What affect did last year's BP oil spill have on changing government and energy company policies? And how can we assess the damage of the spill when so many conflicting scientific reports are continuing to be published?

It would take 86 days to stop the oil from flowing after the explosion of British Petroleum's Deepwater Horizon rig that killed eleven men and spewed millions of barrels of crude oil into the Gulf of Mexico. Exactly one year later, the US Gulf Coast is still trying to recover from the large amounts of destruction caused by the country's worst offshore oil spill.

On Tuesday's Riz Khan Show, we talk to Mike Robichaux, a Louisiana physician who has been treating patients suffering from mystery illnesses believed to be caused by the effects of the accident; Cherri Foytlin, a woman who walked from New Orleans to Washington to highlight the suffering of victims of the spill; and Carl Safina, a prominent ecologist and author of "A Sea in Flames: The Deepwater Horizon Oil Blowout."

You can watch the show at 1930 GMT on Al Jazeera English. Repeats will air next day at 0430 GMT, 0830 GMT and 1430 GMT.