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Focal species have been defined by the European Food Safety Authority (EFSA) as real species that represent others in a crop resulting from their potential higher level of exposure to pesticides. As such they are the most appropriate species for refining estimates of exposure further, through, for example, radio tracking and dietary studies. Plant protection product manufacturers collectively commissioned many studies in Europe, according to the EFSA guidelines, to identify focal species in different crops that may be used in risk assessments for spray applications of pesticides. Using frequency of occurrence in crops and risk-based criteria for exposure, all studies have been reviewed to identify if possible at least 1 focal species per feeding guild, per crop in the new registration zones for southern and central Europe. Some focal species repeatedly appeared across a wide range of arable or tree crops but not both, demonstrating broad adaptation to these 2 different crop structures. Many have widespread distributions, for example, 15 of the focal species have a distribution covering all agricultural regions of Europe (northern, central, and southern zones). Three species, corn bunting, serin, and tree sparrow, are restricted to the central and southern zones, whereas another 4 species, Sardinian and fan-tailed warbler, and crested and short-toed lark, are essentially restricted to the southern zone. The authors consider the focal species identified as suitable for risk assessment in Europe at the zonal level and for further refinement of exposure through studies, such as radio tracking or diet analysis, if necessary., (© 2013 SETAC.)

First-tier risk assessment for pesticides is often based on the quotient of the toxicity divided by the predicted environmental concentration or dose. This ratio is compared to a fixed assessment factor (AF) to decide whether the pesticide is to be allowed on the market or whether further research is needed. Often, a high value (e.g., the 90th percentile) is assumed for the predicted environmental concentration, and the lowest available value is chosen to represent toxicity; yet, the real level of protection is not known. Therefore, it is also not known whether the first tier is conservative enough or too conservative. By using 2 large toxicity databases and assuming a log-logistic species sensitivity distribution for each pesticide, the percent of species not covered by the AF is estimated in the scenario, where exposure is at the maximum level allowable in the first tier. In the case of crustaceans, the median estimate of the fraction of species not covered by the AF of 100 in the first-tier scenario is 3.4%, on average, for 72 pesticides. In other words, on average, 3.4% of the crustacean species will be exposed above their median lethal concentration (LC50) and median lethal dose (LD50) value in 10% of receiving surface waters that receive the maximum allowable exposure to an individual pesticide. The estimated level of protection varies widely between pesticides. For 10% of the pesticides, the estimated fraction of species not covered is ≥10% (maximum=41.4%). For 28% of the pesticides, 99.9% of the species will have the assumed level of protection. For birds, the median estimate of the fraction of species exposed above their median lethal dose for the first-tier scenario (AF=10) is 3.0% on average, when the AF is applied to the lower of the toxicity values for the 2 standard test species. For 11% of the pesticides, the median estimate is ≥10% (maximum=15.7%). When the AF is applied instead to the geometric mean of the toxicity values for the 2 standard species, the median estimate of the fraction of species not covered by the AF is increased to 7.4% on average; for 31% of the pesticides, this fraction is ≥10% (maximum=33.4%). This variation in the level of protection should be considered when defining the assumptions, assessment factors, and decision criteria in regulatory risk assessment., (Copyright © 2011 SETAC.)