The government says the industrial chemical formaldehyde causes cancer and that styrene, which is used worldwide in the manufacture of fiberglass and food containers, may cause cancer.
The National Institutes of Health says people with higher measures of exposure to formaldehyde are at increased risk for certain types of rare cancers, including in the upper part of the throat behind the nose.
The strong-smelling chemical is widely used to make resins for household items, including paper product coatings, plastics and textile finishes. It also is commonly used as a preservative in medical laboratories, mortuaries and consumer products including some hair straightening products.
The government says styrene is a component of tobacco smoke, and NIH says the greatest exposure to the chemical is through cigarette smoking.