NSAIDs detected in Iberian avian scavengers and carrion after diclofenac registration for veterinary use in Spain

Despite the now well recognised impact of diclofenac on vultures across the Indian subcontinent, this non-steroidal anti-inflammatory drug (NSAID) was registered in 2013 for livestock treatment in Spain, Europe's main vulture stronghold. We assessed the risk of exposure to diclofenac and nine other NSAIDs in avian scavengers in the Iberian Peninsula (Spain and Portugal) after the onset of diclofenac commercialization. We sampled 228 livestock carcasses from vulture feeding sites, primarily pig (n = 156) and sheep (n = 45). We also sampled tissues of 389 avian scavenger carcasses (306 Eurasian griffon vultures, 15 cinereous vultures, 11 Egyptian vultures, 12 bearded vultures and 45 other facultative scavengers). Samples were analysed by liquid chromatography with mass spectrometry (LCMS). Seven livestock carcasses (3.07%) contained NSAID residues: flunixin (1.75%), ketoprofen, diclofenac and meloxicam (0.44% each). NSAID residues were only detected in sheep (4.44%) and pig (3.21%) carcasses. Fourteen dead avian scavengers (3.60%) had NSAID residues in kidney and liver, specifically flunixin (1.03%) and meloxicam (2.57%). Flunixin was associated with visceral gout and/or kidney damage in three (0.98%) dead Eurasian griffons. To date, diclofenac poisoning has not been observed in Spain and Portugal, however, flunixin would appear to pose an immediate and clear risk. This work supports the need for well managed carrion disposal, alongside appropriate risk labelling on veterinary NSAIDs and other pharmaceuticals potentially toxic to avian scavengers.

A new ecotoxicological test method for genetically modified plants and other stressors in soil with the black fungus gnat Bradysia impatiens (Diptera): current status of test development and dietary effects of azadirachtin on larval development and emergence rate

BACKGROUND

Few suitable and standardized test methods are currently available to test the effects of genetically modified plants (GMP) on non-target organisms. To fill this gap and improve ecotoxicological testing for GMP, we developed a new soil ecotoxicological test method using sciarid larvae as test organisms.

RESULTS

Bradysia impatiens was identified as a candidate species. Species of the genus Bradysia occur in high numbers in European agroecosystems and B. impatiens can be reared in the laboratory in continuous culture. A functional basic test design was successfully developed. Newly hatched larvae were used as the initial life stage to cover most of the life cycle of the species during the test. Azadirachtin was identified as a suitable reference substance. In several tests, the effects of this substance on development time and emergence rate varied for different temperatures and test substrates. The toxicity was higher at 25 °C compared to 20 °C and in tropical artificial soil compared to coconut fiber substrate.

CONCLUSIONS AND OUTLOOK

Results suggest that the developed test system is suitable to enter a full standardization process, e.g., via the Organisation for Economic Co-operation and Development. Such a standardization would not only assist the risk assessment of GMP, but could include other stressors such as systemic pesticides or veterinary pharmaceuticals reaching the soil, e.g., via spreading manure. The use of sciarid flies as test organisms supports recommendations of EFSA, which stressed the ecological role of flies and encouraged including Diptera into test batteries.

Nontarget effects of ivermectin residues on earthworms and springtails dwelling beneath dung of treated cattle in four countries

The authorization of veterinary medicinal products requires that they be assessed for nontarget effects in the environment. Numerous field studies have assessed these effects on dung organisms. However, few studies have examined effects on soil-dwelling organisms, which might be exposed to veterinary medicinal product residues released during dung degradation. The authors compared the abundance of earthworms and springtails in soil beneath dung from untreated cattle and from cattle treated 0 d, 3 d, 7 d, 14 d, and 28 d previously with ivermectin. Study sites were located in different ecoregions in Switzerland (Continental), The Netherlands (Atlantic), France (Mediterranean), and Canada (Northern Mixed Grassland). Samples were collected using standard methods from 1 mo to 12 mo after pat deposition. Ivermectin concentrations in soil beneath dung pats ranged from 0.02 mg/kg dry weight (3 mo) to typically <0.006 mg/kg dry weight (5-7 mo). Earthworms were abundant and species-rich at the Swiss and Dutch sites, less common with fewer species at the French site, and essentially absent at the Canadian site. Diverse but highly variable communities of springtails were present at all sites. Overall, results showed little effect of residues on either earthworms or springtails. The authors recommend that inclusion of soil organisms in field studies to assess the nontarget effects of veterinary medicinal products be required only if earthworms or springtails exhibit sensitivity to the product in laboratory tests. Environ Toxicol Chem 2016;35:1959-1969. © 2015 SETAC.

New test strategy for dung beetles during the authorization process of parasiticides

According to European legislation, an environmental risk assessment (ERA) of veterinary medicinal products (VMPs) for dung fauna is required in the authorization process, if the substance acts as a parasiticide for the treatment of pasture animals. In the past, however, the demonstration of the environmental safety of those VMPs for dung fauna was strongly hampered by the fact that no standardized tests were available. Therefore, starting with recommendations from the Society of Environmental Toxicology and Chemistry (SETAC) advisory group, dung organism toxicity test standardization (DOTTS) test systems for phase II Tier A standardized tests on the mortality of dung fly and dung beetle larvae were developed and published by the Organisation for Economic Co-operation and Development (OECD) in 2008 and 2010. If a risk is identified for dung organisms in phase II Tier A of the ERA process, further tests are required for Tier B. So far, however, no advice is given for such studies in the existing guidelines. Therefore, 4 workshops took place between 2007 and 2009 with international dung fauna experts (Aveiro-Group) to find an appropriate test strategy for dung fauna organisms beyond Tier A mortality testing. For the first time, 2 different Tier B extended laboratory test approaches for dung beetles and test strategies for scenarios beyond Tier B are described in more detail. In case the risk assessment is still not clear, further options for Tier C (i.e., field studies) or Tier D (modeling) are briefly presented. Finally, the role of uncertainty and variability of test results is discussed, including recommendations for assessment factors for the different tiers to be used when assessing the risk of VMPs on dung organisms. The approach, especially the test strategy, will help industry, consultants, and assessors appropriately assess the environmental risk assessments during the authorization procedure of parasiticides.