CHALMETTE, La. (AP) -- When a BP oil well began gushing crude into the Gulf of Mexico four years ago, fisherman George Barisich used his boat to help clean up the millions of gallons that spewed in what would become the worst offshore spill in U.S. history.
Like so many Gulf Coast residents who pitched in after the April 20, 2010, explosion of the Deepwater Horizon rig, Barisich was motivated by a desire to help and a need to make money -- the oil had destroyed his livelihood.
Today he regrets that decision, and worries his life has been permanently altered. Barisich, 58, says respiratory problems he developed during the cleanup turned into pneumonia and that his health has never been the same.
"After that, I found out that I couldn't run. I couldn't exert past a walk," he said. His doctor declined comment.
Barisich is among thousands considering claims under a medical settlement BP reached with cleanup workers and coastal residents. The settlement, which could benefit an estimated 200,000 people, received final approval in February from a federal court. It establishes set amounts of money -- up to $60,700 in some cases -- to cover costs of various ailments for those who can document that they worked the spill and developed related illnesses, such as respiratory problems and skin conditions.
It also provides for regular physical examinations every three years for up to 21 years, and it reserves a worker's right to sue BP over conditions that develop down the road, if the worker believes he or she can prove a connection to the spill.
Some 33,000 people, including Barisich, are participating in a massive federal study that aims to determine any short or possible long-term health effects related to the spill.
"We know from ... research that's been done on other oil spills, that people one to two years after ... had respiratory symptoms and changes in their lung function, and then after a couple of years people start to return to normal," said Dr. Dale Sandler, who heads the study overseen by the National Institutes of Environmental Health Sciences, an arm of the National Institutes of Health.
"What nobody's ever done is ask the question: Well, after five years or 10 years are people more likely to develop heart disease, or are they more likely to get cancer?" Sandler said in an interview with The Associated Press. "And I'm sure that's what people who experienced this oil spill are worried about."
At a Friday news conference, Sandler discussed some of the study's early findings. She said depression and anxiety are common in and around disaster sites, but there are indications that cleanup workers were more likely to suffer mild to moderate depression than others living in Gulf Coast counties and parishes where economies and livelihoods were affected by the spill.
"After we took into account where people lived and other factors, it does appear that the prevalence of depression was about 30 percent higher among those who had cleanup jobs than among those who did not," Sandler said. "The preliminary trends were similar for anxiety."
She cautioned that the findings were preliminary and added that it is too early to tell whether exposure to oil or chemical dispersants might account for the difference.
The study is funded by NIH, which received a $10 million award from London-based BP, part of $500 million the oil giant has committed to spend over 10 years for environmental and health research.
Researchers compiled a list of 100,000 candidates, drawn from sources including rosters of mandatory safety classes that cleanup crews attended and from records of people who were issued badges permitting access to oiled areas.
They reached nearly 33,000 for interviews, mostly cleanup workers but also some who applied for cleanup work but were not hired. Of those interviewed, about 11,000 went through physical examinations that included blood and blood pressure tests and measurements of lung function. Water and air samples taken during the spill also will be used to attempt to pinpoint how much exposure workers may have had to toxic substances.
Sandler said Friday that about 4,000 of those who had physical exams will be invited to take part in a second round at medical facilities at one of two locations: The University of South Alabama in Mobile or LSU Health Sciences Center in New Orleans. Meanwhile, all of the original participants will be encouraged to keep taking part in surveys in the project, which Sandler hopes will continue for at least 10 years.
In the AP interview, Sandler emphasized that making any direct correlation between health concerns and the spill could prove challenging because many of the workers held other jobs that put them in contact with oil. Some worked with boat engines, did regular hazard mediation work or worked at chemical plants. Many also are smokers.
The researchers will try to account for smoking or other factors that could ruin health, and narrow in on problems tied to spill exposure. They plan to monitor the health of study participants for at least 10 years, maybe longer.
Fisherman Bert Ducote says he knows physical and emotional pain from having worked the cleanup. Ducote said dozens of boils have turned up on his neck, back and stomach since the spill -- and he theorizes, though shared no medical records that could prove, that his problems stem from the cleanup.
Ducote said he spent months handling the boom used to corral oil. Even with protective gear and rubber boots, he said his shirt often got wet with the combination of crude oil, sea water and chemical dispersant. Ducote, like Barisich, said he is filing a claim under the medical settlement.
"That has been a disaster in our lives," said Ducote, from the town of Meraux, in coastal St. Bernard Parish. "The little amount of money they're trying to give us, it's never going to replace our quality of life, our health."
In response, BP points to language in U.S. District Judge Carl Barbier's order approving the medical settlement. Barbier noted that both sides said the settlement was a fair and reasonable alternative to litigation, and that fewer than 100 of 200,000 potential class members objected.
BP also lists numerous steps it took after the disaster to protect workers' health, including protective clothing and safety classes.
Cleanup workers who faced possible contact with oil and dispersants were "provided safety training and appropriate personal protective equipment, and were monitored by federal agencies and BP to measure potential exposure levels and help ensure compliance with established safety procedures," BP said in an email to The Associated Press.
Not all used that equipment, however. Dr. Edward Trapido, a cancer specialist and the lead researcher on a study of cleanup crews and their families that is underway at the Louisiana State University Health Sciences Center, said many worked without the protective clothing because of sweltering heat.
Trapido said results of the long-term health studies could help improve response to future oil spills and other disasters.
"Oil is not going away, and whatever kind of energy it is -- whether it's nuclear, whether it's coal or oil -- all of these have had problems in recent years where people get exposed to it," Trapido said.