Formaldehyde - a colorless, flammable and strong-smelling chemical used in consumer products and in medical labs - is now being listed as a 'known human carcinogen' in a new federal government report.

Formaldehyde falls under that designation in the 12th Report on Carcinogens, the National Institutes of Health said Friday.

In addition, styrene, often used in food containers, may cause cancer, the NIH said.

The document by the U.S. Department of Health and Human Services identifies chemicals and biological agents that may put people at increased risk for cancer.

HHS notes that simply being listed in the report does not mean the substance will cause cancer. Other factors include the amount and duration of exposure and an individual's susceptibility to a substance.                

Below is a detailed description of Formaldehyde from HHS:

Formaldehyde is a colorless, flammable, strong-smelling chemical that is widely used to make resins for household items, such as composite wood products, paper product coatings, plastics, synthetic fibers, and textile finishes. Formaldehyde is also commonly used as a preservative in medical laboratories, mortuaries, and some consumer products, including some hair straightening products.

Other Chemicals

Aristolochic were also added to the list as a known human carcinogen.

Five other substances are reasonably anticipated to be human carcinogens.

They include: capfafol, cobalt-tungsten carbide (in powder or hard metal form), certain inhalable glass wool fibers, o-nitrotoluene, riddelliine.

With the new additions, the 12th Report on Carcinogens now includes 240 listings.