary logistic regression analysis showed that the adjusted odds ratio value of 2-hydroxyphenanthrene in ASD boys was 11.0 (1.45-84.0, p < 0.05). This is the first pilot study on multiple environmental endocrine-disrupting chemicals in children with ASD in China.

Direct analysis of hydroxylated polycyclic aromatic hydrocarbons in biological samples with complex matrices using polarity-reversed nanoelectrospray ionization

RATIONALE

Polycyclic aromatic hydrocarbons (PAHs) are a class of environmental contaminants with carcinogenic effect drawing worldwide attention. PAHs can be converted into hydroxylated PAHs (OH-PAHs) through metabolic processes. Thus, they are commonly considered as an important class of biomarkers of PAH exposure. However, direct analysis of related metabolites of these environmental pollutants in biological samples using mass spectrometry is still challenging because of matrix effect and ion suppression during nanoelectrospray ionization (nano-ESI).

METHODS

In our previous work, a polarity-reversed nanoelectrospray ionization (PR-nESI) technique was developed for the analysis of biomolecules in complex matrices. In this work, we further optimized PR-nESI for direct and sensitive analysis of OH-PAHs in different samples under severe salt interference in negative polarity.

RESULTS

Compared with conventional nano-ESI, the optimized PR-nESI method realized sensitive detection of 1-naphthol in samples with a concentration of salt up to millimolar level. The signal-to-noise ratio (S/N) of OH-PAHs was increased by 1-2 orders of magnitude compared with conventional nano-ESI. Six different OH-PAHs were successfully detected with high S/N ratio using PR-nESI. PR-nESI was further successfully applied in the analysis of OH-PAHs in spiked fetal blood serum, human urine, and single-cell samples. For environmentally exposed subjects, the detections of OH-PAHs in single-cell samples and urines from human smokers were successfully conducted.

CONCLUSION

The optimized PR-nESI method was successfully applied for the sensitive analysis of OH-PAHs in complex biological samples with severe salt effects. Based on the present study, PR-nESI can have a promising prospect for the sensitive analysis of other metabolites of environmental pollutants in negative polarity.

Pregnancy Exposure to Perfluoroalkyl Substances and Associations With Prolactin Concentrations and Breastfeeding in the Odense Child Cohort

CONTEXT

Human exposure to perfluoroalkyl substances (PFAS) has been associated with reduced duration of breastfeeding, although not consistently so, and mechanisms by which PFAS might affect breastfeeding are unknown.

OBJECTIVE

To examine the association between early pregnancy serum-PFAS concentrations and breastfeeding termination and to elucidate the potential role of serum-prolactin concentrations in pregnancy.

MATERIALS AND METHODS

Pregnant women from the Odense Child Cohort provided blood samples for analysis of 5 major PFAS (n = 1300) and prolactin concentrations (n = 924). They subsequently provided information about the duration of breastfeeding in questionnaires at 3 and 18 months postpartum, and a subgroup also provided breastfeeding information via weekly cell phone text messages. Associations between serum-PFAS concentrations and breastfeeding termination were analyzed using Cox regressions, while linear regression was used to assess associations between serum-PFAS and prolactin concentrations.

RESULTS

Increased serum concentrations of perfluorooctane sulfonic acid, perfluorooctanoic acid, perfluorononanoic acid, and ∑PFAS were associated with a 16% (95% CI: 4%-30%), 14% (95% CI: 2%-26%), 14% (95% CI: 3%-27%), and 20% (95% CI: 6%-36%), respectively, increased risk of terminating breastfeeding at any given time after childbirth. Serum-PFAS concentrations were not associated with serum-prolactin concentrations.

CONCLUSIONS

These findings are of public health importance due to the global exposures to PFAS. Because breastfeeding is crucial to promote both child health and maternal health, adverse PFAS effects on the ability to breastfeed may have long-term health consequences.

Genetically determined blood lead is associated with reduced renal function amongst individuals with type 2 diabetes mellitus: insight from Mendelian Randomisation

Some observational studies indicate a link between blood lead and kidney function although results remain controversial. In this study, Mendelian randomisation (MR) analysis was applied to obtain unconfounded estimates of the casual association of genetically determined blood lead with estimated glomerular filtration rate (eGFR) and the risk of chronic kidney disease (CKD). Data from the largest genome-wide association studies (GWAS) on blood lead, eGFR and CKD, from predominantly ethnically European populations, were analysed in total, as well as separately in individuals with or without type 2 diabetes mellitus. Inverse variance weighted (IVW) method, weighted median (WM)-based method, MR-Egger, MR-Pleiotropy RESidual Sum and Outlier (PRESSO) as well as the leave-one-out method were applied. In a general population, lifetime blood lead levels had no significant effect on risk of CKD (IVW: p = 0.652) and eGFR (IVW: p = 0.668). After grouping by type 2 diabetes status (no diabetes vs. diabetes), genetically higher levels of blood lead had a significant negative impact among subjects with type 2 diabetes (IVW = Beta: -0.03416, p = 0.0132) but not in subjects without (IVW: p = 0.823), with low likelihood of heterogeneity for any estimates (IVW p > 0.158). MR-PRESSO did not highlight any outliers. Pleiotropy test, with very negligible intercept and insignificant p-value, indicated a low likelihood of pleiotropy for all estimations. The leave-one-out method demonstrated that links were not driven by a single SNP. Our results show, for the first time, that among subjects with type 2 diabetes, higher blood lead levels are potentially related to less favourable renal function. Further studies are needed to confirm our results. KEY MESSAGES: What is already known about this subject? Chronic kidney disease is associated with unfavourable lifestyle behaviours and conditions such as type 2 diabetes. Observational studies have reported an association between blood lead and reduced estimated glomerular filtration rate, but the relationship between lead exposure and renal function remains controversial. What is the key question? Using Mendelian randomisation with data from 5433 individuals from the UK and Australian populations, does genetically determined blood lead have a potentially causal effect on estimated glomerular filtration rate and the risk of chronic kidney disease? What are the new findings? Blood lead levels have a potentially causal effect on reduced renal function in individuals with type 2 diabetes. In subjects without diabetes, no such causal relationship was identified. How might this impact on clinical practice in the foreseeable future? This highlights the risk of elevated blood lead, for example, due to environmental exposure, amongst those with type 2 diabetes, which may predispose them to impaired renal function.

Blood lead level and nutritional status indicators in preadolescent Polish schoolchildren

BACKGROUND

Environmental pollutions with heavy metals may have toxic effects on human health and development. One of the most detrimental is lead exposure, which may disturb neurodevelopment and linear growth in children. However, data on the effect of lead exposure on nutritional and weight status in children are limited, thus this study aimed to assess the effect of blood lead (Pb) level on nutritional and weight status in preadolescent schoolchildren from the industrialized, mining region in southwestern Poland.

METHODS

Our study sample involved N = 709 schoolchildren (402 boys and 307 girls) in the preadolescent developmental period (7-11 years of age for boys and 7-10 years of age for girls). Anthropometric measurements were used to assess nutritional and weight status: body mass index (BMI), mid-upper arm circumference (MUAC) and skinfolds thicknesses (triceps, subscapular, abdominal and the sum of skinfolds). Blood Pb level was evaluated and divided into two groups: above (>3.7 μg/dL) and below median value (≤3.7 μg/dL).

RESULTS

Analysis of covariance (with children's age controlled as a covariate) revealed that children with blood Pb level above median value had significantly lower values of BMI, MUAC and all skinfolds (at least p < 0.01). However, this effect was significant only in boys, whereas in girls differences were non-significant (p > 0.05). The highest effect size of blood Pb level was noted for skinfolds thicknesses (partial η²: 0.015 for the sum of skinfolds).

CONCLUSIONS

Nutritional status in children with higher blood Pb level is significantly impaired in preadolescent boys, who appear to be more sensitive to this environmental factor. Our findings indicate a particular need for nutritional and environmental interventions among preadolescent children in regions with higher lead exposure.

Does sulfuric acid have a 'protective' effect on battery recyclers exposed to lead?

Culturally significant interventions to prevent lead exposure of battery recyclers are required. Sulfuric acid used in batteries causes skin lesions and could facilitate the recognition of hazards. This study explored whether joint exposure to lead and sulfuric acid can be used in interventions to manage hazardous work conditions. Data were collected from 120 informal workers, and the blood lead level was measured. Predictors of blood lead levels were explored using a tobit model. The median blood lead level was 9.45 µg/dL (Q₇₅-Q₂₅: 48.9 µg/dL); when lead and sulfuric acid exposure occurred, the level increased to 11.44 µg/dL, and when exposure to lead and other substances occurred, the level was 11.50 µg/dL. Workers are unaware of the risks of obvious and acute silent chronic exposure. Future preventive interventions could confront the economic benefits of battery recycling with the recognition of susceptibility and severity related to lead and sulfuric acid exposure.

Exposure to organochlorine pesticides as a predictor to breast cancer: A case-control study among Ethiopian women

Breast cancer (BC) is becoming one of the most prevalent non-infectious disease in low and middle income countries. The steady rise of BC incidence may be related to the different risk factors. Among many, rampant presence of environmental pollutants might be one of the risk factors. Therefore, the aim of this study is to investigate exposure to organochlorine pesticides as a risk factor to breast cancer. A case-control study design was employed among breast cancer patients and non-breast cancer individuals (controls). Blood samples were collected from 100 study participants (50 cases and 50 controls) followed by serum separation, extraction and cleanup using standard analytical procdures. The findings revealed that ten organochlorine pesticides were detected in the serum of the study participants. From the detected organochlorine pesticides, heptachlor was observed at higher concentration for breast cancer patients (6.90±4.37 μg/L) and controls (9.15±3.84 μg/L). Mean serum level of p,p’-DDE, p,p’-DDT, heptachlor, gamma-chlordane, endosulfan, and dibutyl-chlorendate were significantly higher in the serum of breast cancer patients than the controls. From the studied pesticides, p,p’-DDT and gamma-chlordane are significant predictors for BC, while, others are equivocal. A unit increment of the concentration of p,p’-DDT (AOR; 2.03, 95% CI: 1.041–3.969) increased the odds of developing breast cancer by two, while for gamma-chlordane (AOR;3.12, 95% CI; 1.186–8.203) by three. Our study results suggesting that, organochlorines are a risk factors for breast cancer in Ethiopia. Decreasing exposure to such organochlorines might have a significant public health relevance in reducing non-communicable chronic illnesses. Besides, continues monitoring of persistent organic pollutants using body biomarkers is important for disease prevention and device mitigation measures.

Associations among maternal perfluoroalkyl substance levels, fetal sex-hormone enzymatic gene polymorphisms, and fetal sex hormone levels in the Hokkaido study

Prenatal sex hormones affect fetal growth; for example, prenatal exposure to low levels of androgen accelerates female puberty onset. We assessed the association of perfluoroalkyl substances (PFASs) in maternal sera and infant genotypes of genes encoding enzymes involved in sex steroid hormone biosynthesis on cord sera sex hormone levels in a prospective birth cohort study of healthy pregnant Japanese women (n = 224) recruited in Sapporo between July 2002 and October 2005. We analyzed PFAS and five sex hormone levels using liquid chromatography-tandem mass spectrometry. Cytochrome P450 (CYP) 17A1 (CYP17A1 rs743572), 19A1 (CYP19A1 rs10046, rs700519, and rs727479), 3β-hydroxysteroid dehydrogenase type 1 (HSD3B1 rs6203), type 2 (HSD3B2 rs1819698, rs2854964, and rs4659175), 17β-hydroxysteroid dehydrogenase type 1 (HSD17B1 rs605059, rs676387, and rs2676531), and type 3 (HSD17B3 rs4743709) were analyzed using real-time PCR. Multiple linear regression models were used to establish the influence of log₁₀-transformed PFAS levels and infant genotypes on log₁₀-transformed sex steroid hormone levels. When the interaction between perfluorooctanesulfonate (PFOS) levels and female infant genotype CYP17A1 (rs743572) on the androstenedione (A-dione) levels was considered, the estimated changes (95 % confidence intervals) in A-dione levels against PFOS levels, female infant genotype CYP17A1 (rs743572)-AG/GG, and interaction between them showed a mean increase of 0.445 (0.102, 0.787), mean increase of 0.392 (0.084, 0.707), and mean reduction of 0.579 (0.161, 0.997) (P_int = 0.007), respectively. Moreover, a female-specific interaction with testosterone levels was observed. A-dione and T levels showed positive main effects and negative interaction with PFOS levels and the female infant CYP17A1 genotype.

Antimony exposure promotes bladder tumor cell growth by inhibiting PINK1-Parkin-mediated mitophagy

Antimony is one of the heavier pnictogens and is widely found in human food chains, water sources, and as an air pollutant. Recent years have seen steadily increasing concentrations of antimony in the ecological environment; critically, several studies have indicated that antimony might pose a tumorigenic risk factor in several cancers. Therefore, antimony toxicity has attracted increasing research attention, with the molecular mechanisms underlying suspected antimony-mediated tumor transformation of greatest interest. Our results showed that the serum concentration of antimony was higher in bladder tumor patients relative to levels in non-tumor patients. Moreover, that such high antimony serum concentration were closely associated with poorer outcome in bladder tumor patients. Additionally, we demonstrated that the presence of antimony promoted both in vitro and in vivo bladder tumor cell growth. Our results also indicated that low-dose antimony resulted in significantly decreased mitochondrial membrane potential, mitochondrial respiratory enzyme complex I/II/III/IV activity, ATP/ADP ratio, and ATP concentration relative to the control group. These findings suggested that antimony caused mitochondrial damage. Finally, we found that low-dose antimony(0.8uM) inhibited mitophagy by deregulating expression of PINK1, Parkin, and p(ser65)-Parkin, and activation of PINK1-Parkin pathway by CCCP could inhibit antimony-induced tumor cell growth. Collectively, this inhibited the proliferation of bladder tumor cells. Overall, our study suggested that antimony promoted bladder tumor cell growth by inhibiting PINK1-Parkin-mediated mitophagy. These findings highlight the therapeutic potential in targeting molecules within this antimony induced-PINK1/Parkin signaling pathway and may offer a new approach for the treatment of bladder cancer.

Bisphenol-A exposure and risk of breast and prostate cancer in the Spanish European Prospective Investigation into Cancer and Nutrition study

BACKGROUND

Bisphenol A (BPA) is an endocrine disruptor that it is present in numerous products of daily use. The aim of this study was to assess the potential association of serum BPA concentrations and the risk of incident breast and prostate cancer in a sub-cohort of the Spanish European Prospective Investigation into Cancer and Nutrition (EPIC).

METHODS

We designed a case-cohort study within the EPIC-Spain cohort. Study population consisted on 4812 participants from 4 EPIC-Spain centers (547 breast cancer cases, 575 prostate cancer cases and 3690 sub-cohort participants). BPA exposure was assessed by means of chemical analyses of serum samples collected at recruitment. Borgan II weighted Cox regression was used to estimate hazard ratios.

RESULTS

Median follow-up time in our study was 16.9 years. BPA geometric mean serum values of cases and sub-cohort were 1.12 ng/ml vs 1.10 ng/ml respectively for breast cancer and 1.33 ng/ml vs 1.29 ng/ml respectively for prostate cancer. When categorizing BPA into tertiles, a 40% increase in risk of prostate cancer for tertile 1 (p = 0.022), 37% increase for tertile 2 (p = 0.034) and 31% increase for tertile 3 (p = 0.072) was observed with respect to values bellow the limit of detection. No significant association was observed between BPA levels and breast cancer risk.

CONCLUSIONS

We found a similar percentage of detection of BPA among cases and sub-cohort from our population, and no association with breast cancer risk was observed. However, we found a higher risk of prostate cancer for the increase in serum BPA levels. Further investigation is needed to understand the influence of BPA in prostate cancer risk.

Life-course Exposure to Perfluoroalkyl Substances in Relation to Markers of Glucose Homeostasis in Early Adulthood

OBJECTIVE

To investigate the prospective associations of life-course perfluoroalkyl substances (PFASs) exposure with glucose homeostasis at adulthood.

METHODS

We calculated insulin sensitivity and beta-cell function indices based on 2-h oral glucose tolerance tests at age 28 in 699 Faroese born in 1986-1987. Five major PFASs were measured in cord whole blood and in serum from ages 7, 14, 22, and 28 years. We evaluated the associations with glucose homeostasis measures by PFAS exposures at different ages using multiple informant models fitting generalized estimating equations and by life-course PFAS exposures using structural equation models.

RESULTS

Associations were stronger for perfluorooctane sulfonate (PFOS) and suggested decreased insulin sensitivity and increased beta-cell function-for example, β (95% CI) for log-insulinogenic index per PFOS doubling = 0.12 (0.02, 0.22) for prenatal exposures, 0.04 (-0.10, 0.19) at age 7, 0.07 (-0.07, 0.21) at age 14, 0.05 (-0.04, 0.15) at age 22, and 0.04 (-0.03, 0.11) at age 28. Associations were consistent across ages (P for age interaction > 0.10 for all PFASs) and sex (P for sex interaction > 0.10 for all PFASs, except perfluorodecanoic acid). The overall life-course PFOS exposure was also associated with altered glucose homeostasis (P = 0.04). Associations for other life-course PFAS exposures were nonsignificant.

CONCLUSIONS

Life-course PFAS exposure is associated with decreased insulin sensitivity and increased pancreatic beta-cell function in young adults.

Effect of lead exposure from electronic waste on haemoglobin synthesis in children

BACKGROUND

Primitive electronic waste (e-waste) recycling is ongoing in Guiyu, so toxic heavy metals may continue to threaten the health of children in the area.

OBJECTIVE

This study primarily aimed to evaluate the effect of e-waste exposure on haemoglobin (Hb) synthesis in preschool children.

METHODS

Medical examinations were conducted with the permission of children's guardians and the approval of the Ethics Committee of the Medical College of Shantou University. This study recruited 224 children (aged 3-6 years, exposed group) who lived in Guiyu and 204 children (aged 3-6 years, control group) who lived in a town free of e-waste pollution. Blood levels of lead, Hb, ferritin, folate and vitamin B₁₂ were tested in all children. Furthermore, all children were assessed for thalassemia, and their parents were asked to fill in questionnaires.

RESULTS

There were no significant differences in the level of ferritin, folate, or vitamin B₁₂ between the exposed and control groups (P > 0.05). No children were identified as having thalassemia in all study participants. Blood lead level (BLL) and the risk of children with BLL ≥ 10 µg/dL in the exposed group were significantly higher than those in the control group (all P < 0.01). Three subgroups of each group were created according to BLL (Group A: < 5.0 µg/dL; Group B: 5.0-9.9 µg/dL; Group C: ≥ 10.0 µg/dL). Hb level decreased with elevated BLL in the exposed group (P = 0.03), but not in the control group (P = 0.14). Hb levels in group B and group C were also significantly lower in the exposed group than in the control group (Group B: 122.6 ± 9.5 g/L versus 125.8 ± 8.2 g/L, P = 0.01; Group C: 120.3 ± 7.3 g/L versus 123.6 ± 8.3 g/L, P = 0.03). In addition, the prevalence of anaemia associated with BLLs above 10 µg/dL and between 5.0 and 9.9 µg/dL were both significantly higher in the exposed group than in the control group (4.0% vs. 0.5%, 5.4% vs. 1.5%, respectively, both P < 0.05).

CONCLUSION

Lead exposure more significantly inhibits Hb synthesis in children who live in e-waste dismantling areas than in those who live in non-e-waste dismantling areas. Other toxins released from e-waste may also contribute to the inhibition of Hb synthesis and may lead to anaemia in local children. Further investigations are needed to provide evidence for the development of relevant protective measures.

Distribution of mercury in serum and blood cells and risk of spontaneous preterm birth: A nested case-control study in China

The relationship between maternal mercury (Hg) intake and the risk of spontaneous preterm birth (SPB) remains unclear. We conducted a nested case-control study from a prospective cohort in Shanxi Province, China, to explore their associations. In total, 126 pregnant women with SPB (cases) and 348 controls with term delivery were included. We measured the Hg concentrations in their serum (Hg^s) and blood cell (Hg^c) fractions and calculated the concentration ratio of Hg in serum to Hg in blood cells (Hg^s/c). We found that only the Hg^s/c in the case group was slightly higher than that in control group. The OR of Hg^s/c associated with SPB risk was 1.57 [95%CI: 0.99-2.46] with adjusting confounders. After stratification by sampling time, the association above was only statistically significant in the first trimester. High Hg^s/c may increase the risk of SPB in the first trimester among women with relatively low Hg exposure.

Associations between exposure to perfluoroalkyl substances and body fat evaluated by DXA and MRI in 109 adolescent boys

BACKGROUND

Exposure to perfluoroalkyl substances (PFASs) has been associated with changes in body mass index and adiposity, but evidence is inconsistent as study design, population age, follow-up periods and exposure levels vary between studies. We investigated associations between PFAS exposure and body fat in a cross-sectional study of healthy boys.

METHODS

In 109 boys (10-14 years old), magnetic resonance imaging and dual-energy X-ray absorptiometry were performed to evaluate abdominal, visceral fat, total body, android, gynoid, android/gynoid ratio, and total fat percentage standard deviation score. Serum was analysed for perfluorooctanoic acid, perfluorooctane sulfonic acid (PFOS), perfluorohexane sulfonic acid, perfluorononanoic acid, and perfluorodecanoic acid using liquid chromatography and triple quadrupole mass spectrometry. Data were analysed by multivariate linear regression.

RESULTS

Serum concentrations of PFASs were low. Generally, no clear associations between PFAS exposure and body fat measures were found; however, PFOS was negatively associated with abdominal fat (β = -0.18, P = 0.046), android fat (β = -0.34, P = 0.022), android/gynoid ratio (β = -0.21, P = 0.004), as well as total body fat (β = -0.21, P = 0.079) when adjusting for Tanner stage.

CONCLUSIONS

Overall, we found no consistent associations between PFAS exposure and body fat. This could be due to our cross-sectional study design. Furthermore, we assessed PFAS exposure in adolescence and not in utero, which is considered a more vulnerable time window of exposure.

Circulatory cadmium positively correlates with epithelial-mesenchymal transition in patients with chronic obstructive pulmonary disease

Environmental cadmium (Cd) exposure can cause several pulmonary diseases. Epithelial-mesenchymal transition (EMT) involved in the process of chronic obstructive pulmonary disease (COPD). However, the association between environmental Cd exposure and EMT was unclear in COPD patients. This study aimed to analyze the associations among circulatory Cd, EMT and COPD based on case-control study. Four hundred COPD patients and 400 control subjects were recruited. Circulatory Cd was detected using atomic adsorption spectrometer. MicroRNA-30 (miR-30) was measured by RT-PCR and the markers of pulmonary EMT were evaluated through western blotting. Circulatory Cd concentration was increased and serum miR-30 was decreased in COPD patients. Circulatory Cd was inversely associated with pulmonary function in COPD patients. Moreover, serum miR-30 was gradually decreased in parallel with FEV1 in COPD patients. Meanwhile, there was a negative association between serum miR-30 and circulatory Cd in COPD patients. Further analysis found that E-cadherin, one of epithelial biomarkers, was reduced in lung tissues of COPD patients with higher circulatory Cd. On the contrary, pulmonary N-cadherin, Vimentin and α-SMA, three of mesenchymal biomarkers, were increased in COPD patients with higher circulatory Cd. In vitro experiments revealed that Cd exposure repressed miR-30 levels and promoted EMT in BEAS-2B cells. Our results provide evidence that miR-30 reduction contributing to pulmonary EMT may involve in the process of Cd-induced COPD.

Associations between blood cadmium and endocrine features related to PCOS-phenotypes in healthy women of reproductive age: a prospective cohort study

BACKGROUND

Cadmium is an endocrine disrupting chemical that affects the hypothalamic-pituitary-gonadal axis. Though evidence suggests its potential role in altering androgen synthesis and metabolic pathways that are characteristic of polycystic ovary syndrome (PCOS), its relation in healthy women of reproductive age is largely unknown. As women with mild sub-clinical features of PCOS who do not meet the diagnostic criteria of PCOS may still experience reduced fecundability, investigating associations between cadmium and PCOS-phenotypes among healthy women may provide unique insight into the reproductive implications for many on the PCOS spectrum. Therefore, the objective of this study was to evaluate associations between cadmium and androgens, anti-Müllerian hormone (AMH), and metabolic markers in women of reproductive age.

METHODS

This was a prospective cohort study of 251 healthy premenopausal women without self-reported PCOS (mean age 27.3 years and BMI 24.1 kg/m²). Cadmium was measured in blood collected at baseline. Reproductive hormones and metabolic markers were measured in fasting serum 8 times per menstrual cycle for 2 cycles. Linear mixed models and Poisson regression with a robust error variance were used to examine associations between cadmium and reproductive hormones and metabolic markers and anovulation, respectively.

RESULTS

Median (interquartile range) blood cadmium concentrations at baseline were 0.30 (0.19-0.43) µg/L. Higher levels of testosterone (2.2 %, 95 % confidence interval [CI] 0.4, 4.1), sex hormone-binding globulin (2.9 %, 95 % CI 0.5, 5.5), and AMH (7.7 %, 95 % CI 1.1, 14.9) were observed per 0.1 µg/L increase in cadmium concentrations. An 18 % higher probability of a mild PCOS-phenotype (95 % CI 1.06, 1.31), defined by a menstrual cycle being in the highest quartile of cycle-averaged testosterone and AMH levels, was also found per 0.1 µg/L increase in cadmium levels. No associations were observed for insulin and glucose. These findings were consistent even after analyses were restricted to non-smokers or further adjusted for dietary factors to account for potential sources of exposure.

CONCLUSIONS

Overall, among healthy reproductive-aged women, cadmium was associated with endocrine features central to PCOS, but not with metabolic markers. These suggest its potential role in the hormonal milieu associated with PCOS even at low levels of exposure.

High levels of metals/metalloids in blood and urine of residents living in the area affected by the dam failing in Barra Longa, District, Brazil: A preliminary human biomonitoring study

Fundão mining tailings dam in Mariana District has collapsed in 2015 and caused the biggest environmental disaster in Brazil. Barra Longa District had its urban area invaded by toxic sludge and its population was extensively exposed to it. Blood and urine samples were collected from 11 residents, focused on investigating the presence of metals at the end of an exploratory health study in 507 inhabitants in 2016. Results have shown increased levels of aluminum, arsenic, cadmium, cooper, lead, manganese and nickel, and zinc defficiency in their body, as well as clinical outcomes.

Lead (Pb) exposure is associated with changes in the expression levels of circulating miRNAS (miR-155, miR-126) in Mexican women

The environmental contamination with lead (Pb) is considered a critical issue worldwide. Therefore, this study aimed to evaluate the expression levels of circulating miRNAs (miR-155, miR-126, and miR-145) in Mexican women exposed to Pb. Blood lead levels (BLL) were assessed in enrolled women (n = 190) using an atomic absorption method. Also, serum miRNAs expression levels were quantified through a real-time PCR assay. A mean BLL of 10.5 ± 4.50 μg/dL was detected. Overexpression of miR-155 was detected in highly exposed women. Besides, a significant simple positive relationship (p < 0.05) was found between BLL and serum miR-155 expression levels. Additionally, a significant inverse correlation (p < 0.05) was determined between BLL and serum miR-126 expression levels, as downregulation of miR-126 expression levels was observed in highly exposed women. The findings in this study are the concern, as epigenetic changes detected may represent a connection between health illnesses and Pb exposure.

The association between life-time dietary cadmium intake from rice and chronic kidney disease

The association between internal cadmium exposure and chronic kidney disease (CKD) has been investigated before. However, few studies have shown the association between dietary cadmium intake and CKD. In this study, we show the association between life-time dietary cadmium intake and CKD based on a follow-up study. At baseline, we collected blood and urine samples for assays of cadmium and renal effect biomarkers. A questionnaire and food survey was given to each subject to collect diet and lifestyle information for the estimation of cadmium intake. Dietary cadmium, cadmium in blood and urine were regarded as exposure markers. Life-time dietary cadmium intake was estimated based on an individual's daily cadmium intake and exposure time. At follow-up, 467 persons (163 men and 304 women) were finally included. CKD at follow-up was considered if the estimated glomerular filtration rate (eGFR) was less than 60 mL/min/1.73 m². The eGFR level in subjects in the highest quartile of total dietary cadmium intake (>9.34 g) was significantly lower than in those with a moderate or low intake (p < 0.01). eGFR was negatively associated with total dietary cadmium intake (β = -0.42, 95% confidence interval (CI): -0.77 to -0.07) after adjustment with confounders. Logistic regression further showed that the risk of CKD in subjects with a high total dietary cadmium intake (>2.2 g) was higher than in those with a low intake (odds ratio (OR) = 18.16, 95%CI: 1.75-188.85). A similar association was found between the baseline urinary albumin (UALB) level and CKD incidence. A predictive model based on UALB and life-time dietary cadmium intake showed an acceptable performance (the area under the curve was 0.77 (95%CI: 0.65-0.88)). Our data show that high dietary cadmium exposure was associated with CKD after controlling for renal tubular dysfunction and internal cadmium exposure.

Association of environmental cadmium exposure and bone remodeling in women over 50 years of age

Chronic cadmium (Cd) toxicity is a significant health concern, and the mechanism of long-term low-dose Cd exposure on bone has not been fully elucidated yet. This study aimed to assess the association between long-term environmental Cd exposure and bone remodeling in women who aged over 50. A total of 278 non-smoking subjects from Cd-polluted group (n = 191) and non-Cd polluted group (n = 87) were investigated. Bone mineral density (BMD), the levels of three bone turnover markers (BTMs), including total procollagen type 1 amino-terminal propeptide (P1NP), collagen type 1 cross-linked C-telopeptide (β-CTX), bone-specific alkaline phosphatase (BALP), together with serum soluble receptor activator of nuclear factor-κB ligand (sRANKL) and osteoprotegerin (OPG) were determined. Early markers of renal dysfunction were measured as well. Urinary Cd concentrations ranged from 0.41 to 87.31 μg/g creatinine, with a median of 4.91 μg/g creatinine. Age, BMD, T-score, and prevalence of osteoporosis showed no statistical differences among the quartiles of urinary Cd concentrations, while serum levels of P1NP, β-CTX, and OPG were higher in the upper quartiles. Multivariate linear regression models indicated significantly positive associations of urinary Cd concentration with serum levels of P1NP, β-CTX, BALP, sRANKL, and OPG. A ridge regression analysis with T-score and the three BTMs, sRANKL, and OPG, adjusted for age and body mass index (BMI), indicated that except for age and Cd exposure, β-CTX was a predictor of T-score. These findings demonstrated that Cd may directly accelerate bone remodeling. Serum β-CTX might be an appropriate biochemical marker for evaluating and monitoring Cd-related bone loss. Capsule: Cadmium (Cd) may directly accelerate bone remodeling and serum β-CTX is a valuable biochemical marker for evaluating Cd-related bone loss.

Lead Poisoning in South African Children: The Hazard is at Horne

Lead is a toxic heavy metal that has been used extensively in modern society, causing widespread environmental contamination even in isolated parts of the world. Irrefutable evidence associates lead at different exposure levels with a wide spectrum of health and social effects, including mild intellectual impairment, hyperactivity, shortened concentration span, poor school performance, violent/aggressive behavior, and hearing loss. Lead has an impact on virtually all organ systems, including the heart, brain, liver, kidneys, and circulatory system, resulting in coma and death in severe cases. In recent years, a consensus was reached regarding the absence of a threshold for the key health effects associated with lead exposure and the permanent and irreversible nature of many health and social consequences of lead exposure. The public health problem of environmental lead exposure has been widely investigated in developed countries like the United States of America, where actions taken have led to significant reductions in children's blood lead concentrations. In contrast, there is a relative dearth of information and action regarding lead poisoning in developing countries, particularly in African countries, despite evidence of widespread and excessive childhood lead exposure. In this paper, we will review the information from available published papers, the 'grey Literature', and unpublished reports to give an overview of lead exposure in South African children over the past two decades, with particular emphasis on sources of exposure in the home environment.

Per- and Polyfluoroalkyl Substances in Human Serum Samples of Selected Populations from Ghana

The aims of this study were to assess serum concentrations of per- and polyfluoroalkyl substances (PFASs) in selected populations from Ghana, including workers engaged in the repair of electronic equipment (ERWs), and to elucidate PFAS concentrations in relation to blood mercury concentrations (B-Hg) as a biomarker of seafood consumption. In all, 219 participants were recruited into the study, of which 26 were women and 64 were ERWs. Overall, the PFAS concentrations were low. The most abundant components were perfluorooctane sulfonate (PFOS) and perfluorohexane sulfonic acid (PFHxS). Women had generally lower PFAS concentration than men. The ERWs had statistically significantly higher concentrations of perfluorooctanoate (PFOA), which was associated with the concentration of tin in urine. This could indicate exposure during soldering. The concentration of B-Hg was associated with several of the PFASs such as PFOA, PFOS and perfluoroheptane sulfonate (PFHpS). Additionally, the concentrations of perfluorodecanoic acid (PFDA) and perfluoroundecanoate (PFUnDA) were highly associated with the concentrations of B-Hg. It is noteworthy that the linear isomer of PFHxS was strongly associated with B-Hg while the branched isomers of PFHxS were not. In conclusion, the PFAS concentrations observed in the present study are low compared to other populations previously investigated, which also reflects a lower PFAS exposure within the Ghanaian cohorts. ERWs had significantly higher PFOA concentrations than the other participants. Several PFASs were associated with B-Hg, indicating that seafood consumption may be a source of PFAS exposure.

Multi-residue analysis of pesticides in blood plasma using hollow fiber solvent bar microextraction and gas chromatography with a flame ionization detector

The challenges faced on pesticide extraction from biological samples are finding a method that allows a multi-residue extraction, pre-concentration, clean-up, and isolation of analytes in just one step. In this sense, the hollow fiber - liquid phase microextraction method (HF- LPME) in the "solvent bar" mode was used to optimize and validate a method for pesticide multi-residue analysis in blood plasma at trace levels, through gas chromatography coupled with a flame ionization detector (GC-FID). Hollow fiber solvent bar microextraction HF-SBME was carried out with octanol immobilized into the pores of hydrophobic polypropylene fiber and disposed within a matrix of blood plasma, spiked with a mixture of pesticides (monocrotophos, lindane, aldrin, methyl parathion, endosulfan, dieldrin, DDD, DDT, and endrin). The optimization parameters evaluated were: extraction temperature and time, stirring speed, and salt concentration. A principal component analysis was performed to visualize the analytes' behaviour based on their explained variance, and then, a Box-Behnken analysis was generated to identify the optimum parameters. According to the PCA, all pesticides showed similar responses to the extraction method and the response of dieldrin exhibit the lowest variance. Moreover, the stationary points selected from the Box-Behnken analysis were 25.5 °C for the extraction temperature, 870 rpm for stirring speed, 16 min for extraction time, and 8.3 % w/v of salt concentration. Moreover, the validation results proved that HF-SBME is an alternative technique for pesticide multi-residue extraction in blood plasma. The analytes were able to concentrate, reaching 46 fold enrichment. The solvent type, sample and solvent volume were narrowed down without changing the method's precision or accuracy. The relative standard deviation was under 10 %, and the recovery was between 55 % and 105 % for the different analytes excepting lindane, which had lower recovery (27 %). The detection limits were 0.02 until 0.13 μg mL^-1 for most of the pesticides used. Finally, HF-SBME is a good alternative for pesticide multi-residue extraction in complex matrices like plasma.

The association between perfluoroalkyl substances and lipid profile in exposed pregnant women in the Veneto region, Italy

BACKGROUND

Residents of a large area of North-Eastern Italy were exposed for decades to high concentrations of perfluoroalkyl and polyfluoroalkyl substances (PFAS) via drinking water. Serum PFAS levels have been consistently associated with elevated serum lipids, but few studies have been conducted among pregnant women, and none has stratified analyses by trimester of gestation. Elevated serum lipid levels during pregnancy can have both immediate and long-lasting effects on pregnant women and the developing fetus. We evaluated the association between perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), and perfluoro-hexanesulfonate (PFHxS) levels in relation to lipid profiles in highly-exposed pregnant women.

METHODS

A cross-sectional analysis was conducted in 319 pregnant women (age 14-48 years) enrolled in the Regional health surveillance program. Non-fasting blood samples were obtained in any trimester of pregnancy and analyzed for PFOA, PFOS and PFHxS, total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C). Low-density lipoprotein cholesterol (LDL-C) was calculated. The associations between ln-transformed PFAS (and categorized into quartiles) and lipids were assessed using generalized additive models. Analyses were adjusted for potential confounders and stratified according to pregnancy trimester.

RESULTS

The geometric means of PFOA, PFOS and PFHxS were 14.78 ng/mL, 2.67 ng/mL and 1.89 ng/mL, respectively. The plasma levels of TC, HDL-C and LDL-C increased steadily throughout the trimesters. In the 1st trimester, PFOS was positively associated with TC and PFHxS with HDL-C. In the 3rd trimester, instead, an inverse relationship was seen between PFOA and PFHxS and both TC and LDL-C.

CONCLUSIONS

Results suggest the associations between PFAS concentrations and lipid profiles in pregnant women might differ by trimesters of pregnancy. In the first trimester, patterns are similar to those of non-pregnant women, while they differ late in pregnancy. Different independent behavior of PFAS and lipid levels throughout the pregnancy might explain our observations. These findings support the ubiquitous exposure to PFAS and possible influence on lipid metabolisms during pregnancy and suggest a careful evaluation of the timing of PFAS measurement, when examining effects of PFAS during pregnancy on gestational outcomes related to serum lipids amounts.

Associations of Maternal Stress, Prenatal Exposure to Per- and Polyfluoroalkyl Substances (PFAS), and Demographic Risk Factors with Birth Outcomes and Offspring Neurodevelopment: An Overview of the ECHO.CA.IL Prospective Birth Cohorts

BACKGROUND

Infants whose mothers experience greater psychosocial stress and environmental chemical exposures during pregnancy may face greater rates of preterm birth, lower birth weight, and impaired neurodevelopment.

METHODS

ECHO.CA.IL is composed of two cohorts, Chemicals in Our Bodies (CIOB; n = 822 pregnant women and n = 286 infants) and Illinois Kids Development Study (IKIDS; n = 565 mother-infant pairs), which recruit pregnant women from San Francisco, CA and Urbana-Champaign, IL, respectively. We examined associations between demographic characteristics and gestational age, birth weight z-scores, and cognition at 7.5 months across these two cohorts using linear models. We also examined differences in biomarkers of exposure to per- and polyfluoroalkyl substances (PFAS), measured in second-trimester serum, and psychosocial stressors by cohort and participant demographics.

RESULTS

To date, these cohorts have recruited over 1300 pregnant women combined. IKIDS has mothers who are majority white (80%), whereas CIOB mothers are racially and ethnically diverse (38% white, 34% Hispanic, 17% Asian/Pacific Islander). Compared to CIOB, median levels of PFOS, a specific PFAS congener, are higher in IKIDS (2.45 ng/mL versus 1.94 ng/mL), while psychosocial stressors are higher among CIOB. Across both cohorts, women who were non-white and single had lower birth weight z-scores relative to white women and married women, respectively. Demographic characteristics are not associated with cognitive outcomes at 7.5 months.

CONCLUSIONS

This profile of the ECHO.CA.IL cohort found that mothers and their infants who vary in terms of socioeconomic status, race/ethnicity, and geographic location are similar in many of our measures of exposures and cognitive outcomes. Similar to past work, we found that non-white and single women had lower birth weight infants than white and married women. We also found differences in levels of PFOS and psychosocial stressors based on geographic location.

Serum levels of novel brominated flame retardants (NBFRs) in residents of a major BFR-producing region: Occurrence, impact factors and the relationship to thyroid and liver function

Five currently used novel brominated flame retardants (NBFRs) were determined in 172 serum samples collected from nonoccupational residents of a major BFR-producing region. All the 5 NBFRs presented high detection frequencies (DFs, >90%), and decabromodiphenyl ethane (DBDPE), a substitute of decabrominated diphenyl ethers (deca-BDE), was the most abundant NBFR. The levels of DBDPE were from <LOD to 1590 ng/g lw, with a median level of 32.5 ng/g lw. The median levels of other NBFRs were from 0.134 to 2.87 ng/g lw, which were at least 10 times lower than that of DBDPE. Moreover, a comparison to other studies showed that our results were significantly higher than studies conducted in background population. The levels of some NBFRs adjusted by serum lipid showed negative and significant correlation with BMI, whereas the difference disappeared when NBFRs levels were calculated based on serum volume. Certain NBFRs in female showed significantly higher concentrations than those in male. No significant effect of age, smoking habit, education level and children birth (in female) on serum NBFR levels was observed. The relationship between the serum levels of NBFRs and a series of thyroid/liver injury biomarkers was further analyzed to evaluate the health effects of these NBFRs to human being. Results showed that a 10-fold increment in the serum DBDPE level was associated with decreased total triiodothyronine (TT3) level (-0.037 nmol/L) [95% CI: -0.070, -0.003]， whereas serum pentabromoethylbenzene (PBEB) level was associated with increased total triiodothyronine (TT3) level (0.031 nmol/L) [95% CI: 0.001, 0.060]. For liver indicators, a 10-fold increment in the serum level of PBT was associated with decreased Ln aspartate aminotransferase/alanine aminotransferase (AST/ALT) level (-0.068) [95% CI: -0.129, -0.007]. A 10-fold increment in the serum level of BTBPE was associated with increased TBIL level (0.869 μmol/L) [95% CI: 0.175, 1.564], direct bilirubin (DBIL) level (0.231 μmol/L) [95% CI: 0.075, 0.388] and IDBIL level (0.638 μmol/L) [95% CI: 0.091, 1.185]. Our findings indicate that BFR production is posing heavy BFR contamination to surrounding environment and human being, and which might relate to thyroid disruption and liver injury.

Polyfluoroalkyl chemicals and the risk of kidney stones in US adults: A population-based study

The potential nephrotoxicity of polyfluoroalkyl chemicals (PFCs) have received extensive attention. However, the relationship between PFCs and the risk of kidney stones remain unclear. This study aimed to examine the level of PFCs in the US population and its relationship with the risk of kidney stones. We investigated the serum levels of six PFCs in 8453 adult participants (≥20 years) from the National Health and Nutrition Examination Survey (NHANES) between 2007 and 2016, including perfluorodecanoic acid (PFDE), perfluorohexane sulfonic acid (PFHS), 2-(N-methyl-perfluorooctane sulfonamido) acetate (MPAH), perfluorononanoic acid (PFNA), perfluoroundecanoic acid (PFUA), and perfluorododecanoic acid (PFDO). Logistic regression model was used to evaluate the correlation between PFCs and kidney stones. Of the 8453 participants, 787 self-reported a history of kidney stones. After adjusting for gender, age, race, education, marital status, body mass index (BMI), hypertension, diabetes and estimated glomerular filtration rate (eGFR), we found that total PFCs and PFHS were positively correlated with the risk of kidney stones. Compared with the lowest tertile, the odds ratios with 95% confidence intervals (CI) with increasing tertiles were 1.30 (95% CI,1.08-1.59, p = 0.007) and 1.25 (95 CI%,1.00-1.52, p = 0.024) for total PFCs and 1.24 (95 CI%,1.03-1.51, p = 0.032), and 1.35 (95 CI,1.10-1.68, p = 0.005) for PFHS. Our study shows that total PFCs and PFHS were associated with an increased risk of kidney stones.

Plasma titanium level is positively associated with metabolic syndrome: A survey in China's heavy metal polluted regions

OBJECTIVE

Several heavy metals have been reported to be associated with metabolic syndrome(MetS) in general population, while effects of multiple metals exposure on MetS in residents living in heavy metal polluted regions have not been investigated. We aimed to assess the association of 23 metal levels and MetS among population living in China's heavy metal polluted regions.

METHODS

From August 2016 to July 2017, a total of 2109 eligible participants were consecutively enrolled in our study in Hunan province, China. The levels of plasma and urine metals were measured by inductively coupled plasma mass spectrometer (ICP-MS). MetS was defined by the criteria of the International Diabetes Federation. Multivariable regression models were applied to analysis the potential relationship.

RESULTS

In the overall population, crude model showed positive relationship of plasma titanium (Ti) with MetS and negative association of urine vanadium, iron, and selenium with MetS. After adjusted for potential confounders, only plasma Ti was positive associated with MetS (adjusted OR for Q4 versus Q1: 1.46; 95% CI: 1.06-1.99), and this positive correlation was explained by abdominal obesity (OR = 1.84, 95% CI: 1.41-2.39) and high triglycerides (OR = 2.23, 95% CI: 1.68-2.96). Further linear regression analysis revealed significant association of plasma Ti levels with waist circumference (β = 0.0056, 95% CI: 0.0004-0.0109, P = 0.036) and triglycerides (β = 0.0012, 95% CI: 0.0006-0.0019, P < 0.001), respectively.

CONCLUSION

High plasma Ti level was associated with increased risk of MetS via increasing waist circumference and triglycerides in people under high metal exposure.

Gestational perfluoroalkyl substance exposure and body mass index trajectories over the first 12 years of life

BACKGROUND/OBJECTIVES

Gestational exposure to perfluoroalkyl substances (PFAS), a ubiquitous class of persistent endocrine disrupting chemicals, is associated with increased risk of obesity and cardiometabolic disease. However, it is unclear if gestational PFAS exposure is associated with adiposity trajectories related to adult obesity and cardiometabolic health.

SUBJECTS/METHODS

We measured perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), perfluorononaoic acid, and perfluorohexanesulfonic acid (PFHxS) concentrations in maternal serum collected between 16 weeks gestation and delivery in a cohort of 345 mother-child pairs in Cincinnati, OH (enrolled 2003-06). From age 4 weeks to 12 years, we measured weight and length or height up to eight times and calculated child body mass index (BMI) (1865 repeated measures). Using covariate-adjusted linear mixed models and splines to account for repeated BMI measures and nonlinear BMI patterns, respectively, we estimated the age/magnitude of infancy BMI zenith (~1 year) and childhood BMI nadir (~5 years), BMI accrual from 8 to 12 years, and BMI at age 12 years by PFAS terciles.

RESULTS

BMI trajectories varied by PFOA concentrations (age × PFOA interaction p value = 0.03). Children born to women with higher PFOA concentrations had lower infancy and early childhood BMI, earlier BMI nadir, accelerating BMI gains in mid-childhood and adolescence, and higher BMI at age 12 years. Some of these associations were non-monotonic. PFOS and PFHxS were not associated with alterations in BMI trajectories, but were monotonically associated with lower BMI across infancy, childhood, and adolescence. Compared to children in the first PFOS tercile, those in the second (β: -0.83; 95% confidence interval (CI): -2.11, 0.51 kg/m2), and third (β: -1.41; 95% CI: -2.65, -0.14 kg/m2) had lower BMI at age 12 years.

CONCLUSIONS

These results suggest that gestational PFOA exposure may be associated with BMI trajectories related to adult obesity and cardiometabolic disease, while PFOS and PFHxS exposure is associated with lower BMI in the first 12 years of life.

Co-exposure of serum calcium, selenium and vanadium is nonlinearly associated with increased risk of type 2 diabetes mellitus in a Chinese population

BACKGROUND

Metals play an important role in type 2 diabetes mellitus (T2DM). This study aimed to explore the association of T2DM risk with single metal exposure and multi-metal co-exposure.

METHODS

A case-control study with 223 T2DM patients and 302 controls was conducted. Serum concentrations of 19 metals were determined by inductively coupled plasma mass spectrometry (ICP-MS). Those metals with greater effects were screened out and co-exposure effects of metals were assessed by least absolute shrinkage and selection operator (LASSO) regression.

RESULTS

Serum calcium (Ca), selenium (Se) and vanadium (V) were found with greater effects. Higher levels of Ca and Se were associated with increased T2DM risk (OR = 2.23, 95%CI: 1.38-3.62, P_trend = 0.002; OR = 3.16, 95%CI: 1.82-5.50, P_trend < 0.001), but higher V level was associated with decreased T2DM risk (OR = 0.58, 95%CI: 0.34-0.97, P_trend < 0.001). Serum Ca and V concentrations were nonlinearly associated with T2DM risk (P_overall < 0.001, P_nonliearity < 0.001); however, Se concentration was linearly associated with T2DM risk (P_overall < 0.001, P_nonliearity = 0.389). High co-exposure score of serum Ca, Se and V was associated with increased T2DM risk (OR = 3.50, 95%CI: 2.08-5.89, P_trend < 0.001) as a non-linear relationship (P_overall < 0.001, P_nonliearity = 0.003).

CONCLUSIONS

This study suggest that higher levels of serum Ca and Se were associated with increased T2DM risk, but higher serum V level was associated with decreased T2DM risk. Moreover, co-exposure of serum Ca, Se and V was nonlinearly associated with T2DM risk, and high co-exposure score was positively associated with T2DM risk.

Blood lead and cadmium levels in occupationally exposed workers and their effect on markers of DNA damage and repair

Occupational exposure to heavy metals like lead and cadmium causes a wide range of biological effects and may elevate the risk of genetic damage. Heavy metal toxicity is now becoming a significant public health problem. There are many discrepancies in the results of the studies on the genotoxicity of heavy metals. Therefore, the study aimed to estimate lead, cadmium, and 8-OHdG levels (8-hydroxy-2-deoxyguanosine) and expression of DNA repair gene OGG1 (8-oxoguanine DNA glycosylase 1) in occupationally heavy metal exposed workers. The study comprised 100 workers, occupationally exposed to lead and cadmium from different factories and 100 controls without history of metal exposure. The lead and cadmium mean ± SD were 5.69 ± 12.07 µg/dL and 3.44 ± 1.33 µg/L in the cases and 1.27 ± 1.10 µg/dL and 1.07 ± 0.67 µg/L in the controls. The 8-OHdG concentration was significantly higher in the cases than the controls. Cadmium showed a significant positive correlation with 8-OHdG in the cases. The expression of OGG1 was significantly down-regulated in the cases compared to the controls. Lead levels did not show any significant correlation with OGG1, whereas cadmium level had a significant positive correlation with OGG1 in the cases. To conclude, the exposure to heavy metals is associated with increased oxidative DNA damage and impaired expression of the DNA repair gene, OGG1.

Exposure to Perfluoroalkyl Substances During Pregnancy and Fetal BDNF Level: A Prospective Cohort Study

BACKGROUND

Humans are widely exposed to environmental perfluoroalkyl substances (PFAS), which may affect fetal neurodevelopment. Brain-derived neurotrophic factor (BDNF) is an important factor in neurodevelopment, but its role in PFAS-induced neurotoxicity is unclear. We investigated the association between prenatal PFAS exposure and fetal BDNF level in the umbilical cord blood in a large prospective cohort.

METHODS

A total of 725 pregnant women who participated in the Shanghai Birth Cohort were included. 10 PFAS were measured by high-performance liquid chromatography/tandem mass spectrometry (HPLC/MS-MS) in the plasma samples of early pregnancy. The BDNF level was determined by ELISA. The concentration of total mercury (Hg) in the umbilical cord blood was tested by cold vapor atomic absorption spectrometry (AAS) and included as a main confounder, along with other covariates. Multiple linear regression was used to explore the associations between PFAS concentrations and BDNF level. Quantile-based g-computation was applied to explore the joint and independent effects of PFAS on BDNF level.

RESULTS

The mean BDNF level in the total population was 10797 (±4713) pg/ml. Male fetuses had a higher level than female fetuses (P<0.001). A significant positive association was observed between PFHxS and BDNF level after adjusting for potential confounders [β=1285 (95% CI: 453, 2118, P=0.003)]. No association was observed between other PFAS congeners and BDNF level. Results of the mixed exposure model showed that the joint effects of PFAS mixture were not associated with BDNF [β=447 (95% CI: -83, 978, P=0.10)], while the positive association with PFHxS exposure remained significant after controlling for other PFAS [β=592 (95% CI: 226, 958, P=0.002)]. The above associations were more prominent in male [β=773 (95% CI: 25, 1520, P= 0.04)] than female fetuses [β=105 (95% CI: -791, 1002, P= 0.82)] for the mixed effects.

CONCLUSIONS

Prenatal exposure to PFHxS was associated with an increased BDNF level in the umbilical blood, especially in male fetuses.

Integration of biomonitoring data and reverse dosimetry modeling to assess population risks of arsenic-induced chronic kidney disease and urinary cancer

Chronic exposure to inorganic arsenic (iAs) is associated with chronic kidney disease (CKD) and urinary cancer, but the risks are poorly understood. Human biomonitoring can serve as a tool to better quantify human exposure and to conduct risk assessment. We aimed to assess the population risks of CKD and urinary cancer due to iAs intake based on the blood arsenic concentrations of 601 participants in Taiwan. A physiologically based pharmacokinetic modeling-based reverse dosimetry was conducted to estimate the daily intakes of iAs (DI_iAs). We performed the benchmark dose (BMD) modeling for CKD using participants' estimated glomerular filtration rate (eGFR) and the estimated DIiAs to derive a point of departure (POD). Margin of exposure (MOE) was used to characterize the risks. The population with eGFR values of <60 mL/min/1.73 m² had significantly higher DI_iAs (median: 3.20 μg/kg/day, 2.5th-97.5th percentiles: 2.35-4.67 μg/kg/day) than those with normal renal function (1.99, 1.22-3.42 μg/kg/day). The POD for CKD was 1.557 μg/kg/day, which could serve as a possible reference value for CKD risk assessment. The MOEs indicated that the CKD risk due to iAs intake may potentially be a cause for high concern for the population with reduced renal function. The iAs-induced urinary cancer risk may be a cause for moderate-to-high concern.

Association of aldehyde exposure with cardiovascular disease

The effect of aldehyde exposure on the cardiovascular system remains unclear. The objective of this study was to determine whether aldehyde exposure is associated with the prevalence of cardiovascular disease (CVD). We analyzed associations between aldehydes and CVD using data from 1962 adult participants in the National Health and Nutrition Examination Survey (NHANES) from 2013 to 2014. Multivariable logistic regression and restricted cubic spline models were used to examine the association between aldehydes and CVD. The prevalence of CVD was 10.3%. After adjusting for confounding factors, including age, sex, education level, race, diabetes mellitus, smoking, alcohol use, hypertension, body mass index, the poverty-income ratio, physical activity, energy intake, high-density cholesterol (HDL) and low-density cholesterol (LDL), compared with the lowest quartiles, the odds ratios (ORs) with 95% confidence intervals (CIs) for CVD across the quartiles were 0.52 (0.31, 0.87), 0.73 (0.43, 1.22), and 1.13 (0.68, 1.86) for benzaldehyde and 1.48 (0.87, 2.52), 1.70 (1.01, 2.92), and 2.13 (1.19, 3.86) for isopentanaldehyde. There was no significant association between other aldehydes and CVD. The restricted cubic spline plot showed a J-curve relationship between benzaldehyde and CVD. The inflection point for the curve was found at a benzaldehyde level of 0.98 ng/ml. The ORs (95% CIs) for CVD were 0.51 (0.31, 0.86) and 1.58 (1.15, 2.17) on the left and right sides of the inflection point, respectively. Our results demonstrate a J-curve relationship between benzaldehyde and CVD. Isopentanaldehyde is positively associated with CVD. Further study is warranted to verify this association and to elucidate its underlying mechanisms.

Concentration of polychlorinated biphenyls in serum from New Jersey biomonitoring study: 2016-2018

The first statewide New Jersey Biomonitoring (NJBM) of serum polychlorinated biphenyls (PCBs) was conducted from 2016 to 2018. Forty ortho-substituted PCBs were measured in serum samples collected from 920 NJ residents in compliance with the CDC method. The lipid adjusted geometric mean (GM) of ∑₄₀PCB concentration for all the 920 measured subjects was 65.5 ng/g lipid (95% CIs: 56.9-75.4 ng/g lipid). Age stratified serum concentration showed that the lowest GM (33.3 ng/g lipid) was observed in the 20-39 years age group (n = 282), followed by a concentration of 76.05 ng/g lipid (n = 382) in the 40-59 years age group, and the highest GM (168.4 ng/g lipid) was found in the 60-74 years age group (n = 256). A survey regression model revealed that ∑₄₀PCBs was significantly associated with age, moderately associated with geographic region, and not significantly associated with sex. The comparison of serum PCB levels in NJBM with the sequential National Health and Nutrition Examination Survey (NHANES) data suggested that the serum PCBs in NJ adults declined 52-59% at all age groups over the last decade. Positive Matrix Factorization (PMF) suggests that ongoing and recent exposure to lower molecular weight PCBs contributes about 15% to total serum PCB levels and more in younger subjects, while higher molecular weight PCBs contribute 52% of the total serum PCB levels and more in older subjects.

Accumulation of trace metals in eggs and hatchlings of Chelonia mydas

BACKGROUND

The objective of this study was to verify the accumulation of trace metals in eggs and hatchlings of Chelonia mydas, evaluating if metal accumulation is originated from maternal transfer and/or from the incubation environment. Other assessments were also performed, as metal distribution in different tissues (blood, kidney, liver, muscle, and turtle shells) of newly hatched turtles, and genotoxic analysis, to verify possible damages caused by the presence of metals.

METHODS

The assessments were carried out by quantifying Cd, Ni, Pb, Mn and Fe in egg sample collected during laying time (eggshells (ELT) and egg content (EC)), eggshells from newly hatched turtles (ENH), hatchlings tissues (H - blood, kidney, liver, muscle, and shell)) (n = 18 for each biological sample - 3 of each nest) and nest sediments (n = 6, one of each nest). Comparative analysis were made between ELT and ENH, as well as between egg content (EC) and the sum of tissue samples from hatchlings, using Mann-Whitney hypothesis test (p < 0,05). The amount of metals in different hatchling was quantified and followed by the Dunn post-test. A principal component analysis (PCA) was also employed.

RESULTS

Metals studied were found in all investigated samples. The concentration of a great amount of investigated metals was significantly higher (P=<0.001) in eggshells from ENH than in ELT. An increase in Cd (2.16-fold), Pb (3.47-fold), Fe (6.83-fold) and Mn (195.57-fold) concentration was noticed in ENH. We also observed an increase in Fe (1.59-fold), Mn (1.74-fold) and Ni (1.59-fold) concentration in hatchling, when compared with EC, due to transfer from nest sediments. In relation to the hatchling's tissues, blood was shown to accumulate higher concentrations of Ni and Pb, while shells accumulated more Cd and Fe, and Mn is more associated with liver and kidney. Fe was the highest accumulated metal in both tissues, and muscles presented discrete concentrations of Ni, Mn, and Pb. A mean concentration of 1.25‰ MN was obtained in C. mydas hatchlings, indicating that the accumulation of metals in hatchlings didn't cause toxicology effects.

CONCLUSION

Hatchlings accumulate metals through the maternal and sediment transfer, although the levels of metal accumulation were not enough to cause genotoxic damage.

Polychlorinated biphenyls (PCBs) and risk of dementia and Parkinson disease: A population-based cohort study in a North Italian highly polluted area

BACKGROUND

Serum polychlorinated biphenyls (PCBs) have been associated with some chronic diseases, but little evidence exists on their possible relationship with neurodegenerative diseases. We aimed to assess the relationship between PCB exposure and the occurrence of dementia and Parkinson disease in a prospective cohort study in a highly polluted area (Brescia-Caffaro).

METHODS

PCB exposure was assessed by measuring serum levels of 24 congeners. Data on the onset of dementia and Parkinson disease were retrieved by the Brescia Health Protection Agency Database. We used Poisson regression models adjusted for possible confounders to calculate rate ratios (RRs). A mediation analysis was performed to evaluate the mediatory role of cardiovascular diseases.

RESULTS

699 subjects without neurologic diseases at baseline were enrolled (48.1% males, 63.2 years of mean age) in 2001-2013 and followed up to 2018. During a mean follow-up of 8.8 years, 36 and 20 subjects developed dementia and Parkinson disease. Subjects in the 2nd and 3rd tertiles of the total PCBs distribution, compared with those in the 1st tertile, had a higher risk of dementia (RR = 2.30 and RR = 4.35). The estimates for Parkinson disease included the null value with wide confidence intervals. In the mediation analysis, the association between PCB exposure and dementia was dominated by the direct pathway and not by the hypertension-mediated pathway.

CONCLUSIONS

We observed a positive association between total PCBs serum levels and the onset of dementia not mediated by hypertension. For Parkinson, the unstable risk estimates did not allow to draw a conclusion on a possible association.

Serum levels of per- and polyfluoroalkyl substances alternatives and blood pressure by sex status: Isomers of C8 health project in China

Several in vitro and in vivo studies have demonstrated the toxicity of perfluoroalkyl and polyfluoroalkyl substances (PFASs) alternatives, however, relevant epidemiological findings remain to be performed. In addition, the association between PFASs alternatives and blood pressure has not been explored. To address this gap, we quantified serum levels of alternatives and legacy PFAS in 1273 healthy Chinese, aged 34-94 years, from "isomers of C8 health project". Our results showed that an increase of serum PFASs levels was correlated with elevated blood pressure and higher prevalence of hypertension: per natural log unit (ng/mL) increase of 6:2 chlorinated polyfluorinated ether sulfonic acids (Cl-PFESA) elevated 1.31 (95%CI: 0.13, 2.50) mmHg of diastolic pressure (DBP). Adjusted odds ratios (aORs) for hypertension with per natural log increase of 6:2 and 8:2 Cl-PFESA were 2.57 (95%CI: 1.86, 3.56) and 1.18 (95%CI: 1.06, 1.32), respectively. When stratified by sex, the effects of PFASs alternatives on increased blood pressure and hypertension were stronger in women. Meanwhile, the association between 6:2 Cl-PFESA (aOR = 6.81; 95%CI: 3.54, 13.09) and hypertension was stronger than perfluorooctanoic acid (PFOA) (aOR = 2.32, 95%CI: 1.38, 3.91) in women. In conclusion, our pilot study demonstrates that serum concentrations of PFASs alternatives are positively associated with blood pressure. Moreover, women seem to be more susceptible, and alternatives exhibited stronger effects than legacy PFASs.

Environmental Cadmium and Mortality from Influenza and Pneumonia in U.S. Adults

BACKGROUND

Environmental cadmium exposure is widespread. In humans, cadmium is poorly excreted, triggers pulmonary inflammation, reduces pulmonary function, and enhances lung injury by respiratory syncytial virus.

OBJECTIVES

We examined the association of cadmium burden with mortality related to influenza or pneumonia.

METHODS

This prospective analysis of the National Health and Nutrition Examination Survey (NHANES) included 7,173 and 8,678 participants ≥ 45 years of age enrolled in NHANES-III and NHANES 1999-2006, respectively. Associations were evaluated between cadmium and mortality from influenza or pneumonia during a median follow-up of 17.3 y (NHANES-III, based on creatinine-corrected urine cadmium) and 11.4 y (NHANES 1999-2006, based on blood cadmium). Survey-weighted Cox proportional hazard models were used to compute hazard ratios (HRs) comparing the mortality of individuals at the 80th vs. the 20th percentile of cadmium concentrations.

RESULTS

In NHANES-III, after adjustment for sex, race/ethnicity, education, body mass index, serum cholesterol, hypertension, and NHANES phase (or cycle), the HR comparing influenza or pneumonia mortality among participants with creatinine-corrected urinary cadmium in the 80th vs. 20th percentile was 1.15 (95% CI: 1.05, 1.26; p = 0.002 ) in the population as a whole and 1.27 (95% CI: 1.12, 1.43; p = 0.002 ) among never smokers. In NHANES 1999-2006, adjusted HRs for the 80th vs. 20th percentile of blood cadmium were 1.14 (95% CI: 0.96, 1.36; p = 0.15 ) for the overall population and 1.71 (95% CI: 0.95, 3.09; p = 0.07 ) in never smokers.

DISCUSSION

Among middle-aged and older adults in the United States, higher cadmium burdens are associated with higher mortality from influenza or pneumonia. This raises the possibility that cadmium may worsen outcomes from COVID-19 infections. https://doi.org/10.1289/EHP7598.

Prenatal Exposure to Per- and Polyfluoroalkyl Substances, Umbilical Cord Blood DNA Methylation, and Cardio-Metabolic Indicators in Newborns: The Healthy Start Study

BACKGROUND

Per- and polyfluoroalkyl substances (PFAS) are environmentally persistent chemicals widely detected in women of reproductive age. Prenatal PFAS exposure is associated with adverse health outcomes in children. We hypothesized that DNA methylation changes may result from prenatal PFAS exposure and may be linked to offspring cardio-metabolic phenotype.

OBJECTIVES

We estimated associations of prenatal PFAS with DNA methylation in umbilical cord blood. We evaluated associations of methylation at selected sites with neonatal cardio-metabolic indicators.

METHODS

Among 583 mother-infant pairs in a prospective cohort, five PFAS were quantified in maternal serum (median 27 wk of gestation). Umbilical cord blood DNA methylation was evaluated using the Illumina HumanMethylation450 array. Differentially methylated positions (DMPs) were evaluated at a false discovery rate ( FDR ) < 0.05 and differentially methylated regions (DMRs) were identified using comb-p (Šidák-adjusted p < 0.05 ). We estimated associations between methylation at candidate DMPs and DMR sites and the following outcomes: newborn weight, adiposity, and cord blood glucose, insulin, lipids, and leptin.

RESULTS

Maternal serum PFAS concentrations were below the median for females in the U.S. general population. Moderate to high pairwise correlations were observed between PFAS concentrations (ρ = 0.28 - 0.76 ). Methylation at one DMP (cg18587484), annotated to the gene TJAP1, was associated with perfluorooctanoate (PFOA) at FDR <   0.05 . Comb-p detected between 4 and 15 DMRs for each PFAS. Associated genes, some common across multiple PFAS, were implicated in growth (RPTOR), lipid homeostasis (PON1, PON3, CIDEB, NR1H2), inflammation and immune activity (RASL11B, RNF39), among other functions. There was suggestive evidence that two PFAS-associated loci (cg09093485, cg09637273) were associated with cord blood triglycerides and birth weight, respectively (FDR <   0.1 ).

DISCUSSION

DNA methylation in umbilical cord blood was associated with maternal serum PFAS concentrations during pregnancy, suggesting potential associations with offspring growth, metabolism, and immune function. Future research should explore whether DNA methylation changes mediate associations between prenatal PFAS exposures and child health outcomes. https://doi.org/10.1289/EHP6888.

Prenatal exposure to perfluoroalkyl substances and thyroid hormone concentrations in cord plasma in a Chinese birth cohort

BACKGROUND

Evidence of associations between prenatal exposure to perfluoroalkyl substances (PFASs) and fetal thyroid hormones (THs) is controversial, and few studies have estimated the associations, while addressing the high correlations among multiple PFASs. We aimed to examine the associations between prenatal PFAS exposure and thyroid hormone concentrations in cord blood.

METHODS

A total of 300 mother-infant pairs from the Shanghai-Minhang Birth Cohort Study were included. We measured the concentrations of eight PFASs in maternal plasma samples collected at 12-16 gestational weeks, as well as those of total thyroxine (T4), free T4 (FT4), total triiodothyronine (T3), free T3 (FT3), and thyroid stimulating hormone (TSH) in cord plasma. We estimated the associations between maternal PFAS concentrations and TH concentrations using linear regression and Bayesian kernel machine regression (BKMR) models.

RESULTS

In BKMR models, higher PFAS mixture concentrations were associated with increased T3 concentrations, and there were suggestive associations with increased FT3 concentrations. For single-exposure effects in BKMR models, a change in PFDA, PFUdA, and PFOA concentrations from the 25th to 75th percentile was associated with a 0.04 (95%CrI: - 0.01, 0.09), 0.02 (95%CrI: - 0.03, 0.07), and 0.03 (95%CrI: - 0.001, 0.06) nmol/L increase in T3 concentrations, respectively. PFOA, PFNA, and PFDA were the predominant compounds in PFASs-FT3 associations, and the corresponding estimates were 0.11 (95% CrI: 0.02, 0.19), - 0.17 (95% CrI: - 0.28, - 0.07), and 0.12 (95% CrI: - 0.004, 0.24) pmol/L, respectively. A change in PFNA and PFOA concentrations from the 25th to 75th percentile was associated with a - 1.69 (95% CrI: - 2.98, - 0.41) μIU/mL decrease and a 1.51 (95% CrI: 0.48, 2.55) μIU/mL increase in TSH concentrations. The associations of PFOA and PFNA with T3/FT3 were more pronounced in boys, while those with TSH were more pronounced in girls.

CONCLUSION

Our results suggest that prenatal exposure to multiple PFASs was associated with thyroid hormones in cord blood. However, individual PFAS had varied effects-differing in magnitude and direction-on fetal thyroid hormones.