ABSTRACT
Various health risk assessment models have been developed to evaluate occupational pesticide exposure in China. However, there has been limited investigation into the relationship between health risks and pesticide spraying in orchards. In this study, we analyzed pesticide exposure of applicators while spraying with a stretcher-mounted sprayer in orchards located in four different climatic regions. All garments' unit exposure (UE) demonstrated a right-skewed distribution, with gloves and shins accounting for the highest proportion of dermal pesticide exposure. We observed little difference in dermal and inhalation UE levels between apple and citrus orchards, except for pesticide exposure levels on wipes and faces. While 57% of the inhalation UE distribution variance was attributed to clustering and location effects, no significant differences were observed in dermal exposure levels. We evaluated the impact of different levels of protective clothing on pesticide exposure levels, according to applicators' working habits in China. Our findings revealed that improved levels of protection significantly reduced dermal exposure to pesticides, particularly when wearing gloves during spraying with a stretcher-mounted sprayer. Based on our empirical data, we utilized a simple random sampling model and an intercept-only lognormal mixed model to estimate dermal and inhalation exposure levels. The estimated dermal UE was accurate to within 3-fold with 95% confidence, and half of the estimated inhalation UE was acceptable according to the fold relative accuracy (fRA). Our established and verified statistics for dermal and inhalation UE can be utilized to evaluate the potential pesticide exposure to applicators during spraying in orchards with a stretcher-mounted sprayer.
ABSTRACT
Current research on prothioconazole (PTC), a broad-spectrum triazole fungicide, mainly focuses on its efficacy and residues; only a few studies have been assessing its toxicological effects. Using acute and chronic toxicity tests, we assessed the effects of PTC and its metabolite prothioconazole-desthio (PTCd) on the inhibition of the activity, growth, and reproduction of Daphnia magna. A dose-response relationship was established to determine sensitive biological indicators. In the acute and chronic toxicity tests, the 48-h EC50 (concentration for 50% of the maximal effect) of PTC and PTCd for D. magna were 2.82 and 5.19 mg/L and 0.0807 and 0.132 mg/L, respectively; in the latter test, PTC was 1.64 times more toxic than PTCd. Acute-to-chronic toxicity ratios were calculated using chronic toxicity data; the ratios were 227 and 27.5 for PTC and PTCd, respectively. Our results indicate that both PTC and PTCd affect the growth and reproduction of D. magna and that the toxicity of PTC is greater than that of PTCd. In conclusion, the metabolites of PTD are toxic to D. magna at certain concentrations, and their environmental risks should not be neglected.