ENDOCRINE DISRUPTOR UPDATE

February 8, 2008 

Due to increasing public health concerns in the mid-1990’s, the U.S. Environmental Protection Agency (EPA) Office of Research and Development (ORD) initiated a research program to address scientific questions related to endocrine disrupting chemicals (EDCs).  Many of these EDCs are pharmeatucals, or precscription drugs.  These questions let to a 1996 legislated mandate requiring the EPA to develop a screening a testing program to identify chemicals having the potential to disrupt hormonal activity in humans and wildlife (i.e., EDCs).   

Some EDCs already well known and regulated include DDT (pesticides), pthalates and bisphenol A (plasticizers), and highly chlorinated compounds such as PCBs, dioxin, and furan.  The screening and testing program will identify lesser known EDCs and “emerging” pollutants of concern that may exist in the environment in low concentrations (less than 1 part per billion).  These pollutants range from hormones and steroids found in pharmaceuticals to chemicals used in personal care products and antibiotics used in animal feed operations.

 ORD published a Research Plan for ODCS (EPA link) in 1998.  In 1999, ORD published the first of four iterations of its Multi-Year Plan (MYP) for Endocrine Disruptors with the latest edition drafted in August 2007.  The MYP identified three long-term goals (LTG):  LTG 1 develops low-dose response curves among other things in order to provide “…a better understanding of the science underlying the effects, exposure, assessment, and management of endocrine disruptors”.  LTG 2 will determine “…the extent of the impact of endocrine disruptors on humans, wildlife, and the environment.”  LTG 3 will support “…EPA’s screening and testing program”.

 Wastewater treatment plant (WWTP) effluent has been targeted as a possible source of EDCs in our waterways, and concern has been expressed relative to human exposure to EDCs in our drinking water sources.  It is important to note, that while the evaluation of drinking water sources and WWTPs as potential sources of human and wildlife exposure to EDCs has been included in the MYPs, there is no conclusive evidence to-date linking these sources to endocrine disruption in humans.  In addition, it has been determined that WWTP processes remove greater than 90% of most known EDCs.

 EPA began dozens of different research projects as early as 2001 to reach the three LTGs, and many results have already been reported (EPA link).  All three goals are expected to be reached by the year 2013. 

WERF’s 2005 “Technical Brief: Endocrine Disrupting Compounds and Implications for Wastewater Treatment” indicates that “…the effects observed in fish and other aquatic organisms downstream of wastewater treatment plants…can also have other causes, such as changes in temperature…[or] represent natural variation in a population”.  If asked by the public if your WWTP effluent has an effect on humans due to EDCs, using WERF’s recommended answer is to not simply say “yes”, but rather state:  “The data collected to date indicate that the effect is not occurring and, based on those studies, we do not expect it to occur”.