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Synthetic Hormonal Use in Humans and Emerging Risks to the Environment


We are just beginning to realize the long-term adverse physiological and psychological effects for human users of synthetic hormones, their welfare, and the ecological safety of our environment and drinking water due to the survival of their metabolites through our bodies and through our waste water treatment facilities.  Emerging risks are being discovered and evaluated.

The US Environmental Protection Agency (EPA) has identified research needs to determine future risks of synthetic estrogen metabolites in our environment, such as those from ethinyl estradiol, and other endocrine-disrupting chemicals (EDCs).  The EPA would like studies to determine the effects of EDCs on reproductive, neurological, and immunological function, as well as carcinogenesis. 

The White House’s Committee on the Environment and Natural Resources increased their budget to include studies in these areas on EDCs. 

The US Congress added provisions to the Food Quality Protection Act (FQPA) and the Safe Drinking Water Act of 1996 to require testing for estrogenicity and other hormonal activity. 

The Endocrine Disruptor Screening and Testing Advisory Committee (EDSTAC) was established in 1998 as part of the Toxic Substances Control Act.  The study of EDCs has become one of the biggest testing programs ever in the history of toxicology.[1]

The persistence of pharmaceutical contaminants in our aquatic environment may be partially attributed to human consumption of drugs and subsequent discharges from sewage treatment plants. 

The contamination of our water resources by pharmaceuticals and their metabolites, particularly the EDCs, is emerging as an international environmental concern.  The long-term effects of human exposure to continuous low-level EDCs are not yet well understood.[2]

The University of California Berkeley collected samples of EDCs at the Sweetwater Groundwater Recharge Facility, located in Tuscon, Arizona. 

Influent concentrations of 17-α estradiol (a metabolite of ethinyl estradiol) were approximately 2ng/L.  After passage through the treatment wetland 0.5ng/L of 17-α estradiol still remained.  Because 17-α estradiol is resistant to biotransformation in the activated sludge treatment systems the researchers hypothesized that the observed biotransformation must be attributed to some other process, such as indirect photolysis.  Nevertheless, a measurable amount of the ethinyl estradiol metabolite remained after passage through the water treatment facility.[3]

Many researches have been able to correlate endocrine system anomalies due to contaminants of EDCs. 

There are a few researchers who have documented examples of aberrant animal behavior and disruptions of their reproductive patterns due to EDCs in their habitat:  gulls from Lake Ontario and southern California[4]; alligators in Lake Apopka, FL[5]; dolphins in the Mediterranean Sea; and fresh-water fish[6].

Tuscon, AZ is a popular location for toxicologists to study.  Because of the aridity of the region water managers may incorporate wetlands into sequential wastewater treatments leading to potable reuse of reclaimed water. 

The University of Arizona in Tuscon has studied the Constructed Ecosystems Research Facility (CERF) located in Tuscon.  During the summer months evaporation (evapotranspiration) water losses are 20-50%.  This leads to a maintenance of estrogenic contaminants and their removal efficacy being inversely related to temperature.[7]

David Quanrud et al have done some very interesting theoretical work by isolating one of the human estrogen receptors to determine how significant our exposure is to these detectable estrogenic contaminants. 

The contaminants of ethinyl estradiol metabolites that are passed through human urine and through waste water treatment plants are showing to be of high enough concentrations to remove natural human estrogen from their receptors due to a displacement by the estrogenic contaminants found in the Constructed Ecosystems Research Facility. 

These studies are called competitive binding assays and involve only isolated human receptors.  Therefore no hard evidence can yet be drawn from these studies in their relation to whole organism toxicity.  Work is underway at establishing correlations between these binding assays and more physiological relevant bioassays to determine whole organism toxicity.[8]

[1] Daston, George P. Toxicological Sciences. 74(2):245-252, August 2003.

[2] Boyd, Glen R., Grimm, Deborah A. Occurrence of Pharmaceutical Contaminants and Screening of Treatment Alternatives for Shoutheastern Louisiana.  Annals of the New York Academy of Sciences. 948:80-89, 2001.

[3] Sedlak, David L., Pinkston, Karen E  Factors Affecting the Concentration of Pharmaceuticals Released to the Aquatic Environment.  Department of Civil and Environmental Engineering, University of California Berkeley.  Presented at the 2nd International Conference on Pharmaceuticals and Endocrine Disrupting Chemicals in Water, Minneapolis, MN, October 9-11. 2001.

[4] Colbourn, T. Dumanoski, D., and Myers, J.P. (1996) Our Stolen Future. Penguin Books, New York.

[5] Roefer, P., Snyder, S., Zegers, R.E., Rexing, D.J., and Fronk, J.L. 2000 Endocrine disrupting chemicals in a source water. Journal of the American Water Works Association, 92(8):52-58.

[6]Tyler,C.R., Jobling,S., and Sumpter,J.P. 1998. Endocrine disruption in wildlife: a critical review of the evidence.  Critical Reviews in Toxicology, 28(4):319-361.

[7] Ibid.

[8] Ibid.
[18 Jan 2010, PharmFacts E-News Update, Neil Noesen, PharmD, ] 





In 2006, the U.S. Geological Survey performed a study in the Potomac River and found that 80 percent of the male smallmouth bass had intersex characteristics — these male fish were growing female reproductive parts. (See the Potomac Conservancy's web site, for more information.)

This reality is also contaminating our municipal water supply and posing hazards to anyone who drinks it.

In New Jersey, traces of birth control hormones and other prescription drugs were found in municipal tap water in 2003.