Recent stories in the Mobile Register revealed that oil and gas operations dump more than 1 billion pounds of mercury-contaminated drilling fluids into the Gulf each year. The drilling fluids cool and lubricate drill bits as crews bore new wells.
Studies by the U.S. Minerals Management Service, which regulates the nation's offshore oil fields, indicate that mercury levels in the sand around some Gulf rigs are three times higher than levels found at EPA Superfund sites that are closed to all fishing. Mercury levels in some creatures living around those rigs are at least 25 times higher than levels found elsewhere in the Gulf.
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Mercury contamination around the 5,500 Gulf oil rigs may be particularly dangerous because Gulf fish and fishermen both swarm to the rigs, which appear to be the most mercury-contaminated spots in the Gulf. - source 1 - source 2
Of course MMS said the data was "not correctly interpreted":
Are drilling muds a source of mercury in the seafood we eat? This question was raised in January of 2002 when a series of newspaper articles appeared in the Mobile Register suggesting that oil and gas activities in the Gulf of Mexico were adding mercury to the environment. The added mercury was proposed as a source of mercury in fish consumed by local residents in Mobile, Alabama. Results from a Minerals Management Service (MMS) study, Gulf of Mexico Offshore Operations Experiment (GOOMEX)1, were used to demonstrate that this is true. However, the results of the study were not correctly interpreted. This report will present those results in the context of the global issue of mercury in the environment - source 3
You can believe that all the "right" people know of these practices. But the money means more to them - despite their oaths of office.