Pesticide Exposure Estimation across Census Tracts in Washington State: Identifying Vulnerable Areas and Populations

INTRODUCTION: Disparities in exposure to and harm associated with pesticides are established. However, high resolution spatial data on exposure to pesticides are lacking. PURPOSE: To describe the development of a pesticide metric for Washington State and to evaluate the associations between pesticide exposure and sociodemographic characteristics of census tracts. METHODS: We used the US cropland data set to quantify the location and size of agricultural land. These data were overlaid with state- and county-level estimated annual agricultural pesticide use to estimate pesticide exposure at the census tract level. Sociodemographic characteristics of census tracts were from the US Centers for Disease Control and Prevention’s Social Vulnerability Index (SVI). Generalized additive models evaluated the associations between pesticide exposure and each of the SVI variables. RESULTS: The median exposure to pesticides was 1.5 lbs/sq mi. Significant associations were observed between exposure to pesticides and a higher percentage of population below poverty, populations unemployed, populations 65 and older, non-Hispanic white populations, those with limited English language proficiency, mobile homes, and group quarters. CONCLUSIONS: The results inform public health and policy efforts to identify areas and populations that are most vulnerable to pesticide exposure and improve the health and well-being of farmworkers and populations residing near agricultural areas.