NEW YORK (Reuters Health) – People who had higher levels of a common synthetic chemical in their blood were more likely to have heart disease or have had a stroke, in a new U.S. study.

The chemical, known as perfluorooctanoic acid or PFOA, is found in everything from food containers to ski jackets to carpets. But the lead researcher emphasized that the new findings don’t prove PFOA itself is dangerous or should be avoided.

  “I don’t think these results should be taken as alarming. These are preliminary at this stage,” said Dr. Anoop Shankar, from the West Virginia University School of Public Health in Morgantown.

That’s because it’s not clear what came first for people in the study – the higher chemical levels or the heart disease. And research suggests almost all Americans have some level of PFOA in their blood, Shankar added.

His team used data from 1,216 people in a national survey who had blood tests and answered questions about their history of a range of diseases in 1999 through 2003.

Most of them were white and in their fifties, on average.

Once they had accounted for participants’ age, race and other risk factors for heart disease, the researchers found those with the highest levels of PFOA were about twice as likely to report heart problems or strokes compared to those with low chemical levels.

Shankar said PFOA in the blood has also been linked to higher cholesterol and blood pressure and to insulin resistance – all of which can contribute to cardiovascular disease. But it’s still not clear from the findings that PFOA caused heart problems, or even that PFOA levels were higher than normal before people got sick.

For example, Shankar told Reuters Health, it’s possible that people with heart disease and heart failure may develop kidney problems as a result – meaning the kidneys would have more trouble clearing chemicals like PFOA from the blood.

Early studies in animals did not show serious health effects related to PFOA exposure, Shankar said – another reason that his research will have to be backed up before anyone should be concerned.

“Unlike a lot of other environment contaminants, these chemicals were considered to be inert,” Shankar said.

His study, published Monday in the Archives of Internal Medicine, was funded by grants from the American Heart Association and the National Institutes of Health.

Dr. Debabrata Mukherjee, chief of cardiovascular medicine at Texas Tech University in El Paso, said that even though researchers can’t prove a cause-and-effect link, people might want to reconsider buying products that contain PFOA if they have a choice.

“I think this raises a red flag,” said Mukherjee, who wrote a commentary on the new study.

He said people can check labels to make sure household products don’t contain PFOA or toxic fluorocarbons in general. Many companies are making “greener versions” of the same products now.

  “It would be prudent to avoid this. If there are safer alternatives, why would you risk having something add to your cardiovascular risk?” he told Reuters Health. “As a consumer, I would say, be careful about what you buy.”

Some chemical companies including DuPont have agreed with the Environmental Protection Agency to work toward eliminating PFOA from products by 2015.

The American Chemistry Council, a trade association for the chemical industry, put out a statement noting the weaknesses of the study, as acknowledged by Shankar, and added that the results aren’t in line with past studies.

Mukherjee pointed out that there are more important risk factors for people worried about their cardiovascular health to address.

“Let’s also remember to take care of ourselves – exercise regularly, don’t smoke (and) follow a judicious diet,” he said.