Predictors of pesticide levels in carpet dust collected from child care centers in Northern California, USA

Kimberly Hazard; Abbey Alkon; Robert B Gunier; Rosemary Castorina; David Camann; Shraddha Quarderer; Asa Bradman

doi:10.1038/s41370-022-00516-8

Predictors of pesticide levels in carpet dust collected from child care centers in Northern California, USA

J Expo Sci Environ Epidemiol. 2023 Jan 4:1-12. doi: 10.1038/s41370-022-00516-8. Online ahead of print.

Authors

Kimberly Hazard¹, Abbey Alkon², Robert B Gunier³, Rosemary Castorina³, David Camann⁴, Shraddha Quarderer⁴, Asa Bradman⁵

Affiliations

¹ School of Public Health, University of California, Berkeley, CA, USA. hazard@berkeley.edu.
² School of Nursing, University of California, San Francisco, CA, USA.
³ School of Public Health, University of California, Berkeley, CA, USA.
⁴ Southwest Research Institute, San Antonio, TX, USA.
⁵ School of Social Sciences, Humanities and Arts, University of California, Merced, CA, USA.

Abstract

Background: Young children may be exposed to pesticides in child care centers, but little is known about determinants of pesticide contamination in these environments.

Objective: Characterize pesticide contamination in early care and education (ECE) centers and identify predictors of pesticide concentrations and loading in dust collected from classroom carpets.

Methods: Carpet dust samples were collected from 51 licensed child care centers in Northern California and analyzed for 14 structural and agricultural pesticides. Program characteristics were collected through administration of director interviews and observational surveys, including an integrated pest management (IPM) inspection. Pesticide use information for the prior year was obtained from the California Department of Pesticide Regulation to characterize structural applications and nearby agricultural pesticide use.

Results: The most frequently detected pesticides were cis-permethrin (98%), trans-permethrin (98%), bifenthrin (94%), fipronil (94%), and chlorpyrifos (88%). Higher bifenthrin levels were correlated with agricultural applications within 3 kilometers, and higher fipronil levels were correlated with professional pesticide applications in the prior year. In multivariable models, higher IPM Checklist scores were associated with lower loading of chlorpyrifos and permethrin. Placement of the sampled area carpet was also a predictor of chlorpyrifos loading. The strongest predictor of higher pesticide loading for the most frequently detected pesticides was location in California's San Joaquin Valley.

Significance: Our findings contribute to the growing understanding that pesticides are ubiquitous in children's environments. Pesticide levels in carpet dust were associated with some factors that ECE directors may have control over, such as IPM practices, and others that are beyond their control, such as geographic location. IPM is an important tool that has the potential to reduce pesticide exposures in ECE environments, even for pesticides no longer in use.

Impact: One million children in California under six years old attend child care programs where they may spend up to 40 h per week. Children are uniquely vulnerable to environmental contaminants; however early care settings are under researched in environmental health studies. Little is known about predictors of pesticide levels found in environmental samples from child care facilities. This study aims to identify behavioral and environmental determinants of pesticide contamination in California child care centers. Findings can empower child care providers and consumers and inform decision makers to reduce children's exposures to pesticides and promote lifelong health.

Keywords: Child Exposure/Health, Children’s Health, Geospatial Analyses, Pesticides, Vulnerable Populations, Empirical/Statistical Models.