We've all heard about the adverse effect the aging baby-boomers are having on social security - but you may not have heard about their effect on our waters! An article in NRDC's On Earth points out that an aging population is drastically increasing the number of drugs prescribed each year and Americans already fill more than three billion prescriptions annually. Although these substances are good for our health, up to 90% of these drugs can leave our bodies unchanged. These endocrine disrupting compounds are then discharged to local rivers via sewage discharge. Other sources of these compounds include veterinary use and flushing of unused drugs down the toilet.

Not surprisingly, the U.S. Geological Survey has found organic chemicals including pharmaceuticals at low levels in streams across the country and determined that wastewater treatment plants are a significant source of contaminants such as antibiotics. These drugs are now making a recognized mark on aquatic life. Pharmaceuticals and other endocrine disruptors from wastewater have been shown to cause "intersex" fish in Colorado. In the Potomac and Shenandoah Rivers endocrine disruptors are also the suspected cause of intersex fish.

It is unclear that these compounds have an effect on human health via drinking water, but as Potomac Riverkeeper Ed Merrifield pointed out in his testimony to the House Government Reform Committee in 2006, these fish are canaries in the coal mine and we just don't know how low levels of these chemicals could effect human health. I'd have to agree that given the gender-bending power of pharmaceuticals on fish, seems like reduction and removal of pharmaceuticals in our water supply is a wise idea. Current treatment requirements, however, don't remove pharmaceuticals, although research has shown that advanced processes, like reverse osmosis, can remove most of these contaminants.