Risk assessment of pesticide spray drift from citrus applications with air-blast sprayers in Spain

Abstract

There have been no previous risk assessment studies on citrus pesticides in Spain. The aim of this work was to estimate the risks caused by worst-case drift scenarios of the principal pesticides used on the crop, assessing possible damage to the environment and human health. A field survey was carried out, characterizing the specific conditions of plant protection product applications to citrus crops in Spain. Six targets were identified as being the most affected by droplet spray drift in Spain, and more broadly in most Mediterranean conditions: aquatic organisms, earthworms, bees, adult bystanders, child bystanders and residents. Three drift estimation models were used to assess the amount of drift at specific distances downwind of a field in order to calculate Risk Indicators. These showed safe conditions for earthworms and residents, but also indicated that some pesticides may pose a risk to aquatic organisms, even with a 20 m buffer zone, and also to bees, and adult and child bystanders. In general, results generated similar consequences of hazard risk independent of the drift prediction model used, indicating that toxicological data are more relevant for predicting risks.