Overwhelming evidence over many decades has shown that many organic compounds have been released in the environment due to anthropogenic activities. The term “chemicals of emerging concern (CEC)” has been established for chemicals, which are not subjected to marketing restrictions and regulatory monitoring programmes but are candidates for future regulation, due to their frequent detection in environmental samples and their potential hazardous properties (Thomaidis et al, 2012; Gavrilescu et al, 2015; Dulio et al, 2018). Despite the fact that their chemical and physical properties allow them to enter marine, freshwater and/or terrestrial ecosystems, data for the potential bioaccumulation and biomagnification of CECs though the food are missing, which increases the concern about their effects on the ecosystems, biota and human health. CECs, in many studies, are determined by targeted methods, based on the analysis of reference standards (e.g., plant protection products, OCPs, PAHs, PFAS, pharmaceuticals and veterinary medicines). However, despite the high selectivity and sensitivity of targeted methods, using mainly selected reaction monitoring (SRM) mode of detection, they are limited to the determination of a restricted number of compounds. On the other hand, High Resolution Mass Spectrometry (HRMS) techniques, given the high resolution capability (R=35,000) and mass accuracy in full scan mode, have enabled the simultaneous determination of hundreds of emerging contaminants and their transformation products, even if reference standards are not commercially available (Picó et al, 2012; Du et al, 2017). Although thousands of chemicals are marketed in Europe, so far only 600 chemicals have been screened and identified as PBT (persistent, bioaccumulative, toxic), ED (endocrine disrupting) and/or CMR (carcinogenic, mutagenic, toxic for reproduction), because human and environmental hazard assessment is laborious and often obstructed due to the lack of data (ECHA’s 2016 General Report, ECHA 2017). The determination of contaminants in apex predators and their prey (AP&P) allows to identify the emergence of chemicals including substitutes of regulated compounds which may present similar levels of hazard. Apex predators play a key role in the monitoring of environmental contaminants and in risk assessment studies for a number of reasons including: their position at the top of food webs, a relatively long lifespan over which to accumulate contaminants, integration of exposure both over time and relatively large spatial areas, relative ease with which samples can be obtained, and relative ease with which populations can be quantified and monitored (Movalli et al, 2017). The EU funded LIFE APEX project (LIFE17 ENV/SK/000355, 2018-2022), demonstrates the use of AP&P in monitoring contaminants in the environment and assessing the effectiveness of chemicals risk management measures under EU regulations. The aim of LIFE APEX (https://www.lifeapex.eu) is to improve systematic use, by regulators, of chemical monitoring data from apex predators (Harbour Seal, Common Buzzard, Eurasian Otter) and their prey (freshwater fish: Bream/Roach, marine fish: Eelpout/Herring) for better chemicals management, thereby reducing exposure to harmful substances and protecting human health and the environment. LIFE APEX links biota samples from different sample collections with novel analytical methods, for a more thorough understanding of chemicals’ occurrence and bioaccumulation through the food chain. These data can be used for a better prioritization of hazardous substances, their regulation and the effectiveness evaluation of chemicals management. For revealing the presence of CECs in AP & P samples, during the first year of LIFE APEX implementation, 67 recent samples (2015-2019) of apex predators (livers) & their prey (muscles) from four Northern Europe’s countries (United Kingdom, Germany, Netherlands and Sweden), from Environmental Specimen Banks (ESB’s), Natural History Museums (NHM’s) and other scientific collections, were analyzed following state-of-the-art wide-scope target screening methodologies. All samples were lyophilized before analysis, in order to enhance extraction efficiency, improve the precision and achieve lower detection limits. The analytes were extracted from the dry matrices through generic methods of extraction, using Accelerated Solvent Extraction (ASE), followed by a clean-up step using Solid Phase Extraction. The final extracts were analyzed by different chromatographic and ionization techniques (both liquid and gas chromatography) coupled to High Resolution Mass Spectrometry (using electrospray and atmospheric pressure ionization, respectively), in order to broaden the chemical domain accessible to wide-scope target analysis. The samples were screened for the presence of more than 2,400 organic pollutants, included in the target list of the University of Athens (UoA). UoA database includes compounds of different classes (such as pharmaceuticals, personal care products, biocides, plant protection products, illicit drugs, stimulants, sweeteners, and industrial chemicals, e.g. per- and polyfluorinated compounds (PFASs), flame retardants, corrosion inhibitors, plasticizers, surfactants), as well as their transformation products and metabolites. The target list is being updated on a regular basis, since new compounds of concern are continuously being identified. Strict criteria of mass accuracy (<2mDa), isotopic fitting (mSigma<50), retention time (<0.40 min) and fragmentation pattern match were applied during the screening process, while the standard addition method was used for quantification purposes. Preliminary results indicate the presence of several plant protection products (including DEET, myclobutanil and terbuthylazine), stimulants (such as nicotine and its metabolites), sweeteners, industrial chemicals (including benzotriazole and tolytriazole), pharmaceuticals and psychoactive drugs (including sertraline and quetiapine) in the tested samples. Furthermore, numerous transformation products (including propachlor-OXA, Nor-tramadol, 4-acetamido-antipyrine) were detected in livers from apex predators, underlying the power of wide-scope target screening. Moreover, more than 15 PFASs were detected in samples from all tested countries with high detection frequency and at high concentration levels. Based on the results, significantly higher concentrations of chemicals (including perfluorodecanoic acid -PFDA- and propachlor-OXA) were detected in livers from apex predators than in the muscle samples from their prey, implying a potential bioaccumulation through the food chain.

The chemical industry is the leading sector in the EU in terms of added value. However, contaminants pose a major threat and significant costs to the environment and human health. While EU legislation and international conventions aim to reduce this threat, regulators struggle to assess and manage chemical risks, given the vast number of substances involved and the lack of data on exposure and hazards. The European Green Deal sets a 'zero pollution ambition for a toxic free environment' by 2050 and the EU Chemicals Strategy calls for increased monitoring of chemicals in the environment. Monitoring of contaminants in biota can, inter alia: provide regulators with early warning of bioaccumulation problems with chemicals of emerging concern; trigger risk assessment of persistent, bioaccumulative and toxic substances; enable risk assessment of chemical mixtures in biota; enable risk assessment of mixtures; and enable assessment of the effectiveness of risk management measures and of chemicals regulations overall. A number of these purposes are to be addressed under the recently launched European Partnership for Risk Assessment of Chemicals (PARC). Apex predators are of particular value to biomonitoring. Securing sufficient data at European scale implies large-scale, long-term monitoring and a steady supply of large numbers of fresh apex predator tissue samples from across Europe. Natural science collections are very well-placed to supply these. Pan-European monitoring requires effective coordination among field organisations, collections and analytical laboratories for the flow of required specimens, processing and storage of specimens and tissue samples, contaminant analyses delivering pan-European data sets, and provision of specimen and population contextual data. Collections are well-placed to coordinate this. The COST Action European Raptor Biomonitoring Facility provides a well-developed model showing how this can work, integrating a European Raptor Biomonitoring Scheme, Specimen Bank and Sampling Programme. Simultaneously, the EU-funded LIFE APEX has demonstrated a range of regulatory applications using cutting-edge analytical techniques. PARC plans to make best use of such sampling and biomonitoring programmes. Collections are poised to play a critical role in supporting PARC objectives and thereby contribute to delivery of the EU's zero-pollution ambition.

Birds of prey, owls and falcons are widely used as sentinel species in raptor biomonitoring programmes. A major current challenge is to facilitate large-scale biomonitoring by coordinating contaminant monitoring activities and by building capacity across countries. This requires sharing, dissemination and adoption of best practices addressed by the Networking Programme Research and Monitoring for and with Raptors in Europe (EURAPMON) and now being advanced by the ongoing international COST Action European Raptor Biomonitoring Facility. The present perspective introduces a schematic sampling protocol for contaminant monitoring in raptors. We provide guidance on sample collection with a view to increasing sampling capacity across countries, ensuring appropriate quality of samples and facilitating harmonization of procedures to maximize the reliability, comparability and interoperability of data. The here presented protocol can be used by professionals and volunteers as a standard guide to ensure harmonised sampling methods for contaminant monitoring in raptors.

Rats and mice can damage food and agricultural products as well as transmit diseases, thereby requiring control of their numbers. Application of Second Generation Anticoagulant Rodenticides (SGARs) often reduces rodent numbers locally. However, predators eating rodents, including non-target species, that have consumed SGARs may be secondarily exposed and potentially lethally poisoned. Here we study whether SGARs may have contributed to the widespread population declines of a rodent-eating raptor, the Common Kestrel ( Falco tinnunculus ) in the UK. We show that 161 (66.8%) of the 241 Kestrels submitted for ecotoxicology tests between 1997 and 2012 had detectable levels of at least one SGAR in their livers. Adult Kestrels had significantly higher prevalence of SGARs than juveniles, suggesting accumulation of SGARs through time. The prevalence and concentrations of individual SGARs in Kestrels were significantly higher in England than in Scotland. SGAR prevalence in Kestrels were positively associated with some land cover types, primarily arable cereals and broad-leaved woodland , and negatively associated with mainly mean elevation , probably reflecting variation in SGAR usage across land cover types. By using volunteer-collected data on national Kestrel abundance 1997–2012, we show that there is a negative correlation between the Kestrel population index in a specific year and the concentration of bromadialone as well as the total SGAR concentration in the same year. Although correlative, this is the first study to provide evidence for a potential population-limiting effect of SGARs on a raptor.

The term environmental specimen bank (ESB) refers to an organization that collects, preserves, and stores environmental specimens. The first ESB was set up in Sweden in the 1960s but long before that museums (and private individuals) were collecting specimens from all over the world. Specimen banks, and the environmental samples they contain, are a key tool that enables examination of how the environment is affected by, and responding to, major long-term anthropogenic-mediated changes. There are specimen banks in many countries that function to fulfill the following roles: to provide samples that can be used to evaluate wildlife and domestic animal health and human food safety, to investigate trends in environmental change over time, to detect and identify sources of legacy and newly emerging chemicals, to validate computer model predictions and test novel technologies, to test and evaluate government environmental policy and regulations, and to serve as archives for environmental specimens and facilitate specimen use. In this chapter we discuss the role and functioning of ESBs, describe the strict operation of the German ESB, and highlight case studies that have made use of archived samples from the "Predatory Bird Monitoring Scheme" and natural history museum collections.

Risks posed to bees from neonicotinoid seed treatments (clothianidin, thiamethoxam, imidacloprid) led in 2013 to the European Union instigating a moratorium for their use on mass-flowering crops, including oilseed rape in the UK. This restriction did allow for the continued use of these seed treatments, in particular clothianidin, on non-flowering crops like winter wheat. To determine the impacts of the moratorium, we assessed neonicotinoid concentrations pre- (2014) and post- (2015-17) moratorium in 347 honey samples collected across Great Britain. While the probability of detecting clothianidin declined immediately following the moratorium, detection rates remained constant over the following three years (mean = 0.10 ppb, maximum = 2.8 ppb). In contrast, after three years thiamethoxam residues entirely disappeared while detection of imidacloprid was infrequent but persistent over the whole period. For those hives where neonicotinoids were detected, there was no evidence that the concentrations in the honey declined over the three years following the ban. Using metabarcoding approaches, we identified plants foraged upon by honeybees during the production of honey. After the moratorium came into effect, the highest neonicotinoid residues were associated with honey produced by foraging on both oilseed rape and several wild plants found in arable field margins. Concerns about soil persistence and uptake by non-target flowering plants ultimately led to a full European Union ban in 2018. Our results suggest that before this full ban came into effect, the use of clothianidin on non-flowering crops maintained a low-level probability of encountering this neonicotinoid within honey. However, these concentrations were low and would have been unlikely to pose significant risks to honeybees.

The COST Action 'European Raptor Biomonitoring Facility' (ERBFacility) aims to develop pan-European raptor biomonitoring in support of better chemicals management in Europe, using raptors as sentinel species. This presents a significant challenge involving a range of constraints that must be identified and addressed. The aims of this study were to: (1) carry out a comprehensive review of the constraints that may limit the gathering in the field of raptor samples and contextual data, and assess their relative importance across Europe; and (2) identify and discuss possible solutions to the key constraints that were identified. We applied a participatory approach to identify constraints and to discuss feasible solutions. Thirty-one constraints were identified, which were divided into four categories: legal, methodological, spatial coverage, and skills constraints. To assess the importance of the constraints and their possible solutions, we collected information through scientific workshops and by distributing a questionnaire to stakeholders in all the countries involved in ERBFacility. We obtained 74 answers to the questionnaire, from 24 of the 39 COST participating countries. The most important constraints identified were related to the collection of complex contextual data about sources of contamination, and the low number of existing raptor population national/regional monitoring schemes and ecological studies that could provide raptor samples. Legal constraints, such as permits to allow the collection of invasive samples, and skills constraints, such as the lack of expertise to practice necropsies, were also highlighted. Here, we present solutions for all the constraints identified, thus suggesting the feasibility of establishing a long-term European Raptor Sampling Programme as a key element of the planned European Raptor Biomonitoring Facility.

Declining emissions of persistent organic pollutants (POPs), subject to international control under the Stockholm convention, are not consistently reflected in biotic samples. To assess spatial and temporal variation in organochlorine pesticides and PCBs in UK freshwaters, we analysed tissues of a sentinel predator, the Eurasian otter, Lutra lutra between 1992 and 2009. Past declines in otter populations have been linked to POPs and it is unclear whether otter recovery is hampered in any areas by their persistence. PCBs, DDT (and derivatives), dieldrin and HCB were detected in over 80% of 755 otter livers sampled. Concentrations of ∑PCB, ∑DDT and dieldrin in otter livers declined across the UK, but there was no significant time trend for ∑PCB-TEQ (WHO toxic equivalency, Van den Berg et al., 2006) or HCB. In general, higher concentrations were found in the midlands and eastern regions, and lowest concentrations in western regions. Concentrations of PCBs and HCB in otters increased near the coast, potentially reflecting higher pollutant levels in estuarine systems. Decades after legislative controls, concentrations of these legacy pollutants still pose a risk to otters and other freshwater predators, with spatially widespread exceedance of thresholds above which reproduction or survival has been reduced in related species.

Concern on relatively high levels and the potential bioaccumulation of decabromodiphenylether (BDE209) has led to a European 8-year monitoring program on trends in BDE209 concentrations in birds, sewage sludge and sediments from seven countries. BDE209 was analysed in four environmental matrices: sparrowhawk eggs (UK), glaucous gull eggs (Bear Island, Norway), sewage sludge (UK, Ireland and the Netherlands) and sediment (France, Germany, the Netherlands, UK and Ireland). BDE209 was detected in most of the glaucous gull and sparrow hawk eggs but neither increasing nor decreasing trends in these BDE209 levels were observed. An indication for debromination of BDE209 in sparrowhawk eggs was found. BDE209 concentrations in sediments ranged from very low ng/g (88 ng/g on an organic carbon (OC) basis) concentrations, in the rivers Elbe, Ems, Seine and the Outer Humber, to high μg/g (120 μg/g OC), in the Western Scheldt, Liverpool Bay and River Mersey. Apart from decreasing values in the Western Scheldt sediment no further decreases in BDE209 concentrations were observed over time, neither in sediment nor in sewage sludge showing that the voluntary emissions control program of the bromine industry only had a local effect. In contrast to the sewage sludge samples from the Netherlands (mean 355 ng/g dry weight (dw) or 1026 ng/g OC), the BDE209 concentrations in the UK increased at all sites from 2006 to 2011 (8092 ng/g dw or 22,367 ng/g OC). The BDE209 levels in several UK sediments and sewage sludge were still very high at the end of the program in 2012, most likely caused by frequent use of BDE209 in the textile industry. This may be indicative of the persistence of BDE209 and the limited degradation into lower brominated congeners in sediment, although it cannot be excluded that ongoing BDE209 emissions have played a role as well.

Environmental contaminants and parasites are ubiquitous stressors that can affect animal physiology and derive from similar dietary sources (co-exposure). To unravel their interactions in wildlife, it is thus essential to quantify their concurring drivers. Here, the relationship between blood contaminant residues (11 trace elements and 17 perfluoroalkyl substances) and nonlethally quantified gastrointestinal parasite loads was tested while accounting for intrinsic (sex, age, and mass) and extrinsic factors (trophic ecology inferred from stable isotope analyses and biologging) in European shags Phalacrocorax aristotelis. Shags had high mercury (range 0.65-3.21 μg g-1 wet weight, ww) and extremely high perfluorooctanoic acid (PFOA) and perfluorononanoic acid (PFNA) residues (3.46-53 and 4.48-44 ng g-1 ww, respectively). Males had higher concentrations of arsenic, mercury, PFOA, and PFNA than females, while the opposite was true for selenium, perfluorododecanoic acid (PFDoA), and perfluooctane sulfonic acid (PFOS). Individual parasite loads (Contracaecum rudolphii) were higher in males than in females. Females targeted pelagic-feeding prey, while males relied on both pelagic- and benthic-feeding organisms. Parasite loads were not related to trophic ecology in either sex, suggesting no substantial dietary co-exposure with contaminants. In females, parasite loads increased strongly with decreasing selenium:mercury molar ratios. Females may be more susceptible to the interactive effects of contaminants and parasites on physiology, with potential fitness consequences.

We compared long-term (1977 to 2014) trends in concentrations of PFAS in eggs of the marine sentinel species, the Northern gannet (Morus bassanus), from the Irish Sea (Ailsa Craig) and the North Sea (Bass Rock). Concentrations of eight perfluorinated carboxylic acids (PFCAs) and three perfluorinated sulfonates (PFSAs) were determined and we report the first dataset on PFAS in UK seabirds before and after the PFOS ban. There were no significant differences in ∑PFAS or ∑PFSAs between both colonies. The ∑PFSAs dominated the PFAS profile (>80%); PFOS accounted for the majority of the PFSAs (98-99%). In contrast, ∑PFCAs concentrations were slightly but significantly higher in eggs from Ailsa Craig than in those from Bass Rock. The most abundant PFCAs were perfluorotridecanoate (PFTriDA) and perfluoroundecanoate (PFUnA) which, together with PFOA, comprised around 90% of the ∑PFCAs. The ∑PFSAs and ∑PFCAs had very different temporal trends. ∑PFSAs concentrations in eggs from both colonies increased significantly in the earlier part of the study but later declined significantly, demonstrating the effectiveness of the phasing out of PFOS production in the 2000s. In contrast, ∑PFCAs concentrations in eggs were constant and low in the 1970s and 1980s, suggesting minimal environmental contamination, but residues subsequently increased significantly in both colonies until the end of the study. This increase appeared driven by rises in long chain compounds, namely the odd chain numbered PFTriDA and PFUnA. PFOA, had a very different temporal trend from the other dominant acids, with an earlier rise in concentrations followed by a decline in the last 15 years in Ailsa Craig; later temporal trends in Bass Rock eggs were unclear. Although eggs from both colonies contained relatively low concentrations of PFAS, the majority had PFOS residues that exceeded a suggested Predicted No Effect Concentration and ~ 10% of the eggs exceeded a suggested Lowest-Observable-Adverse-Effect.

Following nineteenth-century declines, polecats Mustela putorius are recolonising Great Britain. Polecat diet relates to two potential risks to recovery. First, rabbits Oryctolagus cuniculus , which are important prey for polecats, have experienced extreme population fluctuations, with near extirpation due to myxomatosis in the 1950s, recovery in 1960s–1990s and declines in 1990s–2010s. Second, polecats are secondarily exposed to anticoagulant rodenticides by eating contaminated rodents, and the frequency of polecat exposure to rodenticides is increasing. We analysed stomach contents from 99 polecats collected in 2012–2016 and compared results with earlier studies. Lagomorphs were the most abundant prey (66% frequency of occurrence, 95% confidence interval 53–74%), followed by other mammals (12%, 4–18%), amphibians (10%, 3–16%) and birds (7%, 1–13%). Diet varied seasonally; lagomorph occurrence was highest in spring and summer and lowest in autumn. Dietary niche breadth was greater in the 1960s, when rabbits were scarce, than in other decades, but did not differ between the 1990s and 2010s, indicating that diets have not diversified with recent rabbit declines. This may be because rabbit abundance is not yet low enough to cause dietary diversification or because polecats were collected in areas where rabbits were still abundant. Rodents did not increase in diet between the 1990s and 2010s and still occur with < 10% frequency, indicating that rodents need not contribute much to diet to expose polecats to rodenticides. This potentially limits the effectiveness of management actions designed to minimise polecat exposure to contaminated rodent prey.

Since neonicotinoid insecticides were introduced to the agricultural market, evidence of the negative impacts of these systemic compounds on non-target species has accumulated. Birds are one of the largest groups of species to inhabit farmland, but the extent of neonicotinoid exposure in avian communities is poorly understood and very little is known about how any exposure may affect wild birds. Here, free-living gamebirds were used as a model group to measure the extent of avian exposure to the neonicotinoid dothianidin via seed treatment. During a typical sowing period of winter cereals treated with clothianidin, blood and liver samples were collected simultaneously from individual hunted gamebird carcasses, both pre- (n = 18) and post-sowing (n = 57) and were analysed for dothianidin via LC/MS-MS. Body weight, fat score and faecal parasite load were also quantified in the birds to ascertain whether any of these health parameters were associated with clothianidin exposure under field conditions. Clothianidin was detected in 6% of individuals sampled pre-sowing and 89% of individuals sampled post-sowing. The frequency of dothianidin detection in plasma samples and the concentration of dothianidin in liver and plasma samples decreased significantly between the first week and 2-4 weeks post-sowing. Faecal parasite load was positively associated with concentrations of clothianidin in the liver (but not plasma) of partridge species, but there was no association between clothianidin concentration and fat score or body weight, for either sample type. This study provides clear evidence that treated seed is a source of pesticide exposure for gamebirds following autumn sowing. These findings have implications for gamebirds worldwide where seed treatments are in use, and will aid the design of any future avian biomonitoring studies for agrochemical compounds. (C) 2020 The Authors. Published by Elsevier B.V.

Ingestion of lead (Pb) derived from ammunition used in the hunting of game animals is recognised to be a significant potential source of Pb exposure of wild birds, including birds of prey. However, there are only limited data for birds of prey in Europe regarding tissue concentrations and origins of Pb. Eurasian buzzards (Buteo buteo) found dead in the United Kingdom during an 11-year period were collected and the concentrations of Pb in the liver and femur were measured. Concentrations in the liver consistent with acute exposure to Pb were found in 2.7% of birds and concentration in the femur consistent with exposure to lethal levels were found in 4.0% of individuals. Pb concentration in the femur showed no evidence of consistent variation among or within years, but was greater for old than for young birds. The Pb concentration in the liver showed no effect of the birds' age, but varied markedly among years and showed a consistent tendency to increase substantially within years throughout the UK hunting season for gamebirds. The resemblance of the stable isotope composition of Pb from buzzard livers to that of Pb from the types of shotgun ammunition most widely-used in the UK increased markedly with increasing Pb concentration in the liver. Stable isotope results were consistent with 57% of the mass of Pb in livers of all of the buzzards sampled being derived from shotgun pellets, with this proportion being 89% for the birds with concentrations indicating acute exposure to Pb. Hence, most of the Pb acquired by Eurasian buzzards which have liver concentrations likely to be associated with lethal and sublethal effects is probably obtained when they prey upon or scavenge gamebirds and mammals shot using Pb shotgun pellets.

Toxic metals have been linked to a range of adverse health effects in freshwater organisms. However, for higher vertebrates, there is little understanding of the large-scale drivers of exposure. We quantified toxic metal/semi-metal concentrations in a sentinel freshwater top predator, the Eurasian otter (Lutra lutra), across England and Wales, and determined how this varied with key natural and anthropogenic factors. We related liver concentrations in 278 otters that died between 2006 and 2017 to habitat biogeochemistry, proximity to point source contamination and to biological characteristics (length, sex, condition). Evidence for any positive association with putative anthropogenic sources (mining, human population, known discharges) was weak or lacking in nearly all cases, with the exception of a positive association between lead and human population density. Despite concerns that burgeoning use of nanosilver in consumer products might increase silver concentrations in waste waters, there was no increase over time. Spatial variation in soil/sediment pH, precipitation, and soil calcium oxide are indicated as significant predictors of metal concentrations in otters (higher cadmium and silver in areas with lower pH and higher rainfall, and higher chromium and lead in areas of lower calcium oxide). Liver chromium and nickel concentrations declined significantly over time (Cr 0.030 +/- 1.2 to 0.015 +/- 1.3 mu g/g dry weight, Ni 0.0038 +/- 1.2 to 0.00068 +/- 1.5 mu g/g, between 2006-2009 and 2014-2017), but other metals showed no temporal change. Biotic associations were important, with age related accumulation indicated for mercury and cadmium (as well as interactions with body condition). Our results suggest that larger-scale geochemical and hydrological processes are important in determining metal exposure in otters, and we provide an indication of risk factors that may be of relevance for freshwater vertebrates in other countries with well-developed water pollution management. (C) 2020 The Authors. Published by Elsevier Ltd.

Lead contamination is a widely recognised conservation problem for raptors worldwide. There are a number of studies in individual raptor species but those data have not been systematically evaluated to understand raptor-wide lead exposure and effects at a pan-European scale. To critically assess the extent of this problem, we performed a systematic review compiling all published data on lead in raptors (1983-2019) and, through a meta-analysis, determined if there was evidence for differences in exposure across feeding traits, geographical regions, between hunting and non-hunting periods, and changes over time. We also reviewed the impact of lead on raptors and the likely main source of exposure. We examined 114 studies that were unevenly distributed in terms of time of publication and the countries in which studies were performed. Peer-reviewed articles reported data for 39 raptor species but very few species were widely monitored across Europe. Obligate (vultures) and facultative scavengers (golden eagle, common buzzard and white-tailed sea eagle) accumulated the highest lead concentrations in tissues and generally were the species most at risk of lead poisoning. We found no evidence of a spatial or decadal trend in lead residues, but we demonstrated that high lead blood levels relate to hunting season. Exposure at levels associated with both subclinical and lethal effects is common and lead from rifle bullets and shot is often the likely source of exposure. Overall, our review illustrates the high incidence and ubiquity of lead contamination in raptors in Europe. However, we did not find studies that related exposure to quantitative impacts on European raptor populations nor detailed studies on the impact of mitigation measures. Such information is urgently needed and requires a more harmonised approach to quantifying lead contamination and effects in raptors across Europe.

Insecticides represent an important management tool in agriculture. They provide a low cost and efficacious approach to pest control, where they may be employed both reactively and pre-emptively. It is likely insecticides will continue to play a role in meeting the challenge of feeding a growing global population. The widespread use of insecticides creates potential for negative impacts on non-target invertebrate populations. Many countries have regulatory processes in place to manage these. However, there regulatory processes have potential limitations when it comes to detecting the long-term and large-scale consequences of insecticide use. For example, long-term sub-lethal effects resulting from low dose exposure durations are rarely considered in toxicity tests, while predictable additive effects of mixtures of active ingredient are often ignored. In order to address this data gap, there is substantial scope for using existing spatially and temporally explicit biological records of species occurrence. This could help in monitoring and assessment to support our responsibilities to maintain biodiversity while continuing to grow enough food to feed the human population. How this is achieved poses several problems, both practical and analytical. Here, we describe how national-scale data on the spatial and temporal distribution of native invertebrates can be combined with maps of large-scale insecticide application and exposure risk to explore the actual consequences for non-target native biodiversity. Understanding these impacts on native invertebrates will provide a vital evidence base to inform policy decisions that could complement existing regulatory processes.

Biomonitoring in raptors can be used to study long-term and large-scale changes in environmental pollution. In Europe, such monitoring is needed to assess environmental risks and outcomes of chemicals regulation, which is harmonised across the European Union. To be effective, the most appropriate sentinels need to be monitored. Our aim was to identify which European raptor species are the likely most appropriate biomonitors when pollutant quantification is based on analysing tissues. Our current study was restricted to terrestrial exposure pathways and considered four priority pollutant groups: toxic metals (lead and mercury), anticoagulant rodenticides, pesticides and medicinal products. We evaluated information on the distribution and key ecological traits (food web, foraging trait, diet, preferred habitat, and migratory behaviour) of European raptors to identify the most appropriate sentinel species. Common buzzard (Buteo buteo) and/or tawny owl (Strix aluco) proved the most suitable candidates for many of the pollutants considered. Moreover, they are abundant in Europe, enhancing the likelihood that samples can be collected. However, other species may be better sentinels for certain pollutants, such as the golden eagle (Aquila chrysaetos) for lead, the northern goshawk (Accipiter gentilis) for mercury across areas including Northern Europe, and vultures (where they occur in Europe) are likely best suited for monitoring non-steroidal anti-inflammatory drugs (NSAIDs). Overall, however, we argue the selection of candidate species for widescale monitoring of a range of pollutants can be reduced to very few raptor species. We recommend that the common buzzard and tawny owl should be the initial focus of any pan-European raptor monitoring. The lack of previous widespread monitoring using these species suggests that their utility as sentinels for environmnetal pollution has not been widely recognised. Finally, although the current study focussed on Europe, our trait-based approach for identifying raptor biomonitors can be applied to other continents and contaminants.