URI scientist examining effects of plastic by-product on humans

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KINGSTON, R.I. – February 1, 2011 – A University of Rhode Island researcher is looking for clues about how a chemical in plastic affects humans.

Angela Slitt, assistant professor of biomedical and pharmaceutical sciences in URI’s College of Pharmacy, has a five-year $2.1 million grant from the National Institute of Environmental Health Sciences to study Bisphenol A, more commonly known as BPA. She is examining mice exposed to BPA to learn more about the compound’s potential effects on humans.

It is a by-product of plastics manufacturing, generally found in polycarbonate-based products such as food and drink storage containers, baby bottles, metal can linings and juice boxes. The food in the various types of containers then absorbs the chemical, which is later consumed and metabolized.

The major concern, and a research topic needing further study, is how the chemical actually affects the human body. In previous studies and in Slitt’s, the chemical has been shown to be a bodily disruptor, negatively affecting hormone levels, increasing risk for cancers, reproductive organ dysfunction and metabolic disorders.

In 2008, the U.S. Food and Drug Administration conducted a review of toxicology research and information on BPA and considered food-related materials containing the chemical to be safe. Providing $30 million in funding to investigate BPA, the National Institute of Environmental Health Sciences and the FDA are further studying the safety issues and the metabolic processes of the chemical.

“The biggest concern is in utero and lactation exposure to low concentrations of the chemical and how that dictates later effects,” said Slitt. “In rodents, exposure in the womb or during lactation has been associated with incidents of increased obesity, an already serious problem for Americans.”

The early exposure of mice to BPA has also been used to study gene expression changes.

“We exposed the mice in utero and lactation to BPA, then stopped exposure later on,” said Slitt. “We found that their livers do not look the same as mice whose mothers were never exposed to BPA. We have collaborated with Tufts Medical School and the University of Missouri to show how BPA exposure affects the liver through fat accumulation and gene expression analysis.”

Along with studying the impact of BPA, Slitt and her research team are also studying the different bodily conditions such as obesity, antioxidant intake, fasting and caloric restriction that affect bodily processes that aid in BPA elimination. For example, the research team used lean and overweight mice to see if BPA was processed differently.

“Using this data, we will determine whether good nutrition and proper caloric intake decrease body BPA levels. We also were looking to see if the chemical can be stored in fat deposits and if it is, if the body can purge BPA toxins during weight loss. This is an especially important question to ask regarding overweight and obese women who are pregnant, because weight loss during early weeks of pregnancy could theoretically increase fetal BPA exposure,” said Slitt.

Using money from the Recovery and Reinvestment Act (federal stimulus funding), Slitt was able to hire additional researchers, two URI undergraduates, three Rhode Island high school students, and a local high school teacher.

Summer research participants were: Olivia Diprete, Narragansett High School, Connie Wang, South Kingstown High School, Adam Reis, Narragansett High School science teacher, Jamie Moscovitz of Cranston, URI biology major, and Nelson Knudsen of Narragansett, Moravian College biochemistry major.

“It’s a really valuable opportunity for high school students to stay interested in the sciences and to be in a lab setting, doing the basics even if they don’t understand everything. It piques their interest and makes them realize that the sciences are a tangible subject and not something you just read about in textbooks,” Slitt said.

With the remaining recovery act money, Slitt will send the high school students who assisted her to the annual Society of Toxicology meeting this March in Washington, D.C.

Along with the research that has been conducted, Slitt stresses the need for more investigation.

“Much more work must be done to determine whether BPA affects humans in the same way it affects rodents,” she said. “We also need to be aware of where BPA comes from and how to avoid it when possible.”

Pictured above

Dr. Angela Slitt and her research team (from left to right): Ajay Donepudi, Laura Armstrong, Dr. Jialin Xu, Dr. Angela Slitt, Vijay More, Wei Wei, Dr. Margaret Teasdale, Supriya Kulkarni

Dr. Angela Slitt and URI postdoctoral fellow, Jialin Xu examine a western blot x-ray film, which measures protein changes of mice used in observation.

URI Department of Communications & Marketing photos by Michael Salerno Photography.

This release was written by Alicia Blain, an intern in URI’s Department of Communications and Marketing and a public relations major.