Bridging the gap between academic research and regulatory health risk assessment of Endocrine Disrupting Chemicals Anna Beronius 1 , Annika Hanberg 2 , Johanna Zilliacus 2 and Christina Rude´n 1 Regulatory risk assessment is traditionally based primarily on toxicity studies conducted according to standardized and internationally validated test guidelines. However, health risk assessment of endocrine disrupting chemicals (EDCs) is argued to rely on the efficient integration of findings from academic research. The aim of this review was to provide an overview of current developments to facilitate the use of academic research in regulatory risk assessment of chemicals and how certain aspects of study design and reporting are particularly important for the risk assessment process. By bridging the gap between academic research and regulatory health risk assessment of EDCs, scientific uncertainty in risk assessment conclusions can be reduced, allowing for better targeted policy decisions for chemical risk reduction. Addresses 1 Department of Applied Environmental Science, Stockholm University, 106 91 Stockholm, Sweden 2 Institute of Environmental Medicine, Karolinska Institutet, PO Box 210, 171 77 Stockholm, Sweden Corresponding author: Beronius, Anna (anna.beronius@itm.su.se) Current Opinion in Pharmacology 2014, 19:99–104 This review comes from a themed issue on Endocrine and metabolic diseases Edited by Scott M Belcher http://dx.doi.org/10.1016/j.coph.2014.08.005 1471-4892/# 2014 Elsevier Ltd. Introduction Regulatory risk assessment of chemicals is conducted for the purpose of protecting human health and the environ- ment against the negative effects of hazardous chemicals. It is carried out as basis for decisions on approving, restricting or phasing out the use of chemicals (Figure 1). As such, it is important that the scientific data on which the risk assessment, and consequently regulat- ory decision making, is to be based are reliable and relevant for this purpose. The evaluation of toxicity data is thus an integral and critical part of the regulatory process. Guidance documents for risk assessment of chemicals issued by different authorities and organizations generally require or recommend that all relevant toxicity data should be considered in the risk assessment process [1– 5]. However, toxicity studies conducted in accordance with standardized and internationally validated test guidelines, such as the Organisation for Economic Co- operation and Development (OECD) test guidelines, and Good Laboratory Practices (GLP) have often been pre- ferred in regulatory health risk assessment. Test guide- lines provide standardized requirements as well as recommendations for the design, performance and, to some extent, the reporting of toxicity studies and have been implemented to ensure the reliability of results. The major advantages of using standardized test methods are that the results are directly comparable across sub- stances and that the data they generate will be accepted across jurisdictions. The major disadvantage is that stan- dard methods do not always represent the most relevant testing approach and cannot cover all relevant adverse endpoints given the substance under investigation. Avail- able standardized methods are, for example, criticized for being inadequate when it comes to identifying and eval- uating endocrine disrupting chemicals (EDCs), e.g. for not including the most sensitive endpoints or covering sensi- tive windows of exposure [6  ,7,8,9  ,10,11]. The aim of GLP is to ensure the quality of the laboratory practices by specifying standard operational laboratory procedures and extensive requirements for data reporting. Notably, neither standardized test guidelines nor GLP will auto- matically ensure the relevance of a study for the health risk assessment purpose in question. The importance of reducing the potential risks to human health, as well as to the environment, posed by EDCs have been highlighted in several recent reports and is high on the political agenda [8,12,13]. A number of standardized in vitro and in vivo test guidelines have been enhanced or developed by the OECD [14] as well as by the US Environmental Protection Agency (EPA) [15] for the detection and characterization of some types of EDCs, primarily substances interacting with estrogen, androgen, and thyroid hormone signaling pathways. But for many other endocrine pathways standardized methods are still lacking and a common and comprehensive strategy for regulatory identification and risk assessment of EDCs remains to be implemented. Available online at www.sciencedirect.com ScienceDirect www.sciencedirect.com Current Opinion in Pharmacology 2014, 19:99–104