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Veröffentlichung New Test Strategy for Dung Beetles During the Authorization Process of Parasiticides(2013) Adler, Nicole; Bachmann, Jean; Römbke, JörgAccording 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. Integr Environ Assess Manag 2013;9:524-530. © 2013 SETACVeröffentlichung An alternative approach to overcome shortcomings with multiple testing of binary data in ecotoxicology(2017) Lehmann, René; Bachmann, Jean; Karaoglan, Bilgin; Lacker, Jens; Polleichtner, ChristianBinary data such as survival, hatching and mortality are assumed to be best described by a binomial distribution. This article provides a simple and straight forward approach for derivation of a no/lowest observed effect level (NOEL/LOEL) in a one-to-many control versus treatments setup. Practically, NOEL and LOEL values can be derived by means of different procedures, e.g. using Fisher̷s exact test in coherence with adjusted p values. However, using adjusted p values heavily decreases statistical power. Alternatively, multiple t tests (e.g. Dunnett test procedure) together with arcsin-square-root transformations can be applied in order to account for variance heterogeneity of binomial data. Arcsin-square-root transformation, however, violates normal distribution because transformed data are constrained, while normal distribution provides data in the range (-8,8). Furthermore, results of statistical tests relying on an approximate normal distribution are approximate too. When testing for trends in probabilities of success (probs), the step down CochranŃArmitage trend test (CA) can be applied. The test statistic used is approximately normal. However, if probs approach 0 or 1, normal approximation of the null-distribution is suboptimal. Thus, critical values and p values lack statistical accuracy. We propose applying the closure principle (CP) and FisherŃFreemanŃHalton test (FISH). The resulting CPFISH can solve the problems mentioned above. CP is used to overcome a-inflation while FISH is applied to test for differences in probs between the control and any subset of treatment groups. Its applicability is presented by means of real data sets. Additionally, we performed a simulation study of 81 different setups (differing numbers of control replicates, numbers of treatments etc.), and compared the results of CPFISH to CA allowing us to point out the advantages and disadvantages of the CPFISH. Quelle: linkspringer.comVeröffentlichung The CPCAT as a novel tool to overcome the shortcomings of NOEC/LOEC statistics in ecotoxicology(2018) Lehmann, René; Bachmann, Jean; Karaoglan, Bilgin; Lacker, Jens; Polleichtner, ChristianSpecies reproduction is an important determinant of population dynamics. As such, this is an important parameter in environmental risk assessment. The closure principle computational approach test (CPCAT) was recently proposed as a method to derive a NOEC/LOEC for reproduction count data such as the number of juvenile Daphnia. The Poisson distribution used by CPCAT can be too restrictive as a model of the data-generating process. In practice, the generalized Poisson distribution could be more appropriate, as it allows for inequality of the population mean ÎÌ and the population variance ÏĆ2 . It is of fundamental interest to explore the statistical power of CPCAT and the probability of determining a regulatory relevant effect correctly. Using a simulation, we varied between Poisson distribution ( ÎÌ=ÏĆ2 ) and generalized Poisson distribution allowing for over-dispersion ( ÎÌ<ÏĆ2 ) and under-dispersion ( ÎÌ>ÏĆ2 ). The results indicated that the probability of detecting the LOEC/NOEC correctly was â 0.8 provided the effect was at least 20% above or below the mean level of the control group and mean reproduction of the control was at least 50 individuals while over-dispersion was missing. Specifically, under-dispersion increased, whereas over-dispersion reduced the statistical power of the CPCAT. Using the well-known Hampel identifier, we propose a simple and straight forward method to assess whether the data-generating process of real data could be over- or under-dispersed.Veröffentlichung Environmental fate and effects assessment of human pharmaceuticals: lessons learnt from regulatory data(2021) Gildemeister, Daniela; Hein, Arne; Schröder, Patrick; Bachmann, Jean; Schwarz, SimonHuman pharmaceuticals are extensively studied and assessed before marketing approval. Since 2006, this also includes an assessment of environmental risks. In the European Union, this is based on the guideline on the environmental risk assessment of medicinal products for human use (EMEA/CHMP/SWP/4447/00 corr 2), which is currently under revision. For Germany, the German Environment Agency (UBA) is tasked with the evaluation of environmental risks of human pharmaceuticals. Applicants seeking approval of medicinal products need to submit fate and effect data, in case predicted environmental concentrations (PECs) exceed 10 ng/L in surface waters, or the substance is of specific concern through its mode of action or physico-chemical characteristics. Over the last decade, this regulatory work resulted in an internal agency database containing effect data on approximately 300 active pharmaceutical ingredients (APIs). A considerable part of this data is currently not publicly available due to property rights held by the respective applicants. The database was evaluated to draw conclusions on how the current assessment approach may be improved. The evaluation of aquatic effect data shows considerable variation in ecotoxic effect concentrations, but supports the current use of 10 ng/L as PEC action limit. For endocrine-active substances and antibiotics, a clear sensitivity profile was observed, which allows a more targeted assessment in the future. The conclusions drawn from terrestrial effect data are less clear, as the database itself is biased because information is only available for substances with high sorption. Further adaptations of the terrestrial assessment strategy, including action triggers, appear necessary. Fate data show a high persistence of many APIs: approximately 43% of all APIs are classified as very persistent; 12% of these show DT50 values in a range where abiotic or biotic degradation is not expected. Overall, the evaluation has shown that improvements of the current guideline are possible. © The Author(s) 2021