On the seventh anniversary of the Deepwater Horizon disaster, the health impacts that the spewing oil had on the people who came into contact with it are still raising questions about how the cleanup was handled.The latest studies by the National Institutes of Health found that the thousands of workers who came into contact with the oil that coated the coastlines of four states in 2010 were more susceptible to health woes during the cleanup, according to Dale Sandler, chief of the NIH's epidemiology branch."People who had the greatest exposure were more likely than other workers to report itchy eyes, burning throats, coughing, wheezing and skin irritations," she said.Often those symptoms were initially blamed on heat exhaustion, she said. But the NIH found that the workers in contact with the oil experienced those symptoms two to three times more than other workers who were not in contact with the oil."We were seeing symptoms that were not part of the definition of heat stress," she said.At this point, the NIH experts cannot say for sure that those symptoms were the result of chemical exposure, but that's the theory they're exploring.The Deepwater Horizon disaster began with a deadly explosion on April 20, 2010, and grew worse and worse from there. The oil rig 150 miles off the Louisiana coast exploded, killing 11 people and injuring 17. The rig sank, and two days later oil began gushing from 5,000 feet below the Gulf of Mexico's surface.Oil washed up on the coasts of Louisiana, Mississippi, Alabama and reached Florida in June. Thousands of shiny, reddish-brown globs, some as big as Frisbees, tainted the sugar-white beaches across eight counties, while tar mats the size of throw rugs floated just offshore.BP wasn't able to shut off the flow until July, which meant an estimated 4.9 million barrels of oil had spewed out and spread through the gulf. Some of it settled on the ocean floor, and there it still lies according to studies by University of South Florida scientists.To clean up the oil that tainted the beaches and mangrove shores, BP hired 55,000 people, many of whom had been previously unemployed and had no prior experience with oil spills.They would work in the sun for 10 minutes, then sit in the shade for 50, or put in 14 hours at night when no one saw them. They wore hard hats and steel-toed boots as they trudged along the beach scooping up tar balls.In the past 50 years, in 40 known oil spills around the world, only eight have been studied for human health impacts. Those studies found that cleanup workers exposed to crude oil often suffer acute short-term effects — stinging eyes, rashes, nausea, dizziness, headaches, coughs and other respiratory symptoms. But there have been no studies of the long-term health effects.So in February 2011, the NIH announced it would spend a decade studying the health impact on the cleanup workers — the largest such study in the agency's history.About 33,000 of the people who had played some role in the cleanup agreed to participate. Two years ago, Sandler reported that the earliest results from the study had found that the incidence of continued wheezing and coughing among the former cleanup workers was 20 to 30 percent higher than among the general public. The study will continue through 2021.BP officials have repeatedly said that the protection of workers and public health were among their top priorities during the cleanup.Under terms of a government settlement with BP over damage done by the spill, Florida is due to get $3.25 billion paid out over 18 years to "benefit areas of the state most devastated by the spill."Contact Craig Pittman at [email protected] Follow @craigtimes.