LAUSR

BACKGROUND Pesticides are widely used in fruit orchards. In the context of integrated pest management (IPM) Flemish farmers are advised to restrict the use of pesticides. However, residues of pesticides could still pose a threat to beneficial organisms. To date, it is not well known which residues are present in IPM orchards. This study focuses on the pesticide concentration in the topsoil and the implications for soil-dwelling organisms. RESULTS Topsoil was sampled in ten sweet cherry (Prunus avium (L.) L.) and eight apple (Malus domestica Borkh.) orchards in Flanders (Belgium), to quantify the concentration of pesticide residues. Topsoil was selected because it is a major exposure route for beneficials. Pesticides from current spraying schedules and formerly used pesticides were found. In addition an environmental risk assessment was performed with a species sensitivity distribution (SSD) and a toxicity/exposure ratio (TER) approach. The SSD approach led to a more conservative outcome. None of the pesticides in the spraying schedule revealed a risk, although some of the persistent and banned pesticides still possibly pose a risk. CONCLUSION Spraying schedules are good predictors of environmental contamination. Monitoring residues remains essential to determine the real residue concentration in the topsoil. SSDs proved valuable. It was inferred that besides the standard test with the earthworm Eisenia fetida (Savigny, 1826), an arthropod test organism such as Folsomia candida (Willem, 1902) should be used in future risk assessment, since it displays a higher sensitivity towards insecticides. This article is protected by copyright. All rights reserved.