Integrating NHANES and toxicity forecaster data to compare pesticide exposure and bioactivity by farmwork history and US citizenship

Chanese A Forté; Jess A Millar; Justin A Colacino

doi:10.1038/s41370-023-00583-5

Integrating NHANES and toxicity forecaster data to compare pesticide exposure and bioactivity by farmwork history and US citizenship

J Expo Sci Environ Epidemiol. 2023 Jul 20:10.1038/s41370-023-00583-5. doi: 10.1038/s41370-023-00583-5. Online ahead of print.

Authors

Chanese A Forté^{1

2}, Jess A Millar^{3

4}, Justin A Colacino^{5

6

7}

Affiliations

¹ The University of Michigan School of Public Health, Department of Environmental Health Sciences, Ann Arbor, MI, USA.
² The University of Michigan, College of Engineering, Michigan Institute of Computational Discovery and Engineering, Ann Arbor, MI, USA.
³ The University of Michigan School of Public Health, Department of Epidemiology, Ann Arbor, MI, USA.
⁴ The University of Michigan Medical School, Department of Computational Medicine and Bioinformatics, Ann Arbor, MI, USA.
⁵ The University of Michigan School of Public Health, Department of Environmental Health Sciences, Ann Arbor, MI, USA. colacino@umich.edu.
⁶ The University of Michigan School of Public Health, Department of Nutritional Sciences, Ann Arbor, MI, USA. colacino@umich.edu.
⁷ The University of Michigan College of Literature, Sciences, and the Arts, Program in the Environment, Ann Arbor, MI, USA. colacino@umich.edu.

PMID: 37474644
PMCID: PMC10799167 (available on 2025-01-20)
DOI: 10.1038/s41370-023-00583-5

Abstract

Background: Farmworkers in the United States, especially migrant workers, face unique barriers to healthcare and have documented disparities in health outcomes. Exposure to pesticides, especially those persistent in the environment, may contribute to these health disparities.

Objective: Quantify differences in pesticide exposure bioactivity by farmworker category and US citizenship status.

Methods: We queried the National Health and Nutrition Examination Study (NHANES) from 1999-2014 for pesticide exposure biomarker concentrations among farmworkers and non-farmworkers by citizenship status. We combined this with toxicity assay data from the US Environmental Protection Agency's (EPA's) Toxicity Forecaster (ToxCast). We estimated adverse biological effects that occur across a range of human population-relevant pesticide doses.

Results: In total, there were 844 people with any farmwork history and 23,592 non-farmworkers. Of 12 commonly detectable pesticide biomarkers in NHANES, 2,4-dichlorophenoxyacetic acid (OR = 3.76, p = 1.33 × 10^-6) was significantly higher in farmworkers than non-farmworkers. Farmworkers were 1.15 times more likely to have a bioactive pesticide biomarker measurement in comparison to non-farmworkers (adjusted OR = 1.15, 95% CI: 0.87, 1.51). Non-U.S. citizens were 1.39 times more likely to have bioactive pesticide biomarker concentrations compared to people with U.S. citizenship (adjusted OR 1.39, 95% CI: 1.17, 1.64). Additionally, non-citizens were significantly more exposed to bioactive levels of β-hexachlorocyclohexane (BHC) (OR = 8.10, p = 1.33 × 10^-6), p,p-DDE (OR = 2.60, p = 0.02), and p,p'-DDT (OR = 7.75, p = 0.01).

Impact statement: Farmworkers are a vulnerable population due to social determinants of health and occupational exposures. Here, we integrate US population chemical biomonitoring data and toxicity outcome data to assess pesticide exposure by farmwork history and citizenship. We find that farmworkers and those without US citizenship are significantly more likely to be exposed to concentrations of pesticides which are bioactive in toxicological assays. Thus, farmworkers employed in the US but who are not citizens could be at increased risk of harm to their health due to pesticides. These findings are important to shape evidence-based policies in regulatory science to promote worker safety.

Keywords: Bioactivity; Environmental health; Farmworkers; Occupational health; Pesticides; Toxicology.

Abstract

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