NOAA's Mussel Watch collects samples from areas between high and low tides and from shallow subtidal waters such as this site along the shores of Cook Inlet, Alaska. Samples are brushed clean and shipped on ice to a laboratory for chemical analysis to test for contaminant levels.
A NOAA report released on April 1 finds that human-made toxic chemicals used as flame retardants in consumer products are found in all U.S. coastal waters and the Great Lakes.
The chemicals—Polybrominated Diphenyl Ethers, or PBDEs—have generated international concern in recent years due to their global distribution and associated adverse environmental and human health effects.
The report is based on data from NOAA's Mussel Watch Program, which has been monitoring coastal water contaminants in mussels and oysters for 24 years.
"Even though PBDEs were first looked at in the human environment, they are clearly now in the marine environment in mussels and oysters. But mussels and oysters are, in a sense, a canary in the coal mine for environmental contaminants," said Dr. Gunnar Lauenstein, program manager for NOAA's Mussel Watch.
While the chemicals were found in coastal areas throughout the U.S., the report found the highest PBDE concentrations in areas with dense human populations such as in Southern California and the waterways around New York City.
Monitoring sites for NOAA's Mussel Watch, the longest continuous contaminant monitoring program in U.S. coastal waters.
Laboratory studies indicate that PBDEs may impair liver, thyroid, and neurobehavioral development, and the most sensitive populations are likely to be pregnant women, developing fetuses, and infants.
"PBDEs can be as much as 30 percent by weight in cushions found in things like couches. So when we sit on a couch, there could be a possible invisible cloud of PBDEs that we're breathing," Lauenstein said.
"From what I've read in the literature, infants or young toddlers frequently have the highest PBDE concentrations in the household and that may be because they crawl on the floor, there's PBDEs in the carpet padding, and then the infants put their fingers in their mouths. And there's also literature that suggests that PBDEs, because they're fat loving, or lipophilic, they can be transferred from mother's breast milk to their infants," he added.
Dr. Gunnar Lauenstein, NOAA Mussel Watch program manager, brings up a rock covered with zebra mussels.
While production of PBDE flame retardants began in the 1970s and peaked in 1999, they are still found in many consumer products. Because the application of PBDEs has been so widespread—including many consumer plastics, textiles, electronics, and furniture—scientists speculate that they may present an ongoing and growing problem in coastal environments.
"PBDEs can move into the environment through a number of ways. PBDEs can move into the environment from municipal waste; PBDEs can move into the environment from consumer goods as they're discarded; PBDEs and PCBs* both can move up into the atmosphere, and this is one way that they are not only local from where their source is, but they can be broadcast throughout our world environment," Lauenstein said.
Lauenstein said the findings of the long-term monitoring study point to the need to rethink how we handle products laden with PBDEs. For instance, most municipalities today discard old couches in landfills. If these landfills leak, there is a threat that PBDE chemicals will be released back into the marine environment or groundwater. Alternatively, if a couch is incinerated, PBDEs may be released via stack gases and wind up in the atmosphere.
"We in a sense have a cycle here: we have human consumerism and PBDEs, or flame retardants, being released in to the environment, moving into the marine environment, and from the marine environment possibly moving back into the human environment," Lauenstein said.
"This study gives decision makers and managers a tool to see the extent of PBDE contamination in our coastal environment and hopefully help in the decision process."
The report, entitled "An Assessment of Polybrominated Diphenyl Ethers (PBDEs) in Sediments and Bivalves of the U.S. Coastal Zone" was produced by NOAA's National Centers for Coastal Ocean Science Mussel Watch Program with support from NOAA's Ocean and Human Health Initiative.
Mussel Watch is the longest-running estuarine and coastal pollutant monitoring effort in the United States that is national in scope.
*PCBs, or polychlorinated biphenyls, are a class of toxic chemicals once used in consumer products that share similar qualities to PBDEs.