A longitudinal study comparing the impact of pesticide exposure on cognitive abilities of Latinx children from rural farmworker and urban non-farmworker families

Growing evidence shows that pesticide exposure contributes to numerous adverse health effects. Pesticide exposure can be especially problematic for vulnerable populations, and even more so for children in vulnerable populations who are still developing, such as Latinx children. Several studies have demonstrated the negative cognitive effects of prenatal exposure to pesticides, particularly organophosphates (OPs). We previously reported the results from a baseline study (Dobbins et al., 2022) designed to compare the cognitive abilities of 8-year-old children from rural, farmworking families and urban, non-farmworking families. We found that the children from both populations have considerable pesticide exposure, but to different chemicals. The children of farmworkers had greater exposure to OPs, while the children of non-farmworkers had greater exposure to organochlorines (OCs) and pyrethroids. Using the Weschler Intelligence Scale for Children-Fifth Edition (WISC-V), baseline analyses determined that children of non-farmworkers exhibited lower cognitive scores, specifically on the VSI (visual spatial) and VCI (verbal comprehension) indices. The current study examined the longitudinal significance of these findings in the same participants over a 2-3-year period. We present evidence that children from non-farmworking families exhibited significant declines on the FRI (fluid reasoning index) of the WISC-V. The children from farmworker families did not decline, and this longitudinal difference between the groups was significant. Our findings further suggest that these declines in FRI scores are likely due to greater cumulative OC exposure over the entire longitudinal period.