The chemicals that are used to make non-stick cookware, microwave popcorn bags and stain- and water-repellent fabric may also raise cholesterol levels in children, a new study suggests.

The research found that children with the highest blood levels of compounds called perfluoroalkyl acids had higher levels of total cholesterol and low-density lipoprotein -- the so-called "bad" cholesterol -- compared to children with low readings.

The findings do not prove that exposure to perfluoroalkyl acids caused the children's cholesterol levels to rise, but they do suggest the need for more study, say Stephanie Frisbee of West Virginia University and colleagues in the Archives of Pediatrics & Adolescent Medicine.

Perfluoroalkyl acids are used to make the substances that give non-stick heat resistance to cookware and that make fabrics and upholstery water- and stain-resistant.

The compounds are also used as a coating for commercial food packaging – to keep popcorn from sticking to microwaveable popcorn bags, for example.

Studies have shown that almost all humans have traces of the compounds in their blood, and are exposed to them from everything from dust to factory work.

As for how the chemicals could be affecting cholesterol levels, animal studies have shown that the primary organ that's affected by perfluoroalkyl acid exposure is the liver, which is the organ responsible for cholesterol production.

For this study, Frisbee and her team assessed cholesterol levels in 12,476 kids and teens up to the age of 18. The kids were part of a health project that began during a class-action lawsuit against Dupont involving the landfill dumping of chemicals that contaminated groundwater near the company's plant in Parkersburg, West Virginia.

Blood samples were taken from the children, all of whom were exposed to drinking water contaminated with perfluorooctanoic acid (PFOA).

The average PFOA concentration in their blood was found to be 69.2 ng/ml; average levels of a related compound, called perfluorooctanesulfonate (PFOS), was 22.7 ng/mL -- both much higher than the national median.

Among 12- to 19-year-olds, their PFOA concentrations were substantially higher than those found in kids nationally: 29.3 ng/mL for the study group, compared to 3.9 ng/mL for others.

The researchers found that the kids with higher PFOA levels had higher total cholesterol levels, as well as increased levels of LDL cholesterol.

Higher levels of PFOS, meanwhile, were linked with increased total cholesterol, LDL cholesterol and HDL, or "good," cholesterol. The study found an average difference of 8.5 mg/dL in total cholesterol levels between the one-fifth of participants with the highest and the fifth with the lowest PFOS levels.

There was no link between either compound and triglyceride levels.

"PFOA and PFOS specifically, and possibly perfluoroalkyl acids as a general class, appear to be associated with serum lipids, and the association seems to exist at levels of PFOA and PFOS exposure that are in the range characterized by nationally representative studies," the authors of the study said.

The authors conclude by calling for more research into exposure to the family of perfluoroalkyl acids.