Effect of a culturally-sensitive pesticide safety training on pesticide exposure and DNA damage levels among indigenous farmworkers in Oregon

Background: Pesticide induced genotoxic damage presents in agricultural populations occupationally exposed to pesticides. Research shows that agricultural populations are at increased risk of hazardous exposure to pesticides, but biomonitoring studies have yet to examine early biological effects of occupational exposure to organophosphate pesticides following receipt of pesticide safety training. Objective: Examine the effect of a culturally-sensitive training targeting farmworkers speaking indigenous languages on pesticide exposure and DNA damage. Method: Nursery workers in Willamette Valley (2010-2011) were randomly assigned to either a promotores or a video-based training. Urine and blood samples from 43 farmworkers were analyzed for (1) DAP urinary metabolites as biomarkers of organophosphate (OP) pesticide exposure and (2) DNA damage as a biomarker of effect using Comet assay, as well as changes in pesticide knowledge scores, were evaluated pre- and post-intervention. Results: No significant changes in pesticide knowledge scores were observed. Both groups showed significant reductions in total metabolite levels from baseline to follow-up; the video group dropped an average of -2.23 ug/g Creatinine (SD=2.72; p=.02) and the promotor group showed an average reduction of -1.86 ug/g Creatinine (SD=1.01; p<0.01). After adjusting for baseline values, follow-up testing revealed a significant reduction in mean comet tail length for the promotor group (post: 40.31 ± 17.27µm vs. pre: 54.29 ±23.22 µm) compared to the video intervention (post: 45.87± 16.13 µm vs. pre: 38.07± 17.87 µm). Conclusion: Our results demonstrate that any culturally-sensitive intervention targeting indigenous farmworkers may reduce exposure and potentially modulate DNA damage in workers occupationally exposed to OP pesticides.