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Pollutant Soup

What has been the biggest surprise in your life as a scientist?
vom Saal: “How much fun it is to be able to follow new leads into entirely new areas of science.”

Read Frederick vom Saal's
full Q&A

Tillitt: “The fact that science and the associated information were not the most important factors in the development and execution of environmental regulations about pollution.”

Read Donald E. Tillitt's
full Q&A »

Hester: “The humility in realizing the vast amount we don't understand, the joy in learning a little piece, and the satisfaction when that little piece makes a difference.”

Read Michelle Hester's
full Q&A »

Developmental biologist Fredrick vom Saal from the University of Missouri, Columbia, and environmental toxicologist Don Tillett from the U.S. Geological Survey are searching for aquatic gender-benders. Throughout America’s waters, animals with mysterious abnormalities are turning up—from male fish producing eggs in their testes to amphibians with developmental disorders.  What is the cause?

Possible suspects include chemicals from pharmaceuticals, cosmetics, pesticides, fertilizers, food additives, industrial wastes and more. One of the most ubiquitous suspects, however, leaches from commonly used plastics—
bisphenol A. More than seven billion tons of this chemical is produced globally. And once it enters the water, animals, including ourselves, can readily ingest and absorb it. According to vom Saal’s studies, doses as small as parts per trillion can have an impact.

A 2005 U.S. Center for Disease Control study reported that 95 percent of tested Americans contained bisphenol A at levels known to cause abnormalities in lab animals. This compound, which mimics the female hormone estrogen, can disrupt an animal’s endocrine system and, even in tiny amounts, scramble early cell development in mice and other lab animals. “Too much of any hormone at the wrong moment can be risky,” explains vom Saal. Lacing any animal system with it can have consequences. As vom Saal relates, “You have essentially set a time bomb in the genes of that animal.”

More than 30,000 chemicals are used commercially in the United States and Canada, but only a small portion is regulated for impacts on the environment and humans. Furthermore, these chemicals are typically tested individually; combined, they can be even more potent. The U.S. Environmental Protection Agency recognizes the problem and has asked major chemical manufacturers to test retroactively 3,000 of the most widely distributed chemicals, albeit voluntarily. This task has yet to be completed.

Chemicals aren’t the only pollution problem in our waters. Discarded marine debris like
ghost nets
and fishing lines can capture and strangle wildlife. Animals can mistake ocean trash for food, and in the case of long-lasting plastic, this behavior is of major concern. Fish, seabirds, turtles and cetaceans frequently consume round plastic pellets that resemble fish eggs and plastic bags they assume are jellyfish, often leading to fatal consequences.

Biologist Michelle Hester, president of the environmental nonprofit, Oikonos, tracks majestic albatrosses flying across the North Pacific. She, biologist David Hyrenbach and their colleagues have witnessed firsthand the horrifying results of this deadly smorgasbord in the stomachs of dead albatross chicks. According to Hester, the chicks’ bellies become so full of trash, “there’s no room for food.” Hester is even more shocked that such refuse is from multiple feedings. “These very experienced albatross parents, which can live for 60 years, repeatedly mistake plastic as a source of food and funnel it directly into their chicks."

By tagging and tracking adult birds, Hester, Hyrenbach and their colleagues have found that albatross feed their chicks with debris gathered from an area in the Pacific Ocean called the North Pacific Gyre. Within the Gyre, swirling currents collect miles of trash into what is now known as the
Garbage Patch. Captain Charles Moore of the Algalita Foundation also surveys these pollution-filled eddies. He has found that some water samples have “less plankton than plastic," says Moore. "The ocean has become a plastic soup.”

While the amount of plastic in our world may seem overwhelming, we can all make a dent in its destructive powers by first stopping trash from getting into our water systems. For more on plastic pollution and what you can do to reduce it, view the Charles Moore video and follow these guidelines:

  • Avoid unnecessary use of plastics. Bring your own cloth bags to the store when you go shopping. Right now other nations and cities across the United States are banning the use of plastic bags. Join the effort.
  • When buying plastic products, stick to those that are more easily recycled. Numbers 1 and 2 are the best. See the Strange Days Smart Plastics Guide (English | Spanish) for more details.   [PDF file]
  • Participate in river, stream or beach cleanups.
  • Join the Strange Days Plastics Cause. Off-site Link
  • Support policies that encourage industry and treatment facilities to filter out dangerous chemicals from our wastewater and reduce excess use of plastics.

For more exciting solutions go to: What Can We Do?


Vom Saal, F.S and C. Hughes. (2005). An extensive new literature concerning low-dose effects of bisphenol A shows the need for a new risk assessment,
Environmental Health Perspectives, Off-site Link113(8): 926-933.


Donn, J. and Mendoza, M. (March 10, 2008) AP Probe Finds Drugs in Drinking Water


Nevins, H., Hyrenbach, D., Keiper, C., Stock, J., Hester, M., and Harvey, J. (2005). Paper presented at Plastic Debris Rivers to the Sea Conference 2005 Seabirds as indicators of plastic pollution in the North Pacific, www.oikonos.org/papers/Nevins_etal_2005.pdf Off-site Link

» Moore, Charles. (Nov., 2003). “Trashed: Across the Pacific Ocean, plastics, plastics, everywhere.” Natural History, 112.9:46-51.
Off-site Link

For more topic references visit the Resources section

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