Boxing great Muhammad Ali is receiving treatments from a doctor who believes the former champion's slurred speech and tremors stem from exposure to a household pesticide.

Ali, 46, arrived at Hilton Head Hospital earlier this week for the first in a series of blood-cleansing treatments supervised by Dr. Rajko Medenica, an immunologist who specializes in treating cancer and blood disorders.Ali appeared in fine spirits Wednesday after the initial eight-hour treatment.