Abstract
INTRODUCTION: Growing evidence suggests pesticide exposure can affect emotional well-being; limited research exists across adolescence and young adulthood. We examined cross-sectional and longitudinal associations of pesticide biomarkers with anxiety and depression scores. METHODS: We analyzed 646 participants from Ecuadorian agricultural communities: 510 in 2016 (ages 11-17y) and 485 in 2022 (17-24y). Twelve urinary insecticide metabolites were measured. Validated questionnaires assessed depression and anxiety. Generalized estimating equations (GEE) estimated associations for continuous scores and logit GEE calculated odds ratios (OR) of elevated symptoms, adjusting for demographic and anthropometric variables. RESULTS: In 2016, an interquartile range higher overall pesticides summed (β=1.01 95%CI:[0.48, 1.53]), organophosphates summed (β=0.99 [0.47, 1.51]), 3,5,6-trichloro-2-pyridinol (TCPy; β=0.97 [0.49, 1.45]), pyrethroids summed (β=0.69 [0.11, 1.27]) and 3-phenoxybenzoic acid (β=0.31 [0.01, 0.61]) were positively associated with depression. Detectable 5-hydroxy imidacloprid (OHIM) doubled elevated depression odds. In 2022, higher sulfoxaflor isomers were protective, but higher clothianidin increased elevated depression odds. Longitudinally, depression was positively associated with overall pesticides summed (β=0.06 [0.02, 0.11]), organophosphates summed (β=0.05 [0.001, 0.10]), TCPy (β=0.06 [0.02, 0.10]), pyrethroids summed and trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid (trans-DCCA; β=0.01 [0.003, 0.02]). For anxiety, in 2016 detectable trans-DCCA (OR=2.52 [1.52, 4.16]) was associated with elevated symptoms. In 2022, higher clothianidin increased elevated anxiety odds (OR=1.44 [1.07, 1.93]). Longitudinally, trans-DCCA (OR=1.39 [1.03, 1.87]) and OHIM (OR=1.44 [1.02, 2.04]) increased elevated anxiety odds. CONCLUSIONS: Organophosphates, pyrethroids, and neonicotinoids were generally linked to higher depression and anxiety, while sulfoximines and one organophosphate appeared protective. OHIM and trans-DCCA showed consistent adverse associations across years.