5.5 Pesticide and Metabolites Residues in Honeybees: A 2014-2017 Greek Compendium

In the period between 2014 mid-2017, more than 200 samples of honeybees were sent by authorities and individuals in Benaki Phytopathological Institute after incidents of unexpected deaths of bees in various parts of Greece. The samples were analyzed for pesticides and breakdown products, by two multi-residue methods based on an expanded HPLC-ESI-MS/MS and a newly developed GC-MS/MS method. Sample preparation was optimized and based on modified QuEChERS using for clean-up C18 and PSA. Until mid-2017, 293 detections were registered in a total of 205 honeybee samples, resulting in a 76% percent of positive samples, to at least one active substance. Concentrations’ range varied from 1 to 160000 ng/g bee body weight . In some cases, these levels surpassed LD50 values indicating intoxication events. Predominant substances were clothianidin, coumaphos, imidacloprid, acetamiprid and dimethoate. In less extent, other acaricides such as amitraz (mostly its breakdown products DMF, DMPF), tau-fluvalinate and certain pyrethroids exemplified by cyhalothrin, cypermethrin and deltamethrin were also recorded. In several samples, more than one active substance was detected.Overall, this work aspires to provide valuable insight to pesticides and metabolites occurrence in honeybees in Greece between 2014-2017 and in parallel assist research community and apiculturists in this pivotal Mediterranean region that bee health and pollination services have prolific importance.In the period between 2014 mid-2017, more than 200 samples of honeybees were sent by authorities and individuals in Benaki Phytopathological Institute after incidents of unexpected deaths of bees in various parts of Greece. The samples were analyzed for pesticides and breakdown products, by two multi-residue methods based on an expanded HPLC-ESI-MS/MS and a newly developed GC-MS/MS method. Sample preparation was optimized and based on modified QuEChERS using for clean-up C18 and PSA. Until mid-2017, 293 detections were registered in a total of 205 honeybee samples, resulting in a 76% percent of positive samples, to at least one active substance. Concentrations’ range varied from 1 to 160000 ng/g bee body weight . In some cases, these levels surpassed LD50 values indicating intoxication events. Predominant substances were clothianidin, coumaphos, imidacloprid, acetamiprid and dimethoate. In less extent, other acaricides such as amitraz (mostly its breakdown products DMF, DMPF), tau-fluvalinate and certain pyrethroids exemplified by cyhalothrin, cypermethrin and deltamethrin were also recorded. In several samples, more than one active substance was detected.Overall, this work aspires to provide valuable insight to pesticides and metabolites occurrence in honeybees in Greece between 2014-2017 and in parallel assist research community and apiculturists in this pivotal Mediterranean region that bee health and pollination services have prolific importance

Headspace Solid Phase Micro Extraction Gas Chromatographic Determination of Fenthion in Human Serum

A simple and effective analytical procedure was developed for the determination of fenthion residues in human serum samples. The sample treatment was performed using the headspace solid-phase micro extraction with polyacrylate fiber, which has the advantage to require low amount of serum (1 mL) without tedious pre-treatment. The quantification of fenthion was carried out by gas chromatography-mass spectrometry and the recoveries ranged from 79 to 104% at two spiking levels for 6 replicates. Detection and quantification limits were calculated as 1.51 and 4.54 ng/mL of serum respectively. Two fenthion metabolites fenoxon and fenthion–sulfoxide were also identified

Guidance on dermal absorption

This guidance on the assessment of dermal absorption has been developed to assist notifiers, users of test facilities and Member State authorities on critical aspects related to the setting of dermal absorption values to be used in risk assessments of active substances in Plant Protection Products (PPPs). It is based on the ‘scientific opinion on the science behind the revision of the guidance document on dermal absorption’ issued in 2011 by the EFSA Panel on Plant Protection Products and their Residues (PPR). The guidance refers to the EFSA PPR opinion in many instances. In addition, the first version of this guidance, issued in 2012 by the EFSA PPR Panel, has been revised in 2017 on the basis of new available data on human in vitro dermal absorption for PPPs and wherever clarifications were needed. Basic details of experimental design, available in the respective test guidelines and accompanying guidance for the conduct of studies, have not been addressed but recommendations specific to performing and interpreting dermal absorption studies with PPPs are given. Issues discussed include a brief description of the skin and its properties affecting dermal absorption. To facilitate use of the guidance, flow charts are included. Guidance is also provided, for example, when there are no data on dermal absorption for the product under evaluation. Elements for a tiered approach are presented including use of default values, data on closely related products, in vitro studies with human skin (regarded to provide the best estimate), data from experimental animals (rats) in vitro and in vivo, and the so called ‘triple pack’ approach. Various elements of study design and reporting that reduce experimental variation and aid consistent interpretation are presented. A proposal for reporting data for assessment reports is also provided. The issue of nanoparticles in PPPs is not addressed. Data from volunteer studies have not been discussed since their use is not allowed in EU for risk assessment of PPPs

Draft for internal testing Scientific Committee guidance on appraising and integrating evidence from epidemiological studies for use in EFSA's scientific assessments.

EFSA requested its Scientific Committee to prepare a guidance document on appraising and integrating evidence from epidemiological studies for use in EFSA's scientific assessments. The guidance document provides an introduction to epidemiological studies and illustrates the typical biases of the different epidemiological study designs. It describes key epidemiological concepts relevant for evidence appraisal. Regarding study reliability, measures of association, exposure assessment, statistical inferences, systematic error and effect modification are explained. Regarding study relevance, the guidance describes the concept of external validity. The principles of appraising epidemiological studies are illustrated, and an overview of Risk of Bias (RoB) tools is given. A decision tree is developed to assist in the selection of the appropriate Risk of Bias tool, depending on study question, population and design. The customisation of the study appraisal process is explained, detailing the use of RoB tools and assessing the risk of bias in the body of evidence. Several examples of appraising experimental and observational studies using a Risk of Bias tool are annexed to the document to illustrate the application of the approach. This document constitutes a draft that will be applied in EFSA's assessments during a 1-year pilot phase and be revised and complemented as necessary. Before finalisation of the document, a public consultation will be launched

Re-evaluation of the existing health-based guidance values for copper and exposure assessment from all sources

Copper is an essential micronutrient and also a regulated product used in organic and in conventional farming pest management. Both deficiency and excessive exposure to copper can have adverse health effects. In this Scientific Opinion, the EFSA 2021 harmonised approach for establishing health-based guidance values (HBGVs) for substances that are regulated products and also nutrients was used to resolve the divergent existing HBGVs for copper. The tightly regulated homeostasis prevents toxicity manifestation in the short term, but the development of chronic copper toxicity is dependent on copper homeostasis and its tissue retention. Evidence from Wilson disease suggests that hepatic retention is indicative of potential future and possibly sudden onset of copper toxicity under conditions of continuous intake. Hence, emphasis was placed on copper retention as an early marker of potential adverse effects. The relationships between (a) chronic copper exposure and its retention in the body, particularly the liver, and (b) hepatic copper concentrations and evidence of toxicity were examined. The Scientific Committee (SC) concludes that no retention of copper is expected to occur with intake of 5 mg/day and established an Acceptable Daily Intake (ADI) of 0.07 mg/kg bw. A refined dietary exposure assessment was performed, assessing contribution from dietary and non-dietary sources. Background copper levels are a significant source of copper. The contribution of copper from its use as plant protection product (PPP), food and feed additives or fertilisers is negligible. The use of copper in fertilisers or PPPs contributes to copper accumulation in soil. Infant formula and follow-on formula are important contributors to dietary exposure of copper in infants and toddlers. Contribution from non-oral sources is negligible. Dietary exposure to total copper does not exceed the HBGV in adolescents, adults, elderly and the very elderly. Neither hepatic copper retention nor adverse effects are expected to occur from the estimated copper exposure in children due to higher nutrient requirements related to growth

Guidance on aneugenicity assessment

The EFSA Scientific Committee was asked to provide guidance on the most appropriate in vivo tests to follow up on positive in vitro results for aneugenicity, and on the approach to risk assessment for substances that are aneugenic but not clastogenic nor causing gene mutations. The Scientific Committee confirmed that the preferred approach is to perform an in vivo mammalian erythrocyte micronucleus test with a relevant route of administration. If this is positive, it demonstrates that the substance is aneugenic in vivo. A negative result with evidence that the bone marrow is exposed to the test substance supports a conclusion that aneugenic activity is not expressed in vivo. If there is no evidence of exposure to the bone marrow, a negative result is viewed as inconclusive and further studies are required. The liver micronucleus assay, even though not yet fully validated, can provide supporting information for substances that are aneugenic following metabolic activation. The gastrointestinal micronucleus test, conversely, to be further developed, may help to assess aneugenic potential at the initial site of contact for substances that are aneugenic in vitro without metabolic activation. Based on the evidence in relation to mechanisms of aneugenicity, the Scientific Committee concluded that, in principle, health-based guidance values can be established for substances that are aneugenic but not clastogenic nor causing gene mutations, provided that a comprehensive toxicological database is available. For situations in which the toxicological database is not sufficient to establish health-based guidance values, some approaches to risk assessment are proposed. The Scientific Committee recommends further development of the gastrointestinal micronucleus test, and research to improve the understanding of aneugenicity to support risk assessment

Scientific Opinion about the Guidance of the Chemical Regulation Directorate (UK) on how aged sorption studies for pesticides should be conducted, analysed and used in regulatory assessments

Abstract The EFSA Panel on Plant Protection Products and their Residues reviewed the guidance on how aged sorption studies for pesticides should be conducted, analysed and used in regulatory assessment. The inclusion of aged sorption is a higher tier in the groundwater leaching assessment. The Panel based its review on a test with three substances taken from a data set provided by the European Crop Protection Association. Particular points of attention were the quality of the data provided, the proposed fitting procedure of aged sorption experiments and the proposed method for combining results obtained from aged sorption studies and lower‐tier studies on degradation and adsorption. Aged sorption was a relevant process in all cases studied. The test revealed that the guidance could generally be well applied and resulted in robust and plausible results. The Panel considers the guidance suitable for use in the groundwater leaching assessment after the recommendations in this Scientific Opinion have been implemented, with the exception of the use of field data to derive aged sorption parameters. The Panel noted that the draft guidance could only be used by experienced users because there is no software tool that fully supports the work flow in the guidance document. It is therefore recommended that a user‐friendly software tool be developed. Aged sorption lowered the predicted concentration in groundwater. However, because aged sorption experiments may be conducted in different soils than lower‐tier degradation and adsorption experiments, it cannot be guaranteed that the higher tier predicts lower concentrations than the lower tier, while lower tiers should be more conservative than higher tiers. To mitigate this problem, the Panel recommends using all available higher‐ and lower‐tier data in the leaching assessment. The Panel further recommends that aged sorption parameters for metabolites be derived only from metabolite‐dosed studies. The formation fraction can be derived from parent‐dosed degradation studies, provided that the parent and metabolite are fitted with the best‐fit model, which is the double first‐order in parallel model in the case of aged sorption