Dietary intake is associated with phthalate body burden in a nationally representative sample

Diethyl phthalate, a plasticizer, induces adipocyte inflammation and apoptosis in mice after long-term dietary administration

The incidence of metabolic diseases is increasing alarmingly in recent times. Parallel to nutritional excess and sedentary lifestyle, the random usage of several endocrine disrupting chemicals including plasticizers is reported to be closely associated with metabolic diseases. Diethyl phthalate (DEP) is a widely used plasticizer in a host of consumer and daily care products. Adipose tissue plays a central role in energy storage and whole-body metabolism. The impairment of adipose function is critically implicated in the pathogenesis of insulin resistance, diabetes, and related metabolic diseases. Recently, exposure to certain phthalate esters has been linked to the development of obesity and diabetes, although there are contradictions and the mechanisms are not clearly understood. In an effort to ascertain the metabolic consequences of chronic phthalate exposure and the underlying mechanism, the present study was designed to examine the effects of long-term dietary consumption of DEP in adipocytes. DEP-treated mice were hyperglycemic but nonobese; their body weight initially increased which subsequently was reduced compared to control. DEP exposure at lower levels impaired adipogenesis by downregulating the key transcription factor, peroxisome proliferator-activated receptor γ and its downstream insulin-sensitizing adipokine, adiponectin, thereby severely compromising adipocyte function. The activation of master regulator nuclear factor κB led to rise in proinflammatory cytokines. We found that DEP triggered intrinsic apoptotic pathways through activated cytochrome c-Apaf1-caspase 9-caspase 3 axis in adipocytes. Taken together, our data revealed that chronic administration of dietary DEP could unleash adverse metabolic outcomes by initiating oxidative stress, inflammation, and apoptosis in the adipocytes, thus leading to adipose tissue dysfunction.

Ultra-processed and fast food consumption, exposure to phthalates during pregnancy, and socioeconomic disparities in phthalate exposures

BACKGROUND

Consuming ultra-processed foods may increase exposure to phthalates, a group of endocrine disruptors prevalent in food contact materials.

OBJECTIVES

Investigate associations between ultra-processed food intake and urinary phthalates during pregnancy, and evaluate whether ultra-processed foods mediate socioeconomic disparities in phthalate exposures.

METHODS

In a socioeconomically diverse sample of 1031 pregnant women from the Conditions Affecting Neurocognitive Development and Learning in Early Childhood (CANDLE) Study in the urban South, the Block Food Frequency Questionnaire was administered and urinary phthalate metabolites were measured in the second trimester. Linear regressions modeled associations between phthalates and overall ultra-processed food consumption, individual ultra-processed foods, and exploratory factor analysis dietary patterns. Causal mediation analyses examined whether ultra-processed food intake mediates relationships between socioeconomic disparities and phthalate exposures.

RESULTS

Ultra-processed foods constituted 9.8-59.0 % (mean = 38.6 %) of participants' diets. 10 % higher dietary proportion of ultra-processed foods was associated with 13.1 % (95 %CI: 3.4 %-22.9 %) higher molar sum concentrations of di(2-ethylhexyl) phthalate metabolites (ΣDEHP). 10 % higher consumption of minimally-processed foods was associated with lower ΣDEHP (10.8 %: 3.4 %-22.9 %). Ultra- and minimally-processed food consumption were not associated with non-DEHP metabolites. Standard deviation higher consumptions of hamburger/cheeseburger, French fries, soda, and cake were associated with 10.5 % (4.2 %-17.1 %), 9.2 % (2.6 %-16.2 %), 7.4 % (1.4 %-13.6 %), and 6.0 % (0.0 %-12.4 %), respectively, higher ΣDEHP. Exploratory factor analysis corroborated positive associations of processed food with ΣDEHP, and uncovered a healthy dietary pattern associated with lower urinary ΣDEHP, mono(2-ethyl-5-hydroxyhexyl) (MEHHP), mono(2-ethyl-5-carboxypentyl) (MECPP), mono(2-carboxymethylhexyl) (MCMHP), and mono-isononyl (MINP) phthalates. Significant indirect effects indicated that lower income and education levels were associated with 1.9 % (0.2 %-4.2 %) and 1.4 % (0.1 %-3.3 %) higher ΣDEHP, respectively, mediated via increased ultra-processed food consumption.

CONCLUSIONS

Consumption of ultra-processed foods may increase exposure to phthalates. Policies to reduce dietary phthalate exposures from food packaging and processing are needed, as socioeconomic barriers can preclude dietary recommendations as a sole means to reduce phthalate exposures.

Reducing Transdermal Uptake of Semivolatile Plasticizers from Indoor Environments: A Clothing Intervention

Models and laboratory studies suggest that everyday clothing influences the transdermal uptake of semivolatile organic compounds, including phthalate plasticizers, from indoor environments. However, this effect has not been documented in environmental exposure settings. In this pilot study, we quantified daily excretion of 17 urinary metabolites (μg/day) for phthalates and phthalate alternatives in nine participants during 5 days. On Day 0, baseline daily excretion was determined in participants' urine. Starting on Day 1, participants refrained from eating phthalate-heavy foods and using personal care products. On Days 3 and 4, participants wore precleaned clothing as an exposure intervention. We observed a reduction in the daily excretion of phthalates during the intervention; mono-n-butyl phthalate, monoisobutyl phthalate (MiBP), and monobenzyl phthalate were significantly reduced by 35, 38, and 56%, respectively. Summed metabolites of di(2-ethylhexyl)phthalate (DEHP) were also reduced (27%; not statistically significant). A similar reduction among phthalate alternatives was not observed. The daily excretion of MiBP during the nonintervention period strongly correlated with indoor air concentrations of diisobutyl phthalate (DiBP), suggesting that inhalation and transdermal uptake of DiBP from the air in homes are dominant exposure pathways. The results indicate that precleaned clothing can significantly reduce environmental exposure to phthalates and phthalate alternatives.

Preconception Phthalate Exposure and Women's Reproductive Health: Pregnancy, Pregnancy Loss, and Underlying Mechanisms

BACKGROUND

Phthalates are endocrine-disrupting chemicals linked to adverse pregnancy outcomes. Despite the sensitivity of female reproductive processes to oxidation-reduction reaction stress and endocrine disruption, evidence for the impact of women's phthalate exposure on the ability to establish and maintain pregnancy has been inconclusive.

OBJECTIVES

We aimed to determine the relationship of preconception phthalate metabolite exposure with a) fecundability and pregnancy loss and b) markers of potential biological mechanisms, including reproductive hormones, inflammation, and oxidative stress.

METHODS

Data were collected from the Effects of Aspirin in Gestation and Reproduction (EAGeR) trial, a preconception study following 1,228 women who were attempting pregnancy, for up to six menstrual cycles and throughout pregnancy if they became pregnant. Twenty phthalate metabolites were measured in a consecutive 3-d pooled urine sample at enrollment. Pregnancy was determined through urinary human chorionic gonadotropin (hCG) at the expected date of menses during each cycle and pregnancy loss as an observed loss following positive hCG. Highly sensitive C-reactive protein (hsCRP) and isoprostanes were measured at enrollment, and reproductive hormones were measured during the follicular phase, ovulation, and luteal phase. Discrete-time Cox proportional hazards models evaluated the relationship of phthalate metabolites with fecundability and weighted Poisson models with robust variance evaluated the risk of pregnancy loss.

RESULTS

An interquartile range (IQR) higher mono-(2-ethylhexyl) phthalate [fecundability odds ratio  ( FOR ) = 0.88 ; 95% confidence interval (CI): 0.78, 1.00], mono-butyl phthalate (FOR = 0.82 ; 95% CI: 0.70, 0.96), and mono-benzyl phthalate (FOR = 0.85 ; 95% CI: 0.74, 0.98) was associated with lower fecundability. No consistent associations were observed with pregnancy loss. Preconception phthalates were consistently associated with higher hsCRP and isoprostanes, as well as lower estradiol and higher follicle-stimulating hormone across the menstrual cycle.

DISCUSSION

Women's preconception exposure to phthalates was associated with lower fecundability, changes in reproductive hormones, and increased inflammation and oxidative stress. The pre- and periconception periods may represent sensitive windows for intervening to limit the reproductive toxicity of phthalate exposure. https://doi.org/10.1289/EHP12287.

Phthalates and Incident Diabetes in Midlife Women: The Study of Women's Health Across the Nation (SWAN)

CONTEXT

Phthalates are hypothesized to contribute to diabetes, but longitudinal evidence in humans is limited.

OBJECTIVE

We examined whether phthalate exposure was associated with a higher incidence of diabetes in a racially/ethnically diverse cohort of midlife women.

METHODS

In the Study of Women's Health Across the Nation Multipollutant Study, we followed 1308 women without diabetes in 1999-2000 for 6 years. Eleven phthalate metabolites were measured in spot urine samples in 1999-2000 and 2002-2003. Incident diabetes was ascertained between 1999-2000 and 2005-2006. Cox proportional hazards models with time-varying exposure were used to estimate the hazard ratio (HR) of diabetes associated with each phthalate metabolite, adjusting for demographic, lifestyle, and health-related factors. Effect modification by race/ethnicity was examined with interaction terms.

RESULTS

Sixty-one women developed diabetes over 6 years (cumulative incidence = 4.7%). Among all women, several high-molecular-weight phthalate metabolites were associated with a higher incidence of diabetes, but none were statistically significant. There was effect modification by race/ethnicity. Among White women, each doubling of the concentrations of mono-isobutyl phthalate (MiBP), monobenzyl phthalate, mono-carboxyoctyl phthalate, mono-carboxyisononyl phthalate (MCNP), and mono(3-carboxypropyl) phthalate was associated with a 30% to 63% higher incidence of diabetes (HR = 1.30, 95% CI, 1.03-1.65 for MCNP; HR = 1.63, 95% CI, 1.18-2.25 for MiBP). In contrast, phthalates were not associated with diabetes incidence in Black or Asian women.

CONCLUSIONS

Some phthalate metabolites were associated with a higher incidence of diabetes over 6 years, but the associations were inconsistent across racial/ethnic groups. Whether phthalates cause diabetes requires further investigation.

Environmental health risks induced by interaction between phthalic acid esters (PAEs) and biological macromolecules: A review

As a kind of compounds abused in industry productions, phthalic acid esters (PAEs) cause serious problems in natural environment. PAEs pollution has penetrated into environmental media and human food chain. This review consolidates the updated information to assess the occurrence and distribution of PAEs in each transmission section. It is found that micrograms per kilogram of PAEs are exposed to humans through daily diets. After entering the human body, PAEs often undergo the metabolic process of hydrolysis to monoesters phthalates and conjugation process. Unfortunately, in the process of systemic circulation, PAEs will interact with biological macromolecules in vivo under the action of non-covalent binding, which is also the essence of biological toxicity. The interactions usually operate in the following pathways: (a) competitive binding; (b) functional interference; and (c) abnormal signal transduction. While the non-covalent binding forces mainly contain hydrophobic interaction, hydrogen bond, electrostatic interaction, and π interaction. As a typical endocrine disruptor, the health risks of PAEs often start with endocrine disorder, further leading to metabolic disruption, reproductive disorders, and nerve injury. Besides, genotoxicity and carcinogenicity are also attributed to the interaction between PAEs and genetic materials. This review also pointed out that the molecular mechanism study on biological toxicity of PAEs are deficient. Future toxicological research should pay more attention to the intermolecular interactions. This will be beneficial for evaluating and predicting the biological toxicity of pollutants at molecular scale.

Interventions to Reduce Exposure to Synthetic Phenols and Phthalates from Dietary Intake and Personal Care Products: a Scoping Review

PURPOSE OF REVIEW

A scoping review was conducted to identify interventions that successfully alter biomarker concentrations of phenols, glycol ethers, and phthalates resulting from dietary intake and personal care product (PCPs) use.

RECENT FINDINGS

Twenty-six interventions in populations ranging from children to older adults were identified; 11 actively removed or replaced products, 9 provided products containing the chemicals being studied, and 6 were education-only based interventions. Twelve interventions manipulated only dietary intake with a focus on bisphenol A (BPA) and phthalates, 8 studies intervened only on PCPs use and focused on a wider range of chemicals including BPA, phthalates, triclosan, parabens, and ultraviolet absorbers, while 6 studies intervened on both diet and PCPs and focused on phthalates, parabens, and BPA and its alternatives. No studies assessed glycol ethers. All but five studies reported results in the expected direction, with interventions removing potential sources of exposures lowering EDC concentrations and interventions providing exposures increasing EDC concentrations. Short interventions lasting a few days were successful. Barriers to intervention success included participant compliance and unintentional contamination of products. The identified interventions were generally successful but illustrated the influence of participant motivation, compliance, ease of intervention adherence, and the difficulty of fully removing exposures due their ubiquity and the difficulties of identifying "safer" replacement products. Policy which reduces or removes EDC in manufacturing and processing across multiple sectors, rather than individual behavior change, may have the greatest impact on population exposure.

Screening for phthalates biomarkers and its potential role in infertility outcomes in Jordan

BACKGROUND

Phthalates are endocrine disrupting chemicals that are used in plastic and personal care products. Phthalate exposure has been linked to reproductive and fertility outcomes.

OBJECTIVES

This study aimed to assess the phthalate exposures using both urinary level of two DEHP metabolites in females and questionnaires. It also aimed to investigate the association between phthalate levels and reproductive and fertility outcomes.

METHODS

325 females with and without fertility problems at gynaecology clinics filled out a questionnaire and provided a urine sample. Urine samples were analyzed for two DEHP metabolites: MEHHP, mono (2-ethyl-5-hydroxyhexyl) phthalate; MEOHP, mono (2-ethyl-5-oxohexyl) phthalate, using an HPLC/MS/MS analytical method.

RESULTS

We observed a significant difference between cases and controls in terms of heating plastic in the microwave and use of skin and eye make-up, sunscreen, and nail polish. Our findings showed that MEOHP exposure is significantly associated with infertility among Jordanian women (Adjusted OR = 1.66, 95% CI: 1.14, 2.40, p-value = 0.002).

SIGNIFICANCE

To the best of our knowledge, our study is the first of its kind done in Jordan to screen for phthalate exposure and investigate its association with infertility. Our study demonstrated high exposure of the Jordanian population to DEHP. It confirms the association between DEHP exposure and infertility.

IMPACT STATEMENT

We measured phthalates in infertile and fertile women, in a community unaware of phthalate sources or its impacts, and with no regulation limits set. We aimed to increase awareness to environmental exposure to phthalates, emphasize the importance of implementation of public health interventions to control and minimize the effects of phthalate exposure and provide a base for further studies and future research to aid in the formation of policies and guidelines for the manufacturing and use of phthalates.

Phthalate exposure is associated with more rapid body fat gain in midlife women: The Study of Women's Health Across the Nation (SWAN) Multi-Pollutant Study

Obesity is a major threat to health, but the etiology of obesity is incompletely understood. Phthalates, synthetic chemicals ubiquitous in the environment, are suspected to have obesogenic effects, but the relationship of phthalates and obesity in humans remains uncertain. We examined whether phthalate exposure was associated with body fat gain in midlife women. We analyzed data from 1369 women in the Study of Women's Health Across the Nation Multi-Pollutant Study. Eleven phthalate metabolites measured in spot urine samples at baseline (1999/2000) were standardized with covariate-adjusted creatinine. Body weight (BW), fat mass (FM) from dual-energy X-ray absorptiometry (DXA), and body fat percentage (BF%) from DXA were measured near-annually until 2016/2017. For each metabolite, linear mixed effects models with time and log2(metabolite) interactions were examined, adjusting for demographic, lifestyle, and menopause-related factors. Analyses were conducted overall and stratified by baseline obesity status. As sensitivity analyses, all analyses were repeated using a second set of metabolites measured in 2002/2003. Higher levels of all metabolites except mono-carboxy-isononyl phthalate were associated with faster increases in BF%. Per doubling of metabolite concentrations, differences in five-year BF% change ranged from 0.03 percentage point (ppt) (95% confidence interval (CI): -0.03, 0.09) for mono-isobutyl phthalate to 0.09 ppt (95% CI: 0.02, 0.16) for mono(3-carboxypropyl) phthalate. Results were similar for FM change, but associations with BW change were mostly null. In stratified analyses by baseline obesity status, positive associations were strongest in women who were normal/underweight at baseline. When metabolites from 2002/2003 were used as exposures, most associations were attenuated and not statistically significant, but they remained positive for normal/underweight women. In conclusion, phthalate metabolites were associated with more rapid body fat gain in midlife women, but our results need confirmation given attenuation of estimates in the sensitivity analyses.

Determinants of urinary phthalate biomarker concentrations in pre- and perimenopausal women with consideration of race

BACKGROUND/OBJECTIVES

Phthalates are endocrine disruptors in consumer plastics and personal care products. Our objectives were to identify determinants of phthalate biomarkers in women during the hormonally-sensitive midlife period, and to consider differences between non-Hispanic White and Black women.

METHODS

We used information from the Midlife Women's Health Study of pre- and peri-menopausal women from Baltimore, Maryland (enrolled 2006-2015). We collected sociodemographic/health information via baseline questionnaires or during clinic visits and measured nine phthalate metabolites in pools of 2-4 urines collected across one menstrual cycle. We calculated molar sums of metabolites to estimate exposure to di(2-ethylhexyl) phthalate (ΣDEHP), personal care product phthalates (ΣPCPs), and phthalates in plastics (ΣPlastics). Accounting for meaningful predictors from bivariable analyses, our multivariable linear regression models evaluated determinants of phthalate biomarkers in all women (n = 689), non-Hispanic White women only (n = 467), or non-Hispanic Black women only (n = 195).

RESULTS

In multivariable analyses of all women, those who were perimenopausal, widowed/divorced, non-Hispanic Black, with higher family income, with lower BMI, or who reported more frequent nausea had higher monoethyl phthalate (MEP) and ΣPCP. Non-Hispanic White women who were perimenopausal had lower mono-(3-carboxypropyl) phthalate (MCPP) and monobutyl phthalate (MBP), those who consume alcohol had higher mono-isobutyl phthalate (MiBP), and those with higher BMI had lower MEP and higher MCPP. Alternatively, widowed/divorced Black women had higher ΣDEHP, monobenzyl phthalate (MBzP), and ΣPlastics, whereas Black women with higher income had higher MEP and ΣPCP. Black women who described themselves as having "as much" physical activity as others or who reported a skin condition had lower MBzP and MCPP, respectively.

CONCLUSION

We identified important determinants of phthalate biomarkers in midlife women and observed some differences by race. Future studies could consider reasons for these differences when developing interventions to reduce phthalate disparities and related health effects.

Phthalates in dormitory dust and human urine: A study of exposure characteristics and risk assessments of university students

Phthalate diesters (PAEs) are prevalent and potentially toxic to human health. The university dormitory represents a typical and relatively uniform indoor environment. This study evaluated the concentrations of phthalate monoesters (mPAEs) in urine samples from 101 residents of university status, and the concentrations of PAEs in dust collected from 36 corresponding dormitories. Di-(2-ethylhexyl) phthalate (DEHP, median: 68.0 μg/g) was the major PAE in dust, and mono-ethyl phthalate (47.9 %) was the most abundant mPAE in urine. The levels of both PAEs in dormitory dust and mPAEs in urine were higher in females than in males, indicating higher PAE exposure in females. Differences in lifestyles (dormitory time and plastic product use frequency) may also affect human exposure to PAEs. Moreover, there were significant positive correlations between the estimated daily intakes of PAEs calculated by using concentrations of PAEs in dust (EDI_D) and mPAEs in urine (EDI_U), suggesting that PAEs in dust could be a significant source of human exposure to PAEs. The value of EDI_D/EDI_U for low molecular weight PAEs (3-6 carbon atoms in their backbone) was lower than that of high molecular weight PAEs. The contribution rate of various pathways to PAE exposure illustrated that non-dietary ingestion (87.8 %) was the major pathway of human exposure to PAEs in dust. Approximately 4.95 % of university students' hazard quotients of DEHP were >1, indicating that there may be some health risks associated with DEHP exposure among PAEs. Furthermore, it is recommended that some measures be taken to reduce the production and application of DEHP.

Phthalate and bisphenol a exposures during pregnancy: Findings from the National Children's Study

Maternal exposure to phthalates and bisphenol A (BPA) during pregnancy can result in many adverse offspring health outcomes. Exposure to phthalates and BPA can vary depending on consumption of certain foods, some of which may vary by race/ethnicity. This study relates urine phthalate and BPA concentrations to sociodemographic and diet data. Concentrations of bisphenol A (BPA) and 11 phthalate metabolites were measured from spot urine at the third trimester visit of a sample of 485 pregnant women from the National Children's Study Vanguard Study Pilot data from seven U.S. cities. At the same time, food frequency questionnaires (FFQ) using the Diet*Calc software were obtained from 313 (65%) participants to assess dietary behavior. Overall, phthalate metabolites were highest among Hispanic women, particularly mBP, miBP, and mECPP, and these disparities were not explained by diet. Participants who did not attend college had higher concentrations of mBP, mBzP, mEP, and miBP, and lower mCOP. These disparities were also not explained by diet. The causes for these disparities should be further studied to reduce potential negative health outcomes associated with phthalate exposure for children of Hispanic or non-college educated women.

Phthalate exposure and DNA oxidative damage in young people of takeaway food lovers

Numerous studies have demonstrated the ubiquitous of phthalates in materials of food and food packaging, and the effects of regular eating takeaway food for a long time on human health and phthalate exposure levels were not fully investigated. A total of 288 college students who love eating takeaway food were recruited to explore phthalate exposure and oxidative stress, by measuring metabolites of traditional or alternative phthalates and 8-hydroxydeoxyguanosine (8-OHdG, a biomarker of DNA oxidative damage) in their urine samples. Both traditional and alternative phthalates were highly detected. Based on weekly frequency of takeaway eating collecting from questionnaire, the students were divided into four groups including level 1 (L1, < 3 times), level 2 (L2, 3-7 times), level 3 (L3, 8-12 times) and level 4 (L4, > 12 times). The total concentrations of all phthalate metabolites were 42.5-893 ng/mL in all students, which were significantly different among four groups, with the lowest level in L1 (p < 0.05). Checking with the generalized linear model (L1 as the reference), the concentrations of most phthalate metabolites increased 12.0-144% in L2 and L3 compared with those in L1. For each group increase, the concentrations of total metabolites, and metabolites of high and low molecular weight phthalates will increase by 0.156%, 0.128%, and 0.142%, respectively. Besides, levels of 8-OHdG (0.639-33.7 ng/mL) were positively correlated with phthalate daily exposure doses. The each increase of a percentage unit of daily exposure of phthalates, the concentrations of 8-OHdG will increase by 0.258-0.405%. However, levels of 8-OHdG were not significantly different among the four groups. The alternative phthalates have already entered the body of Chinese young people. Our results indicated the regular consumption of takeaway food (e.g., more than three times per week) may increase the chance of exposure to certain phthalates, and may not significantly increase the levels of DNA oxidative damage, unless exposed to other pollutants such as phthalates.

Levels and health risks of urinary phthalate metabolites and the association between phthalate exposure and unexplained recurrent spontaneous abortion: a large case-control study from China

Phthalate acid esters (PAEs) are environmental endocrine disruptors that can interfere with endocrine processes and cause adverse reproductive outcomes. The link between PAE exposure and unexplained recurrent spontaneous abortion (URSA) remains unknown. In this study, nine urinary metabolites of PAEs (mPAEs) were measured in 594 URSA cases and 569 healthy controls. The measured mPAEs were ubiquitously detected and present at higher levels (median: 203 ng/mL) in the URSA cases than in the controls (median: 161 ng/mL). Multiple logistic regression analysis showed that URSA was associated with higher concentrations of mono (2-ethyl-5-hydroxyhexyl) phthalate (mEHHP), mono (2-ethylhexyl) phthalate (mEHP), and mono-ethyl phthalate (mEP) and lower concentrations of mono-isobutyl phthalate (miBP). Moreover, a quantile-based g-computation (QGC) model revealed a positive association between mPAEs mixture and URSA. The URSA cases showed significantly higher concentrations of di-(2-ethylhexyl) phthalate (DEHP) than the controls. This was consistent with the health risk assessment, which suggested that DEHP is the main contributors to potential non-carcinogenic risk. DEHP accounted for over 80% of total risk. The large case-control study results suggest that PAE exposure may increase the risk of URSA, and that policy-makers and public health experts should pay more attention to DEHP exposure.

High-Temperature Soup Foods in Plastic Packaging Are Associated with Phthalate Body Burden and Expression of Inflammatory mRNAs: A Dietary Intervention Study

Plastic packaging material is widely used to package high-temperature soup food in China, but this combination might lead to increased exposure to phthalates. The health effects and potential biological mechanisms have not been well studied. This study aimed to examine urinary phthalate metabolites and the expression of inflammatory cytokines in the blood before, during, and after a "plastic-packaged high-temperature soup food" dietary intervention in healthy adults. The results showed that compared with those in the preintervention period, urinary creatinine-adjusted levels of monomethyl phthalate (MMP), mono-n-butyl phthalate (MBP), mono-isobutyl phthalate (MIBP), and total phthalate metabolites in the intervention period were significantly higher, with increases of 71.6, 41.8, 38.8, and 29.8% for MMP, MBP, MIBP, and the total phthalate metabolites, respectively. After intervention, the mean levels of IL-1β, IL-4, and TNF-α mRNA increased by 19.0, 21.5, and 25.0%, respectively, while IL-6 and IFN-γ mRNA decreased by 24.2 and 32.9%, respectively, when compared with the preintervention period. We also observed that several phthalates were associated with the mRNA or protein expression of IL-8, TNF-α, and IL-10. Therefore, consumption of plastic-packaged high-temperature soup food was linked to increased phthalate exposure and might result in significant changes in mRNA expression of several inflammatory cytokines.

A Pilot Study: Nails as a Non-invasive Biospecimen of Human Exposure to Phthalate Esters

Human biomonitoring provides a scientific approach that systematically reveals exposure to phthalates through all possible routes. In this pilot study, fingernail was chosen as a non-destructive biospecimen to assess human exposure to nine phthalates. Concentrations of total phthalates ranged from 17.8 to 176 µg/g (median: 65.4 µg/g). Di(2-ethylhexyl) phthalate, dibutyl phthalate (DBP), and di-isobutyl phthalate were the major compounds found in fingernails, accounting for 64.3%, 19.4%, and 12.9% of the total phthalates, respectively. No significant difference in phthalates concentrations was found among genders and age-related distribution (p > 0.05). The concentration of DBP was positively correlated with participant's body mass index (r = 0.83). Our results suggested that fingernail can be used as a non-invasive biospecimen for the biomonitoring of human exposure to phthalates. Further studies are needed to investigate the relationship between phthalates or their metabolites in fingernail and other biological samples, such as urine and blood.

Dietary correlates of urinary phthalate metabolite concentrations in 6-19 Year old children and adolescents

BACKGROUND

Children are vulnerable to adverse health effects associated with phthalates, and food is one source of exposure. A comprehensive analysis investigating urinary phthalate metabolite concentrations in relation to food type and source has yet to be undertaken.

OBJECTIVES

We use reduced rank regression, a dimension reduction method, to identify dietary patterns associated with urinary phthalate metabolites in children in a large US study.

METHODS

We used data from 2369 participants 6-19 years old from the 2011-2016 National Health and Nutrition Examination Survey who recalled their diet over the 24 h prior to urine collection. We used dietary data to estimate intake and source (i.e., prepared at a restaurant vs. purchased from a grocery store) of 136 food groups. We used reduced rank regression to identify dietary patterns explaining variation in overall urinary concentrations of ∑di-2-ethylhexyl phthalate and seven phthalate metabolites. We also examined pairwise associations between food groups and urinary phthalate metabolites.

RESULTS

We identified eight dietary patterns that cumulatively explained 12.1% of variation in urinary phthalate metabolites, including a dietary pattern characterized by certain starchy vegetables (e.g., plantains and lima beans), quick breads, and citrus juice prepared at a restaurant. A one SD increase in this food pattern score was associated with a 37.2% higher monocarboxyoctyl phthalate (MCOP) concentration (95% CI: 30.3, 44.4). We also observed weak associations between certain food groups and urinary phthalate metabolites (e.g., a one SD increase in intake of certain starchy vegetables prepared at a restaurant was associated with a 1.8% [95% CI: 0.7, 2.8] higher MCOP).

CONCLUSIONS

Children whose diets were characterized by higher consumption of certain starchy vegetables, quick breads, and citrus juices prepared at a restaurant had higher urinary phthalate metabolites. More detailed information on the specific methods of food processing and details on packaging materials is needed.

Longitudinal changes in oxidative stress and early renal injury in children exposed to DEHP and melamine in the 2011 Taiwan food scandal

In 2011, phthalates, mainly di-(2-ethylhexyl) phthalate (DEHP), were found to have been added to a variety of foods in Taiwan, increasing the risk of microalbuminuria in children. Exposure to melamine perhaps modifies that risk. This prospective cohort study investigates whether renal injury resulting from exposure to DEHP-tainted foods from the 2011 Taiwan Food Scandal is reversed over time. The temporal and interactive effects of past daily DEHP intake, current daily DEHP intake, and urinary melamine levels on oxidative stress and renal injury were also examined. Two hundred possibly DEHP-affected children (aged < 18 years) were enrolled in the first survey wave (August 2012-January 2013), with 170 and 159 children in the second (July 2014-February 2015) and third waves (May 2016-October 2016), respectively. The first wave comprised questionnaires that were used to collect information about possible past daily DEHP intake from DEHP-tainted foods. One-spot first morning urine samples were collected to measure melamine levels, phthalate metabolites, and markers indicating oxidative stress (malondialdehyde and 8-oxo-2'-deoxyguanosine), and renal injury (albumin/creatinine ratio (ACR) and N-acetyl-beta-D-glucosaminidase) in all three waves. Generalized estimating equation (GEE) modeling revealed that both past daily DEHP intake and time might affect urinary ACR. However, most interactions were negative and significant correlation was observed only during the second wave (P for interaction = 0.014) in the group with the highest past daily DEHP intake (>50 μg/kg/day). Urinary melamine levels were found to correlate significantly with both urinary ACR and oxidative stress markers. The highest impact associated with exposure to DEHP-tainted foods in increasing urinary ACR of children was observed during the first wave, and the effect may partially diminish over time. These results suggest that continuous monitoring of renal health and other long-term health consequences is required in individuals who were affected by the scandal in 2011.

Dietary intake and household exposures as predictors of urinary concentrations of high molecular weight phthalates and bisphenol A in a cohort of adolescents

BACKGROUND

Phthalates and bisphenol A (BPA) are endocrine disrupting chemicals used in consumer products, building materials, and food processing and packaging materials. They are associated with adverse health outcomes, especially when exposure occurs during heightened windows of susceptibility.

OBJECTIVE

We evaluated the relationship between housing and dietary characteristics and the concentration of several high-molecular-weight (HMW) phthalate metabolites and BPA in a cohort of Latina adolescents.

METHODS

We collected information on recent food consumption and housing characteristics and quantified the concentration of HMW phthalate and BPA metabolites in urine collected at two different time points. We used generalized estimating equations (GEE) to assess predictors of each metabolite.

RESULTS

No significant associations were observed between housing and dietary characteristics and metabolites of di(2-ethylhexyl) phthalate (DEHP) or BPA. In contrast, higher urinary monobenzyl phthalate (MBzP) concentration was associated with living in a home with vinyl or linoleum flooring (66.7% change, p-value <0.01), while higher urinary mono(3-carboxypropyl) phthalate (MCPP) concentration was associated with recent consumption of coffee (47.2% change, p-value <0.01), and fast food (30.3% change, p-value <0.05).

SIGNIFICANCE

These findings may be useful in targeting interventions that reduce phthalate uptake in young adults.

Exposure of men and lactating women to environmental phenols, phthalates, and DINCH

Phthalates and 1,2-Cyclohexane dicarboxylic acid diisononyl ester (DINCH), bisphenols (BPs), parabens (PBs), and triclosan (TCS) are high-production-volume chemicals of pseudo-persistence that are concerning for the environment and human health. This study aims to assess the exposure to 10 phthalates, DINCH, and environmental phenols (3 BPs, 7 PBs, and TCS) of Slovenian men (n = 548) and lactating primiparous women (n = 536). We observed urinary concentrations comparable to studies from other countries and significant differences among the sub-populations. In our study, men had significantly higher levels of phthalates, DINCH, and BPs, whereas the concentrations of PBs in urine were significantly higher in women. The most significant determinant of exposure was the area of residence and the year of sampling (2008-2014) that mirrors trends in the market. Participants from urban or industrialized sampling locations had higher levels of almost all monitored analytes compared to rural locations. In an attempt to assess the risk of the population, hazard quotient (HQ) values were calculated for individual compounds and the chemical mixture. Individual analytes do not seem to pose a risk to the studied population at current exposure levels, whereas the HQ value of the chemical mixture is near the threshold of 1 which would indicate a higher risk. We conclude that greater emphasis on the risk resulting from cumulative exposure to chemical mixtures and additional studies are needed to estimate the exposure of susceptible populations, such as children.

An integrated exposure and pharmacokinetic modeling framework for assessing population-scale risks of phthalates and their substitutes

To effectively incorporate in vitro-in silico-based methods into the regulation of consumer product safety, a quantitative connection between product phthalate concentrations and in vitro bioactivity data must be established for the general population. We developed, evaluated, and demonstrated a modeling framework that integrates exposure and pharmacokinetic models to convert product phthalate concentrations into population-scale risks for phthalates and their substitutes. A probabilistic exposure model was developed to generate the distribution of multi-route exposures based on product phthalate concentrations, chemical properties, and human activities. Pharmacokinetic models were developed to simulate population toxicokinetics using Bayesian analysis via the Markov chain Monte Carlo method. Both exposure and pharmacokinetic models demonstrated good predictive capability when compared with worldwide studies. The distributions of exposures and pharmacokinetics were integrated to predict the population distributions of internal dosimetry. The predicted distributions showed reasonable agreement with the U.S. biomonitoring surveys of urinary metabolites. The "source-to-outcome" local sensitivity analysis revealed that food contact materials had the greatest impact on body burden for di(2-ethylhexyl) adipate (DEHA), di-2-ethylhexyl phthalate (DEHP), di(isononyl) cyclohexane-1,2-dicarboxylate (DINCH), and di(2-propylheptyl) phthalate (DPHP), whereas the body burden of diethyl phthalate (DEP) was most sensitive to the concentration in personal care products. The upper bounds of predicted plasma concentrations showed no overlap with ToxCast in vitro bioactivity values. Compared with the in vitro-to-in vivo extrapolation (IVIVE) approach, the integrated modeling framework has significant advantages in mapping product phthalate concentrations to multi-route risks, and thus is of great significance for regulatory use with a relatively low input requirement. Further integration with new approach methodologies will facilitate these in vitro-in silico-based risk assessments for a broad range of products containing an equally broad range of chemicals.

Origin, Impact, and Solutions for Lifestyle-Related Chronic Diseases in Samoa and American Samoa

Samoa and American Samoa are two island groups in the South Pacific inundated with the physiological consequences of swift westernization of diet and lifestyle. These polities face the singular theme of lifestyle-related problems seen in other countries. This paper aims to discuss the current demographics in Samoa and American Samoa and examine the origin and impact of lifestyle-related chronic diseases within a subset of its populace. This review will highlight the prominent nutrition transition that these polities have undergone in their development and examine the pathogenesis and pathophysiology of lifestyle-related diseases, primarily type 2 diabetes and obesity, in the context of a prominent cultural shift. Samoa and American Samoa face a litany of public health concerns as a result of the rising prevalence of lifestyle-related chronic diseases and the persistent threat of obesity. Lifestyle medicine is proposed as the optimal treatment solution for the currently devastating disease states and is adapted to the vibrant agricultural resources and healing roots of the Samoan culture.

Occurrence and migration of phthalates in adhesive materials to fruits and vegetables

Labels or tapes are widely used on fresh fruits and vegetables, which may contain phthalates (PAEs). There are few studies on the contamination pathway of PAEs from labels or tapes to food stuff. In this study, the concentrations of eleven PAEs in adhesive labels, tapes, labeled fruits and vegetables on the market were investigated. The eleven PAEs were detected with the total concentration of 7.44-30.51 mg/m² in labels and tapes. Diethyl phthalate (DEP), di-n-butyl phthalate (DIBP), dimethyl phthalate (DMP), Bis (2-ethylhexyl) phthalate (DEHP) and di-n-butyl phthalate (DBP) had the highest detection frequency in adhesive material samples. The concentrations of PAEs in labeled fruits were higher than that in unlabeled fruits, especially in the peel, indicating PAEs could transfer from labels or tapes to fruits and vegetables. Furthermore, the migration behaviors of PAEs from labels or tapes to apples, avocados and celery were investigated. It was found that the PAEs could penetrate to apple and avocado pulp through the peel, resulting in the residue of the PAEs in the whole fruit. Unlike apple peel, the thick avocado peel was more difficultly penetrated by the PAEs. Due to the high lipid content, the PAEs distributed more evenly in avocado pulp than in apple pulp. The migrations up to a maximum of 4.16 mg/kg were found for butyl benzyl phthalate (BBP) in avocado peel and up to a maximum of 0.188 mg/kg in avocado pulp. The average migration of the PAEs in celery ranged from 0.3 to 26.1 μg/kg in three days and the low migration might result from the rough surface and less contacting area. These findings suggest that the use of labels or tapes in direct contact may increase the risk of PAEs exposure to humans through fruits and vegetables.

Phthalates exposure is associated with non-alcoholic fatty liver disease among US adults

PURPOSE

Non-alcoholic fatty liver disease (NAFLD) has become the most common liver disease in the western countries. We aimed to ascertain the relationship of urinary phthalates concentrations with presence of NAFLD among US adults.

METHODS

A cross-sectional analysis of data from National Health and Nutrition Examination Survey (NHANES) during 2003-2016 was performed. NAFLD was predicted by Hepatic Steatosis Index (HSI) and US Fatty Liver Index (US FLI), respectively. The logistic regression models were conducted to evaluate associations of urinary phthalates with NAFLD by adjustment for other covariates.

RESULTS

Of the 4206 participants (mean age 47.99 years old; 50.06% men), risk of suspected NAFLD was increased in those with higher concentrations of urinary phthalates. The results of multivariate models suggested that urinary phthalate metabolites MEOHP (odds ratio [OR] = 1.56, 95% confidence interval [CI] = 1.08-2.24), MEHHP (OR = 1.55, 95% CI = 1.09-2.21), MECPP (OR = 1.44, 95% CI = 1.06-1.95) and the mixtures of nine phthalates (OR = 1.58, 95%CI = 1.18-2.11) were positively related to NAFLD defined by HSI; the similar significant associations were observed for MEHHP (OR = 1.98, 95% CI = 1.32-2.97) when NAFLD was determined based upon US FLI ≥30. In subgroup analyses, the positive associations of urinary phthalates concentrations with NAFLD risk remained robust both in males and females, whereas only in individuals aged <60 years.

CONCLUSIONS

Phthalates exposure was independently associated with NAFLD both in males and females, regardless of being defined using HSI or US FLI.

Gestational Phthalate Exposure and Preschool Attention Deficit Hyperactivity Disorder in Norway

Supplemental Digital Content is available in the text.

Prenatal phthalate exposure has been linked to altered neurobehavioral development in both animal models and epidemiologic studies, but whether or not these associations translate to increased risk of neurodevelopmental disorders is unclear. We used a nested case-cohort study design to assess whether maternal urinary concentrations of 12 phthalate metabolites at 17 weeks gestation were associated with criteria for Attention Deficit Hyperactivity Disorder (ADHD) classified among 3-year-old children in the Norwegian Mother, Father and Child Cohort Study (MoBa). Between 2007 and 2011, 260 children in this substudy were classified with ADHD using a standardized, on-site clinical assessment; they were compared with 549 population-based controls. We modeled phthalate levels both linearly and by quintiles in logistic regression models adjusted for relevant covariates and tested for interaction by child sex. Children of mothers in the highest quintile of di-iso-nonyl phthalate (∑DiNP) metabolite levels had 1.70 times the odds of being classified with ADHD compared with those in the lowest quintile (95% confidence interval [CI] = 1.03 to 2.82). In linear models, there was a trend with the sum of di-2-ethylhexyl phthalate metabolites (∑DEHP); each natural log-unit increase in concentration was associated with 1.22 times the odds of ADHD (95% CI = 0.99 to 1.52). In boys, but not girls, mono-n-butyl phthalate exposure was associated with increased odds of ADHD (odds ratio [OR] 1.42; 95% CI = 1.07 to 1.88). Additional adjustment for correlated phthalate metabolites attenuated estimates. These results suggest gestational phthalate exposure may impact the behavior of children as young as 3 years.

Correlates of urinary concentrations of phthalate and phthalate alternative metabolites among reproductive-aged Black women from Detroit, Michigan

BACKGROUND

Phthalates are endocrine-disrupting chemicals that are widely present in consumer products. In the United States, Black women are more highly exposed to phthalates than other racial/ethnic groups, yet information on predictors of phthalate exposure among Black women is limited.

OBJECTIVE

We evaluated the association of demographics, lifestyle, reproductive history, and personal care product use with urinary concentrations of phthalate and phthalate alternative metabolites, using cross-sectional data from a study of 754 Black women from Detroit, Michigan (2010-2012).

METHODS

Women completed questionnaires and provided urine specimens which were analyzed for 16 phthalate and phthalate alternative metabolites. We used linear regression models to estimate mean percentage differences and 95% confidence intervals (CIs) in concentrations across levels of correlates.

RESULTS

Monoethyl phthalate (MEP) and MBP concentrations were positively associated with personal care product use, particularly nail products. Educational attainment was positively associated with high molecular weight phthalate concentrations but inversely associated with monobenzyl phthalate (MBzP) concentrations. Parity was positively associated with MBzP concentrations and inversely associated with concentrations of MEP and high molecular weight phthalates.

SIGNIFICANCE

We found that sociodemographics, reproductive characteristics, and use of certain personal care products were associated with urinary phthalate concentrations among Black women. Our results emphasize the importance of examining exposure determinants among multiply marginalized populations.

Determinants of phthalate exposure among a U.S.-based group of Latino workers

BACKGROUND

Phthalates are endocrine disrupting compounds linked to various adverse health effects. U.S. national biomonitoring data indicate that select minority subgroups may suffer disparate exposures to phthalates. Still, exposures and their respective determinants among these subgroups are not well characterized.

OBJECTIVE

We sought to examine determinants of phthalate exposure in a subsample of US-based Latino adults.

METHODS

We conducted a cross-sectional study on 94 Latino immigrant adults in Maryland. Participants were >18 years of age and working in a service-based industry. We administered an interviewer-administered questionnaire to capture information on potential exposure determinants (e.g., demographic characteristics, consumer product use, and workplace exposures and behaviors) and using HPLC/MS-MS we quantified concentrations of 9 urinary phthalate metabolites: monoethyl phthalate (MEP, diethyl phthalate metabolite); mono-n-butyl phthalate (MBP, di-n-butyl phthalate metabolite); mono-isobutyl phthalate (MiBP, di-isobutyl phthalate metabolite; monobenzyl phthalate (MBzP, benzylbutyl phthalate metabolite); molar sum of di-2-ethylhexyl phthalate or DEHP metabolites [mono-2-ethylhexyl phthalate (MEHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), and mono-(2-ethyl-5-carboxypentyl) phthalate (MECCP)]; and mono(3-carboxypropyl) phthalate (MCPP, a non-specific metabolite of several phthalates including di-n-butyl phthalate and di-n-octyl phthalate). DEHP was analyzed as the molar sum of four metabolites (ΣDEHP = MEHP + MEHHP + MECPP + MEOHP). Spearman correlations, Wilcoxon-Mann-Whitney, and Kruskal-Wallis tests were conducted to assess bivariate associations between metabolite concentrations and potential exposure determinants. Covariates associated with metabolites at p < 0.10 in bivariate analyses were included in multivariable linear regression models to assess the independent effects of predictors on metabolite concentrations.

RESULTS

Uncorrected median phthalate metabolite concentrations were lower in our study population (50% of samples ranged between 1.4 and 23.6 μg/L. While we observed some significant associations with select predictors in our bivariate analysis, select associations were attenuated in multivariable regression models. In our final multivariable linear regression models, we found that use of bleach (β = 1.15, 95%CI:0.30, 2.00) and consumption pasta/rice/noodles (β = 0.87, 95%CI: 0.27, 1.46) was positively associated with MBzP concentrations. MEP concentrations were inversely associated with use of furniture polish (β = -1.17, 95%CI: 2.21, -0.12) and use of scented dryer sheets (β = -1.08, 95%CI: 2.01, -0.14). Lastly, ΣDEHP concentrations were inversely associated with use of degreaser (ßDEHP = -0.65, 95%CI: 1.25, -0.05).

CONCLUSIONS

In this predominantly U.S.-based Central American subsample of adults, we observed lower metabolite concentrations than those previously reported in other U.S. studies and other countries. Our findings could be due, in part, to temporal trends in phthalate exposures and cultural differences related to exposure-related behaviors. While some exposure determinants were identified in our bivariate analyses, results from multivariable regression models did not provide clear results as many associations were attenuated. Environmental exposures may vary within minority subgroups and should be explored further in future studies to further inform exposure mitigation strategies.

Maternal Food and Beverage Consumption Behaviors and Discrepant Phthalate Exposure by Race

Background: Differential exposure to endocrine-disrupting chemicals, including phthalate diesters, may contribute to persistent racial/ethnic disparities in women’s reproductive health outcomes. We sought to characterize sources of gestational exposure to these agents that may differ according to maternal race. Methods: We enrolled pregnant Black (n = 198), including African American, and White (n = 197) women during the second trimester, and measured eight phthalate monoester metabolites in urine. We assessed confounder-adjusted associations between multiple food and beverage consumption habits, summarized using a principal component analysis, as predictors of maternal urinary phthalate metabolite levels, stratified by race. Results: Whites reported significantly greater unprocessed food consumption (42.5% vs. 32.0%; p < 0.001) and storage of food in clear unbreakable plastic containers (66.5% vs. 49.3%; p < 0.001) than Blacks, while Blacks consumed more canned fruits and vegetables (23.5% vs. 12.2%; p < 0.001) than Whites. Using plastics for food storage, microwaving in plastic containers, and using hard plastic water bottles was associated with urinary phthalate concentrations, especially DEHP metabolites (e.g., mean difference = 5.13%; 95% CI: 3.05, 7.25). These associations were driven primarily by Black pregnant women. Conclusions: Targeted interventions to reduce maternal exposure to phthalates need to be designed with specific attention to differences in food and beverage consumption behaviors among Black and White women.

Exposure to phthalates is associated with grip strength in US adults

The potential association of exposure to phthalates with muscle strength was reported in previous animal experiments. However, their association was rarely directly investigated in general populations. Thus, we aimed to ascertain the association of exposure to phthalates with grip strength using cross-sectional analysis which included 2436 individuals aged ≥ 20 years from the National Health and Nutrition Examination Survey (NHANES) during 2011-2014. The multivariable linear regression models were performed with the adjustment of related covariates. The results suggested that a one-unit increase in log-transformed phthalate metabolites (μg/g creatinine) was inversely associated with grip strength, including Mono-(2-ethyl)-hexyl phthalate (β: -2.727 kg, 95% CI: -3.452, -2.002), Mono-(2-ethyl-5-hydroxyhexyl) phthalate (β: -3.721 kg, 95% CI: -4.836, -2.607), Mono-(2-ethyl-5-oxohexl) phthalate (β: -4.669 kg, 95% CI: -5.761, -3.577), Mono-2-ethyl-5-carboxypentyl phthalate (β: -4.756 kg, 95% CI: -5.957, -3.554), Mono-carboxyoctyl phthalate (β: -1.324 kg, 95% CI: -2.412, -0.235), Mono-carboxynonyl phthalate (β: -2.036 kg, 95% CI: -3.185, -0.886), Mono-benzyl phthalate (β: -2.940 kg, 95% CI: -3.853, -2.026), Mono-n-butyl phthalate (β: -2.100 kg, 95% CI: -3.474, -0.726), Mono-isobutyl phthalate (β: -2.982 kg, 95% CI: -4.331, -1.633), and Mono-ethyl phthalate (β: -1.709 kg, 95% CI: -2.368, -1.050). In subgroup analyses, the associations remained largely unchanged when the samples were stratified by gender and age; However they became ambiguous among underweight subjects when the samples were stratified by BMI status. Overall, exposure to phthalates was inversely associated with grip strength among US adults, regardless of their genders and ages. The suggestive potential BMI status-specific effects of phthalates on grip strength were observed.

Endocrine disrupting chemicals during diet-induced weight loss - A post-hoc analysis of the LOWER study

The link between exposure to endocrine disrupting chemicals (EDCs) and the rapid increase in prevalence of obesity has recently been suggested. However, the magnitude and health impact of EDC exposure in at-risk populations remain largely unclear. In this study, we investigated the effect of a dietary intervention driven reduction in adipose tissue on the magnitude of urinary EDC exposure and mobilization, and whether higher EDC exposure leads to impaired weight loss in obese individuals. In this post-hoc analysis of the Lifestyle, OverWeight, Energy Restriction (LOWER) study from the Netherlands, 218 subjects were included. Five parabens, three bisphenols and thirteen metabolites of eight phthalates were measured in 24-h urine using LC-MS/MS, before and after three-months of a calory-restricted weight reduction intervention program. Associations between adiposity-related traits and EDCs were tested using multivariable linear regression and linear mixed effects models. A multiple testing correction based on the false discovery rate (FDR) was applied. After the 3-month intervention, urinary paraben and bisphenol excretions remained similar. Excretions of mono-butyl phthalates and most high-molecular-weight phthalates decreased, whereas mono-ethyl phthalate increased (all FDR<0.05). A reduction in adipose tissue was not associated with higher urinary EDC excretions. Higher baseline EDC excretions were associated with higher post-intervention body-mass index (methyl-, propylparaben), waist circumference (propylparaben, mono-n-butyl phthalate, mono-benzyl phthalate), and body fat percentage (mono-ethyl phthalate, mono-benzyl phthalate). Associations between parabens and body-mass index, and mono-benzyl phthalate and waist circumference and body fat percentage remained after multiple testing correction (all FDR<0.05). In a study of obese participants, we observed a reduction in most phthalates after a weight reduction intervention. A reduction in adipose tissue may not lead to mobilization and successively to higher urinary EDC excretions. Higher baseline paraben and phthalate exposures were associated with reduced weight loss, suggesting obesogenic properties.

Environmental Pollution and Chronic Kidney Disease

Chronic kidney disease (CKD) is a global public health problem associated with high rates of morbidity and mortality due to end-stage renal disease and cardiovascular disease. Safe and effective medications to reverse or stabilize renal function in patients with CKD are lacking, and hence it is important to identify modifiable risk factors associated with worsening kidney function. Environmental pollutants, including metals, air pollutant, phthalate and melamine can potentially increase the risk of CKD or accelerate its progression. In this review, we discuss the epidemiological evidence for the association between environmental pollution and kidney disease, including heavy metals, air pollution and other environmental nephrotoxicants in the general population.

Phthalate exposure and semen quality in infertile male population from Tianjin, China: Associations and potential mediation by reproductive hormones

Global decline in male fertility and their associations with ubiquitous exposure of phthalates (PAEs) have raised public concerns. However, the current epidemiological data are limited and controversial. Hence, we investigated possible associations between PAE exposure and male infertility. Eleven phthalate metabolites (mPAEs) were determined in urine and serum samples collected from eighty-eight males diagnosed with infertility from Tianjin, China. The median serum levels of mPAE were n.d. -3.63 ng/mL, which were 1-2 orders of magnitude lower than the urinary levels of n.d. -192 ng/mL. Negative associations were identified between urinary follicle-stimulating hormone (FSH) and MiBP and serum MCMHP, as well as testosterone (T) and luteinizing hormone (LH) and the molar concentrations of ∑mPAE, while positive association was found between T and the serum molar concentrations of ∑mDEHP. Positive associations were found between the molar concentrations of serum ∑mPAE and sperm concentration, sperm motility rate, and progressive motility, between mono (2-ethyl-5-carboxypentyl) phthalate (MECPP) and semen volume and total sperm number, and between MCMHP and progressive motility, while negative association was found between mono(2-ethyl-5-oxohexyl) phthalate (MEOHP) and progressive motility. Moreover, FSH was found to mediate the association between serum concentrations of MCMHP and progressive motility (mediation ratio = 41.6%), and LH to mediate the associations between serum concentrations of ∑mPAE and sperm concentration (mediation ratio = 45.7%) and sperm motility rate (mediation ratio = 29.0%). These results also suggested that serum levels of mPAE are a good predictor for male infertility. Further efforts need to be made on toxicological studies to systematically elaborate the internal mechanisms.

Serially assessed bisphenol A and phthalate exposure and association with kidney function in children with chronic kidney disease in the US and Canada: A longitudinal cohort study

BACKGROUND

Exposure to environmental chemicals may be a modifiable risk factor for progression of chronic kidney disease (CKD). The purpose of this study was to examine the impact of serially assessed exposure to bisphenol A (BPA) and phthalates on measures of kidney function, tubular injury, and oxidative stress over time in a cohort of children with CKD.

METHODS AND FINDINGS

Samples were collected between 2005 and 2015 from 618 children and adolescents enrolled in the Chronic Kidney Disease in Children study, an observational cohort study of pediatric CKD patients from the US and Canada. Most study participants were male (63.8%) and white (58.3%), and participants had a median age of 11.0 years (interquartile range 7.6 to 14.6) at the baseline visit. In urine samples collected serially over an average of 3.0 years (standard deviation [SD] 1.6), concentrations of BPA, phthalic acid (PA), and phthalate metabolites were measured as well as biomarkers of tubular injury (kidney injury molecule-1 [KIM-1] and neutrophil gelatinase-associated lipocalin [NGAL]) and oxidative stress (8-hydroxy-2'-deoxyguanosine [8-OHdG] and F2-isoprostane). Clinical renal function measures included estimated glomerular filtration rate (eGFR), proteinuria, and blood pressure. Linear mixed models were fit to estimate the associations between urinary concentrations of 6 chemical exposure measures (i.e., BPA, PA, and 4 phthalate metabolite groups) and clinical renal outcomes and urinary concentrations of KIM-1, NGAL, 8-OHdG, and F2-isoprostane controlling for sex, age, race/ethnicity, glomerular status, birth weight, premature birth, angiotensin-converting enzyme inhibitor use, angiotensin receptor blocker use, BMI z-score for age and sex, and urinary creatinine. Urinary concentrations of BPA, PA, and phthalate metabolites were positively associated with urinary KIM-1, NGAL, 8-OHdG, and F2-isoprostane levels over time. For example, a 1-SD increase in ∑di-n-octyl phthalate metabolites was associated with increases in NGAL (β = 0.13 [95% CI: 0.05, 0.21], p = 0.001), KIM-1 (β = 0.30 [95% CI: 0.21, 0.40], p < 0.001), 8-OHdG (β = 0.10 [95% CI: 0.06, 0.13], p < 0.001), and F2-isoprostane (β = 0.13 [95% CI: 0.01, 0.25], p = 0.04) over time. BPA and phthalate metabolites were not associated with eGFR, proteinuria, or blood pressure, but PA was associated with lower eGFR over time. For a 1-SD increase in ln-transformed PA, there was an average decrease in eGFR of 0.38 ml/min/1.73 m2 (95% CI: -0.75, -0.01; p = 0.04). Limitations of this study included utilization of spot urine samples for exposure assessment of non-persistent compounds and lack of specific information on potential sources of exposure.

CONCLUSIONS

Although BPA and phthalate metabolites were not associated with clinical renal endpoints such as eGFR or proteinuria, there was a consistent pattern of increased tubular injury and oxidative stress over time, which have been shown to affect renal function in the long term. This raises concerns about the potential for clinically significant changes in renal function in relation to exposure to common environmental toxicants at current levels.

Occurrence and distribution of microplastics-sorbed phthalic acid esters (PAEs) in coastal psammitic sediments of tropical Atlantic Ocean, Gulf of Guinea

Baseline microplastic pollution and the occurrence, spatial distribution and ecological risk of microplastic-sorbed phthalate esters (PAEs) in littoral sandflat sediments of the Gulf of Guinea were investigated. A total of 150 sediment samples were collected using a 0.5 × 0.5 × 0.2 m quadrant placed along designated high, drift and current waterlines at five (5) beaches. Analysis for 6 PAEs-sorbed to microplastics (MPs) was carried out using gas chromatography - mass spectrometry (GC-MS). Microplastic particles (1-5 mm) were identified visually and FTIR spectroscopy was also used for identification. The MPs distribution was variably heterogenous with a total of 3424 particles per m² found within the drift and high waterlines across all sites. Results indicated fragments as the dominant microplastic type compared to pellets and fibres. Polyethylene terephthalate was the major polymer type and accounted for a weighted average of 41% of the total plastics, followed by polystyrene (28%), and polypropylene (21%). The ∑₆PAEs concentration ranged from BDL to 164.09 mg/kg dw, dominated by di(2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DnBP), and dimethyl phthalate. The preliminary ecological risk assessment of PAEs in the microplastic fraction, RQ_mp, showed DEHP and DnBP may present medium to high biological risks to marine organisms, suggesting that future study of PAEs in total sediment versus the MP fraction might be useful to refine ecological risk assessments. Land-based anthropogenic activities are primary sources of MPs, whereas oceanographic peculiarities of the area constitute the major distribution driving force.

Effects of fast food packaging plasticizers and their metabolites on steroid hormone synthesis in H295R cells

The health risks of exposure to plasticizers have received widespread attention, however, little is known about the effects of fast food packaging plasticizers on steroid hormone synthesis. In the present study, the types and migration of plasticizers in some commonly used fast-food packaging materials were detected by GC-MS, and the interference effects of these plasticizers and their metabolites on steroid hormone synthesis in the human body were evaluated by the H295R steroidogenesis assay. The GC-MS results showed that the main plasticizer compounds that migrated from fast food packaging into food were di(2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP) and bis(2-ethylhexyl) adipate (DEHA). Exposure to these chemicals (100-1000 μM) can significantly reduce the viability of H295R cells in a dose-response manner, and these plasticizers and their metabolites that migrated into oily foods at high temperatures (0.25-25 μM) could significantly increase the E2 level and reduce the T level in H295R cells. According to the qRT-PCR data, 0.25 to 25 μM mono(2-ethylhexyl) phthalate (MEHP) significantly upregulated the expression levels of 17β-HSD1 and CYP19A1, and downregulated those of CYP17A1, CYP11A1 and StAR. The Western blot results were consistent with those of qRT-PCR. In summary, these results indicated that even exposure to low concentrations (≤1 mg/l or 2.5 μM) of these chemicals and their metabolites can cause significant endocrine-disrupting effects.

Phthalates: Relationships between Air, Dust, Electronic Devices, and Hands with Implications for Exposure

Exposure to phthalates is pervasive and is of concern due to associations with adverse health effects. Exposures and exposure pathways of six phthalates were investigated for 51 women aged 18-44 years in Ontario, Canada, based on measured phthalate concentrations in hand wipes and indoor media in their residences. All six phthalates had detection frequencies of 100% in air (∑₆670 ng m^-3 geomean) and floor dust (∑₆630 μg g^-1), nearly 100% detection frequencies for hand palms and backs that were significantly correlated and concentrations were repeatable over a 3 week interval. Phthalates on hands were significantly correlated with levels in air and dust, as expected according to partitioning theory. Total exposure was estimated as 4860 ng kg bw^-1 day^-1 (5th and 95th percentiles 1980-16 950 ng kg bw^-1 day^-1), with dust ingestion, followed by hand-to-mouth transfer, as the dominant pathways. With the exception of diethyl phthalate (DEP), phthalates had over 50% detection frequencies in surface wipes of most electronic devices sampled, including devices in which the use of phthalates was not expected. Phthalate concentrations on surfaces of hand-held devices were ∼10 times higher than on non-hand-held devices and were correlated with levels on hands. The data are consistent with phthalate emissions from sources such as laminate flooring and personal care products (e.g., scented candles), followed by partitioning among air, dust, and surface films that accumulate on electronic devices and skin, including hands. We hypothesize that hands transfer phthalates from emission sources and dust to hand-held electronic devices, which accumulate phthalates due to infrequent washing and which act as a sink and then a secondary source of exposure. The findings support those of others that exposure can be mitigated by increasing ventilation, damp cloth cleaning, and minimizing the use of phthalate-containing products and materials.

Occurrence of phthalic acid esters in marine organisms from Hangzhou Bay, China: Implications for human exposure

Owing to the wide application of phthalic acid esters (PAEs) in the manufacturing of plastic products, they are ubiquitous in the marine environment. However, the occurrence of various PAEs in marine organisms from China has not been well characterized. In this study, 341 marine organism samples (including fish, shrimp, crab, and shellfish) were collected from Hangzhou Bay, China and analyzed for 16 PAEs. Further, the human PAE exposure risks raised from the consumption of marine organisms were evaluated for adults and children. In total, eight PAEs were detected in collected organism samples, with the concentration of total PAEs (∑PAEs) ranging from 64 to 2840 ng/g (mean 238 ng/g). Crab (mean 811 ng/g) samples had the highest mean concentration of ∑PAEs, followed by fish (465 ng/g), shrimp (293 ng/g), and shellfish (261 ng/g) samples. Among detected PAEs, di-isobutyl phthalate (DiBP), di-n-butyl phthalate (DBP), and di-ethylhexyl phthalate (DEHP) were the predominant PAEs, and they collectively accounted for 84-97% of the ∑PAEs concentrations in all samples. The estimated daily intakes of DiBP, DBP, and DEHP were more than one order of magnitude higher than remaining PAEs. Calculated hazard quotient values of PAEs were all <0.1, suggesting non-cancer risks for the general population through the consumption of marine organisms. Overall, for the first time, this study systematically examined the occurrence of multiple PAEs in four types of marine organisms from Hangzhou Bay, China.

Distribution and risk assessment of phthalates in water and sediment of the Pearl River Delta

Phthalate esters (PAEs) are widely used industrial raw materials that are well known for their environmental contamination and toxicological effects as "endocrine disruptors." In this study, environmental levels of PAEs and eco-toxicological risk assessments were determined in the eight estuaries of the Pearl River (Estuaries), main upstream tributary (Xijiang River), urban river network (River network), and nature reserve reservoir (Reservoirs). Water and sediment samples from the above water systems were collected during the low-water period (May) and the high-water period (August) between 2012 and 2014. Solid phase and ultrasonic methods were used to extract 14 different PAEs that were analyzed by gas chromatography. The analytical average recovery of PAEs in water and sediment was 75.4% ± 4.9% and 121.5% ± 8.9%, respectively. The results showed that PAEs were detected in all of the samples, and the di-n-butyl phtalate (DBP) and benzyl butyl phthalate (BBP) monomers had a detection rate of 100% in water. Similarly, in sediment samples, the detection rates of diisobutyl phthalate (DiBP), DBP, dimethoxyethyl phthalate (DMEP), BBP, di-n-octyl phthalate (DnOP), and DNP ranged from 66.7 to 100%. Among these, in sediment samples, di(2-ethylhexyl) phthalate (DEHP) and phthalic acid bis(2-butoxyethyl) ester (DBEP) had detection rates of 95.8% to 100% in the Estuaries, Xijiang River, and River network. The concentrations of Σ₁₄PAEs in water samples and sediments ranged from 12.95 ± 1.97 to 6717.29 ± 112.37 ng/L and 71.99 ± 8.72 to 17,340.04 ± 227.83 ng/g-dw, respectively. During the low-water period, the average concentration of Σ₁₄PAEs in water and sediment was 1159.58 ± 97.22 ng/L and 2842.50 ± 178.21 ng/g-dw, respectively, and during the high-water period, 822.83 ± 53.19 ng/L and 1936.42 ± 111.31 ng/g-dw, respectively. In water, the average concentration of Σ₁₄PAEs in 2013 and 2014 was 963.39 ± 19.55 ng/L and 2815.35 ± 176.32 ng/L, respectively. In sediment, the average concentrations of Σ₁₄PAEs in 2012 to 2014 were 990.10 ± 23.33 ng/g-dw, 1084.20 ± 112.12 ng/g-dw, and 1816.89 ± 79.97 ng/g-dw, respectively, with concentrations showing an increasing trend year after year (2014 > 2013 > 2012). Potential risk assessment of water ecological, the results show that exceeding environmental risk level (ERL) value in higher molecular weight plasticizer (DEHP, DMEP, DNOP, DNP) was mainly distributed in water, the lower molecular weight plasticizer (BMP, DiBP) was mainly distributed in sediment.

Children's exposure to phthalates and non-phthalate plasticizers in the home: The TESIE study

BACKGROUND

Phthalates and their potential replacements, including non-phthalate plasticizers, are ubiquitous in home environments due to their presence in building materials, plastics, and personal care products. As a result, exposure to these compounds is universal. However, the primary pathways of exposure and understanding which products in the home are associated most strongly with particular exposures are unclear.

OBJECTIVES

We sought to investigate the relationships between phthalates and non-phthalate plasticizers in paired samples of house dust, hand wipes, and their corresponding metabolites in children's urine samples (n = 180). In addition, we compared product use or presence of materials in the household against all compounds to investigate the relationship between product use or presence and exposure.

METHODS

Children aged 3-6 years provided hand wipe and urine samples. Questionnaires were completed by mothers or legal guardians to capture product use and housing characteristics, and house dust samples were collected from the main living area during home visits.

RESULTS

Phthalates and non-phthalate replacements were detected frequently in the environmental matrices. All urine samples had at least 13 of 19 phthalate or non-phthalate replacement metabolites present. Hand wipe mass and dust concentrations of diisobutyl phthalate, benzyl butyl phthalate (BBP), bis(2-ethylhexyl) phthalate, and di-isononyl phthalate were significantly associated with their corresponding urinary metabolites (r_s = 0.18-0.56, p < 0.05). Bis(2-ethylhexyl) terephthalate (DEHTP) in dust was also significantly and positively correlated with its urinary metabolites (r_s = 0.33, p < 0.001). Vinyl flooring was most significantly and positively associated with particular phthalate exposures (indicated by concentrations in environmental matrices and urinary biomarkers). In particular, children who lived in homes with 100% vinyl flooring had urinary concentrations of monobenzyl phthalate, a BBP metabolite, that were 15 times higher than those of children who lived in homes with no vinyl flooring (p < 0.0001). Levels of BBP in hand wipes and dust were 3.5 and 4.5 times higher, respectively, in those homes with 100% vinyl flooring (p < 0.0001 for both).

CONCLUSIONS

This paper summarizes one of the most comprehensive phthalate and non-phthalate plasticizer investigation of potential residential exposure sources conducted in North America to date. The data presented herein provide evidence that dermal contact and hand-to-mouth behaviors are important sources of exposure to phthalates and non-phthalate plasticizers. In addition, the percentage of vinyl flooring is an important consideration when examining residential exposures to these compounds.

Phthalate Metabolites, Hydroxy-Polycyclic Aromatic Hydrocarbons, and Bisphenol Analogues in Bovine Urine Collected from China, India, and the United States

Human exposure to endocrine-disrupting chemicals (EDCs) has aroused considerable public concern over the last three decades. Nevertheless, little is known with regard to the exposure of EDCs in farm animals. In this study, concentrations of 22 phthalate metabolites (PhMs), 15 hydroxylated polycyclic aromatic hydrocarbons (OH-PAHs), and 8 bisphenols (BPs) were determined in 183 bovine urine samples collected from China, India, and the United States. The median concentrations of urinary PhMs, OH-PAHs, and BPs in bovines, collectively, were 66, 4.6, and 16 ng/mL, respectively. Mono-n-butyl phthalate (mBP; median, 14 ng/mL) and ∑₄DEHP (four secondary metabolites of di(2-ethylhexyl) phthalate; 13 ng/mL) were the dominant PhMs; hydroxy-fluorene (OH-Fluo; 1.2 ng/mL) and -phenanthrene (OH-Phen; 1 ng/mL) were the dominant OH-PAHs; and 4,4'-di-hydroxydiphenylmethane (BPF; 10 ng/mL) and 2,2-bis(4-hydroxyphenyl) propane (BPA; 6.7 ng/mL) were the dominant BPs. Bovine urine samples from India and China contained the highest concentrations of PhMs and OH-PAHs, whereas those from India and the United States contained the highest concentrations of BPs. PhM and OH-PAH concentrations were significantly higher in the urine of bulls than those of cows; no such difference was found for BPs. Our findings establish baseline exposure information about three classes of EDCs in domestic farm animals.

Contribution of phthalates and phthalate monoesters from drinking water to daily intakes for the general population

Although phthalates (PAEs) are ubiquitous in drinking water, and phthalate monoesters (MPAEs) have been recognized as the bioactive metabolites of PAEs, little information is available regarding the occurrence of MPAEs in drinking water and the contributions of PAEs and MPAEs to human exposure. In this study, the concentrations of PAEs and MPAEs in 146 samples of drinking water collected from 24 cities throughout China were determined. The mean concentrations of dimethyl phthalate (DMP), diethyl phthalate (DEP), diisobutyl phthalate (DiBP), di-n-butyl phthalate (DnBP), and di-2-ethylhexyl phthalate (DEHP) were 14.31 ± 26.28, 5.905 ± 11.57, 103.8 ± 310.5, 595.9 ± 1794, and 178.2 ± 422.0 ng/L, respectively. Monomethyl phthalate (MMP), monoethyl phthalate (MEP), monoisobutyl phthalate (MiBP), mono-n-butyl phthalate (MnBP), and mono-2-ethylhexyl phthalate (MEHP) were detected in drinking water for the first time, at mean concentrations of 12.1 ± 18.0, 2.4 ± 5.8, 11.3 ± 37.2, 36.3 ± 103, and 9.9 ± 18.0 ng/L, respectively. The geometric mean concentrations of MMP, MEP, MiBP, MnBP, and MEHP in urine samples collected from 1040 participants from 16 cities were 10.1, 19.3, 29.6, 47.3, and 3.63 μg/g creatinine, respectively. The concentrations of PAEs and MPAEs in drinking water and daily intakes (DIs) of PAEs from nine cities where drinking water and urine samples were simultaneously collected were used to estimate the contributions from drinking water. The percentages of DMP, DEP, DiBP, DnBP, and DEHP from drinking water accounted for DIs of 0.60%, 0.049%, 1.26%, 2.76%, and 0.56%, respectively. The percentages of MMP, MEP, MiBP, MnBP and MEHP via intake of drinking water accounted for urinary concentrations of 0.86%, 0.032%, 0.14%, 0.089%, and 0.045%, respectively.

Fetal growth in environmental epidemiology: mechanisms, limitations, and a review of associations with biomarkers of non-persistent chemical exposures during pregnancy

BACKGROUND

Non-persistent chemicals, such as phthalates, environmental phenols, organophosphate pesticides, and others, are challenging to study because of their ubiquity in the environment, diverse exposure routes, and high temporal variability of biomarkers. Nonetheless, there is interest in understanding how gestational exposure to these chemicals may affect fetal growth, as perturbations to normal fetal growth are related to a plethora of adverse health outcomes in childhood and adulthood.

METHODS

The purpose of this review is to describe the state of the science on this topic. We searched PubMed for studies that included both 1) biomarkers of non-persistent chemicals collected during pregnancy and 2) fetal growth outcomes measured at birth (e.g., birth weight) or by ultrasound in utero (e.g., estimated fetal weight).

RESULTS

The bulk of the literature we found uses biomarkers measured at a single time point in pregnancy and birth weight as the primary measure of fetal growth. There is a small, but growing, body of research that uses ultrasound measures to assess fetal growth during pregnancy. In addition to summarizing the findings of the publications we identified, we describe inconsistencies in methodology, areas for improvement, and gaps in existing knowledge that can be targeted for improvement in future work. This literature is characterized by variability in methodology, likely contributing to the inconsistency of results reported. We further discuss maternal, placental, and fetal pathways by which these classes of chemicals may affect fetal growth.

CONCLUSIONS

To improve understanding of how everyday chemical exposures affect fetal growth, and ultimately lifelong health outcomes, mechanisms of toxicant action should be considered alongside improved study designs for future hypothesis-driven research.

Interaction between diet- and exercise-lifestyle and phthalates exposure on sex hormone levels

Phthalate can affect sex hormones secretion. Exercise and diet habits affect sex hormones levels. However, interaction of phthalates exposure and diet or exercise habits with sex hormones is unclear. We enrolled 106 residents aged 11-88 years (48 males and 58 females) from two communities, Wuhan city, China during the winter of 2014 and summer of 2015. Data were collected on socio-demographic characteristics and lifestyle by a questionnaire in two seasons. Participants provided the blood and urine samples over 3 consecutive days for measuring sex hormones and urinary phthalate metabolites. We assessed the associations of urinary phthalate metabolites levels, lifestyle with hormones levels, the interaction of phthalate exposure and lifestyle with hormones levels using multivariate binary logistic regression models. High urinary mono-(2-ethyl-5-oxyhexyl) phthalate (MEOHP) levels and no exercise had an additive interaction on abnormal serum progesterone (PROG) levels in winter as well as on abnormal serum follicle-stimulating hormone (FSH) or luteinizing hormone (LH) levels in summer. High urinary MEOHP levels and red meat intake (>1 time/day) had an additive interaction with abnormal levels of serum FSH only in the winter. Phthalates exposure may confer differential susceptibility to abnormal hormones levels in individuals with no exercise or eating meat >1 time/day.

Use of dietary supplements in relation to urinary phthalate metabolite concentrations: Results from the National Health and Nutrition Examination Survey

BACKGROUND

Research suggests that dietary supplements may be a source of exposure to phthalates, given that diethyl phthalate (DEP) or di-n-butyl phthalate (DBP) can be components of coatings that facilitate extended release or encapsulate dietary supplements.

METHODS

Using nationally representative data on a population of 12,281 adults ages 20 y + surveyed between 1999 and 2014 from the National Health and Nutrition Examination Survey (NHANES), we evaluated the association between dietary supplement use in relation to urinary phthalate metabolites of DEP (monoethyl phthalate, MEP) and DBP (mono-n-butyl phthalate, MBP). We examined associations pertaining to regular use of multivitamin/multimineral (MVMM) supplements, as well as regular use of any other non-MVMM supplement products, the number of non-MVMM supplement products used, as well as individual supplements potentially containing phthalates (exclusive of MVMM). For each urinary phthalate metabolite, results are presented as the minimally-adjusted and multivariable-adjusted ratio, comparing the geometric mean among users to non-users.

RESULTS

In multivariable models, we observed a significant positive association between regular use of MVMM use and MEP, with persons using MVMM supplements having 11% higher geometric mean MEP than non-users (Ratio: 1.11; 95% CI: 1.04-1.20); no association was observed for MVMM in relation to MBP. No other significant multivariable-adjusted associations were observed, although power was limited in analyses of individual supplements. Associations did not markedly vary by gender; however, the associations of garlic supplement use with MEP and MBP varied by calendar time, with statistically significant positive associations observed in later years.

CONCLUSIONS

A modest significant association was observed between MVMM use and MEP. No other significant associations were observed in our overall multivariable models. Follow-up on the positive association observed between garlic and urinary phthalate metabolite concentrations observed in later years in a well-powered, prospective study would further clarify study findings.

Distribution and Dietary Predictors of Urinary Phthalate Metabolites among Pregnant Women in Shanghai, China

The exposure of pregnant women to phthalates is a major concern due to their adverse effect on developmental outcomes. Diet is an important pathway for exposure to phthalate compounds. Nevertheless, studies on dietary exposure of pregnant women to phthalates in China are limited. We aimed to assess the distribution and dietary predictors of phthalate exposure among pregnant women in China. We measured the levels of 10 urinary phthalate metabolites using high-performance liquid chromatography coupled with tandem mass spectrometry in 210 pregnant women as part of the 2015 China National Chronic Disease and Nutrition Survey in Shanghai. We assessed the urinary specific gravity-adjusted phthalate metabolite levels along with potential demographic and dietary predictors. Multivariable linear regression analysis was used to examine the relationship between each potential demographic variable and dietary predictor and urinary phthalate metabolites. Seven urinary phthalate metabolites were detected in >95% of pregnant women. The geometric mean (GM) of urinary phthalate biomarker values were highest for monobutyl phthalate (GM: 25.29 ng/mL) and monoisobutyl phthalate (GM:11.18 ng/mL). Multivariate regression analysis indicated that a lower educational level was associated with elevated urinary phthalate metabolite levels. Edible seaweed consumption had a positive correlation with urinary monoethyl phthalate and monoisobutyl phthalate levels, and the total molar sum of Di-(2-ethylhexyl) phthalate metabolites. These findings offer important data on the dietary exposure to phthalates in pregnant Chinese women and suggest interventions to improve food safety.

A Review of Biomonitoring of Phthalate Exposures

Phthalates (diesters of phthalic acid) are widely used as plasticizers and additives in many consumer products. Laboratory animal studies have reported the endocrine-disrupting and reproductive effects of phthalates, and human exposure to this class of chemicals is a concern. Several phthalates have been recognized as substances of high concern. Human exposure to phthalates occurs mainly via dietary sources, dermal absorption, and air inhalation. Phthalates are excreted as conjugated monoesters in urine, and some phthalates, such as di-2-ethylhexyl phthalate (DEHP), undergo secondary metabolism, including oxidative transformation, prior to urinary excretion. The occurrence of phthalates and their metabolites in urine, serum, breast milk, and semen has been widely reported. Urine has been the preferred matrix in human biomonitoring studies, and concentrations on the order of several tens to hundreds of nanograms per milliliter have been reported for several phthalate metabolites. Metabolites of diethyl phthalate (DEP), dibutyl- (DBP) and diisobutyl- (DiBP) phthalates, and DEHP were the most abundant compounds measured in urine. Temporal trends in phthalate exposures varied among countries. In the United States (US), DEHP exposure has declined since 2005, whereas DiNP exposure has increased. In China, DEHP exposure has increased since 2000. For many phthalates, exposures in children are higher than those in adults. Human epidemiological studies have shown a significant association between phthalate exposures and adverse reproductive outcomes in women and men, type II diabetes and insulin resistance, overweight/obesity, allergy, and asthma. This review compiles biomonitoring studies of phthalates and exposure doses to assess health risks from phthalate exposures in populations across the globe.