Exposure to phthalates and breast cancer risk in northern Mexico

Exposure to di-2-ethylhexyl phthalate and breast neoplasm incidence: A cohort study

BACKGROUND

Phthalates are ubiquitous environmental endocrine disruptors. As the predominant phthalate, di-2-ethylhexyl phthalate (DEHP) has been considered possibly carcinogenic to humans but large-scale longitudinal evidence is needed to further clarify its carcinogenicity.

OBJECTIVES

To examine the association between DEHP exposure and incidence of breast malignant neoplasm, carcinoma in situ and benign neoplasm.

METHODS

A total of 273,295 women from UK Biobank cohort were followed up for a median of 13.5 years. Disease information was collected from National Health Service Cancer Registry and National Death Index. Baseline and yearly-average level of DEHP exposure were estimated for each individual by linking chemical monitoring record of European Environment Agency with home address of the participants by Kriging interpolation model. Cox proportional hazard model was employed to estimate the association between DEHP exposure and breast neoplasms.

RESULTS

The median (IQR) of baseline and yearly-average DEHP concentration were 8000.25 (interquartile range: 6657.85-11,948.83) and 8000.25 (interquartile range: 1819.93-11,359.55) μg/L. The highest quartile of baseline DEHP was associated with 1.11 fold risk of carcinoma in situ (95 % CI, 1.00, 1.23, p < 0.001) and 1.27 fold risk of benign neoplasm (95 % CI, 1.05, 1.54, p < 0.001). As for yearly-average exposure, each quartile of DEHP was positively associated with higher risk of malignant neoplasm (HR, 1.05; 95 % CI, 1.03, 1.07, p < 0.001), carcinoma in situ (HR, 1.08; 95 % CI, 1.04, 1.11, p < 0.001) and benign neoplasm (HR, 1.13; 95 % CI, 1.07, 1.20, p < 0.001). Stratification analysis showed no significant modification effects on the DEHP-neoplasm relationship by menopausal status or ethnicity but a suggestive higher risk in younger women and those who underwent oral contraceptive pill therapy. In sensitivity analysis, the associations remained when excluding the cases diagnosed within 2 years post baseline.

CONCLUSIONS

Real-world level of DEHP exposure was associated with higher risk of breast neoplasms. Because of the health risks associated with DEHP, its release to the environment should be managed.

Association between urinary phthalates and phthalate metabolites and cancer risk: A systematic review and meta-analysis

Phthalates, widely utilized in industrial products, are classified as endocrine-disrupting chemicals (EDCs). Although certain phthalate and their metabolites have been implicated in cancer development, the reported findings have exhibited inconsistencies. Therefore, we conducted the comprehensive literature search to assess the association between phthalate and their metabolites and cancer risk by identifying original studies measuring phthalates or their metabolites and reporting their correlation with cancer until July 4, 2023. The Odds Ratios (ORs) and corresponding 95% confidence intervals (CIs) were extracted and analyzed to estimate the risk. Pooled data from eleven studies, including 3101 cancer patients and 6858 controls, were analyzed using a fixed- or random-effects model based on heterogeneity tests. When comparing extreme categories of different phthalates and their metabolites, we observed a significant association between urinary phthalates and phthalate metabolites (MEHHP, MECPP, DBP and MBzP) and cancer risk. The findings of our meta-analysis reinforce the existing evidence that urinary phthalates and phthalate metabolites is strongly associated with cancer development. Further investigations are warranted to elucidate the underlying mechanisms of this association. These results may offer novel insights into cancer development.

Personal Care Product Use during Puberty and Incident Breast Cancer among Black, Hispanic/Latina, and White Women in a Prospective US-Wide Cohort

BACKGROUND

Some personal care products (PCPs) contain endocrine-disrupting chemicals that may affect breast cancer (BC) risk. Patterns of use vary by race and ethnicity. Use often starts in adolescence, when rapidly developing breast tissue may be more susceptible to environmental carcinogens. Few studies have examined associations of BC with PCP use during this susceptible window.

OBJECTIVES

We characterized race and ethnicity-specific patterns of PCP use at 10-13 years of age and estimated associations of use with incident BC.

METHODS

At enrollment (2003-2009), Sister Study participants (n = 4,049 Black, 2,104 Latina, and 39,312 White women) 35-74 years of age reported use of 37 "everyday" PCPs during the ages of 10-13 y (did not use, sometimes, or frequently used). We conducted race and ethnicity-specific latent class analyses to separately identify groups of women with similar patterns of beauty, hair, and skincare/hygiene product use. We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for associations of identified PCP classes and single products with incident BC using Cox proportional hazards regression.

RESULTS

During a mean follow-up time of 10.8 y, 280 Black, 128 Latina, and 3,137 White women were diagnosed with BC. Classes of adolescent PCP use were not clearly associated with BC diagnosis among Black, Latina, or White women. HRs were elevated but imprecise for frequent nail product and perfume use in Black women (HR = 1.34; 95% CI: 0.85, 2.12) and greater hair product use in Black (HR = 1.28; 95% CI: 0.91, 1.80) and Latina (HR = 1.42; 95% CI: 0.81, 2.48) women compared with lighter use. In single-product models, we observed higher BC incidence associated with frequent use of lipstick, nail products, pomade, perfume, makeup remover, and acne/blemish products in at least one group.

DISCUSSION

This work provides some support for the hypothesis that PCP use during puberty is associated with BC risk. More research is needed to confirm these novel findings. https://doi.org/10.1289/EHP13882.

Trends and Age-Period-Cohort Effect on Incidence of Male Breast Cancer from 1980 to 2019 in Taiwan and the USA

Although male breast cancer (MBC) is globally rare, its incidence significantly increased from 1990 to 2017. The aim of this study was to examine variations in the trends of MBC incidence between populations in Taiwan and the USA from 1980 to 2019. The Taiwan Cancer Registry database and the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute of the USA were used. The age-standardized incidence rate was calculated using the world standard population in 2000. The long-term trends of the age, time period, and birth cohort effect on MBC incidence rates were estimated using the SEER Age-Period-Cohort Web Tool. The results revealed that the incidence of MBC in both countries increased from 2010 to 2019 (Taiwan: average annual percentage change (AAPC) = 2.59%; USA: AAPC = 0.64%). The age and period effects on the incidence rates in both countries strengthened, but the cohort effect was only identified in Taiwan (Rate ratio: 4.03). The identified cohort effect in this study bears resemblance to that noted in a previous investigation on female breast cancer in Taiwan. This suggests the possible presence of common environmental factors influencing breast cancer incidence in both genders, such as a high fat diet and xenoestrogen.

Occurrence, ecological and health risk assessment of phthalates in a polluted urban river used for agricultural land irrigation in central Mexico

The escalating global concern on phthalate esters (PAEs) stems from their status as emerging contaminants, marked by their toxicity and their potential to harm both the environment and human health. Consequently, this study aimed to evaluate the occurrence, spatial distribution, and ecological and health risks associated with PAEs in the Atoyac River, an urban waterway in central Mexico that receives untreated and poorly treated urban and industrial wastewater. Of the 14 PAEs analyzed in surface water samples collected along the river mainstream, nine were detected and quantified by GC-MS. The concentration of each detected PAE ranged from non-detected values to 25.7 μg L-1. Di (2-ethylhexyl) phthalate (DEHP) and di-n-hexyl phthalate (DnHP) were detected in all sampling sites, with concentrations ranging from 8.1 to 19.4 μg L-1 and from 6.3 to 15.6 μg L-1, respectively. The cumulative Σ9PAEs concentrations reached up to 81.1 μg L-1 and 96.0 μg L-1 in sites downstream to high-tech industrial parks, pinpointing industrial wastewater as the primary source of PAEs. Given that the river water is stored in a reservoir and used for cropland irrigation, this study also assessed the ecological and human health risks posed by PAEs. The findings disclosed a high ecological risk to aquatic organisms exposed to di-n-octyl phthalate (DOP), dicyclohexyl phthalate (DCHP), benzyl butyl phthalate (BBP), DEHP, and DnHP. Additionally, a high carcinogenic (CR > 10-4) and noncarcinogenic (HQ > 10) risk for the DEHP exposure through ingestion of crops irrigated with river water was identified for both children and adults. These data on PAEs provide valuable insights for the Mexican government's future strategies in regulating these pollutants in water bodies, thereby minimizing the environmental and human health risks that they pose.

Use of personal care product mixtures and incident hormone-sensitive cancers in the Sister Study: A U.S.-wide prospective cohort

BACKGROUND

Personal care products (PCPs), a source of endocrine-disrupting chemical exposure, may be associated with the risk of hormone-sensitive cancers. Few studies have investigated associations for PCP use with the incidence of hormone-sensitive cancers or considered the joint effect of multiple correlated PCPs. We examined associations between frequently used, or "everyday", PCPs and incident cancers of the breast, ovary, and uterus with a fucus on the joint effect of multiple product exposure.

METHODS

Sister Study participants (n=49 899) self-reported frequency of use in the year before enrollment (2003-2009) for 41 PCPs. Using five-level frequency categories based on questionnaire options, hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated for the associations between multiple PCP use and incident breast, ovarian, and uterine cancer using quantile-based g-computation with Cox proportional hazards regression as the underlying model. Multiple PCP use was examined using groupings (beauty, hygiene, and skincare products) determined by both a priori knowledge and Spearman correlation coefficients for co-occurring product use. Associations between individual PCPs and the three cancers were also examined using Cox proportional hazards models coupling with Benjamini-Hochberg procedure for multiple comparisons.

RESULTS

Over an average of 11.6 years, 4 226 breast, 277 ovarian, and 403 uterine cancer cases were identified. Positive associations were observed between the hygiene mixture and ovarian cancer (HR=1.35, 95%CI=1.00, 1.83) and the beauty mixture with postmenopausal breast cancer (HR=1.08, 95%CI=1.01, 1.16). Additionally, we observed an inverse association between the skincare mixture and breast cancer (HR=0.91, 95%CI=0.83, 0.99). No significant associations were observed for individual products after corrected for multiple comparison.

CONCLUSIONS

Findings from this multi-product, joint-effect approach contribute to the growing body of evidence for associations between PCPs and breast cancer and provides novel information on ovarian and uterine cancer.

Evidence-based identification of breast cancer and associated ovarian and uterus cancer risk components in source waters from high incidence area in the Pearl River Basin, China

Breast cancer, ovarian cancer, and uterus cancer are among the most common female cancers. They are suspected to associate with exposures to specific environmental pollutants, which remain unidentified in source waters. In this work, we focused on the Pearl River Basin region in China, which experienced a high incidence of breast, ovarian, and uterus cancers. Combining cancer patient data, mammalian cell cytotoxicity analyses, and exhaustive historical and current chemical assessments, we for the first time identified source water components that promoted proliferation of mammalian cells, and confirmed their association with these female cancers via the estrogen receptor mediated pathway. Therefore, the components that have previously been found to enhance the proliferation of estrogen receptor-containing cells through endocrine disruption could be the crucial factor. Based on this, components that matched with this toxicological characteristic (i.e., estrogen-like effect) were further identified in source waters, including (1) organic components: phthalates, bisphenol A, nonylphenols, and per-/polyfluoroalkyls; (2) inorganic components: Sb, Co, As, and nitrate. Moreover, these identified water components were present at levels comparable to other regions with high female cancer prevalence, suggesting that the potential risk of these components may not be exclusive to the study region. Together, multiple levels of evidence suggested that long-term co-exposures to source water estrogenic components may be important to the development of breast, ovarian, and uterus cancers.

Accumulation, sources, and health risks of phthalic acid esters (PAEs) in road dust from heavily industrialized, urban and rural areas in southern Iran

In this research, a total of 51 road dust samples were collected from three districts (Asaluyeh, Bushehr, and Goshoui) in the south of Iran from April to June 2022 and analyzed for the concentration of 7 phthalic acid esters (PAEs) compounds. Asaluyeh was considered as an industrial area (near gas and petrochemical industries), Bushehr as an urban area, and Goshoui as a rural area (far from pollution sources). The PAEs concentration of the street dust samples was determined using a mass detection gas chromatography (GC/MS). The mean ± SD levels of ƩPAEs in samples from industrial, urban, and rural sources were 56.9 ± 11.5, 18.3 ± 9.64, and 5.68 ± 1.85 μg/g, respectively. The mean concentration levels of ƩPAEs was significantly (P < 0.05) higher in samples from the industrial area than urban and rural areas. The mean levels of di(2-Ethylhexyl) phthalate (DEHP) in industrial, urban, and rural areas were 20.3 ± 8.76, 4.59 ± 1.71, and 2.35 ± 0.98 μg/g, respectively. The results of the PCA analysis indicate that the likely major sources of PAEs in the road dust in the studied areas are the application of various plasticizers in industry, solvents, chemical fertilizers, waste disposal, wastewater (e.g., agricultural, domestic, and industrial), and the use of plastic films and plastic-based irrigation pipes in greenhouses. As well as, it was found that the non-cancer risk of exposure to dust-bound PAEs was higher for children than for adults. These values were <1 for both age groups (children and adults) and the exposure of inhabitants to PAEs in road dust did not pose a notable non-cancer risk. The cancer risk from exposure to DEHP in road dust was below the standard range of 10-6 in all three areas. Further studies that consider different routes of exposure to these contaminants are needed for an accurate risk assessment. Moreover, since higher PAEs level was found in industrial area, decision-makers should adopt strict strategies to control the discharging of pollution from industries to the environment and human societies.

A review on solution- and vapor-responsive sensors for the detection of phthalates

Phthalic acid esters, largely referred to as phthalates, are today acknowledged as important pollutants used in the manufacture of polyvinyl chloride (PVC)-based plastics, whose use extends to almost every aspect of modern life. The risk of exposure to phthalates is particularly relevant as high concentrations are regularly found in drinking water, food-contact materials and medical devices, motivating an immense body of research devoted to methods for their detection in liquid samples. Conversely, phthalate vapors have only recently been acknowledged as potentially important atmospheric pollutants and as early fire indicators; additionally, deposition of these vapors can pose significant problems to the proper functioning of spacecraft and diverse on-board devices, leading to major space agencies recognizing the need of developing vapor-responsive phthalate sensors. In this manuscript we present a literature survey on solution- and vapor-responsive sensors and analytical assays for the detection of phthalates, providing a detailed analysis of a vast array of analytical data to offer a clear idea on the analytical performance (limits of detection and quantification, linear range) and advantages provided by each class of sensor covered in this review (electrochemical, optical and vapor-responsive) in the context of their potential real-life applications; the manuscript also gives detailed fundamental information on the various physicochemical responses exploited by these sensors and assays that could potentially be harnessed by new researchers entering the field.

Seasonal distribution characteristics and ecological risk assessment of phthalate esters in surface sediment of Songhua River basin

Phthalic acid esters (PAEs) are typical industrial chemicals used in China. PAEs have received considerable attention because of their ubiquity and potential hazard to humans and the ecology. The spatiotemporal distributions of six PAEs in the surface sediments of the Songhua River in the spring (March), summer (July), and autumn (September) are investigated in this study. The total concentration of phthalic acid esters (∑6PAEs) ranges from 1.62 × 102 ng g-1 dry weight (dw) to 3.63 × 104 ng g-1·dw, where the amount in the spring is substantially higher (p < 0.01) than those in the autumn and summer. Seasonal variations in PAEs may be due to rainfall and temperature. The ∑6PAEs in the Songhua River's upper reaches are significantly higher than those in the middle and lower reaches (p < 0.05). Dibutyl phthalate (DBP) and di(2-ethylhexyl) phthalate (DEHP) are the two most abundant PAEs. The ecological hazard of five PAEs is assessed using the hazard quotient method. DBP and DEHP pose moderate or high ecological risks to aquatic organisms at various trophic levels. PAEs originate primarily from industrial, agricultural, and domestic sources. Absolute principal components-multiple linear regression results indicate that agricultural sources are the most dominant contributor to the ∑6PAEs (53.7%). Guidelines for controlling PAEs pollution in the Songhua River are proposed.

The no-observed-adverse-effect level of phthalates promotes proliferation and cell cycle progression in normal human breast cells

OBJECTIVE

The data on the association between phthalates and breast cancer risk remains inconsistent. This study aimed to explore the possible mechanism of low-dose exposures of phthalates, including Butyl benzyl phthalate (BBP), di(n-butyl) phthalate (DBP), and di(20ethylhexyl) phthalate (DEHP), on breast tumorigenesis.

METHODS AND METHODS

MCF-10A normal breast cells were treated with phthalates (10 and 100 nM) and 17β-estradiol (E2, 10 nM), which were co-cultured with fibroblasts from normal mammary tissue. Cell viability, cycle, and apoptosis were detected by MTT assay, flow cytometry, and TUNEL assay respectively. The expression levels of related proteins were determined by Western blot.

RESULTS

Like E2, both 10 nM and 100 nM phthalates exerted significantly higher cell viability, lower apoptosis, and increased cell numbers in the S and G2/M phases with up-regulation of cyclin D/CDK4, cyclin E/CDK2, cyclin A/CDK2, cyclin A/CDK1, and cyclin B/CDK1, compared with the control group. Significant increase in PDK1, P13K, p-AKT, p-mTOR, and BCL-2 expression and a decrease in Bax protein, cytochrome C, caspase 8, and caspase 3 levels were noted in cells treated with 10 nM and 100 nM phthalates and E2, compared with the control group and MCF-10A cells co-cultured with fibroblasts. The effects of the three phthalates were noted to be dose-dependent.

CONCLUSIONS

The results indicate that phthalates at a level below its no-observed-adverse-effect concentration, as defined by the current standards, still induce cell cycle progression and proliferation as well as inhibit apoptosis of normal breast cells. Thus, the possibility of breast tumorigenesis through chronic phthalate exposure should be considered.

Worldwide risk assessment of phthalates and bisphenol A in humans: The need for updating guidelines

Phthalates and bisphenol A (BPA) are compounds widely used as raw materials in the production of plastics, making them ubiquitous in our daily lives. This results in widespread human exposure and human health hazards. Although efforts have been conducted to evaluate the risk of these compounds in diverse regions around the world, data scattering may mask important trends that could be useful for updating current guidelines and regulations. This study offers a comprehensive global assessment of human exposure levels to these chemicals, considering dietary and nondietary ingestion, and evaluates the associated risk. Overall, the exposure daily intake (EDI) values of phthalates and BPA reported worldwide ranged from 1.11 × 10-7 to 3 700 µg kg bw-1 d-1 and from 3.00 × 10-5 to 6.56 µg kg bw-1 d-1, respectively. Nevertheless, the dose-additive effect of phthalates has been shown to increase the EDI up to 5 100 µg kg bw-1 d-1, representing a high risk in terms of noncarcinogenic (HQ) and carcinogenic (CR) effects. The worldwide HQ values of phthalates and BPA ranged from 2.25 × 10-7 to 3.66 and from 2.74 × 10-7 to 9.72 × 10-2, respectively. Meanwhile, a significant number of studies exhibit high CR values for benzyl butyl phthalate (BBP) and di(2-ethylhexyl) phthalate (DEHP). Moreover, DEHP has shown the highest maximum mean CR values for humans in numerous studies, up to 179-fold higher than BBP. Despite mounting evidence of the harmful effects of these chemicals at low-dose exposure on animals and humans, most regulations have not been updated. Thus, this article emphasizes the need for updating guidelines and public policies considering compelling evidence for the adverse effects of low-dose exposure, and it cautions against the use of alternative plasticizers as substitutes for phthalates and BPA because of the significant gaps in their safety.

The G Protein-Coupled Estrogen Receptor (GPER): A Critical Therapeutic Target for Cancer

Estrogens have been implicated in the pathogenesis of various cancers, with increasing concern regarding the overall rising incidence of disease and exposure to environmental estrogens. Estrogens, both endogenous and environmental, manifest their actions through intracellular and plasma membrane receptors, named ERα, ERβ, and GPER. Collectively, they act to promote a broad transcriptional response that is mediated through multiple regulatory enhancers, including estrogen response elements (EREs), serum response elements (SREs), and cyclic AMP response elements (CREs). Yet, the design and rational assignment of antiestrogen therapy for breast cancer has strictly relied upon an endogenous estrogen-ER binary rubric that does not account for environmental estrogens or GPER. New endocrine therapies have focused on the development of drugs that degrade ER via ER complex destabilization or direct enzymatic ubiquitination. However, these new approaches do not broadly treat all cancer-involved receptors, including GPER. The latter is concerning since GPER is directly associated with tumor size, distant metastases, cancer stem cell activity, and endocrine resistance, indicating the importance of targeting this receptor to achieve a more complete therapeutic response. This review focuses on the critical importance and value of GPER-targeted therapeutics as part of a more holistic approach to the treatment of estrogen-driven malignancies.

Research Recommendations for Selected IARC-Classified Agents: Impact and Lessons Learned

BACKGROUND

The International Agency for Research on Cancer (IARC) Monographs program assembles expert working groups who publish a critical review and evaluation of data on agents of interest. These comprehensive reviews provide a unique opportunity to identify research needs to address classification uncertainties. A multidisciplinary expert review and workshop held in 2009 identified research gaps and needs for 20 priority occupational chemicals, metals, dusts, and physical agents, with the goal of stimulating advances in epidemiological studies of cancer and carcinogen mechanisms. Overarching issues were also described.

OBJECTIVES

In this commentary we review the current status of the evidence for the 20 priority agents identified in 2009. We examine whether identified Research Recommendations for each agent were addressed and their potential impact on resolving classification uncertainties.

METHODS

We reviewed the IARC classifications of each of the 20 priority agents and identified major new epidemiological and human mechanistic studies published since the last evaluation. Information sources were either the published Monograph for agents that have been reevaluated or, for agents not yet reevaluated, Advisory Group reports and literature searches. Findings are described in view of recent methodological developments in Monographs evidence evaluation processes.

DISCUSSION

The majority of the 20 priority agents were reevaluated by IARC since 2009. The overall carcinogen classifications of 9 agents advanced, and new cancer sites with either "sufficient" or "limited" evidence of carcinogenicity were also identified for 9 agents. Examination of published findings revealed whether evidence gaps and Research Recommendations have been addressed and highlighted remaining uncertainties. During the past decade, new research addressed a range of the 2009 recommendations and supported updated classifications for priority agents. This supports future efforts to systematically apply findings of Monograph reviews to identify research gaps and priorities relevant to evaluation criteria established in the updated IARC Monograph Preamble. https://doi.org/10.1289/EHP12547.

Latin America and the Caribbean Code Against cancer 1st edition: Environment, occupation, and cancer

Within the framework of the Latin America and Caribbean region (LAC) Code Against Cancer 1st edition, the current work presents recommendations to reduce exposure to environmental and occupational carcinogenic agents relevant for LAC. Using the methodology established by the International Agency for Research on Cancer (IARC) in the World Code Against Cancer Framework and experience from developing the European Code Against Cancer 4th edition, a working group of LAC cancer-prevention experts reviewed the list of Group I IARC carcinogenic agents, identified prevalent environmental and occupational exposures in the region, and proposed evidence-based cancer prevention recommendations suited to the epidemiological, socioeconomic, and cultural conditions of LAC countries. Two sets of recommendations were drafted: those targeting the general public and a second set for policymakers. Outdoor and indoor air pollution, ultra-violet radiation and occupational exposures to silica dust, asbestos, benzene, diesel, and welding fumes were identified as prevalent carcinogens in LAC and as agents that could be reduced or eliminated to prevent cancers. Recommendations for additional risk factors were not included due to insufficient data of their attributable burden in LAC (sunbeds, radon, aflatoxin), or lack of a clear preventive action to be taken by the individual (arsenic in drinking water, medical radiation), or lack of evidence of carcinogenicity effect (bisphenol A, phthalates, and pesticides). A broad consensus was reached on environmental and occupational carcinogenic exposures present throughout the LAC region and on individual-level and public policy-level recommendations to reduce or eliminate these exposures. Key educational content for the dissemination of these recommendations was also developed as part of LAC Code Against Cancer 1st Edition.

Insight into suppression of dibutyl phthalate on DOM removal during municipal sewage treatment using fluorescence spectroscopy with PARAFAC and moving-window 2D-COS

Dibutyl phthalate (DBP) has been widely detected in municipal and industrial wastewater, which could indirectly inhibit pollutant removals, especially degradation of dissolved organic matter (DOM). Here, the inhibition of DBP on DOM removal from wastewater in pilot-scale A2O-MBR system was investigated by fluorescence spectroscopy with two-dimensional correlation (2D-COS) and structural equation modeling (SEM). Seven components were extracted from DOM using parallel factor analysis, i.e., tryptophan-like (C1 and C2), fulvic-like (C4), tyrosine-like (C5), microbial humic-like (C6) and heme-like (C7). The tryptophan-like had a blue-shift at DBP occurrence, defined as blue-shift tryptophan-like (C3). DBP with 8 mg L^-1 exhibited a stronger inhibition on removals of DOM fractions, extraordinarily tyrosine-like and tryptophan-like in anoxic unit than DBP of 6 mg L^-1 by moving-window 2D-COS. The indirect removals of C1 and C2 through the C3 removal were more strongly inhibited by 8 mg L^-1 DBP than those by 6 mg L^-1 DBP, while the former exhibited a weaker inhibition on the direct degradation of C1 and C2 than the latter via SEM. Based on metabolic pathways, abundances of key enzymes secreted by microorganism in anoxic unit, degrading tyrosine-like and tryptophan-like, were higher in wastewater with 6 mg L^-1 DBP than those with 8 mg L^-1 DBP. These could provide a potential approach for online monitoring of DBP concentrations in wastewater treatment plants, which could rectify operating parameters, and then enhance the treatment efficiencies.

Long-term DEHP/MEHP exposure promotes colorectal cancer stemness associated with glycosylation alterations

Plasticizers are considered as environmental pollution released from medical devices and increased potential oncogenic risks in clinical therapy. Our previous studies have shown that long-term exposure to di-ethylhexyl phthalate (DEHP)/mono-ethylhexyl phthalate (MEHP) promotes chemotherapeutic drug resistance in colorectal cancer. In this study, we investigated the alteration of glycosylation in colorectal cancer following long-term plasticizers exposure. First, we determined the profiles of cell surface N-glycomes by using mass spectrometry and found out the alterations of α2,8-linkages glycans. Next, we analyzed the correlation between serum DEHP/MEHP levels and ST8SIA6 expression from matched tissues in total 110 colorectal cancer patients. Moreover, clinical specimens and TCGA database were used to analyze the expression of ST8SIA6 in advanced stage of cancer. Finally, we showed that ST8SIA6 regulated stemness in vitro and in vivo. Our results revealed long-term DEHP/MEHP exposure significantly caused cancer patients with poorer survival outcome and attenuated the expression of ST8SIA6 in cancer cells and tissue samples. As expected, silencing of ST8SIA6 promoted cancer stemness and tumorigenicity by upregulating stemness-associated proteins. In addition, the cell viability assay showed enhanced drug resistance in ST8SIA6 silencing cells treated with irinotecan. Besides, ST8SIA6 was downregulated in the advanced stage and positively correlated with tumor recurrence in colorectal cancer. Our results imply that ST8SIA6 potentially plays an important role in oncogenic effects with long-term phthalates exposure.

Regulation of the cell cycle and P13K/AKT/mTOR signaling pathway by phthalates in normal human breast cells

OBJECTIVE

To investigate the impact of phthalates, including Butyl benzyl phthalate (BBP), di(n-butyl) phthalate (DBP), and di(2-ethylhexyl) phthalate (DEHP), in breast carcinogenesis.

MATERIALS AND METHODS

MCF-10A normal breast cells were treated with phthalates (100 nM) and 17β-estradiol (E2, 10 nM), which were co-cultured with fibroblasts from normal mammary tissue adjacent to estrogen receptor positive primary breast cancers. Cell viability was determined using a 3-(4,5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Cell cycles were analyzed using flow cytometry. The proteins involving cell cycles and P13K/AKT/mTOR signaling pathway were then evaluated by Western blot analysis.

RESULTS

MCF-10A co-cultured cells treated with E2, BBP, DBP, and DEHP exhibited a significant increase in cell viability using MTT assay. The expressions of P13K, p-AKT, and p-mTOR, as well as PDK1 expression, were significantly higher in MCF-10A cells treated with E2 and phthalates. E2, BBP, DBP, and DEHP significantly increased cell percentages in the S and G2/M phases. The significantly higher expression of cyclin D/CDK4, cyclin E/CDK2, cyclin A/CDK2, cyclin A/CDK1, and cyclin B/CDK1 in MCF-10A co-cultured cells were induced by E2 and these three phthalates.

CONCLUSION

These results provide consistent data regarding the potential role of phthalates exposure in the stimulating proliferation of normal breast cells, enhancing cell viability, and driving P13K/AKT/mTOR signaling pathway and cell cycle progression. These findings strongly support the hypothesis that phthalates may play a crucial role in breast tumorigenesis.

The Cell Transformation Assay: A Historical Assessment of Current Knowledge of Applications in an Integrated Approach to Testing and Assessment for Non-Genotoxic Carcinogens

The history of the development of the cell transformation assays (CTAs) is described, providing an overview of in vitro cell transformation from its origin to the new transcriptomic-based CTAs. Application of this knowledge is utilized to address how the different types of CTAs, variously addressing initiation and promotion, can be included on a mechanistic basis within the integrated approach to testing and assessment (IATA) for non-genotoxic carcinogens. Building upon assay assessments targeting the key events in the IATA, we identify how the different CTA models can appropriately fit, following preceding steps in the IATA. The preceding steps are the prescreening transcriptomic approaches, and assessment within the earlier key events of inflammation, immune disruption, mitotic signaling and cell injury. The CTA models address the later key events of (sustained) proliferation and change in morphology leading to tumor formation. The complementary key biomarkers with respect to the precursor key events and respective CTAs are mapped, providing a structured mechanistic approach to represent the complexity of the (non-genotoxic) carcinogenesis process, and specifically their capacity to identify non-genotoxic carcinogenic chemicals in a human relevant IATA.

Quantitative analysis of phthalates using a pyrolyzer gas chromatography/mass spectrometry method

A pyrolyzer gas chromatography/mass spectrometry (GC/MS) method eliminates toxic solvents that burden our environment and can address the crucial problem of the solvent extraction GC/MS method. The purpose of this study is to establish an efficient quantitative analysis method for 10 phthalates that are regulated by the several governments. A change of concentrations over time for phthalates and internal standards was measured to verify the feasibility of using an auto sampler that facilitates analyzing multiple samples. Both standards maintained constant concentrations over the appropriate time for analysis. A certified reference material under the auspices of the Korea Research Institute of Standards and Science was used to verify the calibration curve obtained by the pyrolyzer GC/MS method, and a deviation was considered similar to the solvent extraction GC/MS method. Then, the limit of detection and limit of quantitation values were confirmed for various consumer products. To verify the reliability of the method, a comparative test with several accredited testing institutes was conducted, and the results were within the standard deviations of the results provided by the institutes. These results indicate that the pyrolyzer GC/MS method can be used in not only screening but also in accurate quantitative analysis.

Low-dose phthalates promote breast cancer stem cell properties via the oncogene ΔNp63α and the Sonic hedgehog pathway

BACKGROUND

The omnipresence of human phthalate (PAE) exposure is linked to various adverse health issues, including breast cancer. However, the effects of low-dose PAE exposure on breast cancer stem cells (BCSCs) and the underlying mechanism remain unexplored.

METHODS

BCSCs from breast cancer cell lines (MDA-MB-231 and MCF-7) were enriched using a tumorsphere formation assay. Gene and protein expression was detected by measurement of quantitative real-time reverse transcription PCR, western blot, and immunofluorescence assays. Transient transfection assays were used to evaluate the involvement of Gli1, a signaling pathway molecule and ΔNp63α, an oncogene in influencing the PAE-induced characteristics of BCSCs.

RESULTS

PAE (butylbenzyl phthalate, BBP; di-butyl phthalate, DBP; di-2-ethylhexyl phthalate, DEHP) exposure of 10^-9 M significantly promoted the tumorsphere formation ability in BCSCs. Breast cancer spheroids with a 10^-9 M PAE exposure had higher levels of BCSC marker mRNA and protein expression, activated sonic hedgehog (SHH) pathway, and increased mRNA and protein levels of an oncogene, ΔNp63α. Furthermore, suppression of the SHH pathway attenuated the effects of PAEs on BCSCs. And the overexpression of ΔNp63α enhanced PAE-induced characteristics of BCSCs, while low expression of ΔNp63α inhibited the promotion effects of PAEs on BCSCs and the SHH pathway.

CONCLUSION

Low-dose PAE exposure promoted the stem cell properties of BCSCs in a ΔNp63α- and SHH-dependent manner. The influence of low-dose exposure of PAEs and its relevance for the lowest observed effect concentrations requires further investigation, and the precise underlying mechanism needs to be further explored.

The impact of endocrine disrupting compounds and carcinogens in wastewater: Implications for breast cancer

The incidence of breast cancer is often associated with geographic variation which indicates that a person's surrounding environment can be an important etiological factor in cancer development. Environmental risk factors can include exposure to sewage- or wastewater, which consist of a complex mixture of pathogens, mutagens and carcinogens. Wastewater contains primarily carbonaceous, nitrogenous and phosphorus compounds, however it can also contain trace amounts of chemical pollutants including toxic metal cations, hydrocarbons and pesticides. More importantly, the contamination of drinking water by wastewater is a potential source of exposure to mammary carcinogens and endocrine disrupting compounds. Organic solvents and other pollutants often found in wastewater have been detected in various tissues, including breast and adipose tissues. Furthermore, these pollutants such as phenolic compounds in some detergents and plastics, as well as parabens and pesticides can mimic estrogen. High estrogen levels are a well-established risk factor for estrogen-receptor (ER) positive breast cancer. Therefore, exposure to wastewater is a risk factor for the initiation, progression and metastasis of breast cancer. Carcinogens present in wastewater can promote tumourigenesis through various mechanisms, including the formation of DNA adducts, gene mutations and oxidative stress. Lastly, the presence of endocrine disrupting compounds in wastewater can have negative implications for ER-positive breast cancers, where these molecules can activate ERα to promote cell proliferation, survival and metastasis. As such, strategies should be implemented to limit exposure, such as providing funding into treatment technologies and implementation of regulations that limit the production and use of these potentially harmful chemicals.

Urinary phthalate metabolite and BPA concentrations in women with cervical cancer

Environmental pollutants are involved in the development and progression of numerous cancers, including cervical cancer (CC). One possible explanation for this is the ability of several pollutants to mimic natural hormones. This study aimed to evaluate the urinary concentrations of monoesters of phthalates and bisphenol A (BPA) in women with CC. A total of 45 women were included: 15 in the control group, 12 with CC diagnosis classified in early stages IA-IIB, and 18 in late stages III-IV. Urine samples were analyzed for BPA, mono-isobutyl phthalate (MiBP), mono-n-butyl phthalate (MBP), monobenzyl phthalate (MBzP), and mono 2-ethylhexyl phthalate (MEHP) using high-performance liquid chromatography coupled to a tandem mass detector. The detection rate of environmental pollutants was 100%, with a median concentration in the control group and early-, and late-stage groups of 10.4, 9.2, 4.3, 38.4, and 12.9 µg L^-1; 3.1, 3.1, 151.1, 54.5, and 30.4 µg L^-1 and 1.9, 92.8, 3.6, 31.0, and 9.3 µg L^-1 for BPA, MEHP, MBzP, MBP, and MiBP, respectively This study reveals high levels of phthalates, particularly MEHP, in urine samples of women with CC associated with human papillomavirus (HPV) infection. Further studies are needed to evaluate the possible role of phthalates in synergy with HPV in progression to CC.

Relationship between shellfish consumption and urinary phthalate metabolites: Korean National Environmental Health Survey (KoNEHS) cycle 3 (2015-2017)

Background

Phthalates are endocrine disrupting chemicals that are widely used in the production of items of daily life such as in polyvinylchloride plastics, insecticides, and medical devices. This study aimed to determine the association between phthalate exposure and shellfish consumption using data from the Korean National Environmental Health Survey (KoNEHS) cycle 3 (2015-2017), which is a nationally representative survey.

Methods

In this study, we analyzed the KoNEHS cycle 3 data of 3,333 (1,526 men and 1,807 women) adults aged more than 19 years. Data related to the variables of sociodemographic factors, health-related behaviors, dietary factors, seafood consumption frequency, and urinary phthalate metabolites concentrations were collected. The concentrations of urinary phthalate metabolites of all the participants were divided into quartiles to define high and low concentration groups based on the 75th percentile concentration. A χ² test was conducted to analyze the distribution of independent variables. To analyze the relationship between shellfish consumption and phthalate exposure, the odds ratios (ORs) were calculated using logistic regression analysis.

Results

Total adults with shellfish consumption frequency of over once a week showed the following adjusted ORs for high concentrations of the following metabolites compared with the group that consumed shellfish once a week or less: 1.43 (95% confidence interval [CI]: 1.01-2.06) for mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), 1.43 (95% CI: 1.01-2.03) for mono-(2-ethyl-5-carboxypentyl) phthalate (MECPP), 1.57 (95% CI: 1.10-2.24) for ∑di-2-ethylhexyl phthalate (∑DEHP), 2.01 (95% CI: 1.46-2.77) for mono-carboxyoctyl phthalate (MCOP), 1.56 (95% CI: 1.11-2.18) for mono-carboxy-isononly phthalate (MCNP), and 2.57 (95% CI: 1.85-3.56) for mono (3-carboxypropyl) phthalate (MCPP).

Conclusions

The concentrations of urinary phthalate metabolites (MEOHP, MECPP, ∑DEHP, MCOP, MCNP, and MCPP) were higher in adults with a higher frequency of shellfish consumption.

An insight into sex-specific neurotoxicity and molecular mechanisms of DEHP: A critical review

Di-2-Ethylhexyl Phthalate (DEHP) is often used as an additive in polyvinyl chloride (PVC) to give plastics flexibility, which makes DEHP widely used in food packaging, daily necessities, medical equipment, and other products. However, due to the unstable combination of DEHP and polymer, it will migrate to the environment in the materials and eventually contact the human body. It has been recorded that low-dose DEHP will increase neurotoxicity in the nervous system, and the human health effects of DEHP have been paid attention to because of the extensive exposure to DEHP and its high absorption during brain development. In this study, we review the evidence that DEHP exposure is associated with neurodevelopmental abnormalities and neurological diseases based on human epidemiological and animal behavioral studies. Besides, we also summarized the oxidative damage, apoptosis, and signal transduction disorder related to neurobehavioral abnormalities and nerve injury, and described the potential mechanisms of neurotoxicity caused by DEHP. Overall, we found exposure to DEHP during the critical developmental period will increase the risk of neurobehavioral abnormalities, depression, and autism spectrum disorders. This effect is sex-specific and will continue to adulthood and even have an intergenerational effect. However, the research results on the sex-dependence of DEHP neurotoxicity are inconsistent, and there is a lack of systematic mechanisms research as theoretical support. Future investigations need to be carried out in a large-scale population and model organisms to produce more consistent and convincing results. And we emphasize the importance of mechanism research, which can enhance the understanding of the environmental and human health risks of DEHP exposure.

Health effects associated with phthalate activity on nuclear receptors

Phthalates are endocrine disruptors, widely used as plasticizers to impart flexibility in plastics, and as solvents in personal care products. Due to their nearly ubiquitous use in consumer products, most humans are exposed to phthalates daily. There has been extensive research on the reproductive health effects associated with phthalate exposure, but less attention has been paid to other actions. This review aims to summarize the known action of phthalates on different nuclear receptors. Some phthalates bind to and activate the estrogen receptor, making them weakly estrogenic. However, other phthalates antagonize androgen receptors. Some high molecular weight phthalates antagonize thyroid receptors, affecting metabolism. Several phthalates activate and interfere with the normal function of different peroxisome proliferator-activated receptors (PPARs), receptors that have critical roles in lipid metabolism and energy homeostasis. Some phthalates activate the aryl hydrocarbon receptor, which is critical for xenobiotic metabolism. Although phthalates have a short half-life in vivo, because people are continuously exposed, studies should examine the health effects of phthalates associated with long-term exposure. There is limited research on the effects of phthalates on health outcomes aside from reproductive function, particularly concerning are childhood adiposity, behavior, and learning. There is also limited information on actions of phthalates not mediated via nuclear receptors. Humans are exposed to multiple chemicals simultaneously, and how chemical mixtures act on nuclear receptor activity needs study. Although we know a great deal about phthalates, there is still much that remains uncertain. Future studies need to further examine their other potential health effects.

Integrated bioinformatic analysis to understand the association between phthalate exposure and breast cancer progression

Phthalates have been extensively used as plasticizers while manufacturing plastic-based consumer products. Estradiol mimicking properties and association studies suggest phthalates may contribute to breast cancer (BC). We performed an in-silico analysis and functional studies to understand the association between phthalate exposure and BC progression. Search for phthalate-responsive genes using the comparative toxicogenomics database identified 20 genes as commonly altered in response to multiple phthalates exposure. Of the 20 genes, 12 were significantly differentially expressed between normal and BC samples. In BC samples, 9 out of 20 genes showed a negative correlation between promoter methylation and its expression. AHR, BAX, BCL2, CAT, ESR2, IL6, and PTGS2 expression differed significantly between metastatic and non-metastatic BC samples. Gene set enrichment analysis identified metabolism, ATP-binding cassette transporters, insulin signaling, and type II diabetes as highly enriched pathways. The diagnostic assessment based on 20 genes expression suggested a sensitivity and a specificity >0.91. The aberrantly expressed phthalate interactive gene influenced the overall survival of BC patients. Drug-gene interaction analysis identified 14 genes and 523 candidate drugs, including 19 BC treatment-approved drugs. Di(2-ethylhexyl) phthlate (DEHP) exposure increased the growth, proliferation, and migration of MCF-7 and MDA-MB-231 cells in-vitro. DEHP exposure induced morphological changes, actin cytoskeletal remodeling, increased ROS content, reduced basal level lipid peroxidation, and induced epithelial to mesenchymal transition (EMT). The present approach can help to explore the potentially damaging effects of environmental agents on cancer risk and understand the underlined pathways and molecular mechanisms.

Variability in urinary phthalates, phenols, and parabens across childhood and relation to adolescent breast composition in Chilean girls

BACKGROUND

Epidemiologic evidence suggests that environmental factors acting as endocrine disrupting chemicals (EDCs) are associated with mammographic breast density and the risk of breast cancer. Exposure to EDCs during puberty, a period of rapid breast development, may affect susceptibility to breast carcinogenesis.

METHODS

In a cohort of 366 Chilean adolescents from the Growth and Obesity Cohort Study, we evaluated the relation between urinary concentrations of 15 suspected EDC biomarkers across three pubertal time points (Tanner breast stage 1 (B1), 4 (B4), and 1-year post-menarche) and breast fibroglandular volume (FGV; percent FGV [%FGV] and absolute FGV [aFGV]) and total breast volume (tBV) at 2-years post-menarche. We used linear mixed models to test differences in creatinine-corrected EDC biomarker concentrations at B4 and 1-year post-menarche compared to B1 and calculated intraclass correlation coefficients (ICC) of EDC concentrations across time points to appraise the consistency of measurements. We fit multivariable generalized estimating equations (GEEs) to evaluate windows of susceptibility for the association between log10-transformed EDCs and log10-transformed breast outcomes. GEEs were adjusted for age, body fat percentage, total caloric intake, and maternal education.

RESULTS

Urinary EDC biomarker concentrations highly varied across pubertal time points (ICC range 0.01-0.30). For 12 EDCs, biomarker concentrations decreased over time. Triclosan measured at 1-year post-menarche was inversely associated with %FGV at 2-years post-menarche (β = -0.025, 95 % confidence interval = -0.041, -0.008). Mono(2-ethyl-5-carboxypentyl) phthalate and the sum of di(2-ethylhexyl) phthalate metabolite concentrations at B4 were positively associated with aFGV and tBV at 2-years post-menarche. No measured phenols were associated with aFGV and tBV, while no measured parabens were associated with %FGV and aFGV.

CONCLUSIONS

Our study suggests relatively high variability in EDC biomarker concentrations across the peripubertal time period. We also found evidence to suggest that there may be pubertal windows of susceptibility to select EDCs for the association with adolescent breast density.

Contribution of common plastic-related endocrine disruptors to epithelial-mesenchymal transition (EMT) and tumor progression

Many chemicals, including many endocrine disruptors (EDCs) are known to leach out from various plastic consumer products and waste, and are widespread in the environment. EDCs are a large group of contaminants that can interfere with hormonal metabolism or function. In addition, there are in the literature implications of contribution by EDCs in tumor progression, the last stage of carcinogenesis driven by cells with a metastatic phenotype. The process of epithelial cells losing their apical-basal polarity and cell-to-cell contacts, and acquiring migration and invasive properties typical of mesenchymal cells is called epithelial-mesenchymal transition (EMT). It is essential for tumor progression. In human cells, plastic-related EDCs, (phthalates, bisphenol A, and the alkylphenols: nonylphenol and octylphenol) reduce epithelial E-cadherin, and increase mesenchymal N-cadherin and extracellular matrix metalloproteinases. These changes are hallmarks of EMT. In xenograft mouse studies, EDCs increase migration of cells and metastatic growth in distant tissues. Their contribution to EMT and tumor progression, the topic of this review, is important from public health perspective, because of the ubiquitous exposure to these EDCs. In this mini-review we also discuss molecular mechanisms associated with EDC-induced EMT and tumor progression.

Composting and green technologies for remediation of phthalate (PAE)-contaminated soil: Current status and future perspectives

Phthalate esters (PAEs) are hazardous organic compounds that are widely added to plastics to enhance their flexibility, temperature, and acidic tolerance. The increase in global consumption and the corresponding environmental pollution of PAEs has caused broad public concerns. As most PAEs accumulate in soil due to their high hydrophobicity, composting is a robust remediation technology for PAE-contaminated soil (efficiency 25%-100%), where microbial activity plays an important role. This review summarized the roles of the microbial community, biodegradation pathways, and specific enzymes involved in the PAE degradation. Also, other green technologies, including biochar adsorption, bioaugmentation, and phytoremediation, for PAE degradation were also presented, compared, and discussed. Composting combined with these technologies significantly enhanced removal efficiency; yet, the properties and roles of each bacterial strain in the degradation, upscaling, and economic feasibility should be clarified in future research.

Knowledge and awareness of breast cancer and breast self-examination among college-going female students in Delhi-NCR: a cross sectional study

Purpose

Breast cancer (BC) presents a major public health challenge world-over including India. While several risk-factors, early signs and symptoms of BC are known, the knowledge and awareness of this disease remains poor among the population. The present study aimed to determine the extent of knowledge and awareness of BC, its risk factors, early signs and symptoms and breast self-examination (BSE) practice as an early detection method among Indian college-going female students.

Design/methodology/approach

The authors conducted a cross-sectional survey at a University in Delhi-NCR. Data on socio-demographic, knowledge and awareness of BC including BSE was collected using a pretested questionnaire. Chi-square test and logistic regression analysis was performed. All tests were two-sided and significance was set at p < 0.05.

Findings

A total of 866 female students participated in the study with mean age of 22.32 (±0.146) years having mean body mass index (BMI) of 21.22 (±3.52). As high as 82.1% of the participants had heard of BC but while 74.8% thought early detection is possible, 70.7% believed BC cannot be prevented. Gene mutations (60.2%) were identified as a significant risk factor, while breast pain (61.4%) was commonly recognized as a sign of BC. Only 29.8% of students ever performed BSE. Increased odds of performing BSE (OR = 3.4) was found among students who recognized gene mutations as an important BC risk factor.

Research limitations/implications

Knowledge and awareness of BC including BSE among female college students were found to be below average. It is suggested that there is an urgent need for increasing BC awareness among young girls through workshops and mobile-health interventions.

Practical implications

This study provides new information on the level of knowledge and awareness of BC risk factors, sign and symptoms and self-examination practice among young college girls. Moreover, this study advocates the need for design and implementation of a sustainable digital health model for active population BC screening, which is not being done currently.

Social implications

BC is a highly aggressive disease, which is now one of the leading causes of morbidity and mortality in India and world over. Although the knowledge of BC risk factors and its signs and symptoms have increased, the awareness of these elements among the general population at large is low and/or missing, especially in India. Furthermore, as a consequence of unorganized screening programs in the country, majority of women are presenting young with locally advanced disease. Understanding the existing level of knowledge and educating school, college and University students of the pertinent factors and screening practices such as BSE could drastically help in improving the self-screening and/or clinical examination rates. This could potentially lead to early detection and improved prognosis, thus ameliorating disease burden.

Originality/value

This study is one of the few studies conducted in India among young female college students belonging to non-medical backgrounds, delineating the level of knowledge and awareness of BC risk factors and signs and symptoms along with practice of early detection method such as BSE. The study has a considerable sample size and provides valuable evidence for a need to implement programs incorporating digital health models for accelerating awareness and screening of young girls in both rural and urban settings.

End-of-life management of single-use baby diapers: Analysis of technical, health and environment aspects

Single-use baby diapers belongs to an important group of products used in the parenting journey because of their high performance and convenience. Single-use baby diapers are normally thrown away after one-time use, resulting in a waste management problem. The goal of this paper was to better understand main environmental concerns of different types of diapers and address how to reduce them, with a special consideration of waste management strategies and user behaviour practices. Furthermore, health and environmental hazards potentially associated with materials included in diapers, or substances formed from diapers during the waste treatment stage, are also analysed (e.g., phthalates, pesticides, dioxins, pesticides). Three main types of baby diapers have been analysed: single-use baby diapers, reusable baby diapers, and biodegradable single-use diapers. Each type of diaper comes with technical characteristics and environmental concerns and challenges, which are discussed in this paper to support the development of measures for the safe(r) and sustainable design, use and end of life management of baby diapers.

Simple ultrasensitive electrochemical detection of the DBP plasticizer for the risk assessment of South Korean river waters

Rapid detection of contaminants for the purpose of sensitive and quantitative monitoring of environmental hazards is an essential first step in realizing the avoidance of human health risks. In this regard, we present a fast and simple electrochemical method of detecting di-n-butyl phthalate (DBP) from river water samples using a phthalic acid group specific aptamer modified on a gold nanoparticle (AuNP) functionalized graphene oxide nano-platelet (GO) and ionic liquid (IL) nanocomposite. Here, the IL/GO nanocomposite allows an enhanced interaction with phthalate esters, thereby increasing the sensitivity of the sensor surface. The proposed sensor showed a wide linear dynamic range from 0.14 pg mL^-1 to 0.35 ng mL^-1 and from 0.35 ng mL^-1 to 7 ng mL^-1 with a detection limit of ≤0.042 pg mL^-1, which were evaluated using standard, analytical grade DBP; the limit of quantification was determined using different concentrations of DBP in DI water in comparison with gas chromatography-mass spectroscopy (GC/MS) values. The proposed sensor was used to monitor the DBP concentrations in river water samples collected from various locations across South Korea. The quantitative data from the measurements in comparison with standard GC/MS values were then used to ascertain the human health risk posed by the daily consumption of these river waters.

Association of Serum Levels of Plasticizers Compounds, Phthalates and Bisphenols, in Patients and Survivors of Breast Cancer: A Real Connection?

Phthalates and bisphenols are ubiquitous environmental pollutants with the ability to perturb different systems. Specifically, they can alter the endocrine system, and this is why they are also known as endocrine-disrupting compounds (EDCs). Interestingly, they are related to the development and progression of breast cancer (BC), but the threshold concentrations at which they trigger that are not well established. Objectives: The aim of this study was to compare the concentration measures of parent EDCs in three groups of women (without BC, with BC, and BC survivors) from two urban populations in Mexico, to establish a possible association between EDCs and this disease. We consider the measure of the parent compounds would reflect the individual’s exposure. Methods: The levels of di-ethyl-hexyl-phthalate (DEHP), butyl-benzyl-phthalate (BBP), di-n-butyl phthalate (DBP) and di-ethyl-phthalate (DEP), bisphenol A (BPA) and bisphenol S (BPS) were determined by gas chromatograph-mass spectrometry in 102 subjects, including 37 women without any pathological disease, 46 patients with BC and 19 women survivals of BC of Mexico and Toluca City. Results: All phthalates were detected in 100% of women, two of them were significantly higher in patients with different BC subtypes in Mexico City. Differential increases were observed mainly in the serum concentration of phthalates in women with BC compared to women without disease between Mexico and Toluca City. In addition, when performing an analysis of the concentrations of phthalates by molecular type of BC, DEP and BBP were found mainly in aggressive and poorly differentiated types of BC. It should be noted that female BC survivors treated with anti-hormonal therapy showed lower levels of BBP than patients with BC. BPA and BPS were found in most samples from Mexico City. However, BPS was undetectable in women from Toluca City. Discussion: The results of our study support the hypothesis of a positive association between exposure to phthalates and BC incidence.

Urinary concentration of endocrine-disrupting phthalates and breast cancer risk in Indian women: A case-control study with a focus on mutations in phthalate-responsive genes

BACKGROUND

Phthalates are known endocrine-disrupting chemicals used indiscriminately as constituents in consumer products including food processing, and packaging, cosmetics, personal care and household items. Although, few studies have assessed the risk of breast cancer on exposure to phthalates, their association with breast cancer risk in Indian women have not yet been evaluated.

METHODS

We conducted a case-control study involving 171 participants. Urinary concentrations of six phthalate dieters; DMP (Dimethyl phthalate), DEP (Diethyl phthalate), DBP (Dibutyl phthalate), BBP (benzyl butyl phthalate), DEHP (Di-2-ethyl-hexyl phthalate), DINOP (Di-n-octyl phthalate) were estimated by GC-MS and geometric means were calculated. Univariate and multivariable logistic regression was performed to assess breast cancer risk on exposure to phthalates. Genes responsive to phthalates were identified through literature search and matched with NGS data, and gene-enrichment analysis was performed.

RESULTS

Significant associations were observed between urinary phthalate concentrations and increased risk of breast cancer for di-butyl phthalate (OR=1.5, 95% CI; 1.06, 2.11, p = 0.002) and di-2-ethyl-hexyl phthalate (>median vs ≤ median; OR=2.97, 95% CI; 1.18, 7.47, p = 0.005) in multivariable analyses. We also found several phthalate-responsive gene mutations in paired breast tumor tissues, which include PTPRD (76.19%), AR (42.86%), CYP1A1 (42.86%), CYP19A1 (23.81%), AHRR (19.05%), PIK3CA (19.05%), CYP1B1 (9.52%), RB1 (9.52%) and MMP9 (9.52%). Gene-enrichment analysis revealed that these genes form a major part of ER/PR, PPAR and HIF-1α-TGF-β signaling cascades involved in breast cancer CONCLUSION: Although the sample size is small, in this first case-control study from India, DBP and DEHP were found to be associated with increased risk of invasive breast cancer and tumor tissues revealed mutations in several phthalate-responsive genes. It is, therefore suggested that human biomonitoring in India and larger studies evaluating the early life genetic and epigenetic alterations on phthalates exposure are required to establish their role in breast carcinogenesis.

Diagnostic Fragmentation Pathways for Identification of Phthalate Metabolites in Nontargeted Analysis Studies

Phthalates have been studied due to their linkages with adverse developmental effects; however, metabolites of this class of compounds are undercharacterized and are poorly captured by traditional targeted analysis. In this study, we developed a nontargeted analysis approach for identifying and classifying phthalate metabolites based on a comprehensive study of their fragmentation pathways in electrospray ionization (ESI) quadrupole-time-of-flight mass spectrometry (QTOF-MS). This approach identifies molecular features in the data as phthalate metabolites via the detection of three structurally significant fragment ions. Then phthalate metabolites are classified into four types based on the presence of additional fragment ions specific to each type. Cleavage mechanisms for each class of phthalate metabolite are proposed based on fragmentation patterns generated at various collision energies (CE). All of the tested phthalate metabolites including oxidative and nonoxidative metabolites produced a fragment ion at m/z 121.0295, representing the deprotonated benzoate ion [C₆H₅COO]^-. Most tested phthalate metabolites can produce a specific ion at m/z 147.0088, the deprotonated o-phthalic anhydride ion. However, phthalate carboxylate metabolites can only produce the [M-H-R]^- ion at m/z 165.0193 and do not produce the fragment at m/z 147.0088. Other phthalate oxidative metabolites (hydroxyl- and oxo-) follow a different fragmentation pathway than nonoxidative metabolites. With this workflow, eight unknown phthalate metabolites were putatively identified in pooled urine, with one identified as a previously unreported metabolite by a combination of the MS/MS spectrum and the predicted retention time. Method detection limits for phthalate metabolites in urine were also estimated.

Environmental endocrine disruptor concentrations in urine samples from Mexican Indigenous women

The Indigenous communities in Mexico show significant degrees of vulnerability to pollution due to the lack of knowledge of health risks, traditions, low levels of support, and restricted access to healthcare. As a result, exposure to environmental endocrine disruptors increases in these populations through plastic components or indoor air pollution. Therefore, the aim of the study was to evaluate the exposure to phthalate metabolites, 1-hydroxypyrene, and bisphenol A through biomonitoring data from indigenous Mexican women. A total of 45 women from the Tocoy community in San Luis Potosí, Mexico, were included. Urine samples were analyzed for Bisphenol A and 4 phthalate metabolites by ultra-performance liquid chromatography couples to tandem mass spectrometry; additionally, the 1-hydroxypyrene concentrations were evaluated by high-performance liquid chromatography coupled to a fluorescence detector. Among the main pollution sources were the use of plastic containers and burning garbage (98-100%). Indigenous women presented an exposure of 100% to mono-2-ethyl phthalate, mono-n-butyl phthalate, and 1-hydroxypyrene, with a median (25th-75th percentiles) of 17,478 (11,362-37,355), 113.8 (61.7-203.5), and 1.2 (0.9-1.7) µg/g creatinine, respectively. The major findings show urinary mono-2-ethyl phthalate concentrations higher than those measured from other studies. Therefore, these results show an impressive exposure to di(2-ethylhexyl) phthalate in Indigenous women. The current study reflects the absence of regulatory policies in marginalized populations. It highlights the need to design strategies that mitigate exposure and the importance of biological monitoring to evaluate and prevent health risk associated with exposure to environmental endocrine disruptors.

Spatial-temporal distributions and influential factors of phthalate acid esters in sediments of three lakes in Inner Mongolia

The spatiotemporal distributions, influential factors, and ecological risks of 15 phthalate acid esters (PAEs) in the sediments of three typical lakes in Inner Mongolia were investigated in this work. PAEs were widespread in all surface sediments ranging from 598.3 to 3873.8 μg/kg dry weight. Average PAE concentrations were highest in the surface sediments of Wuliangsuhai Lake followed by Daihai and Hulun Lakes, which were consistent with population density and intensity of anthropogenic activities. Dibutyl phthalate, di-iso-butyl phthalate (DIBP), and diethyl phthalate (DEP) were the dominant PAEs with similar abundance orders for the three lakes. The cold climate could explain the higher DEP abundance in the sediments of lakes at higher latitudes. The highest Σ PAE and most individual PAE concentrations were located at one of the discharge river estuaries because most PAEs were terrestrial pollutants. Σ PAE concentrations in the core sediments increased with years and fluctuations owing to the increasing PAE usage and input. The second highest PAE concentration peaks were associated with the high gross domestic product growth rates in 2003-2008. Redundancy analysis revealed that butyl benzyl phthalate and diamyl phthalate in the surface sediments of Hulun Lake were principally positively influenced by organic matter (65.6% contribution among geochemical variables), Fe oxides (25.1% contribution among metals), and Mn oxides (23.8% contribution among metals). The DIBP and DEP exhibited high risks to sensitive fish according to a risk quotient assessment. This work presents new insights into PAE status and deposition mechanisms in the lakes within high latitudes or cold climates, and provides important information for future environmental protection and management.

Skin models for dermal exposure assessment of phthalates

Phthalates are a class of compounds that have found widespread use in industrial applications, in particular in the polymer, cosmetics and pharmaceutical industries. While ingestion, and to a lesser degree inhalation, have been considered as the major exposure routes, especially for higher molecular weight phthalates, dermal exposure is an important route for lower weight phthalates such as diethyl phthalate (DEP). Assessing the dermal permeability of such compounds is of great importance for evaluating the impact and toxicity of such compounds in humans. While human skin is still the best model for studying dermal permeation, availability, cost and ethical concerns may preclude or restrict its use. A range of alternative models has been developed over time to substitute for human skin, especially in the early phases of research. These include ex vivo animal skin, human reconstructed skin and artificial skin models. While the results obtained using such alternative models correlate to a lesser or greater degree with those from in vivo human studies, the use of such models is nevertheless vital in dermal permeation research. This review discusses the alternative skin models that are available, their use in phthalate permeation studies and possible new avenues of phthalate research using skin models that have not been used so far.

Epigenetic Regulation in Exposome-Induced Tumorigenesis: Emerging Roles of ncRNAs

Environmental factors, including pollutants and lifestyle, constitute a significant role in severe, chronic pathologies with an essential societal, economic burden. The measurement of all environmental exposures and assessing their correlation with effects on individual health is defined as the exposome, which interacts with our unique characteristics such as genetics, physiology, and epigenetics. Epigenetics investigates modifications in the expression of genes that do not depend on the underlying DNA sequence. Some studies have confirmed that environmental factors may promote disease in individuals or subsequent progeny through epigenetic alterations. Variations in the epigenetic machinery cause a spectrum of different disorders since these mechanisms are more sensitive to the environment than the genome, due to the inherent reversible nature of the epigenetic landscape. Several epigenetic mechanisms, including modifications in DNA (e.g., methylation), histones, and noncoding RNAs can change genome expression under the exogenous influence. Notably, the role of long noncoding RNAs in epigenetic processes has not been well explored in the context of exposome-induced tumorigenesis. In the present review, our scope is to provide relevant evidence indicating that epigenetic alterations mediate those detrimental effects caused by exposure to environmental toxicants, focusing mainly on a multi-step regulation by diverse noncoding RNAs subtypes.

Pregnane X Receptor Mediates Atherosclerosis Induced by Dicyclohexyl Phthalate in LDL Receptor-Deficient Mice

Plastic-associated endocrine disrupting chemicals (EDCs) have been implicated in the etiology of cardiovascular disease (CVD) in humans, but the underlying mechanisms remain elusive. Dicyclohexyl phthalate (DCHP) is a widely used phthalate plasticizer; whether and how exposure to DCHP elicits adverse effects in vivo is mostly unknown. We previously reported that DCHP is a potent ligand of the pregnane X receptor (PXR) which acts as a xenobiotic sensor to regulate xenobiotic metabolism. PXR also functions in macrophages to regulate atherosclerosis development in animal models. In the current study, LDL receptor-deficient mice with myeloid-specific PXR deficiency (PXRΔMyeLDLR-/-) and their control littermates (PXRF/FLDLR-/-) were used to determine the impact of DCHP exposure on macrophage function and atherosclerosis. Chronic exposure to DCHP significantly increased atherosclerotic lesion area in the aortic root and brachiocephalic artery of PXRF/FLDLR-/- mice by 65% and 77%, respectively. By contrast, DCHP did not affect atherosclerosis development in PXRΔMyeLDLR-/- mice. Exposure to DCHP led to elevated expression of the scavenger receptor CD36 in macrophages and increased macrophage form cell formation in PXRF/FLDLR-/- mice. Our findings provide potential mechanisms underlying phthalate-associated CVD risk and will ultimately stimulate further investigations and mitigation of the adverse effects of plastic-associated EDCs on CVD risk in humans.

Gene expression trend changes in breast cancer populations over two decades: insights from The Cancer Genome Atlas database

BACKGROUND

Breast cancer has remained the most common malignancy in women over the past two decades. As lifestyle and living environments have changed, alterations to the disease spectrum have inevitably occurred in this time. As molecular profiling has become a routine diagnostic and objective indicator of breast cancer etiology, we analyzed changes in gene expression in breast cancer populations over two decades using The Cancer Genome Atlas database.

METHODS

We performed Heatmap and Venn diagram analyses to identify constantly up- and down-regulated genes in breast cancer patients of this cohort. We used Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses to visualize associated functional pathways.

RESULTS

We determined that three oncogenes, PD-L2, ETV5, and MTOR and 113 long intergenic non-coding RNAs (lincRNAs) were constantly up-regulated, whereas two oncogenes, BCR and GTF2I, one tumor suppression gene MEN1, and 30 lincRNAs were constantly down-regulated. Up-regulated genes were enriched in "focal adhesion" and "PI3K-Akt signaling" pathways, etc., and down-regulated genes were significantly enriched in "metabolic pathways" and "viral myocarditis". Eight up-regulated genes exhibited doubled or higher expression and the expression of three down-regulated genes was halved or lowered and correlated with long-term survival.

CONCLUSIONS

In this study, we found that gene expression and molecular pathway enrichments are constantly changing with time, importantly, some altered genes were associated with prognostics and are potential therapeutic targets, suggesting that the current molecular subtyping system must be updated to keep pace with this dynamic change.

Diethylhexyl Phthalate and Bisphenol A Promote Vincristine and Tamoxifen Resistance in Vitro

Environmental estrogen active compounds are strong determinants of estrogen receptor (ER)-positive breast cancers, and increased evidence indicates their contribution to chemotherapy resistance. In the current study, the efficacy of vincristine and tamoxifen, with the presence of diethylhexyl phthalate (DEHP) and bisphenol A (BPA) and the possible involvement of estrogen and estrogen receptor-related mechanisms, was evaluated in an ER+ mammary tumor cancer cell line, MCF-7. Chemotherapeutics tamoxifen as an estrogen receptor modulator and vincristine as an antimitotic compound were selected for evaluation against the presence of common endocrine disrupters. BPA and DEHP preincubation at their proliferative concentrations for 4 h was found to decrease the cytotoxicity of vincristine. mRNA and protein expression of ESR1 and ESR 2 were decreased by vincristine, while this decrease was reversed by DEHP and BPA. Both BPA and DEHP were able to interfere with the cytotoxic activity of vincristine against MCF-7 cells through ESR1 and ESR2. This study provides in vitro toxicological evidence for vincristine resistance and its relation to estrogen active environmental pollutants in ER+ breast cancer cells.

Bisphenol A drives di(2-ethylhexyl) phthalate promoting thyroid tumorigenesis via regulating HDAC6/PTEN and c-MYC signaling

Bisphenol A (BPA) and di-(2-ethylhcxyl) phthalate (DEHP) are exist widespread in the environment and produce adverse effect to human as environmental disruptors (EDCs). Epidemiological studies have found that the exposure of DEHP and BPA could increase the susceptibility to thyroid diseases including thyroid cancer and benign thyroid nodules. Due to the existence of multiple pollutants in our daily life, the mixed toxic effects of exposure and their interrelationships may distinguish from the exposure to a single chemical, so it is of great significance to explore the mixed toxic effect of DEHP and BPA co-exposure. Thyroid, as one of the target organs of EDCs, is prone to tumor occurrence, however, whether the mixture of BPA and DEHP will affect the occurrence of thyroid cancer is still obscure. We aim to investigate the effect of single or combined exposure to BPA and DEHP on the occurrence of thyroid cancer. An animal model of exposure to BPA and DEHP was firstly established to evaluate their effect on DMD-induced thyroid cancer. Additionally, human thyroid cancer cells BCPAP and thyroid cells Nthy-ori3-1 were used to further clarify some possible mechanisms of BPA and MEHP, the main metabolite of DEHP. Consequently, we found that BPA alone could increase the incidence of thyroid tumors in female rats compared with DEHP, and DEHP enhanced the effect of BPA on cancer promotion. BPA alone and in combination with DEHP mainly induced the expression of HDAC6, inhibited tumor suppressor gene PTEN upregulated the expression of oncogene c-MYC, and eventually elevate the susceptibility to thyroid tumors. Mechanistically, BPA alone and in combination with MEHP could significantly induce the proliferation of BCPAP cells depending on HDAC6, which could modulate H3K9ac to inhibit PTEN, activate AKT signaling pathway, and simultaneously upregulate the expression of c-MYC. Interestingly, we found that BPA alone and in combination with MEHP could significantly induce the proliferation of Nthy-ori3-1 cells independent on HDAC6 via activating ERK signaling pathway. Taken together, these findings not only provide new evidence of the promoting effect of BPA and DEHP on thyroid cancer but also discusses some possible mechanisms underlying these effects.

Prenatal maternal phthalate exposures and trajectories of childhood adiposity from four to twelve years

BACKGROUND/AIM

Adiposity trajectories reflect dynamic process of growth and may predict later life health better than individual measures. Prenatal phthalate exposures may program later childhood adiposity, but findings from studies examining these associations are conflicting. We investigated associations between phthalate biomarker concentrations during pregnancy with child adiposity trajectories.

METHODS

We followed 514 mother-child pairs from the Mexico City PROGRESS cohort from pregnancy through twelve years. We measured concentrations of nine phthalate biomarkers in 2nd and 3rd trimester maternal urine samples to create a pregnancy average using the geometric mean. We measured child BMI z-score, fat mass index (FMI), and waist-to-height ratio (WHtR) at three study visits between four and 12 years of age. We identified adiposity trajectories using multivariate latent class growth modeling, considering BMI z-score, FMI, and WHtR as joint indicators of latent adiposity. We estimated associations of phthalates biomarkers with class membership using multinomial logistic regression. We used quantile g-computation to estimate the potential effect of the total phthalate mixture and assessed effect modification by sex.

RESULTS

We identified three trajectories of child adiposity, a "low-stable", a "low-high", and a "high-high" group. A doubling of the sum of di (2-ethylhexyl) phthalate metabolites (ΣDEHP), was associated with 1.53 (1.08, 2.19) greater odds of being in the "high-high" trajectory in comparison to the "low-stable" group, whereas a doubling in di-isononyl phthalate metabolites (ΣDiNP) was associated with 1.43 (1.02, 2.02) greater odds of being in the "low-high" trajectory and mono (carboxy-isononyl) phthalate (MCNP) was associated with 0.66 (0.45, 97) lower odds of being in the "low-high" trajectory. No sex-specific associations or mixture associations were observed.

CONCLUSIONS

Prenatal concentrations of urinary DEHP metabolites, DiNP metabolites, and MCNP, a di-isodecyl phthalate metabolite, were associated with trajectories of child adiposity. The total phthalate mixture was not associated with early life child adiposity.

Association between recurrent breast cancer and phthalate exposure modified by hormone receptors and body mass index

The association between phthalate exposure and breast cancer remains controversial. We performed a prospective patient cohort design to explore the interaction between creatinine-corrected urinary phthalate metabolites and hormone receptors as well as body mass index (BMI) on recurrent breast cancer. In this follow-up study, 636 female breast cancer patients and 45 new recurrent cases diagnosed for a total of 1576.68 person-years of follow-up were recruited. Mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP) was negatively associated with breast cancer recurrence, with adjusted hazard ratio (aHR) 3rd vs. 1st quartile of 0.15 (95% CI 0.04–0.51). The MEOHP presented as a non-monotonic dose–response (NMDR) curve, being U-shaped. In the stratification of hormone receptors, MEOHP still exhibited a U-shaped dose–response curve. The third quartile of MEOHP showed significant lowest recurrent risk in the status of ER-positive (aHR 0.18, 95% CI 0.05–0.66), PR-negative (aHR 0.14, 95% CI 0.03–0.63), and HER2-negative (aHR 0.24, 95% CI 0.08–0.76). Whether in BMI < 25 or in BMI ≥ 25, the third quartile of MEOHP was negatively associated with recurrent breast cancer, and there was a negative interaction on an additive scale between MEOHP and BMI (p_interaction = 0.042). The association between MEOHP and recurrent breast cancer was modified by hormone receptors and BMI.

Medication-Associated Phthalate Exposure and Childhood Cancer Incidence

BACKGROUND

Human phthalate exposure is widespread through contact with myriad consumer products. Exposure is particularly high through medications formulated with phthalates. Phthalates disrupt normal endocrine signaling and are associated with reproductive outcomes and incidence of some cancers. We measured associations between gestational and childhood medication-associated phthalate exposures and the incidence of childhood cancers.

METHODS

We identified all live births in Denmark between 1997 and 2017, including both children and birth mothers. Using drug ingredient data merged with the Danish National Prescription Registry, we measured phthalate exposure through filled prescriptions for mothers during pregnancy (gestational exposure) and for children from birth until age 19 years (childhood exposure). Incident childhood cancers were ascertained from the Danish Cancer Registry, and associations were estimated with Cox regression models.

RESULTS

Among 1 278 685 children, there were 2027 childhood cancer cases diagnosed over 13.1 million person-years of follow-up. Childhood phthalate exposure was strongly associated with incidence of osteosarcoma (hazard ratio [HR] = 2.78, 95% confidence interval [CI] = 1.63 to 4.75). We also observed a positive association with incidence of lymphoma (HR = 2.07, 95% CI = 1.36 to 3.14), driven by associations with Hodgkin and non-Hodgkin lymphoma but not Burkitt lymphoma. Associations were apparent only for exposure to low-molecular phthalates, which have purportedly greater biological activity.

CONCLUSIONS

Childhood phthalate exposure was associated with incidence of osteosarcoma and lymphoma before age 19 years. Lingering questions include which specific phthalate(s) are responsible for these associations, by what mechanisms they occur, and to what extent childhood cancer cases could be avoided by reducing or eliminating the phthalate content of medications and other consumer products.