Trends in airborne pesticides: A retrospective analysis of the last two decades (2007-2024) in a Mediterranean Region.

The potentially adverse effects of pesticide exposure on the general population, and particularly on the more susceptible groups (such as toddlers), are a public health concern. The present study aims to investigate the temporal and spatial fluctuations of pesticides over the past two decades in a rural Mediterranean Region of Spain (the Valencian Region). Overall, a comprehensive analysis of the ambient air revealed the presence of 80 pesticides, including 35 insecticides, 29 fungicides and 11 herbicides, among others. Concentrations detected in Mediterranean ambient air ranged from a few pg m-3 (1.9 for bifenthrin) to millions (1.7 × 106 pg m-3 for malathion). Temporal trends revealed a significant decrease in pesticide concentrations of carbendazim, omethoate and terbuthylazine, whereas others such as metalaxyl and spirotetramat exhibited an increase. The number of pesticides detected and their concentrations were, in general, higher in citrus and vineyards crops compared with other crops assessed. Risk assessment revealed no inhalation risk for adults, with HQ (Hazard Quotient) values well below the threshold level (HQ = 1). However, a single detected concentration at one of the citrus stations showed a potential risk to toddlers due to the pesticide chlorpyrifos-ethyl. Additionally, no cancer risk was observed for either of the populations studied based on average concentrations, although the maximum concentrations of omethoate exceeded the concerned level (1.0 × 10-6).