By CRAIG PITTMAN

Three years ago, during the Deepwater Horizon disaster, BP hired thousands of people across the Gulf Coast to don protective suits and go out in boats to collect the oil or to scrape up the tar balls washing ashore.

Now the government is watching 33,000 of those people to see if coming in contact with the oil made them sick.

The vast study, overseen by the National Institutes of Health, began signing up participants in 2011 and should last for a decade. So far, “it confirms much of what you would expect,” said Dr. Dale Sandler, who’s in charge.

The cleanup crew workers were exposed to the oil more than most Gulf Coast residents, she said. Many of them were people who had previously been unemployed. That means most of them had a history of poor health care.

In the years after the oil spill, many of them have once again been unemployed, which limits their access to care.

Add those things together and the results are predictable, she said.

“People just generally feel lousy,” she said. “In part, it’s because more of those people are out of work.”

Sandler’s findings so far are in sharp contrast to the results of a study released Friday by the Government Accountability Project that focused on complaints about health problems among workers exposed to the dispersant that BP sprayed on the spreading oil three years ago.

Workers complained of a wide range of ailments including blood in their urine, heart palpitations, memory loss, rapid weight loss, seizures, skin irritation and temporary paralysis, the report said. Many said they either received no safety training or were chastised for raising safety questions.

“Most of our members right now who are sick are in litigation,” Louisiana Shrimp Association vice president A.C. Cooper told investigators from the Government Accountability Project, which says it’s a public interest group focused on helping whistle-blowers get the word out about what’s going on inside their companies or agencies.

BP strongly denies putting anyone at risk. During the spill, BP officials assembled teams of toxicologists and industrial hygienists to assess potential risks to human health from the oil and the dispersants, a company spokesman said. They also looked for potential risks associated with the onshore cleanup, such as snake or rat bites, as well as from working in the summer heat of the gulf.

The company also collected more than 30,000 of what it called “response worker personal monitoring samples” to check on the cleanup crews’ exposure to toxic air pollution from the oil and dispersants. Nearly all of them registered levels considered safe, the company said.

But the National Institutes of Health study hopes to go beyond those results by talking to the workers themselves and reviewing their medical records for up to a decade — something that’s never been tried before.

“This is a hard, slow process,” Sandler said.

So far, she said, they have completed about 11,000 in-person interviews — some in English, some in Spanish, some in Vietnamese. The project is compiling information on what the workers did and where and when.

Although it’s too soon to say whether anyone has developed physical problems as a result of working on the spill cleanup three years ago, Sandler said, “there is a fair amount of psychological stress. There’s more depression and anxiety.”