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ABSTRACT: A conceptual framework was developed by a working group of the Scientific Committee of the European Food Safety Authority (EFSA) to guide risk assessors and risk managers on when and how to integrate ecological recovery and resilience assessments into environmental risk assessments (ERA). In this commentary we advocate that a systems approach is required to integrate the diversity of ecosystem services (ES) providing units, environmental factors, scales, and stressor‐related responses necessary to address the context dependency of recovery and resilience in agricultural landscapes. A future challenge in the resilience assessment remains to identify the relevant bundles of ecosystem services provided by different types of agroecosystem that need to be assessed in concert. Integr Environ Assess Manag 2018;14:586–591. © 2018 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC) [ABSTRACT FROM AUTHOR]

ABSTRACT This article presents a case study demonstrating the application of 3 individual-based, spatially explicit population models (IBMs, also known as agent-based models) in ecological risk assessments to predict long-term effects of a pesticide to populations of small mammals. The 3 IBMs each used a hypothetical fungicide (FungicideX) in different scenarios: spraying in cereals (common vole, Microtus arvalis), spraying in orchards (field vole, Microtus agrestis), and cereal seed treatment (wood mouse, Apodemus sylvaticus). Each scenario used existing model landscapes, which differed greatly in size and structural complexity. The toxicological profile of FungicideX was defined so that the deterministic long-term first tier risk assessment would result in high risk to small mammals, thus providing the opportunity to use the IBMs for risk assessment refinement (i.e., higher tier risk assessment). Despite differing internal model design and scenarios, results indicated in all 3 cases low population sensitivity unless FungicideX was applied at very high (×10) rates. Recovery from local population impacts was generally fast. Only when patch extinctions occured in simulations of intentionally high acute toxic effects, recovery periods, then determined by recolonization, were of any concern. Conclusions include recommendations for the most important input considerations, including the selection of exposure levels, duration of simulations, statistically robust number of replicates, and endpoints to report. However, further investigation and agreement are needed to develop recommendations for landscape attributes such as size, structure, and crop rotation to define appropriate regulatory risk assessment scenarios. Overall, the application of IBMs provides multiple advantages to higher tier ecological risk assessments for small mammals, including consistent and transparent direct links to specific protection goals, and the consideration of more realistic scenarios. Integr Environ Assess Manag 2016;12:46-57. © 2015 SETAC [ABSTRACT FROM AUTHOR]

The aim of the present study was to assess whether population effects and recovery times increase when a population of a vulnerable aquatic invertebrate is exposed to concentrations of 1 or multiple pesticides. The 2 sets of pesticide combinations tested are typical for orchard and tuber crops in The Netherlands. Exposure concentrations were predicted using the FOCUS step 3 modeling framework and the Dutch drainage ditch scenario. Recovery times were assessed using the MASTEP population model. We simulated the population dynamics and pesticide effects in a Monte Carlo style by using median effective concentration values drawn from an arthropod species sensitivity distribution. In the tuber scenario, exposure to λ-cyhalothrin resulted in long-term effects, whereas exposure to the co-occurring compound fluazinam hardly resulted in (additional) effects. In the orchard scenario, 3 pesticides resulted in large effects just after exposure, but pulse exposures to these compounds did not coincide. The probabilities of effects for the single compounds added up for the combination; in contrast, the recovery times were not higher for the combination compared to those associated with exposure to the individual compounds. The conclusion from the present study's simulations is that exposure to the evaluated pesticide packages may lead to increased mortality probabilities and effect sizes of the combination, but does not lead to longer recovery times for populations with synchronized reproduction than when exposed to the individual compounds. Environ Toxicol Chem 2014;33:1489-1498. © 2013 SETAC [ABSTRACT FROM AUTHOR]

ABSTRACT 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. Integr Environ Assess Manag 2014;10:247-259. © 2013 SETAC [ABSTRACT FROM AUTHOR]

Risk and hazard assessments for the soil environment are performed on the basis of the total content of a contaminant in the dry bulk soil. Presently, scientific evidence is emerging and indicating that pore water may be a more relevant exposure medium for uptake of chemicals by biota and plants in soil. To deduce the degree to which pore water concentrations are indeed a better metrics for quantifying uptake of organic chemicals by terrestrial biota (mostly invertebrates), a literature search was performed and the available evidence in favor of any metrics was gathered in the context of a mandate of the European Food Safety Authority. It is concluded that knowledge on uptake routes of contaminants by soil invertebrates is far from complete. Overall it is clear that uptake of organic contaminants depends on species, soil type, and the chemical properties. The mode of exposure of soil invertebrates is determined by the way animals are in contact with their local environment. Morphology, physiology, and behavior are important factors in this respect, as is the mode of uptake of food, water, and oxygen. The contribution of oral uptake may vary within a specific taxon but for soil organisms in close contact with the soil solution, pore water–mediated uptake is in general the dominant pathway and it is commonly modified by soil specific ageing and speciation, and by specific factors of the organisms, such as nutrition status. Residual uptake appears to be the most important uptake route following pore water–mediated uptake. It is likely that in this case, too, pore water is involved as carrier in or at the surface of the soil in which the chemicals are dissolved. Intraspecies (especially between different life stages) and interspecies variances (e.g., size and ecological preferences) will most likely modify the actual contribution of potential exposure pathways, and a distinction must be made between hard-bodied and soft-bodied organisms. Hard-bodied organisms rely for uptake of oxygen and water on specialized organs, whereas water (pore water) and oxygen are mainly taken up via the skin in soft-bodied organisms. Hard-bodied animals are nevertheless in contact with pore water, as shown for spiders, woodlice, and collembolans. Uptake of nutrients and chemicals is possible for all invertebrates via their food, and this may be an important route in case of food sources in which high concentrations of chemicals are present. The assimilation efficiency will however depend on species-specific properties of the digestive tract and no general conclusions are to be generated in this respect. [ABSTRACT FROM AUTHOR]

Ecotoxicological hazard assessment relies on species effect data to estimate quantities such as the predicted no-effect concentration. While there is a concerted effort to quantify uncertainty in risk assessments, the uncertainty due to intertest variability in species effect measurements is an overlooked component. The European Union Registration, Evaluation, Authorisation, and Restriction of Chemicals (REACH) guidance document suggests that multiple toxicity records for a given chemical-species combination should be aggregated by the geometric mean. Ignoring this issue or applying unjustified so-called harmonization methods weakens the defensibility of uncertainty quantification and interpretation about properties of ecological models, for example, the predicted no-effect concentration. In the present study, the authors propose a simple and broadly theoretically justifiable model to quantify intertest variability and analyze it using Bayesian methods. The value of data in ecotoxicity databases is maximized by using (interval-)censored data. An exploratory analysis is provided to support the model. The authors conclude, based on a large ecotoxicity database of acute effects to aquatic species, that the standard deviation of intertest variability is approximately a factor (or fold-difference) of 3. The consequences for decision makers of (not) adjusting for intertest variability are demonstrated. Environ. Toxicol. Chem. 2012; 31: 1903-1910. © 2012 SETAC [ABSTRACT FROM AUTHOR]

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. Integr Environ Assess Manag 2011;7:459-465. © 2011 SETAC [ABSTRACT FROM AUTHOR]

A study of the availability of pesticide-treated seed on arable fields was performed. The research was carried out in three different areas of The Netherlands (soil types ranging between sand and heavy clay) and included the following topics: drilling techniques, soil conditions, location on the field and spillage. The results show that there is a large variation among the various crops in the percentage of seed remaining on the soil surface. This is mainly caused by differences in drilling techniques and soil conditions. The percentage of surface seeds after standard drilling is approximately four times higher than after precision drilling. The best correlation for the impact of soil conditions was found for the overall measure of clod weight. Large differences in seed densities (factor of 3.5) were found between the headland and the field centre. Spillage occurred in most crops investigated, with an average of two spills per field. Based on the field data it is recommended to use in the current risk assessment for birds and mammals the following percentages of seed remaining on the soil surface: 0.5% for precision drilling, 3.3% for standard drilling in spring and 9.2% for standard drilling in autumn. [ABSTRACT FROM AUTHOR]

A model for risk assessment was built for simultaneous, congener-specific PCB bioaccumulation from sediment to fish to otters (Lutra lutra). Toxic equivalence factors (TEFs) were used to sum individual congeners in otters to a toxic equivalent concentration (TEQ) relative to2,3,7,8-tetrachlorodibenzo-p-dioxin. Microbial dechlorination and burial in sediments and bioaccumulation are modeled to predict time trends of PCB concentrations in otters. Effects of accumulated PCBs on otters were assessed for vitamin A metabolism and reproduction, takingmodel uncertainty into account. Three locations in The Netherlands were modeled with PCB levels in sediment of 1 to 171 pg TEQ/g organic carbon (OC). Almost 100% reduction in litter size was predicted for the most polluted area in 1996. Due to large associated uncertainty, aperiod of 25 to 80 years may be needed for recovery of otter vitaminA levels and litter size at this site. Calculated median sediment quality criteria (SQC) range between 1 and 12 pg TEQ/g OC, depending onthe chosen effect criterion. Uncertainty in calculated effects and SQCs is substantial and is mainly caused by uncertainty in PCB congener 126 accumulation. [ABSTRACT FROM AUTHOR]

EFSA requested its Scientific Committee to prepare a guidance document providing generic issues and criteria to consider biological relevance, particularly when deciding on whether an observed effect is of biological relevance, i.e. is adverse (or shows a beneficial health effect) or not. The guidance document provides a general framework for establishing the biological relevance of observations at various stages of the assessment. Biological relevance is considered at three main stages related to the process of dealing with evidence: Development of the assessment strategy. In this context, specification of agents, effects, subjects and conditions in relation to the assessment question(s): Collection and extraction of data; Appraisal and integration of the relevance of the agents, subjects, effects and conditions, i.e. reviewing dimensions of biological relevance for each data set. A decision tree is developed to assist in the collection, identification and appraisal of relevant data for a given specific assessment question to be answered., (© 2017 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.)

EFSA requested the Scientific Committee to develop a guidance document on the use of the weight of evidence approach in scientific assessments for use in all areas under EFSA's remit. The guidance document addresses the use of weight of evidence approaches in scientific assessments using both qualitative and quantitative approaches. Several case studies covering the various areas under EFSA's remit are annexed to the guidance document to illustrate the applicability of the proposed approach. Weight of evidence assessment is defined in this guidance as a process in which evidence is integrated to determine the relative support for possible answers to a question. This document considers the weight of evidence assessment as comprising three basic steps: (1) assembling the evidence into lines of evidence of similar type, (2) weighing the evidence, (3) integrating the evidence. The present document identifies reliability, relevance and consistency as three basic considerations for weighing evidence., (© 2017 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.)

The RAINBOW workshop addressed the background for the integration of in vivo, in vitro and computer-based (in silico) methods, to facilitate the study of the toxic properties of chemicals. On the basis of these discussions, we prepared the present paper, outlining the strengths, weaknesses, opportunities and threats of each approach, both alone and integrated into a single testing strategy. The current scheme for evaluation of chemicals needs to be reshaped, in the face of the much larger numbers of chemicals which need to be examined and the availability of a diversified set of tools., (2010 FRAME.)