Health consequences of the Deepwater Horizon oil spill effects, while even very low doses can cause mutagenic effects, with cancer of particular concern. The carcinogens of concern in crude oil are benzene and polycyclic aromatic hydrocarbons (PAHs), which are present in oil and in the air as a result of offshore controlled burning of crude oil. During the 2010 BP/Deepwater Horizon Gulf oil spill, an estimated one of every 20 barrels of spilled oil was deliberately burned off. Routes of exposure include contact and inhalation. The EPA obtained hundreds of air samples during the spill and a review showed that none of the samples showed concentrations of benzene
Volume and extent of the Deepwater Horizon oil spill approached the Delta National Wildlife Refuge and Breton National Wildlife Refuge. On 19 May 2010, both NOAA and other scientists monitoring the spill with the European Space Agency Envisat radar satellite stated that oil had reached the Loop Current, which flows clockwise around the Gulf of Mexico towards Florida and then joins the Gulf Stream along the U.S. east coast. On 29 June 2010, NOAA determined that the oil slick was no longer a threat to the loop current and stopped tracking offshore oil predictions that include the loop currents region. The omission is noted prominently on the ongoing nearshore