State of the Science of Endocrine Disruptors

(International Programme on Chemical Safety 2002). Over the past decade there have been significant advances in our understanding of endocrine disrupting chemicals (EDCs): their numbers, mechanisms of action, biological effects, and impacts on human and wildlife health. First, as described in the new report (WHO/UNEP 2013), the convergence of wildlife, laboratory animal, and epidemiology data suggests a greater role for EDCs in disease, even more than was predicted just 10 years ago. Taking the animal and human evidence together, the report demonstrates a strong likelihood that exposure to EDCs during fetal life and/or puberty plays a role in the proliferation of male and female reproductive problems, endocrine-related cancers, infections , asthma, obesity, diabetes, and behavioral and learning disorders, including attention deficit/hyperactivity disorder (ADHD). The incidences of these conditions have increased significantly not only in the United States but across the globe. Because genes do not change fast enough to explain this increase, environ mental causes must be involved. The environmental contribution to disease is estimated to be 24–33% of the global disease burden (Smith et al. 1999). Although it is challenging to address the role of the environ ment in disease, there is also a tremendous opportunity to improve human health by identifying environ mental elements that affect public health. The recognition of these challenges and opportunities, along with the fact that many diseases are associated with the endocrine system (e.g., infertility, diabetes, breast and prostate cancer) has led to the focus on EDCs. Second, it is now accepted that development (in utero and the first years of life) is a very sensitive time for EDC-induced health effects (Kortenkamp et al. 2011). Over the last 10 years, the focus of EDC research has shifted from investigating adult exposure and disease outcomes to examining develop mental exposure and later-life disease outcomes. This latter approach is now considered the most appropriate approach for most endocrine-related diseases/disorders (U.S. Environmental Protection Agency 2012). Third, identifying those chemicals with endocrine activity from all the chemicals used and released worldwide is a major challenge, and we are likely assessing only the " tip of the iceberg. " Hundreds of chemicals, as well as persistent organic pollutants, have been identified as EDCs. EDCs are not uniform: They have very different properties, sources, and fates in the environment. Although it may be possible to trace high production volume chemicals, numerous additives and process chemicals are not traceable. Adding …