GuLF Study Environmental Health Sciences (NIEHS), part of the National Institutes of Health, and aims to recruit 55,000 of the 150,000 workers who volunteered or were employed to help clean up the spill. It is led by Dale Sandler, head of the NIEHS's epidemiology branch. The "Deepwater Horizon" oil spill was the world's largest accidental marine oil spill. It began on 20 April 2010 after an explosion on the "Deepwater Horizon", a drilling rig leased by BP to drill an exploratory well. Between then and 15 July, when the well was capped, over four million barrels of oil (around 170 million US
Gulf of Mexico BP reached an $18.7bn settlement with the US government, the states of Alabama, Florida, Louisiana, Mississippi and Texas, as well as 400 local authorities. To date BP's cost for the clean-up, environmental and economic damages and penalties has reached $54bn. According to the National Response Center, the oil industry has thousands of minor accidents in the Gulf of Mexico every year. On May 12, 2016, a release of oil from subsea infrastructure on Shell's "Brutus" oil rig released 2,100 barrels of oil. This leak created a visible 2 mile by 13 mile oil slick in the sea about 97 miles