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The SCHEER was requested to assess public health risks resulting from onshore oil and gas exploration and extraction activities on a commercial scale in the EU, and to identify knowledge gaps. Onshore oil and gas exploration and exploitation can induce increased human exposure to biocides, scale and corrosion inhibitors, oxygen scavengers, surfactants, and various hydrocarbons such as Volatile Organic Compounds (VOCs), polycyclic aromatic hydrocarbons (PAH), as well as particulate matter and noise in surrounding populations. Another consequence of onshore oil and gas exploration and exploitation relates to seismic activity: the level of evidence linking this phenomenon to onshore oil and gas exploration and extraction is moderate to strong. Some of these environmental factors are recognised carcinogens or contribute to the risk of other chronic diseases such as cardiovascular or neurological illnesses. Epidemiological studies have tried to characterise the possible impact of emissions from onshore oil and gas exploration and exploitation on human health; the vast majority of these studies are from outside the EU, generally the USA. They have relied on relatively imprecise exposure estimates, which is likely to lead to attenuation of dose-response functions. These studies indicate that the risk of haematological cancers and of preterm delivery may be higher in populations living around onshore oil and gas exploration and exploitation sites in comparison to populations living further away. The corresponding level of evidence is weak to moderate. A complete quantified risk assessment cannot be undertaken given the existing limited knowledge base but existing risk assessment studies show some coherence with the associations found in epidemiological studies. The SCHEER is surprised at the very limited scientific assessment and monitoring of both the environment and people’s health near long-established onshore oil and gas exploration and exploitation sites in the EU, given the numerous studies conducted on similar American oil and gas exploration and exploitation activities and the amount of scientific evidence pointing towards possible adverse effects of these activities. The review undertaken by the SCHEER suggests a number of knowledge gaps that could be addressed through the following actions: (i) development of a centralised and harmonised inventory of all oil and gas exploration and exploitation sites in the EU; (ii) conduct of analytical and modelling studies that identify, quantify and characterise exposure mixtures and their levels in the vicinity of these sites; (iii) initiation of targeted biomonitoring and exposure assessment studies of populations potentially at risk; (iv) implementation of large-scale epidemiological studies with accurate exposure assessment and (v) carrying out of quantitative risk assessment studies.

This Memorandum is focussed on how to use the weight of evidence approach (WoE)to conduct a risk assessment for stressors to which humans and/or the environment may be exposed. It is intended to complement the Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) report on the identification of emerging issues and the work on the challenges in future risk assessment. The aim of this document is to support the use of the WoE, wherever appropriate, for the risk assessment activities of the Scientific Committee on Health, Environmental and Emerging Risks (SCHEER). In addition, it should support the consistency in the work of different EU bodies performing risk assessments. Scientific evidence consists of observations, experimental and model results and expert judgements that serve to support, refute, or modify a scientific hypothesis or theory. The search for relevant information and data for the SCHEER comprises of identifying, collecting and selecting possible sources of evidence in order to perform a risk assessment and/or to answer the specific questions being asked. According to the issue being addressed, the SCHEER may utilise data provided by the DG tasking the SCHEER, or provided by a third party (e.g. stakeholder reports, submissions such as confidential data provided by companies or applicants), reports and Opinions of other scientific, governmental or international bodies, scientific (peer-reviewed) publications, meta-analysis and systematic reviews or personal communications. The WoE is an iterative process involving: - Problem formulation - Identification, collection and selection of the possible sources of evidence - Assessment and weighing of individual lines of evidence - Integration of lines of evidence - Description of uncertainties - Conclusion and reporting For each line of evidence, the criteria of validity, reliability and relevance need to be applied and the overall quality has to be assessed. Several tools for the analysis and description of uncertainties are presented. In the integration of the different lines of evidence, the strength of the overall evidence depends on the consistency and the quality of the results. The weighing of the total evidence should be presented in a standard format. A system is proposed that classifies results of analysis for human and environmental risks in terms of: −Strong weight of evidence: Coherent evidence from a primary line of evidence (human, animal, environment) and one or moreother lines of evidence (in particular mode/mechanistic studies) in the absence of conflicting evidence from one of the other lines of evidence (no important data gaps) −Moderate weight of evidence: good evidence from a primary line of evidence but evidence from several other lines is missing (important data gaps) −Weak weight of evidence: weak evidence from the primary lines of evidence (severe data gaps) −Uncertain weight of evidence: due to conflicting information from different lines of evidence that cannot be explained in scientific terms −Weighing of evidence not possible: No suitable evidence available

We describe a material of 577 infants born of epileptic women treated with anticonvulsants in monotherapy during early pregnancy and collected from France, Italy, and Sweden. The incidence of major malformations is increased compared with the general population but no definite difference in risk can be demonstrated between the various anticonvulsants, but valproic acid was associated with a doubling of the average risk. The increased risk for facial clefts and for cardiac malformations, described from most studies on epilepsy during pregnancy, cannot be seen in this material. Unusually many cases of penis abnormalities (micropenis, hypospadias) were noted. An effect on fetal growth can be demonstrated and is apparently more pronounced for carbamazepine than for the other drugs. It results in a reduced birth weight in spite of normal gestational length, reduced body length and head circumference. The possible biological significance of this finding is discussed.