April 20, 2011 marks the one-year anniversary of BP's catastrophic oil disaster in the Gulf of Mexico...It is, to date, the largest accidental marine oil spill in the history of the petroleum industry. BP has used at least 1.9 million gallons of toxic dispersants to sink the oil, in an effort the oil giant claimed was aimed at keeping the oil from reaching shore. Critics believe the chemical dispersants were used simply to hide the oil and minimise BP's responsibility for environmental fines…[T]oxicologists, and medical doctors have described the impact of the disaster upon the environment and human health as "catastrophic," and [said]…that this is only the beginning of that what they expect to be an environmental and human health crisis that will likely span decades...Dr Mike Robicheux is a doctor in Louisiana who has been treating scores of people he says are being made sick from BP’s toxic chemicals...Robicheux...said: "We are going to have thousands of people who are extremely sick, and if they aren’t treated, a large number of them are going to die."