Residue Levels of Pesticides on Fruits for Use in Wildlife Risk Assessments.

The guidance document on risk assessment for birds and mammals (GD) provides generic residue values of pesticides on potential diet items for use in wildlife risk assessments. For most diet items, these values are based on a large number of residue studies. However, the default residues per unit dose (RUD; standardized for application of 1 kg substance per hectare) values for fruits were taken from a few literature trials of unclear relevance for regulatory purposes. These trials were conducted according to neither current European Union (EU) agricultural practice nor to recommendations given in the GD about how to conduct wildlife-relevant residue studies. Therefore, field study data on fruit residue levels from applications of pesticides in fruiting crops were compiled and evaluated. Corresponding studies had been conducted during the last 26 y in the EU. In the final data set, 291 studies provided 1002 residue values in different fruits, including grapes, berries (currants, raspberries, gooseberries), fruits from orchards (apple, peach, pear, lemon, mandarin, orange, apricot, cherry, plum), gourds (pumpkins, cucumbers, squash, melons), and strawberries. This data set provides a basis for revising registration-relevant RUD values for fruits as potential diet items for birds and mammals in environmental wildlife risk assessments. The objective of this study was to estimate the resulting residue levels in different fruits determined under field conditions following the application of pesticides across their growing areas within the EU in diverse climatic areas that can be used directly in wildlife risk assessments. The large data set of usually about more than 100 residue values per "fruit group," all evaluated at EU member state level, revealed significantly lower RUDs compared to the current default RUDs presented in the GD. These new RUD values for fruits should be considered for use as default values in future bird and mammal risk assessments and in respective guidance documents. Integr Environ Assess Manag 2021;17:552-561. © 2020 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology Chemistry (SETAC).

Appropriate exposure estimates for wildlife risk assessments of crop protection products based on continuous radio telemetry: A case study with woodpigeons.

The registration of pesticides follows guidance published by the European Food Safety Authority (EFSA). As a default, the EFSA guidance document on risk assessment for birds and mammals assumes that animals feed exclusively on pesticide-treated fields. However, the guidance document suggests refining the risk via the proportion of food animals obtain from a treated field or specific crop (expressed via the portion of diet obtained from a treated area [PT value]). The EFSA guidance equalizes the portion of food taken from a treated area per day with the portion of time spent potentially foraging over the course of a day within this area. Therefore, radiotracking is commonly used to gather species-, crop-, and season-specific PT data, and radio telemetry of continuously tracked farmland species can deliver individual PT values for a given day, crop, and species. In the present study the authors introduce a way of calculating long-term PT values based on empirically recorded data via telemetry field studies for the most appropriate use in wildlife risk assessment of pesticides. The novel aspect of the proposal is that the authors follow the prerequisite given by EFSA to cover the long-term risk by introducing 21-d PT values that aim to cover both intra- and inter-individual variability of foraging focal farmland species in cropped habitats. Currently, the intra-individual variability is not taken into account for PT calculations. The authors demonstrate this approach and discuss EFSA guidance input requirements for PT values recorded in field studies, based on a PT field study conducted with woodpigeons (Columba palumbus) radiotracked in an agricultural landscape in the United Kingdom. The results indicate that a 21-d PT value considering intra-individual variability gives a more appropriate PT value for long-term risk assessments. Environ Toxicol Chem 2017;36:1270-1277. © 2016 SETAC.