URI researcher to evaluate how to measure “emerging contaminants” in Narragansett Bay

Posted on
NARRAGANSETT, R.I. – September 22, 2008 – As more and more chemical compounds are finding their way into local waterways, scientists must seek ways to monitor those compounds that are believed to be potentially harmful to people and the environment.

A University of Rhode Island researcher has been awarded a $300,000 grant to do just that. Rainer Lohmann, a URI chemical oceanographer, will test the effectiveness of a simple system for measuring three of these “emerging contaminants” in Narragansett Bay.

In an award-winning paper published in 2007 in the Journal of Environmental Science and Technology, Lohmann demonstrated the use of a polyethylene sheet — sold at most hardware stores for $1 as a painter’s drop cloth – to detect contaminants like PCBs, dioxin, and oil components in water. Chemical compounds that are dissolved in water become absorbed into the polyethylene.

Lohmann now plans to test its effectiveness at detecting three contaminants that are not typically monitored by the U.S. Environmental Protection Agency but which are increasingly found in waterways and are considered hazardous: triclosan, a disinfectant found in a wide variety of cleaning products but which reacts with sunlight to form a toxic dioxin; alkylphenols, which are found in surface cleaners, detergents and other products and cause reproductive impairments in fish and other marine life; and flame retardants, which persist in the environment and accumulate in the tissues of wildlife.

“Very few measurements have been done for these classes of compounds in the past, yet they are relatively easy to detect and are found in most bodies of water,” Lohmann said.

The polyethylene sheets, which Lohmann calls passive samplers, will be attached to buoys at several locations around the northern portion of Narragansett Bay, as well as around Prudence Island and off the URI Bay Campus in Narragansett. Sites adjacent to sewage treatment plants and storm water overflows will be targeted because the chemicals likely enter the bay from these facilities.

The study began this summer with laboratory tests to learn how the compounds become absorbed into the polyethylene. Field tests in Narragansett Bay will begin next spring and continue for one year. The samplers will remain in the water for 1-2 weeks at a time.

Lohmann hopes to work closely with the Narragansett Bay Commission to identify the source of the compounds and the quantities that pass through its facilities.

The grant, from the National Oceanic and Atmospheric Administration through the Cooperative Institute for Coastal and Estuarine Environmental Technology at the University of New Hampshire, also includes an outreach component.

“I’ll be reaching out to interested community groups around the bay, including watershed groups, Save the Bay and others, who might want to use this same system for testing ponds, rivers and other places for these and other compounds,” Lohmann said. “We could then create a map of Narragansett Bay and its tributaries to show where various compounds are found.”