On 18 May, NOAA shut down fisheries in a 118,000-square-kilometer area in the gulf. The move has threatened the lucrative shellfish industry. But the government says it is crucial to protect people from dangers of eating shellfish contaminated with polycyclic aromatic hydrocarbons, elements of oil that are carcinogenic.
Scientists are scouring the area for tainted catch—so far, with the oil still offshore, none has been found—a tricky task in itself. Current analytical methods take days. So scientists at AOAC International, a nonprofit analytical chemistry group in Gaithersburg, Maryland, are working with testing companies to try to develop faster methods for preparing and analyzing samples with mass spectroscopy.
A far more difficult task will be determining when it is safe to reopen the fisheries. After previous spills, NOAA has reopened fisheries when normal background levels of oil were detected in fish or shellfish samples. But given the size of the fishery affected and its critical importance to local livelihoods, such a strict standard may be unrealistic. Former Food and Drug Administration regulator David Acheson says the agency may have to develop new standards to certify fish that contains tiny amounts of oil above trace levels. But that could take "a very long time," he says. "We don't really know what's safe."