US study: Puerto Rico estuary highly contaminated
SAN JUAN, Puerto Rico (AP) — A federal study has found that a large estuary in southwest Puerto Rico has one of the highest concentrations of pollutants ever measured in the history of a U.S. monitoring program launched nearly three decades ago, scientists said Thursday.
Researchers found that Guanica Bay has unusually high levels of chlordane, once used as a pesticide, and polychlorinated biphenyls, or PCBs, a banned substance once used in part as coolant fluid for transformers.
The bay also has high levels of the metals chromium and nickel, according to the National Oceanic and Atmospheric Administration, which has run a nationwide contaminant monitoring program since 1986.
The three-year study was completed in 2012, and NOAA scientists believe the pollutants remain in the bay's sediment and are affecting nearby ecosystems.
"Sediment concentrations usually don't change that quickly over time," NOAA ecologist and lead investigator David Whitall said in a phone interview. "It was a little bit surprising to me that the PCBs are as high as they are."
Scientists say the contaminants pose a serious toxic threat to coral, fish and other organisms in the area. Whitall said humans also could be at risk if they eat fish caught in that region, noting the bay attracts fishermen.
Guanica Bay is located just east of La Parguera, a stretch of coastline popular with tourists. The bay is nestled in an industrial zone, but researchers do not yet know exactly what led to such high levels of contaminants.
NOAA officials have shared the information with Puerto Rico's government and with the U.S. Environmental Protection Agency, but it is unclear whether any type of cleanup is planned.
An EPA spokesman said officials did not immediately have comment, and a spokeswoman for Puerto Rico's Department of Natural Resources did not return a message for comment.
Guanica Bay also is the target of a U.S. watershed management plan aimed in part at protecting nearby coral reefs from runoff.
