Science

Carly Hyland, Asa Bradman, Roy Gerona, Sharyle Patton, Igor Zakharevich, Robert B. Gunier, Kendra Klein

Background: Previous diet intervention studies indicate that an organic diet can reduce urinary pesticide metabolite excretion; however, they have largely focused on organophosphate (OP) pesticides. Knowledge gaps exist regarding the impact of an organic diet on exposure to other pesticides, including pyrethroids and neo- nicotinoids, which are increasing in use in the United States and globally.
Objective: To investigate the impact of an organic diet intervention on levels of insecticides, herbicides, and fungicides or their metabolites in urine collected from adults and children.
Methods: We collected urine samples from four racially and geographically diverse families in the United States before and after an organic diet intervention (n = 16 participants and a total of 158 urine samples).
Results: We observed significant reductions in urinary levels of thirteen pesticide metabolites and parent com- pounds representing OP, neonicotinoid, and pyrethroid insecticides and the herbicide 2,4-D following the introduction of an organic diet. The greatest reductions were observed for clothianidin (− 82.7%; 95% confidence interval [95% CI]: − 86.6%, − 77.6%; p < 0.01), malathion dicarboxylic acid (MDA), a metabolite of ma- lathion (− 95.0%; 95% CI: − 97.0%, − 91.8%; p < 0.01), and 3,5,6-trichlor-2-pyridinol (TCPy), a metabolite of chlorpyrifos (− 60.7%; 95% CI: − 69.6%, − 49.2%; p < 0.01). Metabolites or parent compounds of the fungicides boscalid, iprodione, and thiabendazole and the neonicotinoid insecticide imidacloprid were not detected among participants in our study. Conclusion: An organic diet was associated with significant reductions in urinary excretion of several pesticide metabolites and parent compounds. This study adds to a growing body of literature indicating that an organic diet may reduce exposure to a range of pesticides in children and adults. Additional research is needed to evaluate dietary exposure to neonicotinoids, which are now the most widely used class of insecticides in the world.