The Panel has interpreted the Terms of Reference by carrying out a stepwise evaluation of the BEEHAVE simulation model with a view to assessing its suitability for use in a regulatory context and for risk assessment of multiple stressors at the landscape level. The EFSA opinion on good modelling practice was used to evaluate the model and its documentation systematically. The overall conclusion is that BEEHAVE performs well in modelling honeybee colony dynamics, and the supporting documentation is generally good but does not fully meet the criteria of the good modelling opinion. BEEHAVE is not yet usable in a regulatory context primarily because it needs a pesticide module. BEEHAVE has a Varroa/virus module, although this seems to underestimate the impact of Varroa/virus on colony survival, and additional stressors (chemical and biological) would need to be added to allow investigation of the effects of interactions of pesticides with multiple stressors. BEEHAVE currently uses a very simple representation of a landscape and this should be extended. There is only one environmental scenario in the present version of BEEHAVE (European central zone-weather scenarios for Germany and the UK) and extension to other European zones would be needed. The supporting data and default parameter values should be further evaluated and justified. The modelling environment used by BEEHAVE (NetLogo) has an excellent user interface but provides limited opportunities for extending the model. The Panel recommends that BEEHAVE should be adopted as the basis for modelling the impact on honeybee colonies of pesticides and other stressors, but that further development should use a standard, object-oriented language rather than NetLogo. The evaluation of the model follows the structure and recommendations in the scientific opinion on good modelling practice (EFSA PPR Panel, 2014), which is intended to help evaluation of models that are submitted in a regulatory context for pesticide risk assessment. The BEEHAVE model was developed before the opinion on good modelling practice was published and it was not submitted in a regulatory context. Therefore, it is not surprising that the BEEHAVE model does not fulfil all the criteria outlined in the good modelling practice opinion and that some of the criteria are not applicable to BEEHAVE. In order to allow a balanced evaluation of the model, it was decided that the model should first be evaluated against its original purpose (to explore how various stressors such as Varroa mites, virus infections, impaired foraging behaviour, changes in landscape structure and dynamics and pesticides affect, in isolation and combination, the performance and possible decline and failure of single managed colonies of honeybees). Where relevant, it was then evaluated against its potential use in a regulatory context and for the assessment of the risk from multiple stressors at the landscape level.In terms of evaluation of the conceptual model, the current model addresses most points of its problem formulati...
Bats are an important group of mammals, frequently foraging in farmland and potentially exposed to pesticides. This statement considers whether the current risk assessment performed for birds and ground dwelling mammals exposed to pesticides is also protective of bats. Three main issues were addressed. Firstly, whether bats are toxicologically more or less sensitive than the most sensitive birds and mammals. Secondly, whether oral exposure of bats to pesticides is greater or lower than in ground dwelling mammals and birds. Thirdly, whether there are other important exposure routes relevant to bats. A large variation in toxicological sensitivity and no relationship between sensitivity of bats and bird or mammal test-species to pesticides could be found. In addition, bats have unique traits, such as echolocation and torpor which can be adversely affected by exposure to pesticides and which are not covered by the endpoints currently selected for wild mammal risk assessment. The current exposure assessment methodology was used for oral exposure and adapted to bats using bat-specific parameters. For oral exposure, it was concluded that for most standard risk assessment scenarios the current approach did not cover exposure of bats to pesticide residues in food. Calculations of potential dermal exposure for bats foraging during spraying operations suggest that this may be a very important exposure route. Dermal routes of exposure should be combined with inhalation and oral exposure. Based on the evidence compiled, the Panel concludes that bats are not adequately covered by the current risk assessment approach, and that there is a need to develop a bat-specific risk assessment scheme. In general, there was scarcity of data to assess the risks for bat exposed to pesticides. Recommendations for research are made, including identification of alternatives to laboratory testing of bats to assess toxicological effects.
In 2013, EFSA published a comprehensive systematic review of epidemiological studies published from 2006 to 2012 investigating the association between pesticide exposure and many health outcomes. Despite the considerable amount of epidemiological information available, the quality of much of this evidence was rather low and many limitations likely affect the results so firm conclusions cannot be drawn. Studies that do not meet the 'recognised standards' mentioned in the Regulation (EU) No 1107/2009 are thus not suited for risk assessment. In this Scientific Opinion, the EFSA Panel on Plant Protection Products and their residues (PPR Panel) was requested to assess the methodological limitations of pesticide epidemiology studies and found that poor exposure characterisation primarily defined the major limitation. Frequent use of case-control studies as opposed to prospective studies was considered another limitation. Inadequate definition or deficiencies in health outcomes need to be avoided and reporting of findings could be improved in some cases. The PPR Panel proposed recommendations on how to improve the quality and reliability of pesticide epidemiology studies to overcome these limitations and to facilitate an appropriate use for risk assessment. The Panel recommended the conduct of systematic reviews and meta-analysis, where appropriate, of pesticide observational studies as useful methodology to understand the potential hazards of pesticides, exposure scenarios and methods for assessing exposure, exposure-response characterisation and risk characterisation. Finally, the PPR Panel proposed a methodological approach to integrate and weight multiple lines of evidence, including epidemiological data, for pesticide risk assessment. Biological plausibility can contribute to establishing causation.
The EFSA Panel on Plant Protection Products and their Residues was requested to establish health-based reference values for groundwater metabolites (LM2, LM3, LM4, LM5 and LM6) of the active substance terbuthylazine based on the available evidence, unless the evidence was considered insufficient to do so. The request was accepted under the explicit circumstance that the reassessment would be made according to a different methodology than the routine methodology currently applied for the assessment of metabolites in groundwater. While for metabolites LM2, LM4 and LM5, it was concluded that the reference values for terbuthylazine are applicable, substance-specific reference values could not be derived for metabolites LM3 and LM6. The applied threshold of toxicological concern (TTC) approach has shown that metabolites LM3 and LM6 are of potential concern for consumer health, since at least one representative groundwater leaching scenario results in exposure above the relevant threshold. Moreover, other sources of exposure to LM3 and LM6 could not be excluded with certainty. It is therefore recommended to address the specific toxicities of metabolites LM3 and LM6.
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