Written by the 1 Mississippi intern Natalie:*
Pollution is not only unpleasant to look at–it can have deeper effects on the human body and other living organisms. Charles Tyler and his team at the U.K.’s University of Exeter used genetically modified zebrafish (Danio rerio) to visualize these effects from common chemicals that pollute freshwater sources. Previous research has shown us that the endocrine system, responsible for the secretion of hormones, can be disrupted by substances found in plastics, paints, female contraceptives, and industrial detergents. The changes caused by these endocrine disruptors have shown to cause fish to change gender and are correlated with breast and testicular cancers in humans.
To look further into the effects of endocrine disruptors, Tyler and his colleagues genetically modified zebrafish to glow where endocrine-disrupting chemicals were present when viewing the fish under a fluorescence microscope. This would show where the chemicals are harming the zebrafish. The fish were exposed to ethinyloestradiol (found in contraceptive pills), nonylphenol (found in paints and industrial detergents) and BPA (found in plastics) All of these chemicals are common freshwater pollutants and notorious for their effects on the hormone estrogen. After exposing the zebrafish to varying concentrations of the endocrine disruptors, researchers were able to identify which organs and tissues of the body were affected by the chemicals. Previous research had indicated that these endocrine disrupting chemicals particularly affect the ovaries, testes, and liver, but Tyler and his team also found effects on tissues in the brain, eyes, and skeletal muscles. The exact impact of the pollutants on these areas is not known, but it does provide a base for future research.
So while protecting the environment is important for creating a clean and more beautiful place to live, it also protects humans and animals from harmful chemicals that can cause cancers and problems such as sterility. So what can you do? Limit your use of materials containing harmful chemicals whenever you can and replace them with materials that are friendlier to the environment. And when you do need to use these materials, make sure you properly dispose of them.
*Field Notes are a new series from the 1 Mississippi campaign, created and developed by our regional campaign interns as a means to encourage River Citizen engagement and to help our interns grow as environmental leaders.