few labs had capabilities to analyze minute concentrations. Meaning that they had to be processed at the ppb (parts per billion) and ppt (parts per trillion) level. This is a very labor-intensive activity and one highly susceptible to cross-contamination. For example, once a lab technician was simply wearing a bug repellent when processing a sample. The repellent, DEET, got into the sample and destroyed the test.

 

ENDOCRINE DISRUPTERS

      Of the substances called emerging contaminants a major concern has been with a special subset: those substances that affect the endocrine system in animals and humans and may be the cause of Intersex. The endocrine system is made up of 1. Glands located throughout the body of mammals, birds and fish, 2. Hormones that are made by these glands, and 3. Receptors that respond to these hormones. Endocrine disruptors are substances that disturb this system and cause reproductive and other metabolic problems. Some of the chemicals that are being studied mimic a natural hormone or cause it to respond at inappropriate times. Others block the positive effect of hormones. Still others can cause an overproduction or underproduction of a hormone.

      One example of the devastating consequences of the exposure of animals--including humans--to an endocrine disruptor is the case of the potent drug diethylstilbestrol (DES) a synthetic estrogen.  Prior to its ban in the early 1970’s doctors found that it affected the development of the human reproductive system and caused vaginal cancer.

 

WHAT CAN CITIZENS DO?

     Finally, it must be noted we citizens are adding to industrial and agriculture pollution– generally thought to be the main culprits—by our naiveté on this subject. But one example: Don’t dispose of outdated and unused pills by throwing them down the toilet. It is now known that this action allows them to enter groundwater and other water bodies. Not only are pharmaceuticals—both prescription and over-the-counter—taken by humans more powerful than most people realize, many do not lose their effectiveness as quickly as once thought. Also, a significant percentage of many pills are never “used” by the body and are passed into the waste stream. This amount is extremely variable in medications. However, some people only use as little as 5% of a drug. (For more ideas on what citizens can do go to "Wise Consumer Section)     

 

FINAL THOUGHT

    On the horizon is the major study being done for the United States Geological Service by Vickie Blazer and Doug Chambers. It can be hoped that some answer as to what is causing this problem will be forthcoming soon. Then we will need to develope an answer to getting rid of the problem.

 

 

 

 

     Jane Goodall, respected scientist and popular author, in her book “The Ten Trusts” has challenged citizens to do something about protecting people, animals and the environment. She warns: “We in the industrialized nations have some fifty chemicals in our bodies that were not there half a century ago.

      Should we humans worry? Obviously the use of chemicals is changing body chemistry. In most studies scientists note that while the negative effects of contaminants on animals and the environment are known, a complete picture of the negative effects of emerging contaminants on humans has yet to be determined. Yet every thinking person should be concerned about contaminants.

     It is the study of emerging contaminants and endocrine disrupters that is the subject of this web site which specifically focuses on the Potomac River Watershed. It is in the Potomac and it tributaries where there have been numerous fish kills in which some fish have abnormal sores and many have a condition known as Intersex. Intersex occurs when males show signs of feminization. Currently scientific thinking places emphasis on a combination of conditions and factors - both natural and chemical substances plus stress - as possible causes. How dying fish, fish with lesions, and endocrine disruptions are related is complicated and the relationship between these three conditions is not known. 

 

EMERGING CONTAMINANTS IN WATER

      In a 2002 publication, Environmental Science & Technology reasoned this way, “…protecting the integrity of our water resources is one of the most essential environmental issues of the 21^st century.” The article goes on to pinpoint industrial byproducts, pharmaceutical, household and agricultural chemicals as substances of concern. Many of these substances, as well as others, are referred to as emerging contaminants. However, emerging contaminants in the scientific world are taking their time emerging, or can we can we say, being identified, analyzed and quantified. For over 20 years government agencies – USGS, EPA and others – have been evaluating a group of man-made organic compounds, plus some natural substances, such as Arsenic, that appear to cause adverse effects in humans and the environment. But finally, emerging contaminants are hiding no longer.

     Pharmaceuticals, hormones and other organic contaminants in streams were exposed in a story, “Drinking Water Drugged” that appeared in an April 2006 issue of Discover Magazine. This short article declared the subject of emerging contaminants one of the top 100 Science Stories of the past five years. One of the studies cited as significant was the USGS paper “Pharmaceuticals, Hormones and Other Organic Wastewater contaminants in US Streams, 1999-2000: A National Reconnaissance. This “National Reconnaissance” used analytical methods to measure concentrations of 95 organic wastewater contaminants in water samples taken from a network of 139 streams across 30 states.

These substances were found in 80% of the streams sampled, all of which were downstream of intense urbanization or livestock production. A characteristic of the contaminants studied was that they affect changes at very low concentrations in water. This is why they have been called “emerging” because until recently very