Asthma in inner-city children at 5-11 years of age and prenatal exposure to phthalates: the Columbia Center for Children's Environmental Health Cohort

Phytotoxic impact of di-butyl phthalate (DBP) on physiological, biochemical, and oxidative stress parameters of rice (Oryza sativa)

Phthalates are synthetic compounds, well-known plasticizers, with numerous applications and reported to have adverse effects on all living organisms residing in terrestrial and aquatic environments. In this study, the rice (Oryza sativa) seedlings were exposed to di-butyl phthalate (DBP) exogenously for 7 days, with varying concentrations of 0, 200, 400, 800, and 1600 mg/L, to explore the toxicological, physiological, and biochemical consequences by measuring various parameters such as pigment, lipid, and H2O2 (hydrogen peroxide) contents. The biochemical analysis of seedlings showed that the pigments, lipids, and H2O2 concentrations were altered abnormally. After 7 days of exposure, the maximum amount of DBP was accumulated and translocated in both the shoot and root of the grown seedlings, and all morphological parameters (i.e., length and weight of both shoot and root) and pigment content (such as total carotenoid, chlorophyll a and b) were declined significantly. Superoxide dismutase (SOD), H2O2, and thiobarbituric acid reactive substance (TBARS) levels in seedlings increase as the stress increases due to the higher exposure dose of DBP. Cell viability was observed under a confocal microscope confirming the damage of the plasma membrane. Additionally, molecular docking studies indicated that DBP has a good binding affinity with key antioxidant enzymes of Oryza sativa, interacting via hydrogen bonds with specific amino acids. This suggests a potential mechanistic pathway for the observed biochemical changes in Oryza sativa.

Personal care product use and risk of adult-onset asthma: findings from the Sister Study

BACKGROUND

Personal care products (PCPs) contain endocrine-disrupting chemicals (EDCs) linked to hormonally-sensitive diseases. Population studies have found associations between prenatal EDC exposure and childhood asthma; however, few have investigated adult-onset asthma.

OBJECTIVES

We investigated the associations between commonly used PCPs and the risk of adult-onset asthma in a prospective cohort study of U.S. women.

METHODS

We analyzed 39,408 participants from the Sister Study (2003-2009). The participants self-reported their usage frequency of 41 PCPs in the 12-month period before baseline. Latent classes were used to identify groups with similar usage patterns ('infrequent', 'moderate', 'frequent') within types of products ('beauty', 'everyday hair', 'hygiene', and 'skincare'). Multivariable Cox regression models were used to assess the associations between PCP use and incident adult-onset asthma.

RESULTS

Over an average 12.5-year follow-up, 1,774 incident asthma cases were identified. Compared to infrequent users, moderate (hazard ratio [HR]=1.21 (95% confidence interval (CI):1.07,1.37)) and frequent (HR=1.22 (95%CI:1.08,1.38)) users of beauty products had significantly higher asthma risk. Similar associations were observed for hygiene (moderate: HR=1.14 (95%CI:1.01,1.29) and frequent: HR=1.20 (95%CI:1.06,1.36)) and skincare products (moderate: HR=1.21 (95%CI:1.06,1.38) and frequent: HR=1.20 (95%CI:1.06,1.35)). Several individual everyday hair products (hair spray, hair styling gel/mousse, and pomade or hair grease) were positively associated with asthma risk, but associations were not detected for everyday hair latent classes.

DISCUSSION

Our findings suggest that PCP use potentially contributes to future risk of adult-onset asthma among women. These novel findings reinforce the need for regulation of PCPs and their components to reduce the burden of asthma.

Associations of environmental chemical exposures measured in personal silicone wristbands with sociodemographic factors, COVID-19 restrictions, and child respiratory health

BACKGROUND

Although human biomonitoring of environmental chemicals has been considered a gold standard, these methods can be costly, burdensome, and prone to unwanted sources of variability that may cause confounding. Silicone wristbands have recently emerged as innovative passive samplers for measuring personal exposures.

METHODS

In a pilot study from 2019 to 2021 involving 55 children aged 5-9 years in Seattle and Yakima, Washington, we utilized silicone wristbands to explore associations of sociodemographic variables and COVID-19-related restrictions, including school closures, with exposures to numerous chemicals including brominated and organophosphate ester (OPE) flame retardants, polychlorinated biphenyls, polycyclic aromatic hydrocarbons (PAHs), phthalates, and pesticides. We additionally conducted the first analysis testing silicone wristband chemicals as predictors of child wheeze, individually and in mixtures via logistic weighted quantile sum regression (WQS).

RESULTS

Among 109 semi-volatile organic compounds measured, we detected 40 in >60% of wristbands worn by children continuously for an average of 5 days. Chemicals were generally positively correlated, especially within the same class. Male sex and increasing age were linked with higher exposures across several chemical classes; Hispanic/Latino ethnicity was linked with higher exposures to some phthalates and OPEs. COVID-19 restrictions were associated with lower wristband concentrations of brominated and triaryl OPE flame retardants. Each one-decile higher WQS exposure index was suggestively associated with 2.11-fold [95% CI: 0.93-4.80] higher odds of child wheeze. Risk of child wheeze was higher per 10-fold increase in the PAH chrysene (RR = 1.93[1.07-3.49]), the pesticide cis-permethrin (3.31[1.23-8.91]), and di-isononyl phthalate (DINP) (5.40[1.22-24.0]) CONCLUSIONS: Our identification of demographic factors including sex, age, and ethnicity associated with chemical exposures may aid efforts to mitigate exposure disparities. Lower exposures to flame retardants during pandemic restrictions corroborates prior evidence of higher levels of these chemicals in school versus home environments. Future research in larger cohorts is needed to validate these findings.

Glycolysis mediates the association between phthalate exposure and the prevalence of childhood asthma: The National Health and Nutrition Examination Survey 2009-2018

Identified as a critical risk factor for childhood asthma, environmental pollution plays a pivotal role. However, research on the effects and mechanisms of phthalates mixture and their interactions in relation to childhood asthma is still lacking. In the National Health and Nutrition Examination Survey (NHANES) conducted from 2009 to 2018, our research explored the link between phthalates in urine and the prevalence of childhood asthma. In this study, which involved 810 participants, we used four different statistical analysis methods to investigate the association between urinary phthalate levels and childhood asthma. Additionally, we conducted a mediation analysis to explore whether the impact mechanism of phthalate exposure on childhood asthma operates through the glycolysis. Among the participants, 525 (64.81 %) individuals were diagnosed with asthma, with 330 (40.74 %) individuals undergoing testing for glycolytic markers. Through Spearman correlation analysis and weighted principal component analysis (W-PCA), it was found that mono-2-ethyl-5-carboxypentyl phthalate (MECPP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono-(2-ethyl)-hexyl phthalate (MEHP) and mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP) are the four most highly correlated phthalates. In addition, comprehensive analysis by the weighted generalized linear models (W-GLM), weighted quantile sum (WQS) and Bayesian kernel machine regression (BKMR) models showed that phthalates mixture were positively associated with the prevalence of childhood asthma, especially MECPP, MEHHP and MEOHP. More importantly, glycolysis participated as a mediator in the relationship between MECPP, MEHHP and MEOHP exposure and the prevalence of childhood asthma, explaining 41.194 %, 38.322 % and 39.871 % of the effects respectively. Therefore, our study revealed that phthalate exposure is a risk factor for asthma in children, and glycolysis may be involved as a potential mediator in this process. This conclusion will be verified through more prospective studies in the future.

Urinary biomarkers of environmental exposures and asthma morbidity in a school inner city asthma study

BACKGROUND

The burden of pediatric asthma and other allergic diseases is not evenly distributed among United States populations.

OBJECTIVE

To determine whether urinary biomarkers are associated with asthma morbidity, and if associations vary by child race, ethnicity and sex.

METHODS

This study includes n = 152 children with physician-diagnosed asthma who participated in the School Inner-City Asthma Intervention Study (SICAS-2). Metabolites of phenol, paraben, polycyclic aromatic hydrocarbons, and phthalate analytes were analyzed from urine samples collected at baseline. Asthma symptom days over the past 2 weeks were dichotomized to no asthma symptom days or any asthma symptom days. Cross-sectional regression models were adjusted for age, sex, number of colds, household income, prescription control, race and ethnicity, body mass index (BMI) percentile, and smoke exposure. Weighted quantile sum regression was used to analyze each chemical class and a total mixture effect, controlling for the same covariates. Analyses were conducted with the assistance of the National Institute of Environmental Health Sciences Children's Health Exposure Analysis Resource (CHEAR).

RESULTS

Participants were mostly Hispanic/Latino and low income with an average age of 7.83 years and the average maximum asthma symptom days over the past two weeks of 2.13 (standard deviation: 3.56). The maximum concentrations indicate extreme values for several chemicals, including bisphenol-3, 2,5-dichlorophenol, propyl and methyl parabens, triclosan, methyl paraben and cotinine. We found a significant interaction effect and differing contributions of analytes for children with allergen sensitivity versus those that did not. For stratified analyses assessing effect modification by child race and ethnicity, weighted quantile sum interaction models showed reduced odds of asthma symptoms to a greater magnitude in children of other races and ethnicities compared to Black, Non-Hispanic children.

CONCLUSIONS

Preliminary analyses of the association between environmental chemical exposure and asthma symptoms among inner-city children revealed an inverse association, which may be due to personal care and medication use and can be understood further in future analyses. Beneficial effects were detected for most of the chemicals.

Associations of prenatal exposure to phthalates and their mixture with lung function in Mexican children

Early life phthalates exposure has been associated with adverse respiratory outcomes. However, evidence linking prenatal phthalates exposure and childhood lung function has been inconclusive. Additionally, few studies have examined phthalates exposure as a mixture and explored sexually dimorphic associations. We aimed to investigate sex-specific associations of prenatal phthalates mixtures with childhood lung function using the PROGRESS cohort in Mexico (N = 476). Prenatal phthalate concentrations were measured in maternal urine collected during the 2nd and 3rd trimesters. Children's lung function was evaluated at ages 8-13 years. Individual associations were assessed using multivariable linear regression, and mixture associations were modeled using repeated holdout WQS regression and hierarchical BKMR; data was stratified by sex to explore sex-specific associations. We identified significant interactions between 2nd trimester phthalates mixture and sex on FEV1 and FVC z-scores. Higher 2nd trimester phthalate concentrations were associated with higher FEV1 (β = 0.054, 95 %CI: 0.005, 0.104) and FVC z-scores (β = 0.074, 95 % CI: 0.024, 0.124) in females and with lower measures in males (FEV1, β = -0.017, 95 %CI: -0.066, 0.026; FVC, β = -0.014, 95 %CI: -0.065, 0.030). This study indicates that prenatal exposure to phthalates is related to childhood lung function in a sex-specific manner.

Association Between Urinary Phthalate Metabolites and Chronic Obstructive Pulmonary Disease: A Cross-Sectional Study

Objective

To determine the association of urinary phthalate metabolites with chronic obstructive pulmonary disease (COPD), airflow obstruction, lung function and respiratory symptoms.

Methods

Our study included a total of 2023 individuals aged ≥ 40 years old in the National Health and Nutrition Examination Survey (NHANES). Multivariate logistic regression was conducted to explore the correlation of eleven urinary phthalate metabolites (MCNP, MCOP, MECPP, MnBP, MCPP, MEP, MEHHP, MEHP, MiBP, MEOHP, and MBzP) with COPD, airflow obstruction and respiratory symptoms. Linear regression analyses were used to evaluate the relationship between urinary phthalate metabolites and lung function.

Results

When compared to the first tertile, the third tertile of MEHHP was associated with the risk of COPD [OR: 2.779; 95% confidence interval (CI): 1.129-6.840; P = 0.026]. Stratified analysis showed that MEHHP increased the risk of COPD by 7.080 times in male participants. Both MCPP and MBzP were positively correlated with the risk of airflow obstruction. The third tertile of MBzP increased the risk of cough by 1.545 (95% CI: 1.030-2.317; P = 0.035) times. Both FEV1 and FVC were negatively associated with MEHHP, MECPP, MnBP, MEP, MiBP and MEOHP.

Conclusion

Higher levels of MEHHP are associated with increased risk of COPD, and lower measures of FEV1 and FVC. MBzP is positively related to airflow obstruction and cough.

Recent Insights into the Environmental Determinants of Childhood Asthma

PURPOSE OF REVIEW

Ubiquitous environmental exposures, including ambient air pollutants, are linked to the development and severity of childhood asthma. Advances in our understanding of these links have increasingly led to clinical interventions to reduce asthma morbidity.

RECENT FINDINGS

We review recent work untangling the complex relationship between air pollutants, including particulate matter, nitrogen dioxide, and ozone and asthma, such as vulnerable windows of pediatric exposure and their interaction with other factors influencing asthma development and severity. These have led to interventions to reduce air pollutant levels in children's homes and schools. We also highlight emerging environmental exposures increasingly associated with childhood asthma. Growing evidence supports the present threat of climate change to children with asthma. Environmental factors play a large role in the pathogenesis and persistence of pediatric asthma; in turn, this poses an opportunity to intervene to change the course of disease early in life.

Phthalate exposure and lung disease: the epidemiological evidences, plausible mechanism and advocacy of interventions

Phthalates are a kind of synthetic plasticizers, which extensively used as plastic productions to improve their plasticity and flexibility. However, exposure to phthalates has been proved an increased risk of respiratory disease, because by they affect the development and functions of the lung and immune system. Here, we attempt to review respiratory health of phthalate exposure. Firstly, we describe the relationship between phthalates and lung function and airway inflammation. Then, the role of phthalates in asthma, lung cancer, rhinitis, and respiratory tract infections and the possible mechanisms of action are discussed. Finally, possible effective measures to reduce exposure to phthalates are proposed, and health care workers are called upon to provide educational resources and advocate for informed public health policies. Overall, the evidence for association between phthalate exposure and respiratory disease is weak and inconsistent. Therefore, thorough implementation in large populations is needed to produce more consistent and robust results and to enhance the overall understanding of the potential respiratory health risks of phthalate in long-term exposure.

Mycotoxins from Alternaria Panax, the specific plant pathogen of Panax ginseng

Ginseng black spot, caused by Alternaria panax, is one of the most common diseases of Panax ginseng, which usually causes serious yield loss of ginseng plants. However, the pathogenic mechanism of A. panax has not been clarified clearly. Mycotoxins produced by phytopathogens play an important role in the process of infection. Previous study reported that dibutyl phthalate (DBP) identified from the metabolites of A. panax is a potent mycotoxin against P. ginseng. However, more evidence suggests that DBP is one of the constituents of plasticisers. To identify mycotoxins from A. panax and evaluate their phytotoxicity on the leaves of P. ginseng, different chromatographic, spectral and bioassay-guided methods were used together in this report. As a result, tyrosol (1), 3-hydroxy-3-(4-methoxyphenyl) propanoic acid (2), and 3-benzylpiperazine-2,5-dione (3) were isolated and characterised from the extract of A. panax, in which compounds 1 and 2 showed phytotoxic activity on ginseng leaves. Furthermore, DBP was confirmed to come from the residue of ethyl acetate through UPLC-MS/MS analysis, and displayed no phytotoxicity on ginseng leaves based on biological experiments. The results in this report first revealed that tyrosol (1), and 3-hydroxy-3-(4-methoxyphenyl) propanoic acid (2) not DBP were the potent mycotoxins of A. panax.

Pre- and postnatal maternal hair dye use and risk of wheeze and asthma in 5-year-old Japanese children: the Kyushu Okinawa Maternal and Child Health Study

The present study investigated the association between pre- and postnatal maternal hair dye use and the risk of wheeze and asthma in Japanese children aged 5 years. Study participants were 1199 mother-child pairs. Information on the variables under study was obtained using repeated questionnaires completed by parents. Prenatal maternal hair dye use was associated with an increased risk of current wheeze and ever doctor-diagnosed asthma; the adjusted odds ratios (ORs) (95% confidence intervals [CIs]) were 1.44 (1.02-2.02) and 1.51 (1.00-2.25), respectively. Postnatal maternal hair dye use was related to the risk of doctor-diagnosed asthma; the adjusted OR (95% CI) was 1.58 (1.03-2.40). Children who were exposed to maternal hair dye use both prenatally and postnatally had an increased risk of childhood current wheeze and ever doctor-diagnosed asthma; the adjusted ORs (95% CIs) were 1.59 (1.03-2.42) and 1.76 (1.06-2.88), respectively. Our findings suggest that perinatal maternal hair dye use is associated with the risk of wheeze and asthma in children.

Phthalate exposure in the neonatal intensive care unit is associated with development of bronchopulmonary dysplasia

OBJECTIVE

Bronchopulmonary dysplasia (BPD) is a serious yet common morbidity of preterm birth. Although prior work suggests a possible role for phthalate exposure in the development of BPD, no study has rigorously evaluated this. Our objective was to determine whether hospital-based phthalate exposure is associated with the development of BPD and to identify developmental windows sensitive to exposure.

STUDY DESIGN

This is a prospective multicenter cohort study of 360 preterm infants born at 23-33 weeks gestation participating in the Developmental Impact of NICU Exposures (DINE) cohort. 939 urine specimens collected during the NICU stay were analyzed for biomarkers of phthalate exposure by liquid chromatography with tandem mass spectrometry. The modified Shennan definition was used to diagnose bronchopulmonary dysplasia. Reverse distributed-lag modeling identified developmental windows sensitive to specific phthalate exposure, controlling for relevant covariates including sex and respiratory support.

RESULTS

Thirty-five percent of participants were diagnosed with BPD. Exposure to specific phthalate mixtures at susceptible points in preterm infant development are associated with later diagnosis of BPD in models adjusted for use of respiratory support. The weighted influence of specific phthalate metabolites in the mixtures varied by sex. Metabolites of di(2-ethylhexyl) phthalate, a phthalate previously linked to neonatal respiratory support equipment, drove this association, particularly among female infants, at 26- to 30-weeks post-menstrual age.

CONCLUSIONS

This is the largest and only multi-site study of NICU-based phthalate exposure and clinical impact yet reported. In well-constructed models accounting for infant sex and respiratory support, we found a significant positive association between ultimate diagnosis of BPD and prior exposure to phthalate mixtures with DEHP predominance at 26- to 30-weeks PMA or 34-36-weeks PMA. This information is critically important as it identifies a previously unrecognized and modifiable contributing factor to BPD.

A cross sectional pilot study to assess the role of phthalates on respiratory morbidity among patients with chronic obstructive pulmonary disease

BACKGROUND

Chronic Obstructive Pulmonary Disease (COPD) affects ∼16 million U.S. adults. Phthalates, synthetic chemicals in consumer products, may adversely impact pulmonary function and airway inflammation; however, their role on COPD morbidity remains unknown.

OBJECTIVE

We examined associations between phthalate exposures and respiratory morbidity among 40 COPD patients who were former smokers.

METHODS

We quantified 11 phthalate biomarkers in urine samples collected at baseline in a 9-month prospective cohort study in Baltimore, Maryland. COPD baseline morbidity measures included: health status and quality of life measures (CAT: COPD Assessment Test, CCQ: Clinical COPD Questionnaire, SGRQ: St. George's Respiratory Questionnaire; mMRC: Modified Medical Research Council Dyspnea Scale), and lung function. Information on prospective exacerbation data was monitored monthly during the 9-month longitudinal follow-up period. To examine associations between morbidity measures and phthalate exposures, we used multivariable linear and Poisson regression models for continuous and count outcomes, respectively, adjusting for age, sex, race/ethnicity, education, and smoking pack-years.

RESULTS

Higher mono-n-butyl phthalate (MBP) concentrations were associated with increased CAT(β, 2.41; 95%CI, 0.31-4.51), mMRC (β, 0.33; 95%CI 0.11-0.55), and SGRQ (β, 7.43; 95%CI 2.70-12.2) scores at baseline. Monobenzyl phthalate (MBzP) was also positively associated with CCQ and SGRQ scores at baseline. Higher concentrations of the molar sum of Di (2-ethylhexyl) phthalate (DEHP) were associated with increased incidence of exacerbations during the follow-up period (incidence rate ratio, IRR = 1.73; 95%CI 1.11, 2.70 and IRR = 1.94; 95%CI 1.22, 3.07, for moderate and severe exacerbations, respectively). MEP concentrations were inversely associated with incidence of exacerbations during the follow-up period.

CONCLUSIONS

We found that exposure to select phthalates was associated with respiratory morbidity among COPD patients. Findings warrant further examination in larger studies given widespread phthalate exposures and potential implications for COPD patients should relationships observed be causal.

Prenatal exposure to synthetic phenols and phthalates and child respiratory health from 2 to 36 months of life

Exposure to phthalates and synthetic phenols is ubiquitous. Some of them are suspected to impact child respiratory health, although evidence still remains insufficient. This study investigated the associations between prenatal exposure to phthalates and phenols, individually and as a mixture, and child respiratory health assessed by objective lung function measures since 2 months of age. Among 479 mother-child pairs from the SEPAGES cohort, 12 phenols, 13 phthalate and 2 non-phthalate plasticizer metabolites were measured in 2 pools including each 21 urine samples collected at the 2nd and 3rd pregnancy trimesters. Lung function was measured at 2 months using tidal breathing flow-volume loops and nitrogen multiple-breath washout, and at 3 years using oscillometry. Asthma, wheezing, bronchitis and bronchiolitis were assessed by repeated questionnaires. A cluster-based analysis was applied to identify exposure patterns to phenols and phthalates. Adjusted associations between clusters as well as each individual exposure biomarker and child respiratory health were estimated by regression models. We identified four prenatal exposure patterns: 1) low concentrations of all biomarkers (reference, n = 106), 2) low phenols-moderate phthalates (n = 162), 3) high concentrations of all biomarkers except bisphenol S (n = 109), 4) high parabens-moderate other phenols-low phthalates (n = 102). At 2 months, cluster 2 infants had lower functional residual capacity and tidal volume and higher ratio of time to peak tidal expiratory flow to expiratory time (t_PTEF/t_E) and cluster 3 had lower lung clearance index and higher t_PTEF/t_E. Clusters were not associated with respiratory health at 3 years but in the single-pollutant models, parabens were associated with increased area of the reactance curve, bronchitis (methyl, ethyl parabens) and bronchiolitis (propyl paraben). Our results suggested that prenatal exposure to mixtures of phthalates reduced lung volume in early life. Single exposure analyses suggested associations of parabens with impaired lung function and increased risk of respiratory diseases.

A study on the association of placental and maternal urinary phthalate metabolites

BACKGROUND

Phthalate exposure in pregnancy is typically estimated using maternal urinary phthalate metabolite levels. Our aim was to evaluate the association of urinary and placental tissue phthalates, and to explore the role of maternal and pregnancy characteristics that may bias estimates.

METHODS

Fifty pregnancies were selected from the CANDLE Study, recruited from 2006 to 2011 in Tennessee. Linear models were used to estimate associations of urinary phthalates (2nd, 3rd trimesters) and placental tissue phthalates (birth). Potential confounders and modifiers were evaluated in categories: temporality (time between urine and placenta sample), fetal sex, demographics, social advantage, reproductive history, medication use, nutrition and adiposity. Molar and quantile normalized phthalates were calculated to facilitate comparison of placental and urinary levels.

RESULTS

Metabolites detectable in >80% of both urine and placental samples were MEP, MnBP, MBzP, MECPP, MEOHP, MEHHP, and MEHP. MEP was most abundant in urine (geometric mean [GM] 7.00 ×102 nmol/l) and in placental tissue (GM 2.56 ×104 nmol/l). MEHP was the least abundant in urine (GM 5.32 ×101 nmol/l) and second most abundant in placental tissue (2.04 ×104 nmol/l). In aggregate, MEHP differed the most between urine and placenta (2.21 log units), and MEHHP differed the least (0.07 log units). MECPP was positively associated between urine and placenta (regression coefficient: 0.31 95% CI 0.09, 0.53). Other urine-placenta metabolite associations were modified by measures of social advantage, reproductive history, medication use, and adiposity.

CONCLUSION

Phthalates were ubiquitous in 50 full-term placental samples, as has already been shown in maternal urine. MEP and MEHP were the most abundant. Measurement and comparison of urinary and placental phthalates can advance knowledge on phthalate toxicity in pregnancy and provide insight into the validity and accuracy of relying on maternal urinary concentrations to estimate placental exposures.

IMPACT STATEMENT

This is the first report of correlations/associations of urinary and placental tissue phthalates in human pregnancy. Epidemiologists have relied exclusively on maternal urinary phthalate metabolite concentrations to assess exposures in pregnant women and risk to their fetuses. Even though it has not yet been confirmed empirically, it is widely assumed that urinary concentrations are strongly and positively correlated with placental and fetal levels. Our data suggest that may not be the case, and these associations may vary by phthalate metabolite and associations may be modified by measures of social advantage, reproductive history, medication use, and adiposity.

Environmental Health Knowledge Does Not Necessarily Translate to Action in Youth

Environmental challenges pose serious health problems, especially for children, and lay public action is lacking. This study sought to characterize the relationship between environmental health knowledge and behavior in youth. A cross-sectional, descriptive survey with quantitative and qualitative questions was conducted. Open-ended questions were coded to generate themes/subthemes. Subscales' scores were presented as mean ± SD or median and interquartile range (IQR). T- and Mann-Whitney tests were used to compare groups, and correlations were used to evaluate covariation. A total of 452 children were surveyed. Youth verbalized concerns about their environments and their impact on health. Air pollution was the most concerning issue. Participants had moderate knowledge scores. Few described the three health domains; even fewer included environment. Behavior scores were low and weakly correlated with knowledge, but were moderately correlated with attitude and self-efficacy. Participation in environmental classes, activities, and clubs was associated with higher scores. We found variable environmental health knowledge, limited understanding of the local environment's impact on health, and a weak association between youth's knowledge and behavior. Focused formal and non-formal educational experiences were associated with improved scores, indicating the value of targeted youth educational programming to increase environmental health knowledge and action.

Gestational phthalate exposure and lung function during childhood: A prospective population-based study

The potential effect of gestational exposure to phthalates on the lung function levels during childhood is unclear. Therefore, we examined this association at different ages (from 4 to 11 years) and over the whole childhood. Specifically, we measured 9 phthalate metabolites (MEP, MiBP, MnBP, MCMHP, MBzP, MEHHP, MEOHP, MECPP, MEHP) in the urine of 641 gestating women from the INMA study (Spain) and the forced vital capacity (FVC), forced expiratory volume in 1 s (FEV₁) and FEV₁/FVC in their offspring at ages 4, 7, 9 and 11. We used linear regression and mixed linear regression with a random intercept for subject to assess the association between phthalates and lung function at each study visit and for the overall childhood, respectively. We also assessed the phthalate metabolites mixture effect on lung function using a Weighted Quantile Sum (WQS) regression. We observed that the phthalate metabolites gestational levels were consistently associated with lower FVC and FEV₁ at all ages, both when assessed individually and jointly as a mixture, although most associations were not statistically significant. Of note, a 10% increase in MiBP was related to lower FVC (-0.02 (-0.04, 0)) and FEV₁ z-scores (-0.02 (-0.04, -0.01) at age 4. Similar significant reductions in FVC were observed at ages 4 and 7 associated with an increase in MEP and MnBP, respectively, and for FEV₁ at age 4 associated with an increase in MBzP. WQS regression consistently identified MBzP as an important contributor to the phthalate mixture effect. We can conclude that the gestational exposure to phthalates was associated with children's lower FVC and FEV₁, especially in early childhood, and in a statistically significant manner for MEP, MiBP, MBzP and MnBP. Given the ubiquity of phthalate exposure and its established endocrine disrupting effects in children, our findings support current regulations that limit phthalate exposure.

Phthalate Metabolites in Urine of Chinese Children and Their Association with Asthma and Allergic Symptoms

Phthalates are ubiquitous 'modern' chemical compounds with potential negative impacts on children's health. A nested case-control study was designed to investigate associations of phthalate exposure with children's asthma and allergic symptoms. We collected 243 first morning urine samples from 4-8-year-old children in Tianjin, China. Eight metabolites (i.e., mono-ethyl phthalate (MEP), mono-isobutyl phthalate (MiBP), mono-n-butyl phthalate (MnBP), mono-benzyl phthalate (MBzP) and mono-2-ethylhexyl phthalate (MEHP), mono-(2-ethyl-5-carboxylpentyl) phthalate (MECPP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP)) of five phthalates were analyzed using HPLC-MS. MiBP, MnBP and MECPP were the dominant phthalate metabolites in urine of children in Tianjin with median concentrations of 31.6 μg/L, 26.24 μg/L and 46.12 μg/L, respectively. We found significantly positive associations of diagnosed asthma with MnBP (adjusted odds ratios (AOR): 1.96; 95% confidence intervals (CIs): 1.07-3.61), MEHHP (AOR: 2.00; 95% CI: 1.08-3.71) and MEOHP (AOR: 2.09; 95% CI: 1.06-4.10). Our study indicates that phthalate exposure in childhood, especially to di-n-butyl phthalate (DnBP) and di(2-ethylhexyl) phthalate (DEHP), may be a risk factor for children's asthma.

National-scale urinary phthalate metabolites in the general urban residents involving 26 provincial capital cities in China and the influencing factors as well as non-carcinogenic risks

Phthalates (PAEs) are widely used in daily products but can cause a variety of adverse effects in humans. Few studies have been carried out on human internal exposure levels of PAEs on a large-scale, especially in developing countries. In the present study, 1161 urine samples collected from residents of 26 provincial capitals in China were analyzed for nine phthalate metabolites (mPAEs). The chemicals were widely detected, and the median specific gravity adjusted urinary concentration of Σ₉mPAEs was 278 μg/L. Di-(2-ethylhexyl) phthalate (DEHP) and di-n-butyl phthalate (DnBP) were the main parent PAEs that the residents were exposed to. Demographic characteristics, such as age and educational level, were significantly associated with PAE exposure. Children and the elderly had higher mPAE levels. Subjects with lower educational levels were more frequently exposed to DnBP and DEHP. However, mono-ethyl phthalate showed the opposite trend, i.e., higher concentrations in subjects aged 18-59 years and with higher educational levels. Geographic differences were detected at the national scale. Residents in northeastern and western China had higher levels of mPAEs than those in central China, most likely because of different industrial usage of the chemicals and different living habits and living conditions of the residents. Health risk assessment showed that hazard indices of PAEs ranged from 0.07 to 9.34, with 20.0% of the subjects being concern for potential non-carcinogenic risk as assessed by Monte Carlo simulation. DEHP and DnBP were the primary contributors, representing 96.7% of total risk. This first large-scale study on PAE human internal exposure in China provides useful information on residents' health in a developing country, which could be used for chemical management and health protection.

Phthalate Exposures and Placental Health in Animal Models and Humans: A Systematic Review

Phthalates are ubiquitous compounds known to leach from the plastic products that contain them. Due to their endocrine-disrupting properties, a wide range of studies have elucidated their effects on reproduction, metabolism, neurodevelopment, and growth. Additionally, their impacts during pregnancy and on the developing fetus have been extensively studied. Most recently, there has been interest in the impacts of phthalates on the placenta, a transient major endocrine organ critical to maintenance of the uterine environment and fetal development. Phthalate-induced changes in placental structure and function may have significant impacts on the course of pregnancy and ultimately, child health. Prior reviews have described the literature on phthalates and placental health; however to date, there has been no comprehensive, systematic review on this topic. Here, we review 35 papers (24 human and 11 animal studies) and summarize phthalate exposures in relation to an extensive set of placental measures. Phthalate-related alterations were reported for placental morphology, hormone production, vascularization, histopathology, and gene/protein expression. The most consistent changes were observed in vascular and morphologic endpoints, including cell composition. These changes have implications for pregnancy complications such as preterm birth and intrauterine growth restriction as well as potential ramifications for children's health. This comprehensive review of the literature, including common sources of bias, will inform the future work in this rapidly expanding field.

Are Phthalate Exposure Related to Oxidative Stress in Children and Adolescents with Asthma? A Cumulative Risk Assessment Approach

Childhood asthma has become one of the most common chronic diseases in children and adolescents. However, few case–control studies investigating the relationship between phthalate exposure and asthma in children and adolescents have been conducted, especially in Asia. Therefore, we assessed the potential associations between phthalate exposure and asthma among children and adolescents in Taiwan. Because various demographic and environmental variables may influence the incidence and prognosis of asthma, we performed a case–control study with propensity score matching. Out of 615 Childhood Environment and Allergic Diseases Study participants, we conditionally matched 41 children with clinically diagnosed asthma with 111 controls. We then analyzed 11 phthalate metabolites by using liquid chromatography with tandem mass spectrometry. Compared with the control group, the median urinary phthalate levels for most phthalate metabolites in the case group were slightly increased, including monomethyl phthalate, mono-n-butyl phthalate, monobenzyl phthalate, monoethylhexyl phthalate, mono-(2-ethyl-5-hydroxyhexyl) phthalate, mono-(2-ethyl-5-oxohexyl) phthalate, mono-(2-ethyl-5-carboxypentyl) phthalate, and mono-(2-carboxymethylhexyl) phthalate. Hence, our results suggest that phthalate exposure may be associated with the development of asthma. In addition, prenatal environmental factors, such as active or passive smoking during pregnancy, may increase the risk of asthma.

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

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

A permutation-based approach to inference for weighted sum regression with correlated chemical mixtures

There is a growing demand for methods to determine the effects that chemical mixtures have on human health. One statistical challenge is identifying true "bad actors" from a mixture of highly correlated predictors, a setting in which standard approaches such as linear regression become highly variable. Weighted Quantile Sum regression has been proposed to address this problem, through a two-step process where mixture component weights are estimated using bootstrap aggregation in a training dataset and inference on the overall mixture effect occurs in a held-out test set. Weighted Quantile Sum regression is popular in applied papers, but the reliance on data splitting is suboptimal, and analysts who use the same data for both steps risk inflating the Type I error rate. We therefore propose a modification of Weighted Quantile Sum regression that uses a permutation test for inference, which allows for weight estimation using the entire dataset and preserves Type I error. To minimize computational burden, we propose replacing the bootstrap with L1 or L2 penalization and describe how to choose the appropriate penalty given expert knowledge about a mixture of interest. We apply our method to a national pregnancy cohort study of prenatal phthalate exposure and child health outcomes.

Prenatal phthalate exposure and early childhood wheeze in the SELMA study

BACKGROUND

Prenatal maternal phthalate exposure has been associated with wheeze and asthma in children, but results are inconclusive. Previous studies typically assessed exposure in late pregnancy, included only a small number of old phthalates, and assessed outcomes in children aged 5 years or older.

OBJECTIVE

We explored associations between 1st trimester prenatal maternal exposure to a wider range of phthalates and wheeze in early childhood.

METHODS

First trimester concentrations of 14 metabolites from 8 phthalates and one alternative plasticizer were quantified in first-morning void urine from 1148 mothers in the Swedish SELMA study. Associations between log-transformed metabolite concentrations and parental reported ever wheeze among 24-month-old children were investigated with logistic regression models adjusted for parental asthma/rhinitis, sex of child, maternal education, smoking, and creatinine.

RESULTS

Metabolites of replacement phthalates di-iso-decyl phthalate (DiDP) and di-2-propylheptyl phthalate (DPHP) were associated with increased risk for wheeze (aOR 1.47, 95% CI 1.08-2.01 and aOR 1.49, 95% CI 1.04-2.15, respectively). The associations with DiDP and DPHP were stronger among children whose parents did not have asthma or rhinitis. In this group, wheeze was also associated with metabolites of butyl-benzyl phthalate (BBzP) and di-iso-nonyl phthalate (DiNP).

SIGNIFICANCE

Maternal phthalate exposure during early pregnancy may be a risk factor for wheeze in early childhood, especially among children whose parents do not have asthma or rhinitis symptoms.

Cardiorespiratory responses in healthy young adults with exposure to indoor airborne PAEs: A randomized, crossover trial of air purification

BACKGROUND

Phthalic acid esters (PAEs) are widely used as plasticizers in industrial process and consumer products. Nowadays, PAEs are ubiquitous in the environment and are reported to be associated with cardiorespiratory diseases. However, studies about the association between indoor airborne PAEs exposure and cardiorespiratory health were limited, and the potential biological mechanism remains under-recognized.

METHODS

A randomized crossover trial was conducted on 57 healthy young adults in Beijing. Repeated health measurements were performed under real and sham indoor air purification with a washout interval of at least 2 weeks. The concentration of indoor airborne PAEs were determined by gas chromatography-orbit ion trap mass spectrometry. Health indicators including blood pressure, lung function, airway inflammation, and circulating biomarkers reflecting blood coagulation and systematic oxidative stress were measured. Linear mixed-effect model was used to examine the between-treatment differences in health indicators, and three models including single-constituent, constituent-fine particulate matter (PM_2.5) joint, and single-constituent residual model were used to estimate the association between indoor airborne PAEs and health indicators.

RESULTS

The indoor airborne PAEs were reduced effectively under real air purification. The total indoor airborne di-2-ethylhexyl phthalate (DEHP), bis (4-Methyl-2-pentyl) phthalate (DMPP), diphenyl phthalate (DPP), and diethyl phthalate (DEP) were identified to be most significantly associated with the increase of blood pressure and airway inflammation, and decrease of lung function. A doubling increase in DEHP, DMPP, DPP, DEP was associated with the increase of 17.2% (95% CI: 3.9%, 32.2%), 11.7% (95% CI: 3.5%, 20.6%), 7.0% (95% CI: 2.4%, 11.8%), 6.0% (95% CI: 1.8%, 10.4%) in FeNO, respectively, in single-constituent residual model. Significant associations between specific total indoor airborne PAEs and increased levels of health biomarkers including oxidized low-density lipoprotein (ox-LDL), 8-isoprostane (8-isoPGF2α), and soluble P-selectin (sP-selectin) were observed.

CONCLUSION

Indoor airborne PAEs may cause adverse cardiorespiratory health effects in young healthy adults, and indoor air purification could ameliorate the adverse cardiorespiratory effects.

The association between maternal urinary phthalate metabolites concentrations and pregnancy induced hypertension: Results from the EDEN Mother-Child Cohort

BACKGROUND

Studies have suggested that exposure to endocrine disruptors such as phthalates that are widely used in our daily life (food wrapping, cosmetics, toys, medical devices, polyvinyl chloride flooring, and building materials) might be related to raised blood pressure and increased risk of cardiovascular diseases. Phthalates might induce a pro-inflammatory response and increased oxidative stress and may be a cause of pregnancy induced hypertension.

METHODS

We evaluated the association between maternal exposure to phthalates during pregnancy and pregnancy induced hypertension. 604 pregnant women were included and eleven phthalate metabolites were quantified in spot maternal urine samples collected between the 23rd and 28th week of gestation in a French EDEN mother-child cohort. The associations were assessed by applying multiple logistic regression analysis.

RESULTS

Twenty nine (4,8%) mothers developed pregnancy induced hypertension. Two low molecular weight phthalate metabolites: Monoethyl phthalate (MEP) and Mono-n‑butyl phthalate (MBP) were positively associated with pregnancy induced hypertension in crude (Odds Ratio: 1.43, 95% Confidence Interval: 1.04-1.96, p-value = 0.02 and 1.48, 1.10-2.01, p-value =0.01) and in adjusted (1.47, 1.01-2.14, p-value = 0.04 and 1.66, 1.11-2.47, p-value = 0.01) models respectively.

CONCLUSION

Our data suggest that prenatal exposure to some phthalates, including MEP and MBP, might play a role in pregnancy induced hypertension.

Effect of prenatal exposure to phthalates on epigenome-wide DNA methylations in cord blood and implications for fetal growth: The Hokkaido Study on Environment and Children's Health

Prenatal exposure to phthalates negatively affects the offspring's health. In particular, epigenetic alterations, such as DNA methylation, may connect phthalate exposure with health outcomes. Here, we evaluated the association of di-2-ethylhexyl phthalate (DEHP) exposure in utero with cord blood epigenome-wide DNA methylation in 203 mother-child pairs enrolled in the Hokkaido Study on Environment and Children's Health, using the Illumina HumanMethylation450 BeadChip. Epigenome-wide association analysis demonstrated the predominant positive associations between the levels of the primary metabolite of DEHP, mono(2-ethylhexyl) phthalate (MEHP), in maternal blood and DNA methylation levels in cord blood. The genes annotated to the CpGs positively associated with MEHP levels were enriched for pathways related to metabolism, the endocrine system, and signal transduction. Among them, methylation levels of CpGs involved in metabolism were inversely associated with the offspring's ponderal index (PI). Further, clustering and mediation analyses suggested that multiple increased methylation changes may jointly mediate the association of DEHP exposure in utero with the offspring's PI at birth. Although further studies are required to assess the impact of these changes, this study suggests that differential DNA methylation may link phthalate exposure in utero to fetal growth and further imply that DNA methylation has predictive value for the offspring's obesity.

Operational definitions of paediatric asthma used in epidemiological studies: A systematic review

Background

Researchers use different definitions to identify children with asthma in epidemiological surveys. We conducted a systematic review to describe the definitions used in epidemiologic studies for wheeze and asthma in the paediatric population, aimed to inform the development of a uniform definition of paediatric asthma for future epidemiological research.

Methods

We systematically searched terms to identify asthma and/or wheeze among children aged <13 years and published between 1995-2020 across seven databases (MEDLINE, EMBASE, PsycINFO, Global Health, AMED, LILACS and CINAHL). PRISMA guidelines were followed for this review.

Results

We extracted a total of 11 886 records, where 190 met our eligibility criteria and included in the analysis. Among the included studies, 62.1% (n = 118/190) used the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaires, predominantly in developing countries (80%, n = 64/80). ‘Wheeze’ was reported in five categories, subdivided by 14 different definitions. “Current wheeze”, defined as caregivers report of wheezing sounds from the chest of the child in the past 12 months and “Wheeze ever”, defined as caregivers’ report of wheezing or whistling in the chest of the child at any previous time, were the most common wheeze category reported in 129 and 95 studies, respectively. Asthma was reported in nine categories using 53 definitions. The most common asthma category was “Asthma ever”, which was reported in 89 studies, based on caregiver statement that the child had asthma in the past.

Conclusion

Definitions of wheeze and asthma for children used in surveys are primarily based on parent-reported clinical features. Studies from developing countries more frequently used the ISAAC definitions to report childhood asthma and wheeze compared to the studies from developed counties. The use of a uniform asthma definition will aid the interpretation of research findings globally.

Prenatal Exposure to Di-Ethyl Phthalate (DEP) Is Related to Increasing Neonatal IgE Levels and the Altering of the Immune Polarization of Helper-T Cells

Introduction: Phthalates are substances that are added to plastic products to increase their plasticity. These substances are released easily into the environment and can act as endocrine disruptors. Epidemiological studies in children have showed inconsistent findings regarding the relationship between prenatal or postnatal exposure to phthalates and the risk of allergic disease. Our hypothesis is that prenatal exposure to phthalates may contribute to the development of allergies in children. Material and methods: The objective of this study was to determine the associations between urinary phthalate metabolite concentrations in pregnant women, maternal atopic diathesis, maternal lifestyle, and cord blood IgE. Pregnant mothers and paired newborns (n = 101) were enrolled from an antenatal clinic. The epidemiologic data and the clinical information were collected using standard questionnaires and medical records. The maternal blood and urine samples were collected at 24–28 weeks gestation, and cord blood IgE, IL-12p70, IL-4, and IL-10 levels were determined from the newborns at birth. The link between phthalates and maternal IgE was also assessed. To investigate the effects of phthalates on neonatal immunity, cord blood mononuclear cells (MNCs) were used for cytokine induction in another in vitro experiment. Results: We found that maternal urine monoethyl phthalate (MEP) (a metabolite of di-ethyl phthalate (DEP)) concentrations are positively correlated with the cord blood IgE of the corresponding newborns. The cord blood IL-12p70 levels of mothers with higher maternal urine MEP groups (high DEP exposure) were lower than mothers with low DEP exposure. In vitro experiments demonstrated that DEP could enhance IL-4 production of cord blood MNCs rather than adult MNCs. Conclusion: Prenatal DEP exposure is related to neonatal IgE level and alternation of cytokines relevant to Th1/Th2 polarization. This suggests the existence of a link between prenatal exposure to specific plasticizers and the future development of allergies.

Effect of dermal phthalate levels on lung function tests in residential area near a petrochemical complex

Phthalates can leach into indoor and outdoor airborne particulate matter and dust, which can then be ingested or absorbed and induce lung injury. Dermal phthalate levels can be used as a matrix for exposure direct absorption from air, particle deposition, and contact with contaminated products. However, the association between dermal phthalate levels in skin wipes and lung function tests remains unknown. A total of 397 participants were included. Spirometry measurements of forced expiratory volume in 1 s (FEV1, L) and forced vital capacity (FVC, L) were calculated. Dermal phthalate levels of diethyl phthalate (DMP), diethyl phthalate (DEP), di(n-butyl) phthalate (DnBP), butyl benzyl phthalate (BBzP), di(2-ethylhexyl) phthalate (DEHP), diisononyl phthalate (DiNP), and diisodecyl phthalate (DiDP) on forehead skin wipes were detected. The one-unit increases in logarithm (log) dermal DnBP (β = - 0.08; 95% CI - 0.16, - 0.003, p = 0.041), BBzP (β = - 0.09; 95% CI - 0.16, - 0.02, p = 0.009), DEHP (β = - 0.07; 95% CI - 0.14, - 0.003, p = 0.042), and DiNP (β = - 0.08; 95% CI - 0.15, - 0.02, p = 0.017) were significantly associated with decreases in FVC. For elderly participants, one-unit increases in log dermal DnBP (β = - 0.25; 95% CI - 0.46, - 0.04, p = 0.021), BBzP (β = - 0.17; 95% CI - 0.33, - 0.01, p = 0.042), and DiDP (β = - 0.19; 95% CI - 0.39, < 0.01, p = 0.052) were associated with decreases in FEV1. In conclusion, dermal phthalate levels were significantly associated with decreases in lung function tests.

Racial/Ethnic Disparities in Pregnancy and Prenatal Exposure to Endocrine-Disrupting Chemicals Commonly Used in Personal Care Products

PURPOSE OF REVIEW

Endocrine-disrupting chemical (EDC) exposure during pregnancy is linked to adverse maternal and child health outcomes that are racially/ethnically disparate. Personal care products (PCP) are one source of EDCs where differences in racial/ethnic patterns of use exist. We assessed the literature for racial/ethnic disparities in pregnancy and prenatal PCP chemical exposures.

RECENT FINDINGS

Only 3 studies explicitly examined racial/ethnic disparities in pregnancy and prenatal exposure to PCP-associated EDCs. Fifty-three articles from 12 cohorts presented EDC concentrations stratified by race/ethnicity or among homogenous US minority populations. Studies reported on phthalates and phenols. Higher phthalate metabolites and paraben concentrations were observed for pregnant non-Hispanic Black and Hispanic women. Higher concentrations of benzophenone-3 were observed in non-Hispanic White women; results were inconsistent for triclosan. This review highlights need for future research examining pregnancy and prenatal PCP-associated EDCs disparities to understand and reduce racial/ethnic disparities in maternal and child health.

Phthalate levels in indoor dust and associations to croup in the SELMA study

Phthalates are ubiquitous indoor pollutants which have been associated with child airway disease although results are inconclusive. This study examined associations between phthalate levels in residential indoor dust and croup during infancy. Settled indoor dust was collected in 482 homes of 6-month-old infants in the Swedish Environmental Longitudinal, Mother and child, Asthma and allergy (SELMA) study and analysed for seven phthalates and one phthalate replacement using gas chromatography tandem mass spectrometry. The incidence of parental reported croup at 12 months was 6.4% for girls and 13.4% for boys. Associations between phthalate dust levels and croup were analysed by logistic regression adjusted for potential confounders. We found significant associations between di-ethyl phthalate (DEP) and di-ethyl-hexyl phthalate (DEHP) in residential dust and parental reported croup (adjusted odds ratio (aOR) = 1.71; 95% CI: 1.08-2.73 and 2.07; 1.00-4.30, respectively). Stratified results for boys showed significant associations between DEP and butyl-benzyl phthalate (BBzP) in dust and infant croup (aOR = 1.86; 95% CI: 1.04-3.34 and 2.02; 1.04-3.90, respectively). Results for girls had questionable statistical power due to few cases. Our results suggest that exposure to phthalates in dust is a risk factor for airway inflammatory responses in infant children.

Associations of dermal diethyl phthalate level with changes in lung function test value mediated by absolute eosinophil count: A panel study of adults in southern Taiwan

Phthalate concentrations in indoor and outdoor dust are associated with respiratory disease. Both immunoglobulin E (IgE) and eosinophil count are associated with airway inflammation from exposure to environmental allergens. Dermal phthalate level can be used as a matrix for assessing personal exposure through direct absorption from the air, particle deposition, or contact with contaminated products. However, the association between dermal phthalate level and changes in lung function test values, as mediated by immunological response, remains unclear. In total, 237 adults in southern Taiwan were recruited. Spirometry measurements (in L) of forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) were taken on visits 1 (2016-2018) and 2 (2019). Dermal phthalate level, absolute eosinophil count, and IgE level were recorded on visit 1. Mean changes in FVC and FEV1 decrease pear year, as determined through pairwise comparisons, were significant (^diffFVC_{per year}: -0.46, 95% CI: -0.51, -0.41; p < 0.001; ^diffFEV1_{per year}: -0.37, 95% confidence interval [CI]: -0.41, -0.34; p < 0.001). For FEV1 decrease, log-unit increases in dermal diethyl phthalate (DEP) were positively associated with ^diffFEV1_{per year} (β = 0.096; 95% CI: 0.042, 0.150; p = 0.001) and negatively associated with absolute eosinophil count (β= -0.201; 95% CI: -0.380, -0.023; p= 0.027). Log-unit increases in absolute eosinophil count were negatively associated with ^diffFEV1_{per year} (β= -0.109; 95% CI: -0.150, -0.068; p < 0.001). Absolute eosinophil count mediated 19.70% of the association between dermal DEP level and ^diffFEV1_{per year}. For FVC decrease, log-unit increases in dermal DEP were positively associated with ^diffFVC_{per year} (β = 0.095; 95% CI: 0.035, 0.155; p = 0.002) and negatively associated with absolute eosinophil count (β = -0.243; 95% CI: -0.427, -0.060; p = 0.010). Log-unit increases in absolute eosinophil count were negatively associated with ^diffFVC_{per year} (β= -0.122; 95% CI: -0.168, -0.076; p < 0.001). Absolute eosinophil count mediated 29.98% of the association between dermal DEP level and ^diffFVC_{per year}. The results suggest that dermal DEP level is positively associated with changes in lung function test values and is mediated by absolute eosinophil count.

Environmental Factor-Mediated Transgenerational Inheritance of Igf2r Hypomethylation and Pulmonary Allergic Response via Targeting Dendritic Cells

The developmental origin of allergic diseases has been suggested, but the molecular basis remains enigmatic. Exposure to environmental factors, such as di-(2-ethylhexyl) phthalate (DEHP; a common plasticizer), is suggested to be associated with increased childhood allergic asthma, but the causal relationship and its underlying mechanism remain unknown. This study explored the transgenerational mechanism of DEHP on allergic asthma and dendritic cell (DC) homeostasis through epigenetic modification. In a murine model, ancestral exposure of C57BL/6 mice to low-dose DEHP led to trans-generational promoter hypomethylation of the insulin-like growth factor 2 receptor (Igf2r), concomitant with enhanced Igf2r expression and increased apoptosis prominently in CD8α+ DCs upon ligand stimulation, with consequent reduction in their IL-12 secretion and subsequent T cell-derived IFN-γ, thereby promoting a default Th2-associated pulmonary allergic response. Increased apoptosis was also noted in circulating IGF2Rhigh human DCs. Further, in human placenta, the methylation level at the orthologous IGF2R promoter region was shown to be inversely correlated with the level of maternal DEHP intake. These results support the importance of ancestral phthalate exposure in conferring the trans-generational risk of allergic phenotypes, featuring hypo-methylation of the IGF2R gene and dysregulated DC homeostasis.

Pregnancy intention and phthalate metabolites among pregnant women in The Infant Development and Environment Study cohort

BACKGROUND

Preconception life style and health play a pivotal role in positively impacting the health of a pregnancy, and this includes the reduction of exposure to endocrine-disrupting chemicals such as phthalates. We have previously demonstrated that women planning a pregnancy with assisted reproductive technology (ART) have lower phthalate metabolite concentrations than their non-ART-using counterparts.

OBJECTIVE

To determine whether women who intended to become pregnant had lower phthalate metabolite concentrations than those who had an unintended pregnancy, or whether change in phthalate exposure across pregnancy differed between these two groups.

METHODS

A total of 721 women enrolled in The Infant Development and Environment Study (TIDES), a multicentre US prospective pregnancy cohort; 513 (71%) indicated their pregnancy was planned. Urine samples from first- and third-trimester visits were analysed for 10 specific-gravity-adjusted, natural-log-transformed phthalate metabolites. Simple and multivariable linear regression, adjusting for centre, race, age, income, marital status, and parity, were employed to determine whether phthalate metabolite concentrations differed by pregnancy intention.

RESULTS

In bivariate analyses, the geometric mean concentrations of all first-trimester and most third-trimester phthalates were higher in women with unplanned pregnancies. However, after covariate adjustment, only first-trimester monoisobutyl phthalate (MiBP) remained associated with pregnancy intention, and the association changed direction such that unplanned pregnancies had lower MiBP concentrations (ß -0.18, 95% CI -0.35, -0.02).

CONCLUSIONS

We did not find evidence of a difference in phthalate exposure between pregnancy planners and non-planners.

A combined cohort analysis of prenatal exposure to phthalate mixtures and childhood asthma

BACKGROUND

Previous studies of prenatal phthalate exposure and childhood asthma are inconsistent. These studies typically model phthalates as individual, rather than co-occurring, exposures. We investigated whether prenatal phthalates are associated with childhood wheeze and asthma using a mixtures approach.

METHODS

We studied dyads from two prenatal cohorts in the ECHO-PATHWAYS consortium: CANDLE, recruited 2006-2011 and TIDES, recruited 2011-2013. Parents reported child respiratory outcomes at age 4-6 years: ever asthma, current wheeze (symptoms in past 12 months) and current asthma (two affirmative responses from ever asthma, recent asthma-specific medication use, and/or current wheeze). We quantified 11 phthalate metabolites in third trimester urine and estimated associations with child respiratory outcomes using weighted quantile sum (WQS) logistic regression, using separate models to estimate protective and adverse associations, adjusting for covariates. We examined effect modification by child sex and maternal asthma.

RESULTS

Of 1481 women, most identified as White (46.6%) or Black (44.6%); 17% reported an asthma history. Prevalence of ever asthma, current wheeze and current asthma in children was 12.3%, 15.8% and 12.3%, respectively. Overall, there was no adverse association with respiratory outcomes. In sex-stratified analyses, boys' phthalate index was adversely associated with all outcomes (e.g., boys' ever asthma: adjusted odds ratio per one quintile increase in WQS phthalate index (AOR): 1.42; 95% confidence interval (CI): 1.08, 1.85, with mono-ethyl phthalate (MEP) weighted highest). Adverse associations were also observed in dyads without maternal asthma history, driven by MEP and mono-butyl phthalate (MBP), but not in those with maternal asthma history. We observed protective associations between the phthalate index and respiratory outcomes in analysis of all participants (e.g., ever asthma: AOR; 95% CI: 0.81; 0.68, 0.96), with di(2-ethylhexyl)phthalate (DEHP) metabolites weighted highest.

CONCLUSIONS

Results suggest effect modification by child sex and maternal asthma in associations between prenatal phthalate mixtures and child asthma and wheeze.

Prenatal phthalate, paraben, and phenol exposure and childhood allergic and respiratory outcomes: Evaluating exposure to chemical mixtures

BACKGROUND

Chemicals found in personal care products and plastics have been associated with asthma, allergies, and lung function, but methods to address real life exposure to mixtures of these chemicals have not been applied to these associations.

METHODS

We quantified urinary concentrations of eleven phthalate metabolites, four parabens, and five other phenols in mothers twice during pregnancy and assessed probable asthma, aeroallergies, and lung function in their age seven children. We implemented Bayesian Profile Regression (BPR) to cluster women by their exposures to these chemicals and tested the clusters for differences in outcome measurements. We used Bayesian Kernel Machine Regression (BKMR) to fit biomarkers into one model as joint independent variables.

RESULTS

BPR clustered women into seven groups characterized by patterns of personal care product and plastic use, though there were no significant differences in outcomes across clusters. BKMR showed that monocarboxyisooctyl phthalate and 2,4-dichlorophenol were associated with probable asthma (predicted probability of probable asthma per IQR of biomarker z-score (standard deviation) = 0.08 (0.09) and 0.11 (0.12), respectively) and poorer lung function (predicted probability per IQR = -0.07 (0.05) and -0.07 (0.06), respectively), and that mono(3-carboxypropyl) phthalate and bisphenol A were associated with aeroallergies (predicted probability per IQR = 0.13 (0.09) and 0.11 (0.08), respectively). Several biomarkers demonstrated positive additive effects on other associations.

CONCLUSIONS

BPR and BKMR are useful tools to evaluate associations of biomarker concentrations within a mixture of exposure and should supplement single-chemical regression models when data allow.

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.

Association between phthalate exposure and asthma risk: A meta-analysis of observational studies

BACKGROUND

Phthalates are ubiquitously found in numerous environments and have been related to a variety of adverse health effects. Previous studies have suggested that phthalate exposure is associated with asthma risk in humans; however, such findings are inconsistent.

METHODS

The aim of the present meta-analysis was to clarify the association between phthalate exposure and asthma risk. A literature search was conducted using PubMed, EMBASE and Web of Science for relevant studies published up to January 5, 2020. Fixed-effects or random-effects models were applied to combine the results, and several subgroup analyses were used to explore the sources of heterogeneity.

RESULTS

A total of 14 studies containing more than 14,000 participants were included in the present study. A positive, significant association between mono-benzyl phthalate (MBzP) levels and asthma risk was found, and the overall odds ratio (OR) was 1.17 (95% confidence interval [CI]: 1.06-1.28, P-value for overall effect [P_z] = 0.001), with a low heterogeneity (P-value for heterogeneity [P_het] = 0.193, I² = 23.6%). The pooled ORs for mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and mono-(2-ethyl-5-carboxypentyl) phthalate (MECPP) concentrations were 1.13 (95% CI: 1.03-1.24, P_z = 0.011) and 1.20 (95% CI: 1.00-1.42, P_z = 0.045), respectively. Children with high levels of MBzP or mono-(carboxynonyl) phthalate (MCNP) were suggested to have increased odds of asthma compared to older populations. In the subgroup analysis by study location, an increased risk for asthma in relation to levels of the sum of di-2-ethylhexyl phthalate (ΣDEHP) was observed in European studies (OR = 1.16, 95% CI: 1.00-1.34, P_z = 0.048) compared to Asia and North America.

CONCLUSIONS

Urinary levels of MBzP, MEHHP, MECPP, MCNP, and DEHP were positively related to asthma risk. No significant association was observed for the other phthalate metabolites in relation to asthma risk. Further research is needed to verify these findings and shed light on the molecular mechanism by which phthalates are associated with asthma.

Lowering Urinary Phthalate Metabolite Concentrations among Children by Reducing Contaminated Dust in Housing Units: A Randomized Controlled Trial and Observational Study

Dust in homes can contain phthalates that may adversely affect child development, but whether residential interventions and dust removal can prevent children's exposure to phthalates is unknown. We quantified the influence of a residential lead hazard intervention and dust control on children's urinary phthalate metabolite concentrations. Between 2003 and 2006, The Health Outcomes and Measures of the Environment (HOME) Study randomized 355 pregnant women to receive an intervention to reduce either residential lead or injury hazards before delivery. We quantified eight urinary phthalate metabolites from 288 children at ages 1, 2, or 3 years (680 observations). During yearly home visits, we assessed dust accumulation in housing units. Children in the lead intervention group had 11-12% lower concentrations of the sum of di(2-ethylhexyl) phthalate metabolites, monocarboxyoctyl phthalate, and monocarboxynonyl phthalate compared to the injury intervention group. Monoethyl phthalate concentrations did not differ by group. In observational analyses, children living in housing units that appeared clean had 12-17% lower concentrations of these phthalate metabolites and monobenzyl phthalate, compared to children living in housing units with more dust accumulation. Features of this lead hazard intervention and measures to control dust may reduce children's exposure to phthalates found in building materials and household furnishings.

Combined exposure to phthalate esters and phosphate flame retardants and plasticizers and their associations with wheeze and allergy symptoms among school children

BACKGROUND

Phthalate esters and phosphate flame retardants and plasticizers (PFRs) are both used as plasticizers and are commonly detected in indoor environments. Although both phthalates and PFRs are known to be associated with children's wheeze and allergic symptoms, there have been no previous studies examining the effects of mixtures of these exposures.

OBJECTIVES

To investigate the association between exposure to mixtures of phthalate esters and PFRs, and wheeze and allergic symptoms among school-aged children.

METHODS

A total of 128 elementary school-aged children were enrolled. Metabolites of 3 phthalate esters and 7 PFRs were measured in urine samples. Parent-reported symptoms of wheeze, rhinoconjunctivitis, and eczema were evaluated using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. In the primary model, we created a phthalate ester and PFR mixture exposure index, and estimated odds ratios (ORs) using weighted quantile sum (WQS) regression and quantile g (qg)-computation. The two highest chemicals according to qg-computation weight %s were combined to create a combination high × high exposure estimate, with ORs calculated using the "low × low" exposure group as the reference category. Concentrations of each metabolite were corrected by multiplying this value by the sex- and body size-Standardised creatinine concentration and dividing by the observed creatinine value. All models were adjusted for sex, grade, dampness index and annual house income.

RESULTS

The odds ratio of rhinoconjunctivitis for the association between exposure to chemical mixtures according to the WQS index positive models was; OR = 2.60 (95% confidence interval [CI]: 1.38-5.14). However, wheeze and eczema of the WQS index positive model, none of the WQS index negative models or qg-computation result yielded statistically significant results. Combined exposure to the two highest WQS weight %s of "high-high" ΣTCIPP and ΣTPHP was associated with an increased prevalence of rhino-conjunctivitis, OR = 5.78 (1.81-18.43) to the "low × low" group.

CONCLUSIONS

Significant associations of mixed exposures to phthalates and PFRs and increased prevalence of rhinoconjunctivitis was found among elementary school-aged children in the WQS positive model. Mixed exposures were not associated with any of allergic symptoms in the WQS negative model or qg-computation approach. However, the combined effects of exposure to two PFRs suggested an additive and/or multiplicative interaction, potentially increasing the prevalence of rhinoconjunctivitis. A further study with a larger sample size is needed to confirm these results.

Longitudinal effect of phthalates exposure on allergic diseases in children

BACKGROUND

Environmental chemicals, such as phthalates, phenols, and parabens, may affect children's immune development and contribute to the risk of atopic diseases and asthma.

OBJECTIVE

To evaluate the associations between prenatal and childhood phthalate exposure and atopic diseases in children at the age of 9 years.

METHODS

This analysis is restricted to 145 mother-child pairs from the prospective Polish Mother and Child Cohort Study. Phthalate metabolite levels were assessed in the urine samples collected from mothers during the third trimester of pregnancy and from children at age of 2 and 9 years. For the appropriate recognition of children's health status, a questionnaire was administered to the mothers and completed with information from the medical record of each child. The clinical examination was performed by a pediatrician/allergist in the presence of the mother or a relative.

RESULTS

A higher urine concentration of mono-2-ethyl-5-oxohexyl phthalate increased the risk of food allergy in children at the age of 9 years (odds ratio [OR], 1.75; 95% CI, 1.19-2.57; P = .004) and decreased the risk of atopic dermatitis (OR, 0.49; 95% CI, 0.27-0.87; P = .02). For mono-2-ethyl-5-hydroxyhexyl phthalate, an increased risk of atopic dermatitis was observed (OR, 1.90; 95% CI, 1.18-3.05; P = .008). A higher urine concentration of mono-benzyl phthalate increased the risk of asthma in children (OR, 1.67; 95% CI, 1.08-2.58; P = .02), but the risk of asthma decreased when the concentration of mono-2-ethylhexyl phthalate was higher (OR, 0.64; 95% CI, 10.43-0.97; P = .04).

CONCLUSION

Our study has not provided clear evidence of the negative effect of phthalate exposure during pregnancy and within the 9 years after birth on allergic diseases in children.

The Role of Environmental Controls in Managing Asthma in Lower-Income Urban Communities

Children living in lower-income urban communities are at much greater risk of developing asthma, going to the emergency department for an asthma attack and being hospitalized for asthma than children living in upper- and middle-income communities. For many asthmatic children living in urban communities, especially those with greater morbidity, the allergic pathway is important in the etiology of the disease. The stages of developing allergic disease can be divided into the onset of allergic sensitization, development of allergic disease and subsequent exacerbations, and it is useful to consider the relevance of interventions at each of these stages. Indoor allergens and environmental exposures are a major contributor to allergic disease, particularly among lower socioeconomic status, urban, minority communities. These exposures include allergens, environmental tobacco smoke, combustion by-products, and mold, all of which can play an important role in asthma progression as well as morbidity. These exposures are often not found in isolation and thus these concomitant exposures need to be considered when conducting environmental interventions. There have been numerous studies looking at both primary and tertiary prevention strategies and the impact on allergic sensitization and asthma with varied results. While the outcomes of these studies have been mixed, what has emerged is the need for tertiary interventions to be targeted to the individual and to reduce all relevant exposures to which an asthmatic child is exposed and sensitized. In addition, effective intervention strategies must also consider other social determinants of asthma morbidity impacting low socioeconomic, urban communities.

Maternal phthalate exposure and asthma, rhinitis and eczema in 552 children aged 5 years; a prospective cohort study

BACKGROUND

Prenatal phthalate exposure has been suggested to alter immune responses and increase the risk of asthma, eczema and rhinitis. However, few studies have examined the effects in prospective cohorts and only one examined rhinitis. We therefore studied associations between maternal urinary concentrations of phthalate metabolites and asthma, eczema and rhinitis in offspring aged 5 years.

METHODS

From 552 pregnant women in the Odense Child Cohort, we quantified urinary concentrations of 12 phthalate metabolites in third trimester. We assessed asthma, rhinitis and eczema in their offspring at age 5 years with a questionnaire based on the International Study of Asthma and Allergies in Childhood (ISAAC), and conducted logistic regression adjusting for relevant confounders.

RESULTS

7.4% of the children had asthma, 11.7% eczema and 9.2% rhinitis. Phthalate exposure was low compared to previous cohorts. No significant associations between prenatal phthalate exposure and asthma were found. Odds ratios (ORs) of child rhinitis with a doubling in ΣDiNP_m and di-2-ethylhexyl phthalate metabolite (ΣDEHP_m) concentrations were, respectively, 1.15 (95% confidence interval (CI) 0.97,1.36) and 1.21 (CI 0.93,1.58). The OR of eczema when doubling ΣDiNP_m was 1.24 (CI 1.00,1.55), whereas the OR of using medicine against eczema when doubling a di-ethyl phthalate (DEP) metabolite was 0.81 (CI 0.68,0.96).

CONCLUSION

The lack of association between maternal phthalate exposure and asthma in the offspring may be due to low exposure and difficulties in determining asthma in 5-year-olds. The higher odds of rhinitis may raise public concern but further research in larger cohorts of older children is warranted.

Influence of Airborne Particles' Chemical Composition on SVOC Uptake from PVC Flooring-Time-Resolved Analysis with Aerosol Mass Spectrometry

We sampled ammonium sulfate particles and indoor particles of outdoor origin through a small chamber covered with polyvinyl chloride flooring. We measured the uptake of semivolatile organic compounds (SVOCs) by the airborne particles in real time. The particles acquired SVOC mass fractions up to 10%. The phthalate ester (di(2-ethylhexyl)phthalate) (DEHP), a known endocrine disruptor, contributed by approximately half of the sorbed SVOC mass. The indoor particles acquired a higher DEHP fraction than laboratory-generated ammonium sulfate aerosol. We attribute this increased uptake to absorption by organic matter present in the indoor particles. Using a thermodenuder to remove volatile components, predominantly organics, reduced the SVOC uptake. Positive matrix factorization applied to the organic mass spectra suggests that hydrocarbon-like organic aerosol (typically fresh traffic exhaust) sorbs DEHP more efficiently than aged organic aerosol. The SVOC uptake is one of the processes that modify outdoor pollution particles after they penetrate buildings, where the majority of exposure occurs. Particles from indoor sources, typically dominated by organic matter, will undergo such processes as well. Aerosol mass spectrometry improves the time resolution of experimental investigations into these processes and enables experiments with lower, relevant particle concentrations. Additionally, particle size-resolved results are readily obtained.

Early life exposure to phthalates in the Canadian Healthy Infant Longitudinal Development (CHILD) study: a multi-city birth cohort

BACKGROUND

Few studies have examined phthalate exposure during infancy and early life, critical windows of development. The Canadian Healthy Infant Longitudinal Development (CHILD) study, a population-based birth cohort, ascertained multiple exposures during early life.

OBJECTIVE

To characterize exposure to phthalates during infancy and early childhood.

METHODS

Environmental questionnaires were administered, and urine samples collected at 3, 12, and 36 months. In the first 1578 children, urine was analyzed for eight phthalate metabolites: mono-methyl phthalate (MMP), mono-ethyl phthalate (MEP), mono-butyl phthalate (MBP), mono-benzyl phthalate (MBzP), mono-2-ethylhexyl phthalate (MEHP), mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono-3-carboxypropyl phthalate (MCPP). Geometric mean (GM) concentrations were calculated by age, together with factors that may influence concentrations. Trends with age were examined using mixed models and differences within factors examined using ANOVA.

RESULTS

The highest urinary concentration was for the metabolite MBP at all ages (GM: 15-32 ng/mL). Concentrations of all phthalate metabolites significantly increased with age ranging from GM: 0.5-15.1 ng/mL at 3 months and 1.9-32.1 ng/mL at 36 months. Concentrations of all metabolites were higher in the lowest income categories except for MEHP at 3 months, among children with any breastfeeding at 12 months, and in urine collected on dates with warmer outdoor temperatures (>17 °C), except for MBzP at 3 months and MEHP at 3 and 12 months. No consistent differences were found by gender, study site, or maternal age.

CONCLUSIONS

Higher phthalate metabolite concentrations were observed among children in lower income families. Examination of factors associated with income could inform interventions aimed to reduce infant phthalate exposure.

Cohort profile: the Neonatal Intensive Care Unit Hospital Exposures and Long-Term Health (NICU-HEALTH) cohort, a prospective preterm birth cohort in New York City

PURPOSE

The Neonatal Intensive Care Unit Hospital Exposures and Long-Term Health (NICU-HEALTH) longitudinal preterm birth cohort studies the impact of the NICU exposome on early-life development. NICU-HEALTH collects multiple biospecimens, complex observational and survey data and comprehensive multisystem outcome assessments to allow measurement of the impact of modifiable environmental exposures during the preterm period on neurodevelopmental, pulmonary and growth outcomes.

PARTICIPANTS

Moderately preterm infants without genetic or congenital anomalies and their mothers are recruited from an urban academic medical centre level IV NICU in New York City, New York, USA. Recruitment began in 2011 and continues through multiple enrolment phases to the present with goal enrolment of 400 infants. Follow-up includes daily data collection throughout the NICU stay and six follow-up visits in the first 2 years. Study retention is 77% to date, with the oldest patients turning age 8 in 2019.

FINDINGS TO DATE

NICU-HEALTH has already contributed significantly to our understanding of phthalate exposure in the NICU. Phase I produced the first evidence of the clinical impact of phthalate exposure in the NICU population. Further study identified specific sources of exposure to clinically relevant phthalate mixtures in the NICU.

FUTURE PLANS

Follow-up from age 3 to 12 is co-ordinated through integration with the Environmental Influences on Child Health Outcomes (ECHO) programme. The NICU-HEALTH cohort will generate a wealth of biomarker, clinical and outcome data from which future studies of the impact of early-life chemical and non-chemical environmental exposures can benefit. Findings from study of this cohort and other collaborating environmental health cohorts will likely translate into improvements in the hospital environment for infant development.

TRIAL REGISTRATION NUMBERS

This observational cohort is registered with ClinicalTrials.gov (NCT01420029 and NCT01963065).

Osborne N. Phthalates and asthma in children and adults: US NHANES 2007-2012

Environmental exposure to phthalates may contribute to an increased risk of asthma in children and adults. We aimed to assess the direction and strength of the association between urinary phthalates metabolites and current asthma in children and adults that participated in the National Health and Nutrition Examination Survey (NHANES) 2007-2012. Data on ten urinary phthalate metabolites, self-reported questionnaires, spirometry measures, and covariates were obtained from 7765 participants (28.1% were children aged 6-17 years) taking part in the NHANES 2007-2012. Asthma was assessed using self-reported questionnaires for children and adults, and via spirometry measures for adults alone. We used crude and adjusted logistic regression models to estimate the odds ratios (ORs) and 95% confidence interval (CI) per one log₁₀ unit change in the concentration of phthalate metabolites. We further modeled the effect modification by sex. Out of 10 metabolites, only mono-benzyl phthalate (MBzP) was positively associated with the prevalence of self-reported asthma in children, after adjusting for a range of potential confounders (odds ratio 1.54; 95% confidence interval 1.05-2.27). No significant relationship was observed for adults. The association of mono-ethyl phthalate (MEP) was modified by sex, with significantly increased odds of asthma among males [boys (2.00; 1.14-3.51); adult males (1.32; 1.04-1.69)]. While no other phthalates showed a positive relationship with current asthma in males, mono-(carboxynonyl) phthalate (MCNP) and mono-(3-carboxylpropyl) phthalate (MCPP) were inversely associated with spirometrically defined asthma in adult females. A sex-specific relationship in adults was evident when spirometry, but not self-reported measures were used to define asthma. We found no clear association between exposure to phthalates and current asthma, except for a significant relationship between MBzP metabolites and self-reported asthma in children. As a result, exposure to phthalates and asthma development and/or exacerbations remains controversial, suggesting a need for a well-designed longitudinal study.

Environmental exposures during windows of susceptibility for breast cancer: a framework for prevention research

Background

The long time from exposure to potentially harmful chemicals until breast cancer occurrence poses challenges for designing etiologic studies and for implementing successful prevention programs. Growing evidence from animal and human studies indicates that distinct time periods of heightened susceptibility to endocrine disruptors exist throughout the life course. The influence of environmental chemicals on breast cancer risk may be greater during several windows of susceptibility (WOS) in a woman’s life, including prenatal development, puberty, pregnancy, and the menopausal transition. These time windows are considered as specific periods of susceptibility for breast cancer because significant structural and functional changes occur in the mammary gland, as well as alterations in the mammary micro-environment and hormone signaling that may influence risk. Breast cancer research focused on these breast cancer WOS will accelerate understanding of disease etiology and prevention.

Main text

Despite the plausible heightened mechanistic influences of environmental chemicals on breast cancer risk during time periods of change in the mammary gland’s structure and function, most human studies of environmental chemicals are not focused on specific WOS. This article reviews studies conducted over the past few decades that have specifically addressed the effect of environmental chemicals and metals on breast cancer risk during at least one of these WOS. In addition to summarizing the broader evidence-base specific to WOS, we include discussion of the NIH-funded Breast Cancer and the Environment Research Program (BCERP) which included population-based and basic science research focused on specific WOS to evaluate associations between breast cancer risk and particular classes of endocrine-disrupting chemicals—including polycyclic aromatic hydrocarbons, perfluorinated compounds, polybrominated diphenyl ethers, and phenols—and metals. We outline ways in which ongoing transdisciplinary BCERP projects incorporate animal research and human epidemiologic studies in close partnership with community organizations and communication scientists to identify research priorities and effectively translate evidence-based findings to the public and policy makers.

Conclusions

An integrative model of breast cancer research is needed to determine the impact and mechanisms of action of endocrine disruptors at different WOS. By focusing on environmental chemical exposure during specific WOS, scientists and their community partners may identify when prevention efforts are likely to be most effective.

Phthalates Exposure and Occupational Symptoms among Slovakian Hairdressing Apprentices

The objectives of the study were to examine occupational exposure to phthalates of hairdressing apprentices from Slovakia (n = 74, 89.2% females; 10.8% males), outcomes related to body composition and pulmonary functions. We used high-performance liquid chromatography and tandem mass spectrometry to the quantified urinary concentration of phthalates. Pulmonary function test (PFT), anthropometric measurements, and questionnaire were also conducted. We observed a decrease of % of predicted values of forced vital capacity (FVC% of PV) related exposure to mono(2-ethyl-5-oxohexyl) phthalate (MEOHP; p = 0.054) and sum of bis(2-ethylhexyl) phthalate metabolites (∑DEHP; p = 0.037), and a decrease of % of predicted values of vital capacity (VC% of PV) related to exposure to MEOHP, ∑DEHP (p = 0.008), and mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP; p = 0.014) in females. We detected associations between forced vital capacity (FVC) with weight (p = 0.002) and fat-free mass index (FFMI, p = 0.010). Vital capacity (VC) and VC% of PV increased with weight, body mass index (BMI), waist circumference (WC), hip circumference (HC), waist-hip ratio (WHR), the waist-height ratio (WHtR), fat mass index (FMI) and FFMI in females (p ≤ 0.014). Results of multivariate regression between PFT and anthropometric parameters adjusted to phthalates indicated exposure to MnBP and MEHP, changing body structure (BMI and FMI), subsequently affecting values of FEV1/FVC.