The obstetrics-gynecology community has issued a call to action to prevent toxic environmental chemical exposures and their threats to healthy human reproduction. Recent committee opinions recognize ...that vulnerable and underserved women may be impacted disproportionately by environmental chemical exposures and recommend that reproductive health professionals champion policies that secure environmental justice. Beauty product use is an understudied source of environmental chemical exposures. Beauty products can include reproductive and developmental toxicants such as phthalates and heavy metals; however, disclosure requirements are limited and inconsistent. Compared with white women, women of color have higher levels of beauty product–related environmental chemicals in their bodies, independent of socioeconomic status. Even small exposures to toxic chemicals during critical periods of development (such as pregnancy) can trigger adverse health consequences (such as impacts on fertility and pregnancy, neurodevelopment, and cancer). In this commentary, we seek to highlight the connections between environmental justice and beauty product–related chemical exposures. We describe racial/ethnic differences in beauty product use (such as skin lighteners, hair straighteners, and feminine hygiene products) and the potential chemical exposures and health risks that are associated with these products. We also discuss how targeted advertising can take advantage of mainstream beauty norms to influence the use of these products. Reproductive health professionals can use this information to advance environmental justice by being prepared to counsel patients who have questions about toxic environmental exposures from beauty care products and other sources. Researchers and healthcare providers can also promote health-protective policies such as improved ingredient testing and disclosure for the beauty product industry. Future clinical and public health research should consider beauty product use as a factor that may shape health inequities in women's reproductive health across the life course.
Phthalates are ubiquitous environmental contaminants. Because of potential adverse effects on human health, butylbenzyl phthalate BBzP; metabolite, monobenzyl phthalate (MBzP), di-n-butyl phthalate ...DnBP; metabolite, mono-n-butyl phthalate (MnBP), and di(2-ethylhexyl) phthalate (DEHP) are being replaced by substitutes including other phthalates; however, little is known about consequent trends in population-level exposures.
We examined temporal trends in urinary concentrations of phthalate metabolites in the general U.S. population and whether trends vary by sociodemographic characteristics.
We combined data on 11 phthalate metabolites for 11,071 participants from five cycles of the National Health and Nutrition Examination Survey (2001-2010). Percent changes and least square geometric means (LSGMs) were calculated from multivariate regression models.
LSGM concentrations of monoethyl phthalate, MnBP, MBzP, and ΣDEHP metabolites decreased between 2001-2002 and 2009-2010 percent change (95% CI): -42% (-49, -34); -17% (-23, -9); -32% (-39, -23) and -37% (-46, -26), respectively. In contrast, LSGM concentrations of monoisobutyl phthalate, mono(3-carboxypropyl) phthalate (MCPP), monocarboxyoctyl phthalate, and monocarboxynonyl phthalate (MCNP) increased over the study period percent change (95% CI): 206% (178, 236); 25% (8, 45); 149% (102, 207); and 15% (1, 30), respectively. Trends varied by subpopulations for certain phthalates. For example, LSGM concentrations of ΣDEHP metabolites, MCPP, and MCNP were higher in children than adults, but the gap between groups narrowed over time (pinteraction < 0.01).
Exposure of the U.S. population to phthalates has changed in the last decade. Data gaps make it difficult to explain trends, but legislative activity and advocacy campaigns by nongovernmental organizations may play a role in changing trends.
Zota AZ, Calafat AM, Woodruff TJ. 2014. Temporal trends in phthalate exposures: findings from the National Health and Nutrition Examination Survey, 2001-2010. Environ Health Perspect 122:235-241; http://dx.doi.org/10.1289/ehp.1306681.
Phthalates and bisphenol A (BPA) are widely used industrial chemicals that may adversely impact human health. Human exposure is ubiquitous and can occur through diet, including consumption of ...processed or packaged food.
To examine associations between recent fast food intake and BPA and urinary metabolites of di(2-ethylhexyl) phthalate (ΣDEHPm) and diisononyl phthalate (DiNPm) among the U.S.
We combined data on 8,877 participants from the National Health and Nutrition Examination Survey (NHANES 2003-2010). Using 24-hr dietary recall data, we quantified: a) fast food intake percent of total energy intake (TEI) from fast food; b) fast food-derived fat intake (percent of TEI from fat in fast food); and c) fast food intake by food group (dairy, eggs, grains, meat, and other). We examined associations between dietary exposures and urinary chemical concentrations using multivariate linear regression.
We observed evidence of a positive, dose-response relationship between fast food intake and exposure to phthalates (p-trend < 0.0001) but not BPA; participants with high consumption (≥ 34.9% TEI from fast food) had 23.8% (95% CI: 11.9%, 36.9%) and 39.0% (95% CI: 21.9%, 58.5%) higher levels of ΣDEHPm and DiNPm, respectively, than nonconsumers. Fast food-derived fat intake was also positively associated with ΣDEHPm and DiNPm (p-trend < 0.0001). After adjusting for other food groups, ΣDEHPm was associated with grain and other intake, and DiNPm was associated with meat and grain intake.
Fast food may be a source of exposure to DEHP and DiNP. These results, if confirmed, could inform individual and regulatory exposure reduction strategies.
Zota AR, Phillips CA, Mitro SD. 2016. Recent fast food consumption and bisphenol A and phthalates exposures among the U.S. population in NHANES, 2003-2010. Environ Health Perspect 124:1521-1528; http://dx.doi.org/10.1289/ehp.1510803.
Leukocyte telomere length (LTL) is a putative biological marker of immune system age, and there are demonstrated associations between LTL and cardiovascular disease. This may be due in part to the ...relationship of LTL with other biomarkers associated with cardiovascular disease risk. However, the strength of associations between LTL and adiposity, metabolic, proinflammatory, and cardiovascular biomarkers has not been systematically evaluated in a United States nationally representative population.
We examined associations between LTL and 17 cardiovascular biomarkers, including lipoproteins, blood sugar, circulatory pressure, proinflammatory markers, kidney function, and adiposity measures, in adults ages 20 to 84 from the cross-sectional US nationally representative 1999-2002 National Health and Nutrition Examination Survey (NHANES) (n = 7,252), statistically adjusting for immune cell type distributions. We also examine whether these associations differed systematically by age, race/ethnicity, gender, education, and income. We found that a one unit difference in the following biomarkers were associated with kilobase pair differences in LTL: BMI -0.00478 (95% CI -0.00749--0.00206), waist circumference -0.00211 (95% CI -0.00325--0.000969), percentage of body fat -0.00516 (95% CI -0.00761--0.0027), high density lipoprotein (HDL) cholesterol 0.00179 (95% CI 0.000571-0.00301), triglycerides -0.000285 (95% CI -0.000555--0.0000158), pulse rate -0.00194 (95% CI -0.00317--0.000705), C-reactive protein -0.0363 (95% CI 0.0601--0.0124), cystatin C -0.0391 (95% CI -0.0772--0.00107). When using clinical cut-points we additionally found associations between LTL and insulin resistance -0.0412 (95% CI -0.0685--0.0139), systolic blood pressure 0.0455 (95% CI 0.00137-0.0897), and diastolic blood pressure -0.0674 (95% CI -0.126--0.00889). These associations were 10%-15% greater without controlling for leukocyte cell types. There were very few differences in the associations by age, race/ethnicity, gender, education, or income. Our findings are relevant to the relationships between these cardiovascular biomarkers in the general population but not to cardiovascular disease as a clinical outcome.
LTL is most strongly associated with adiposity, but is also associated with biomarkers across several physiological systems. LTL may thus be a predictor of cardiovascular disease through its association with multiple risk factors that are physiologically correlated with risk for development of cardiovascular disease. Our results are consistent with LTL being a biomarker of cardiovascular aging through established physiological mechanisms.
Numerous methods exist to analyze complex environmental mixtures in health studies. As an illustration of the different uses of mixture methods, we employed methods geared toward distinct research ...questions concerning persistent organic chemicals (POPs) as a mixture and leukocyte telomere length (LTL) as an outcome.
With information on 18 POPs and LTL among 1,003 U.S. adults (NHANES, 2001-2002), we used unsupervised methods including clustering to identify profiles of similarly exposed participants, and Principal Component Analysis (PCA) and Exploratory Factor Analysis (EFA) to identify common exposure patterns. We also employed supervised learning techniques, including penalized, weighted quantile sum (WQS), and Bayesian kernel machine (BKMR) regressions, to identify potentially toxic agents, and characterize nonlinear associations, interactions, and the overall mixture effect.
Clustering separated participants into high, medium, and low POP exposure groups; longer log-LTL was found among those with high exposure. The first PCA component represented overall POP exposure and was positively associated with log-LTL. Two EFA factors, one representing furans and the other PCBs 126 and 118, were positively associated with log-LTL. Penalized regression methods selected three congeners in common (PCB 126, PCB 118, and furan 2,3,4,7,8-pncdf) as potentially toxic agents. WQS found a positive overall effect of the POP mixture and identified six POPs as potentially toxic agents (furans 1,2,3,4,6,7,8-hxcdf, 2,3,4,7,8-pncdf, and 1,2,3,6,7,8-hxcdf, and PCBs 99, 126, 169). BKMR found a positive linear association with furan 2,3,4,7,8-pncdf, suggestive evidence of linear associations with PCBs 126 and 169, and a positive overall effect of the mixture, but no interactions among congeners.
Using different methods, we identified patterns of POP exposure, potentially toxic agents, the absence of interaction, and estimated the overall mixture effect. These applications and results may serve as a guide for mixture method selection based on specific research questions.
Background: Exposure to chemicals during fetal development can increase the risk of adverse health effects, and while biomonitoring studies suggest pregnant women are exposed to chemicals, little is ...known about the extent of multiple chemicals exposures among pregnant women in the United States. Objective: We analyzed biomonitoring data from the National Health and Nutritional Examination Survey (NHANES) to characterize both individual and multiple chemical exposures in U.S. pregnant women. Methods: We analyzed data for 163 chemical analytes in 12 chemical classes for subsamples of 268 pregnant women from NHANES 2003-2004, a nationally representative sample of the U.S. population. For each chemical analyte, we calculated descriptive statistics. We calculated the number of chemicals detected within the following chemical classes: polybrominated diphenyl ethers (PBDEs), perfluorinated compounds (PFCs), organochlorine pesticides, and phthalates and across multiple chemical classes. We compared chemical analyte concentrations for pregnant and nonpregnant women using least-squares geometric means, adjusting for demographic and physiological covariates. Results: The percentage of pregnant women with detectable levels of an individual chemical ranged from 0 to 100%. Certain polychlorinated biphenyls, organochlorine pesticides, PFCs, phenols, PBDEs, phthalates, polycydic aromatic hydrocarbons, and perchlorate were detected in 99-100% of pregnant women. The median number of detected chemicals by chemical class ranged from 4 of 12 PFCs to 9 of 13 phthalates. Across chemical classes, median number ranged from 8 of 17 chemical analytes to 50 of 71 chemical analytes. We found, generally, that levels in pregnant women were similar to or lower than levels in nonpregnant women; adjustment for covariates tended to increase levels in pregnant women compared with nonpregnant women. Conclusions: Pregnant women in the U.S. are exposed to multiple chemicals. Further efforts are warranted to understand sources of exposure and implications for policy making.
Indoor dust is a reservoir for commercial consumer product chemicals, including many compounds with known or suspected health effects. However, most dust exposure studies measure few chemicals in ...small samples. We systematically searched the U.S. indoor dust literature on phthalates, replacement flame retardants (RFRs), perfluoroalkyl substances (PFASs), synthetic fragrances, and environmental phenols and estimated pooled geometric means (GMs) and 95% confidence intervals for 45 chemicals measured in ≥3 data sets. In order to rank and contextualize these results, we used the pooled GMs to calculate residential intake from dust ingestion, inhalation, and dermal uptake from air, and then identified hazard traits from the Safer Consumer Products Candidate Chemical List. Our results indicate that U.S. indoor dust consistently contains chemicals from multiple classes. Phthalates occurred in the highest concentrations, followed by phenols, RFRs, fragrance, and PFASs. Several phthalates and RFRs had the highest residential intakes. We also found that many chemicals in dust share hazard traits such as reproductive and endocrine toxicity. We offer recommendations to maximize comparability of studies and advance indoor exposure science. This information is critical in shaping future exposure and health studies, especially related to cumulative exposures, and in providing evidence for intervention development and public policy.
Polybrominated diphenyl ethers (PBDEs) are brominated flame retardants. Technical mixtures PentaBDE and OctaBDE were phased out in 2004 through voluntary and regulatory actions with DecaBDE remaining ...in limited use until 2013. Biomonitoring studies have shown widespread presence of PBDEs in the US and worldwide population. While some studies suggest that human serum concentrations are declining over time, it is unclear whether this trend will continue. Our objective was to examine temporal trends of PentaBDEs and their hydroxylated metabolites (OH-PBDEs) between 2008 and 2014 in populations of ethnically diverse, pregnant women residing in Northern California (n = 111). Serum samples were collected and analyzed by high resolution mass spectrometry for five PentaBDE congeners and two OH-PBDEs. We found widespread exposures in participants from all three time points (2008/09, 2011/12, 2014). Temporal patterns varied substantially by congener. BDE-47, -99 and the OH-PBDEs decreased between 2008/09-2011/12 but plateaued between 2011/12-2014. In contrast, BDE-100 decreased across all years, BDE-153 decreased in the latter years, and BDE-28 decreased initially and then increased. These findings indicate that while policies to remove PBDEs from the marketplace have successfully lead to declines in exposures to some PBDE congeners, human exposures to these legacy pollutants could plateau and remain ubiquitous in human populations.
•We measured PBDEs and OH-PBDEs in a demographically consistent population of pregnant women over six years.•Between 2008/09 and 2011/12, ∑PBDE5 concentrations decreased 45%, but plateaued between 2011/12 and 2014.•BDE-47 was found in 100% of pregnant women in all years studied.•The BDE-153 concentration decreased more between 2011/12 and 2014 than between the prior cohorts.
Intersectionality is a critical theoretical framework that emphasizes the influence of intersecting systems of oppression on the lived experiences of people marginalized by inequity. Although ...applications of intersectionality are increasing in public health, this framework is absent in environmental health, which has instead focused on the exposome, a paradigm that considers the totality of an individual's environmental exposures across the life course.Despite advancements in the biological complexity of exposome models, they continue to fall short in addressing health inequities. Therefore, we highlight the need for integrating intersectionality into the exposome. We introduce key concepts and tools for environmental health scientists interested in operationalizing intersectionality in exposome studies and discuss examples of this innovative approach from our work on racial inequities in uterine fibroids.Our case studies illustrate how interlocking systems of racism and sexism may affect Black women's exposure to environmental chemicals, their epigenetic regulation of uterine fibroids, and their clinical care. Because health relies on biological and social-structural determinants and varies across different intersectional positions, our proposed framework may be a promising approach for understanding environmental health inequities and furthering social justice.
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