What's In The Water?

2 April 2009

by Peter L. deFur, Ph.D.

It’s been about 15 years since scientists found male fish that looked like females and began to investigate the nature of this problem. Research scientists in England (John Sumpter and colleagues) and then in the US (Leroy Folmar and colleagues), found male fish that not only looked female, but were producing egg proteins normally produced only by female fish during spawning season. The fish were collected downstream from sewage treatment plants and the hunt was on for what was coming out of the end of the pipes to give male fish the female characteristics. It turned out that three different types of chemicals could be responsible: naturally occurring hormones, birth control pills and industrial chemicals. All were present and able to “feminize” male fish, based on data collected from wild caught fish and from field and lab experiments.

Shortly after these reports, the US Geological Survey geared up to sample water from 139 streams to assess the range of chemicals coming out of the pipes and into our nation’s water. In 2002, USGS reported that our waterways contain dozens of hormones, over the counter drugs, prescription drugs, industrial chemicals, pesticides and even chemicals that were banned many years ago. For the past seven years, government agencies and scientific researchers have been reporting that our rivers, streams, coastal bays and estuaries carry a wide array of chemicals discharged from sewage treatment plants, industrial facilities, farm ponds and washing off yards, farms and city streets. This cannot be good news, and it is not.

Now let’s admit that not all chemicals can be found in all streams, and many chemicals turn up at low levels. But these chemicals present real problems and there are good reasons to get busy cleaning up what comes out of the end of the pipes, and off the yards, farms and city streets. Estrogens that are naturally excreted combine with prescription estrogenic hormones, pesticides and industrial estrogenic chemicals. The matter of intersex fish is serious and can lead to all sorts of problems, from reproductive failures to diseases. The same chemical mixtures are likely causing other problems with aquatic animals, from suppressing immune systems to killing fish eggs and young fish.

Scientists do not know exactly what most of the chemicals reported by USGS do to most of the animals found in our nation’s waters. How does Prozac affect oysters, clams or shrimp? The combination of dozens of chemicals, or even just a few may prove fatal to the small animals on which all others depend for food. We do know for certain that artificial chemicals will disrupt normal hormone function with serious consequences for birds, mammals, fish, reptiles, shrimp, snails, crabs, and other animals.

In light of the knowledge of what harm might come to us and other animals, and the large number of chemicals discharged into our nation’s waters, it is time we cleaned up the waters. Discharges and run-off of all these chemicals needs to decline and end so that the waters will again run clear.