Gulf oil spill health legacy yet to be revealed

About 150,000 workers involved in the clean-up have been exposed to unprecedented amounts of chemicals used to disperse the spill, the Lancet reports.

In addition, the effects of polycyclic aromatic hydrocarbons (PAH), such as benzene and toluene, which are products of crude oil, are known to include neurological problems and leukaemias. Exposure to PAHs subject to weathering is simply unknown, they said.

Thousands more people may be exposed to chemical residues in seafood which can remain in the food chain for a decade.