Organophosphate Pesticide Exposure and Neurodevelopment in Young Mexican-American Children

BACKGROUND: Organophosphate (OP) pesticides are widely used in agriculture and homes. Animal studies suggest that even moderate doses are neurodevelopmental toxicants, but there are few studies in humans. OBJECTIVES: We investigated the relationship of prenatal and child OP urinary metabolite levels with children’s neurodevelopment. METHODS: Participating children were from a longitudinal birth cohort of primarily Latino farm-worker families in California. We measured six nonspecific dialkylphosphate (DAP) metabolites in maternal and child urine as well as metabolites specific to malathion (MDA) and chlorpyrifos (TCPy) in maternal urine. We examined their association with children’s performance at 6 (n = 396), 12 (n = 395), and 24 (n = 372) months of age on the Bayley Scales of Infant Development [Mental Development (MDI) and Psychomotor Development (PDI) Indices] and mother’s report on the Child Behavior Checklist (CBCL) (n = 356). RESULTS: Generally, pregnancy DAP levels were negatively associated with MDI, but child measures were positively associated. At 24 months of age, these associations reached statistical significance [per 10-fold increase in prenatal DAPs: β = −3.5 points; 95% confidence interval (CI), −6.6 to −0.5; child DAPs: β = 2.4 points; 95% CI, 0.5 to 4.2]. Neither prenatal nor child DAPs were associated with PDI or CBCL attention problems, but both prenatal and postnatal DAPs were associated with risk of pervasive developmental disorder [per 10-fold increase in prenatal DAPs: odds ratio (OR) = 2.3, p = 0.05; child DAPs OR = 1.7, p = 0.04]. MDA and TCPy were not associated with any outcome. CONCLUSIONS: We report adverse associations of prenatal DAPs with mental development and pervasive developmental problems at 24 months of age. Results should be interpreted with caution given the observed positive relationship with postnatal DAPs

Prevalence and Clinical Profile of Severe Acute Respiratory Syndrome Coronavirus 2 Infection among Farmworkers, California, USA, June-November 2020.

During the ongoing coronavirus disease (COVID-19) pandemic, farmworkers in the United States are considered essential personnel and continue in-person work. We conducted prospective surveillance for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and antibody prevalence among farmworkers in Salinas Valley, California, during June 15-November 30, 2020. We observed 22.1% (1,514/6,864) positivity for SARS-CoV-2 infection among farmworkers compared with 17.2% (1,255/7,305) among other adults from the same communities (risk ratio 1.29, 95% CI 1.20-1.37). In a nested study enrolling 1,115 farmworkers, prevalence of current infection was 27.7% among farmworkers reporting >1 COVID-19 symptom and 7.2% among farmworkers without symptoms (adjusted odds ratio 4.16, 95% CI 2.85-6.06). Prevalence of SARS-CoV-2 antibodies increased from 10.5% (95% CI 6.0%-18.4%) during July 16-August 31 to 21.2% (95% CI 16.6%-27.4%) during November 1-30. High SARS-CoV-2 infection prevalence among farmworkers underscores the need for vaccination and other preventive interventions

Gestational exposure to organophosphate pesticides and longitudinally assessed behaviors related to ADHD and executive function

The brain's prefrontal cortex directs higher-order cognitive and behavioral processes that are important for attention, working memory, and inhibitory control. We investigated whether gestational exposure to organophosphate (OP) pesticides was associated with these abilities in childhood and early adolescence. Between 1999 and 2000, we enrolled pregnant women in a birth cohort drawn from an agricultural region of California. We measured dialkyl phosphate (DAP) metabolites of OP pesticides in maternal pregnancy urine samples (13 and 26 weeks) and estimated associations with behaviors related to attention-deficit/hyperactivity disorder and executive function, assessed longitudinally; 351 families provided neurodevelopmental outcome data at any point when the child was aged 7-12 years. We assessed function across multiple dimensions (e.g., working memory, attention), methods (e.g., behavior reports, child assessment), and reporters (e.g., mothers, teachers, child self-reports). Higher gestational DAP concentrations were consistently associated with behaviors related to attention-deficit/hyperactivity disorder and executive function. For example, a 10-fold increase in gestational DAP concentration was associated with poorer longitudinally assessed Behavior Rating Inventory of Executive Function scores, as reported by mothers (β = 4.0 (95% confidence interval: 2.1, 5.8); a higher score indicates more problems), and Weschler Intelligence Scale for Children-Fourth Edition Working Memory scores (a 3.8-point reduction; β = -3.8 (95% confidence interval: -6.2, -1.3)). Reducing gestational exposure to OP pesticides through public health policy is an important goal

Home-based community health worker intervention to reduce pesticide exposures to farmworkers’ children: A randomized-controlled trial

We conducted a randomized-controlled trial of a home-based intervention to reduce pesticide exposures to farmworkers' children in Monterey County, California (n=116 families). The intervention consisted of three home-based educational sessions delivered by community health workers in Spanish. Measurements of organophosphate (OP) insecticide metabolites in child urine (n=106) and pesticides in home floor wipes (n=103) were collected before and after the intervention. Median child urinary dialkyl phosphate (DAP) metabolite levels were slightly lower among the intervention group children at follow-up compared with baseline, albeit nonsignificantly. DAP metabolite levels in the control group children were markedly higher at follow-up compared with baseline. In adjusted models, intervention participation was associated with a 51% decrease in total DAP metabolite levels. Carbaryl, chlorpyrifos, cypermethrin, dacthal, diazinon, malathion, and trans-permethrin were commonly detected in the floor wipes. In adjusted models, intervention participation was significantly associated with a 37% decrease in trans-permethrin floor wipe levels in homes, but not OP or other agricultural pesticides. In summary, intervention group children had slightly reduced pesticide exposures, whereas child exposures were higher among the control group. Additional intervention studies evaluating methods to reduce pesticide exposures to farmworker families and children are needed

Organophosphate pesticide exposure and neurodevelopment in young Mexican-American children.

BackgroundOrganophosphate (OP) pesticides are widely used in agriculture and homes. Animal studies suggest that even moderate doses are neurodevelopmental toxicants, but there are few studies in humans.ObjectivesWe investigated the relationship of prenatal and child OP urinary metabolite levels with children's neurodevelopment.MethodsParticipating children were from a longitudinal birth cohort of primarily Latino farm-worker families in California. We measured six nonspecific dialkylphosphate (DAP) metabolites in maternal and child urine as well as metabolites specific to malathion (MDA) and chlorpyrifos (TCPy) in maternal urine. We examined their association with children's performance at 6 (n = 396), 12 (n = 395), and 24 (n = 372) months of age on the Bayley Scales of Infant Development [Mental Development (MDI) and Psychomotor Development (PDI) Indices] and mother's report on the Child Behavior Checklist (CBCL) (n = 356).ResultsGenerally, pregnancy DAP levels were negatively associated with MDI, but child measures were positively associated. At 24 months of age, these associations reached statistical significance [per 10-fold increase in prenatal DAPs: beta = -3.5 points; 95% confidence interval (CI), -6.6 to -0.5; child DAPs: beta = 2.4 points; 95% CI, 0.5 to 4.2]. Neither prenatal nor child DAPs were associated with PDI or CBCL attention problems, but both prenatal and postnatal DAPs were associated with risk of pervasive developmental disorder [per 10-fold increase in prenatal DAPs: odds ratio (OR) = 2.3, p = 0.05; child DAPs OR = 1.7, p = 0.04]. MDA and TCPy were not associated with any outcome.ConclusionsWe report adverse associations of prenatal DAPs with mental development and pervasive developmental problems at 24 months of age. Results should be interpreted with caution given the observed positive relationship with postnatal DAPs

Changes in Latina Women's Exposure to Cleaning Chemicals Associated with Switching from Conventional to "Green" Household Cleaning Products: The LUCIR Intervention Study.

BackgroundHousehold cleaning products may be a significant source of chemical exposures, including carcinogens and suspected endocrine disruptors.ObjectivesWe characterized exposures during routine household cleaning and tested an intervention to reduce exposures to cleaning product chemicals.MethodsThe Lifting Up Communities with Interventions and Research (LUCIR) Study is a youth-led, community-based intervention project. Youth researchers conducted personal air monitoring with 50 Latina women while they cleaned their homes with their regular cleaning products (preintervention visit) and then 1 week later while they used "green" cleaning products provided by the study (postintervention visit). Air samples were analyzed for volatile and semivolatile organic compounds using gas chromatography-mass spectrometry and high-performance liquid chromatography. We compared pre- and postintervention air concentrations of 47 chemicals of concern, selected because they were on California's Proposition 65 list of carcinogens or reproductive/developmental toxicants or were suspected endocrine disruptors. Youth researchers were integrally involved in the study design, data collection, interpretation, and dissemination of findings.ResultsWe observed statistically significant decreases in air concentrations of 17 chemicals of concern when participants switched to green cleaning products, including decreases in geometric mean concentrations of 1,4-dioxane (-46.4%), chloroform (-86.7%), benzene (-24.8%), naphthalene (-40.3%), toluene (-24.2%), and hexane (-35.5%). We observed significant increases in air concentrations of three fragrance compounds: the plant-derived terpene, beta-myrcene (221.5%), and the synthetic musks celestolide (31.0%) and galaxolide (79.6%). Almost all participants (98%) said the replacement products worked as well as their original products, and 90% said that they would consider buying the replacement products in the future.DiscussionThis study demonstrates that choosing cleaning products that are marketed as green may reduce exposure to several carcinogens and endocrine disruptors. Future studies should determine whether use of unscented green products would further reduce exposure to terpenes and musks. https://doi.org/10.1289/EHP8831

Changes in Latina Women's Exposure to Cleaning Chemicals Associated with Switching from Conventional to "Green" Household Cleaning Products: The LUCIR Intervention Study.

BackgroundHousehold cleaning products may be a significant source of chemical exposures, including carcinogens and suspected endocrine disruptors.ObjectivesWe characterized exposures during routine household cleaning and tested an intervention to reduce exposures to cleaning product chemicals.MethodsThe Lifting Up Communities with Interventions and Research (LUCIR) Study is a youth-led, community-based intervention project. Youth researchers conducted personal air monitoring with 50 Latina women while they cleaned their homes with their regular cleaning products (preintervention visit) and then 1 week later while they used "green" cleaning products provided by the study (postintervention visit). Air samples were analyzed for volatile and semivolatile organic compounds using gas chromatography-mass spectrometry and high-performance liquid chromatography. We compared pre- and postintervention air concentrations of 47 chemicals of concern, selected because they were on California's Proposition 65 list of carcinogens or reproductive/developmental toxicants or were suspected endocrine disruptors. Youth researchers were integrally involved in the study design, data collection, interpretation, and dissemination of findings.ResultsWe observed statistically significant decreases in air concentrations of 17 chemicals of concern when participants switched to green cleaning products, including decreases in geometric mean concentrations of 1,4-dioxane (-46.4%), chloroform (-86.7%), benzene (-24.8%), naphthalene (-40.3%), toluene (-24.2%), and hexane (-35.5%). We observed significant increases in air concentrations of three fragrance compounds: the plant-derived terpene, beta-myrcene (221.5%), and the synthetic musks celestolide (31.0%) and galaxolide (79.6%). Almost all participants (98%) said the replacement products worked as well as their original products, and 90% said that they would consider buying the replacement products in the future.DiscussionThis study demonstrates that choosing cleaning products that are marketed as green may reduce exposure to several carcinogens and endocrine disruptors. Future studies should determine whether use of unscented green products would further reduce exposure to terpenes and musks. https://doi.org/10.1289/EHP8831

Differences in personal care product use by race/ethnicity among women in California: implications for chemical exposures

BackgroundPersonal care products may contain many chemicals, some of which are suspected endocrine disrupters. This is an important source of chemical exposure for women, but little is known about how chemical exposure differs among different races/ethnicities.ObjectiveThis study examines differences in personal care product use among Black, Latina, Vietnamese, Mixed Race, and White women in California.MethodsWe used a community-based participatory process to create and administer a personal care product usage survey to 321 Black, Latina, Vietnamese, Mixed Race, and White women. We used multivariate regression models with pairwise comparisons to examine the frequency of product use by race/ethnicity.ResultsWe found distinct trends of personal care product use by race/ethnicity: Latina women typically used makeup most frequently; Black women used certain hair products or styles most frequently; and Vietnamese women were most likely to use facial cleansing products compared to other races/ethnicities. Latina and Vietnamese women were less likely to try to avoid certain ingredients in their products.SignificanceThese findings can help estimate disparities in chemical exposure from personal care product use and complement future research on health inequities due to chemical exposures in the larger environmental and social context