Pyrethroid pesticide exposure and parental report of learning disability and attention-deficit hyperactivity disorder in U.S. children: NHANES 1999-2002.

Background: Use of pyrethroid insecticides has increased dramatically over the past decade; however, data on their potential health effects, particularly on children, are limited. Objective: We examined the cross-sectional association between postnatal pyrethroid exposure and parental report of learning disability (LD) and attention deficit/hyperactivity disorder (ADHD) in children 6–15 years of age. Methods: Using logistic regression, we estimated associations of urinary metabolites of pyrethroid insecticides with parent-reported LD, ADHD, and both LD and ADHD in 1,659–1,680 children participating in the National Health and Nutrition Examination Survey (1999–2002). Results: The prevalence rates of parent-reported LD, ADHD, and both LD and ADHD were 12.7%, 10.0%, and 5.4%, respectively. Metabolite detection frequencies for 3-PBA [3-phenoxybenzoic acid], cis-DCCA [cis-(2,2-dichlorovinyl)-2,2-dimethylcyclopr​opane-1-carboxylicacid], and trans-DCCA [trans-(2,2-dichlorovinyl)-2,2-dimethylcyclopr​opane-1-carboxylicacid] were 77.1%, 35.6%, and 33.9%, respectively. The geometric mean 3-PBA concentration was 0.32 μg/L (median = 0.31 μg/L; interquartile rage = 0.10–0.89 μg/L). cis– and trans-DCCA 75th-percentile concentrations were 0.21 μg/L and 0.68 μg/L, respectively. Log10-transformed 3-PBA concentrations were associated with adjusted odds ratios (ORs) of 1.18 (95% CI: 0.92, 1.51) for parent-reported LD, 1.16 (95% CI: 0.85, 1.58) for ADHD, and 1.45 (95% CI: 0.92, 2.27) for both LD and ADHD. Adjusted ORs remained nonsignificant and decreased after controlling for creatinine and other environmental chemicals previously linked to altered neurodevelopment. Similarly, no significant associations were observed for cis– and trans-DCCA. Conclusions: Postnatal pyrethroid exposure was not associated with parental report of LD and/or ADHD. Given the widespread and increasing use of pyrethroids, future research should evaluate exposures at current levels, particularly during critical windows of brain development.The National Health and Nutrition Examination Survey was conducted by the National Center for Health Statistics, and the data analysis for this research was funded by a Science Innovation Fund from the Passport Foundation. Additional funding was received from the National Institute of Environmental Health Sciences (PO1ES009605) and the U.S. EPA (RD83451301)

Occupational Exposures Among Hair and Nail Salon Workers: a Scoping Review

PURPOSE OF REVIEW: To review the literature published from 2014 to 2019 on hair and nail salon workers concerning exposure assessment, reproductive and respiratory endpoints, and endocrine disruption, in relation to workplace exposures. RECENT FINDINGS: We identified 29 relevant peer-reviewed publications. Overall, there were insufficient studies to determine whether working in these settings is associated with reproductive health endpoints, although prior studies suggest that reproductive effects are of concern. There is consistent evidence that working in hair and nail salons may increase the risk of respiratory effects. Also, despite the fact that many hair and nail care products contain endocrine disrupting compounds, no recent studies have evaluated endocrine-related endpoints. Moreover, few studies have evaluated chemical exposures in these settings and biomonitoring studies are sparse. SUMMARY: Improved exposure assessment of chemical hazards in hair and nail salons is necessary to properly characterize occupational exposures and assess their potential health risks. Further studies on endpoints related to endocrine disruption and reproductive health outcomes among hair and nail salon workers are needed. Improved exposure and epidemiologic studies will help inform chemical exposure mitigation efforts in a vulnerable occupational population, as well as policies related to workplace and consumer product safet

Effect of Organic Diet Intervention on Pesticide Exposures in Young Children Living in Low-Income Urban and Agricultural Communities

Background: Recent organic diet intervention studies suggest that diet is a significant source of pesticide exposure in young children. These studies have focused on children living in suburban communities. Objectives: We aimed to determine whether consuming an organic diet reduced urinary pesticide metabolite concentrations in 40 Mexican-American children, 3–6 years of age, living in California urban and agricultural communities. Methods: In 2006, we collected urine samples over 16 consecutive days from children who consumed conventionally grown food for 4 days, organic food for 7 days, and then conventionally grown food for 5 days. We measured 23 metabolites, reflecting potential exposure to organophosphorous (OP), pyrethroid, and other pesticides used in homes and agriculture. We used linear mixed-effects models to evaluate the effects of diet on urinary metabolite concentrations. Results: For six metabolites with detection frequencies > 50%, adjusted geometric mean concentrations during the organic phase were generally lower for all children, and were significant for total dialkylphosphates (DAPs) and dimethyl DAPs (DMs; metabolites of OP insecticides) and 2,4-D (2,4-dichlorophenoxyacetic acid, a herbicide), with reductions of 40%, 49%, and 25%, respectively (p < 0.01). Chemical-specific metabolite concentrations for several OP pesticides, pyrethroids, and herbicides were either infrequently detected and/or not significantly affected by diet. Concentrations for most of the frequently detected metabolites were generally higher in Salinas compared with Oakland children, with DMs and metolachlor at or near significance (p = 0.06 and 0.03, respectively). Conclusion: An organic diet was significantly associated with reduced urinary concentrations of nonspecific dimethyl OP insecticide metabolites and the herbicide 2,4-D in children. Additional research is needed to clarify the relative importance of dietary and non-dietary sources of pesticide exposures to young children.This research was supported by grants RD-83451301 and RD-83171001 from the U.S. Environmental Protection Agency (EPA), and PO1 ES009605 from the National Institute of Environmental Health Sciences, National Institutes of Health (NIEHS/NIH)

mSpray: A mobile phone technology to improve malaria control efforts and monitor human exposure to malaria control pesticides in Limpopo, South Africa

Recent estimates indicate that malaria has led to over half a million deaths worldwide, mostly to African children. Indoor residual spraying (IRS) of insecticides is one of the primary vector control interventions. However, current reporting systems do not obtain precise location of IRS events in relation to malaria cases, which poses challenges for effective and efficient malaria control. This information is also critical to avoid unnecessary human exposure to IRS insecticides. We developed and piloted a mobile-based application (mSpray) to collect comprehensive information on IRS spray events. We assessed the utility, acceptability and feasibility of using mSpray to gather improved homestead- and chemical-level IRS coverage data. We installed mSpray on 10 cell phones with data bundles, and pilot tested it with 13 users in Limpopo, South Africa. Users completed basic information (number of rooms/shelters sprayed; chemical used, etc.) on spray events. Upon submission, this information as well as geographic positioning system coordinates and time/date stamp were uploaded to a Google Drive Spreadsheet to be viewed in real time. We administered questionnaires, conducted focus groups, and interviewed key informants to evaluate the utility of the app. The low-cost, cell phone-based “mSpray” app was learned quickly by users, well accepted and preferred to the current paper-based method. We recorded 2865 entries (99.1% had a GPS accuracy of 20 m or less) and identified areas of improvement including increased battery life. We also identified a number of logistic and user problems (e.g., cost of cell phones and cellular bundles, battery life, obtaining accurate GPS measures, user errors, etc.) that would need to be overcome before full deployment. Use of cell phone technology could increase the efficiency of IRS malaria control efforts by mapping spray events in relation to malaria cases, resulting in more judicious use of chemicals that are potentially harmful to humans and the environment.This publication was supported by grant numbers: R01 ES020360 and R01 ES020360-S1 from the National Institute of Environmental Health Sciences (NIEHS). We would also like to thank Zinto Corporation, South Africa for donating Smartphones

Organophosphorous pesticide breakdown products in house dust and children’s urine.

Human exposure to preformed dialkylphosphates (DAPs) in food or the environment may affect the reliability of DAP urinary metabolites as biomarkers of organophosphate (OP) pesticide exposure. We conducted a study to investigate the presence of DAPs in indoor residential environments and their association with children’s urinary DAP levels. We collected dust samples from homes in farmworker and urban communities (40 homes total, n=79 samples) and up to two urine samples from resident children ages 3-6 years. We measured six DAPs in all samples and eight DAP-devolving OP pesticides in a subset of dust samples (n=54). DAPs were detected in dust with diethylphosphate (DEP) being the most frequently detected (>=60%); detection frequencies for other DAPs were 0.05). Detection of DEP, chlorpyrifos, or diazinon, was not associated with DEP and/or DEPþdiethylthiophosphate detection in urine (Kappa coefficients=-0.33 to 0.16). Finally, estimated nondietary ingestion intake from DEP in dust was found to be <=5% of the dose calculated from DEP levels in urine, suggesting that ingestion of dust is not a significant source of DAPs in urine if they are excreted unchanged.This work was supported by EPA (RD 83171001) and NIEHS (PO1 ES009605). Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the EPA, NIEHS, or other funders. Additional support was provided by an EPA STAR Doctoral Fellowship (F5D30812), the University of California Institute for Mexico and the United States (UC MEXUS), and the Center for Latino Policy Research at the University of California at Berkeley

Children's residential exposures to flame retardants, pesticides and pesticide degradation products, and the relationship of pesticides with autonomic nervous system functioning

Protecting children's environmental health is a significant public health challenge given children's unique exposure pathways and special vulnerabilities to environmental contaminants compared to adults. This dissertation focused on topics surrounding children's environmental health research with an emphasis on exposure assessment and application in an epidemiologic investigation. The environmental contaminants that this work focused on included pesticides and polybrominated diphenyl ether (PBDE) flame retardants.Chapter 1 provides a general introduction to children's environmental health and highlights the background and significance and specific aims for each study/chapter. Chapter 2 focuses on children's residential exposures via house dust to pesticides and PBDEs in low-income homes. House dust was used to assess indoor residential exposures to these environmental contaminants given that for young children this medium serves as a reservoir for contaminants tracked-in or used indoors and a source of non-dietary ingestion. Additionally, the contaminants of interest have been routinely measured in this medium. In this study, concentrations for 24 pesticides, one pesticide synergist, and three PBDE congeners (major constituents of the pentaBDE flame retardant commercial mixture commonly used on furniture) were measured in house dust samples from farmworker and urban homes in California. Pesticides frequently detected in most homes included: organophosphates (chlorpyrifos and diazinon) which were voluntarily phased-out for residential uses prior to this study by the urging of the United States Environmental Protection Agency (EPA); pyrethroids such as permethrins, allethrins, cypermethrins; and the synergist piperonyl butoxide. Interestingly, chlorthal-dimethyl was detected solely in farmworker homes, suggesting contamination due to regional agricultural use. All three PBDE congeners were detected in all homes and maximum concentrations for each of these congeners are the highest reported to date in house dust (BDE-47: 125 632 ng/g, BDE-99: 218 768 ng/g, BDE-100: 41 149 ng/g). Possible explanations for the high PBDE concentrations observed include California's stringent flammability standards and the presence of poorly constructed or deteriorating furniture treated with PBDEs as previously hypothesized by other researchers. Additionally, diazinon and chlorpyrifos concentrations in Salinas farmworker homes were lower than concentrations reported in samples from Salinas farmworker homes studied between 2000-2002, suggesting a temporal reduction after the U.S. Environmental Protection Agency's voluntary residential phase-out. Lastly, for some resident children, estimated non-dietary PBDE but not pesticide intake exceeded U.S. EPA recommended chronic reference doses (RfDs). In chapter 3 the presence in the environment of dialkylphosphates (DAPs), non-specific urinary OP pesticide metabolites, and their relation to children's urinary DAP metabolites was investigated. Although DAPs were found to be present in the environment, as assessed in house dust, this medium may not play a significant contribution to the DAPs observed in children's urine. The non-dietary ingestion exposure route for environmental DAPs was estimated to be &lt;5% of the dose calculated from DAP levels in children's urine. The distribution of concentrations of diethyl and dimethyl DAPs in dust differed from those observed in children's urine, a finding suggesting that DAPs behave differently in the environment and in the body. However, if humans excrete DAPs unchanged then it is possible for urinary DAPs to reflect exposure to both OP pesticides and DAPs present in one's environment and/or food. Results from this study indicate other sources and pathways, such as DAPs in food, may impact urinary DAP levels more significantly than DAPs in dust. More research is needed on the pharmacokinetics and toxicodynamics of preformed DAPs and other specific OP metabolites to determine the extent of their contribution to urinary biomarkers in humans.In chapter 4 the effects of early life exposures to OP pesticides, as assessed by urinary DAP metabolites, on children's autonomic dysregulation (concomitant sympathetic activation and parasympathetic withdrawal) were assessed at several time points (i.e., when children were 6 months and 1, 3 ½ and 5 years of age). This is the first study to use ANS response measures as outcomes to investigate the association between OP pesticide exposures in children and ANS regulation. The study population was part of the Center for Children's Environmental Health Research longitudinal birth cohort study (CHAMACOS). Children in this cohort live in the Salinas Valley, an agricultural region in California with intense OP pesticide use and were predominantly from Mexico or Mexican-American. Children's autonomic nervous system (ANS) function was assessed using resting and reactivity measures of respiratory sinus arrhythmia (RSA), pre-ejection period (PEP), and heart rate (HR), while OP pesticide exposures were assessed in utero and postnatally by using urinary DAPs. Although the results suggest that OP pesticides at the exposure levels observed are not associated with children's ANS dysregulation, the study focused on a relatively demographically and ethnically homogeneous study population; thus, the results may not be generalizable to other populations. Future investigations in this population will involve evaluating what factors predict ANS regulation and whether ANS resting and reactivity measures of HR, RSA, and PEP are related to later physical and mental problems as observed in prior studies.Finally, chapter 5 highlights the major findings, public health implications and future directions for each chapter/study

Children's residential exposures to flame retardants, pesticides and pesticide degradation products, and the relationship of pesticides with autonomic nervous system functioning

Protecting children's environmental health is a significant public health challenge given children's unique exposure pathways and special vulnerabilities to environmental contaminants compared to adults. This dissertation focused on topics surrounding children's environmental health research with an emphasis on exposure assessment and application in an epidemiologic investigation. The environmental contaminants that this work focused on included pesticides and polybrominated diphenyl ether (PBDE) flame retardants.Chapter 1 provides a general introduction to children's environmental health and highlights the background and significance and specific aims for each study/chapter. Chapter 2 focuses on children's residential exposures via house dust to pesticides and PBDEs in low-income homes. House dust was used to assess indoor residential exposures to these environmental contaminants given that for young children this medium serves as a reservoir for contaminants tracked-in or used indoors and a source of non-dietary ingestion. Additionally, the contaminants of interest have been routinely measured in this medium. In this study, concentrations for 24 pesticides, one pesticide synergist, and three PBDE congeners (major constituents of the pentaBDE flame retardant commercial mixture commonly used on furniture) were measured in house dust samples from farmworker and urban homes in California. Pesticides frequently detected in most homes included: organophosphates (chlorpyrifos and diazinon) which were voluntarily phased-out for residential uses prior to this study by the urging of the United States Environmental Protection Agency (EPA); pyrethroids such as permethrins, allethrins, cypermethrins; and the synergist piperonyl butoxide. Interestingly, chlorthal-dimethyl was detected solely in farmworker homes, suggesting contamination due to regional agricultural use. All three PBDE congeners were detected in all homes and maximum concentrations for each of these congeners are the highest reported to date in house dust (BDE-47: 125 632 ng/g, BDE-99: 218 768 ng/g, BDE-100: 41 149 ng/g). Possible explanations for the high PBDE concentrations observed include California's stringent flammability standards and the presence of poorly constructed or deteriorating furniture treated with PBDEs as previously hypothesized by other researchers. Additionally, diazinon and chlorpyrifos concentrations in Salinas farmworker homes were lower than concentrations reported in samples from Salinas farmworker homes studied between 2000-2002, suggesting a temporal reduction after the U.S. Environmental Protection Agency's voluntary residential phase-out. Lastly, for some resident children, estimated non-dietary PBDE but not pesticide intake exceeded U.S. EPA recommended chronic reference doses (RfDs). In chapter 3 the presence in the environment of dialkylphosphates (DAPs), non-specific urinary OP pesticide metabolites, and their relation to children's urinary DAP metabolites was investigated. Although DAPs were found to be present in the environment, as assessed in house dust, this medium may not play a significant contribution to the DAPs observed in children's urine. The non-dietary ingestion exposure route for environmental DAPs was estimated to be &lt;5% of the dose calculated from DAP levels in children's urine. The distribution of concentrations of diethyl and dimethyl DAPs in dust differed from those observed in children's urine, a finding suggesting that DAPs behave differently in the environment and in the body. However, if humans excrete DAPs unchanged then it is possible for urinary DAPs to reflect exposure to both OP pesticides and DAPs present in one's environment and/or food. Results from this study indicate other sources and pathways, such as DAPs in food, may impact urinary DAP levels more significantly than DAPs in dust. More research is needed on the pharmacokinetics and toxicodynamics of preformed DAPs and other specific OP metabolites to determine the extent of their contribution to urinary biomarkers in humans.In chapter 4 the effects of early life exposures to OP pesticides, as assessed by urinary DAP metabolites, on children's autonomic dysregulation (concomitant sympathetic activation and parasympathetic withdrawal) were assessed at several time points (i.e., when children were 6 months and 1, 3 ½ and 5 years of age). This is the first study to use ANS response measures as outcomes to investigate the association between OP pesticide exposures in children and ANS regulation. The study population was part of the Center for Children's Environmental Health Research longitudinal birth cohort study (CHAMACOS). Children in this cohort live in the Salinas Valley, an agricultural region in California with intense OP pesticide use and were predominantly from Mexico or Mexican-American. Children's autonomic nervous system (ANS) function was assessed using resting and reactivity measures of respiratory sinus arrhythmia (RSA), pre-ejection period (PEP), and heart rate (HR), while OP pesticide exposures were assessed in utero and postnatally by using urinary DAPs. Although the results suggest that OP pesticides at the exposure levels observed are not associated with children's ANS dysregulation, the study focused on a relatively demographically and ethnically homogeneous study population; thus, the results may not be generalizable to other populations. Future investigations in this population will involve evaluating what factors predict ANS regulation and whether ANS resting and reactivity measures of HR, RSA, and PEP are related to later physical and mental problems as observed in prior studies.Finally, chapter 5 highlights the major findings, public health implications and future directions for each chapter/study

Risk perception and use of personal care products by race and ethnicity among a diverse population

Personal care products can contain phthalates, parabens and other endocrine-disrupting chemicals. However, information on perception of risks from personal care product use and how use varies by race and ethnicity is limited. We evaluated differences in personal care product use and risk perception in a diverse sample of participants recruited from a US college campus and online. A self-administered questionnaire captured information on sociodemographic factors, personal care product use trends and perception of risk associated with them. Pearson's chi-square and Fisher's exact tests were used to determine differences in personal care product use and risk perception by race and ethnicity. Ordered logistic regressions were performed to measure associations between personal care product use frequency across racial/ethnic categories. Participant (n = 770) mean age was 22.8 years [standard deviation ± 6.0]. Daily use of make-up (eye = 29.3%; other = 38.0%; all = 33.7%) and skincare products (55%) was most frequently reported among Middle Eastern and North African participants. Non-Hispanic Black participants reported the highest daily use of hairstyling products (52%) and lotion (78%). Daily make-up use was more frequently reported among females (41%) than males (24.6%). Levels of agreement were similar across racial and ethnic groups, that personal care product manufacturers should be required to list all ingredients (≥87%). There were significant associations between the frequency of use of some personal care products and racial/ethnic categories when the use frequencies of participants from other racial/ethnic categories were compared to the use frequency of non-Hispanic White participants. There were significant differences in daily use frequency, levels of trust, perception of safety and health risks associated with personal care products by race and ethnicity, underscoring that there may be different sources of exposure to chemicals in personal care products by race and ethnicity

The exposome : a new approach for risk assessment

Complementing the human genome with an exposome reflects the increasingly obvious impact of environmental exposure, which far exceeds the role of genetics, on human health. Considering the complexity of exposures and, in addition, the reactions of the body to exposures - i.e., the exposome - reverses classical exposure science where the precise measurement of single or few exposures is associated with specific health or environmental effects. The complete description of an individual's exposome is impossible; even less so is that of a population. We can, however, cast a wider net by foregoing some rigor in assessment and compensating with the statistical power of rich datasets. The advent of omics technologies enables a relatively cheap, high-content description of the biological effects of substances, especially in tissues and biofluids. They can be combined with many other rich data-streams, creating big data of exposure and effect. Computational methods increasingly allow data integration, discerning the signal from the noise and formulating hypotheses of exposure-effect relationships. These can be followed up in a targeted way. With a better exposure element in the risk equation, exposomics - new kid on the block of risk assessment - promises to identify novel exposure (interactions) and health/environment effect associations. This may also create opportunities to prioritize the more relevant chemicals for risk assessment, thereby lowering the burden on hazard assessment in an expo-sure-driven approach. Technological developments and synergies between approaches, quality assurance (ultimately as Good Exposome Practices), and the integration of mechanistic thinking will advance this approach.publishe

COVID-19 and children\u27s health in the United States: Consideration of physical and social environments during the pandemic.

Public health measures necessary to counteract the coronavirus disease 2019 (COVID-19) pandemic have resulted in dramatic changes in the physical and social environments within which children grow and develop. As our understanding of the pathways for viral exposure and associated health outcomes in children evolves, it is critical to consider how changes in the social, cultural, economic, and physical environments resulting from the pandemic could affect the development of children. This review article considers the environments and settings that create the backdrop for children's health in the United States during the COVID-19 pandemic, including current threats to child development that stem from: A) change in exposures to environmental contaminants such as heavy metals, pesticides, disinfectants, air pollution and the built environment; B) changes in food environments resulting from adverse economic repercussion of the pandemic and limited reach of existing safety nets; C) limited access to children's educational and developmental resources; D) changes in the social environments at the individual and household levels, and their interplay with family stressors and mental health; E) social injustice and racism. The environmental changes due to COVID-19 are overlaid onto existing environmental and social disparities. This results in disproportionate effects among children in low-income settings and among populations experiencing the effects of structural racism. This article draws attention to many environments that should be considered in current and future policy responses to protect children's health amid pandemics