By: Lea Winerman

Reports of fisherman who had been hired to clean up oil in the Gulf of Mexico falling ill have raised concerns about the health effects of the stew of oil and chemicals in the area.

On Wednesday, seven workers were hospitalized after complaining of headaches, nausea, vomiting and shortness of breath, and the Coast Guard recalled all 125 boats working in the area -- around Breton Sound -- as a precaution. Five workers were released but two remained in the hospital as of Thursday.

The incident has renewed questions about the effects of the oil -- and the chemical dispersants being used to clean it up -- on human health.

Coast Guard Capt. Meredith Austin told the Associated Press that no chemical dispersant had been used within 50 miles of where the workers became sick. She said that fatigue, working in hot weather, dehydration and the smell of petroleum could bring on the symptoms.

"We're not saying this to discount what happened to our people," she told AP. "But I just wanted to point out that there are other factors," she said Thursday.

BP also said Friday that all of the workers who fell ill Wednesday were properly trained and had protective gear on.

But other fisherman hired by BP have told reporters that they weren't issued protective gear before being sent out.

Fisherman George Jackson, who took a cleanup job after the spill closed the waters he fished in, told the Los Angeles Times that he wore leather boots and regular clothes on his boat.

"They [BP officials] told us if we ran into oil, it wasn't supposed to bother us," Jackson told the paper. "As far as gloves, no, we haven't been wearing any gloves."

Chemicals of concern include volatile organic compounds such as benzene and toluene, which are carcinogenic at high levels of exposure, and can cause headaches, nausea and other symptoms, along with a rotten-egg smell.

Officials say that monitoring in the area has not found alarmingly high levels of the toxic chemicals, according to the Washington Post.

"We're on the boats, we're on the beaches, we're in the marshes -- we're everywhere we need to be," Jordan Barab, deputy assistant secretary of labor for occupational safety and health, told the paper. "So far we have not found anything that causes great concern. If we do, we will respond immediately."

But Hugh Kaufman, a senior EPA official, questioned that assumption, according to the Washington Post. Kaufman compared the situation to that after September 11, when workers at the World Trade Center site became sick.

"It's like deja vu all over again," he told the paper. "We saw this on the Exxon Valdez. We saw this with Love Canal. We saw it with 9/11. How many times do we have to see this? There's no way you can be working in that toxic soup with getting exposures."

Meanwhile, one local congressman is asking federal officials for more help. Rep. Charlie Melancon, D-La., has asked Health and Human Services Secretary Kathleen Sebelius for help setting up medical clinics in the affected areas.