March 2001 University Reporter

by Jeffrey Mitchell

2 men on boat "I like the oceans," says marine chemist Robert Chen of UMass Boston's Environmental, Coastal, and Ocean Sciences (ECOS) Department. It's clear that he also likes the young science of oceanography, through which he pursues a lively concern for "the health of ecosystems and the health of people."

Coastal ecosystems are especially vulnerable to human influence, and contaminants in them are especially likely to threaten human health in turn. But until recently, scientific knowledge has been limited by the difficulty of testing and measurement in these constantly changing environments. That's no longer the case, thanks to new technology. A prime example is the ECOShuttle, which rests in a lab down the hall from Chen's office—when it isn't "flying" under water at depths of three to fifty meters, towed by a research vessel and controlled from above by means of anadjustable fin.

The ECOShuttle has already explored coastal areas well beyond Boston Harbor, among them Chesapeake Bay, San Francisco Bay, and the Mississippi River plume in the Gulf of Mexico. Instruments in it can measure such variables as temperature, salinity, depth, fluorescent dissolved organic matter, hydrocarbon concentrations, and dissolved oxygen. Through a tube in the tow cable, water can be pumped up to a shipboard lab for additional testing on the spot or for later analysis. The ECOShuttle is versatile enough to measure organic carbon, for example, in three dimensions six times a second. It's not versatile enough for shallow estuaries, but a new mini-shuttle will soon answer this need.

Such technology is supporting a number of major studies. One deals with endocrine disruptors, which alter growth and development or reproductive success. For example, says Chen, "if juvenile male rainbow trout are caged in the River Thames, they become feminized because of chemicals in the water." Endocrine disruptors, says Chen, "may be the next wave of contaminants the EPA has to look at. There may be 40,000 contaminants that disrupt endocrine systems at some level."

Together with Ana Soto of Tufts Medical School, Chen will be using an MIT Sea Grant to analyze endocrine disruptors in Massachusetts Bay. Soto has developed a bioassay that uses human breast cancer cells to detect substances that may affect humans and other organisms. The bioassay is extraordinarily sensitive to estrogenic activity but does not identify individual substances; Chen and his associates will analyze sewage and seawater samples that have shown high rates of activity, and identify its sources.

Another substance often found in coastal waters is caffeine. "If you find caffeine," says Chen, "you might find other things—pesticides, pharmaceuticals, human pathogens, other sewage-derived contaminants." Caffeine is also much easier to measure than these dangerous substances, and Chen is therefore exploring its relationships with them.

Yet another project is a study of colored organic carbon in estuaries, funded by the Office of Naval Research. "The Navy's interested," says Chen, "because they want to know all about the optical properties of water," which affect surveillance of underwater activity from space. But the study has other applications too. "We're burning fossil fuels and increasing greenhouse warming," says Chen. Much of the burnt matter has been traced, but scientists puzzle over a "missing sink" of atmospheric carbon dioxide. "No one knows where it's going. And to know where it's going is critical to predicting what's going to happen as CO2 increases." Chen will pursue the possibility that some of the "missing sink" is dissolved organic carbon in the coastal ocean.

And soon, Chen hopes, the National Science Foundation will fund a new proposal for supporting thirty graduate students in work on recovering coastal ecosystems, of which Boston Harbor itself is a remarkable example. These "healing" ecosystems present unique problems for science, since no one has seen their like before. About half of the students would be based at UMass Boston, while others would study at other UMass campuses or at Florida A&M University, a partner institution. Their presence would generate an abundance of new research activity, and they themselves would become the "next generation of scientists" to oversee the recovering ecosystems.

Chen speaks with pleasure of the ECOS department, which he joined in 1993. He admires his colleagues' work in environmental science and policy—they're "very good at it"—and he enjoys the environment in his department. "What has kept me here," he says, "is that we're a very close-knit group. We actually collaborate! We have lunch together, we talk together, we share ideas—and we're growing now. These are exciting times."

Image: Robert Chen (right) and graduate student Ray Siegener on the research boat they use to study seawater caffeine levels. (Photo republished with permission of Globe Newspaper Company, Inc)

"Exciting Times" in the Study of Coastal Ecosystems

by Jeffrey Mitchell

Image: Robert Chen (right) and graduate student Ray Siegener on the research boat they use to study seawater caffeine levels. (Photo republished with permission of Globe Newspaper Company, Inc)