Perfluoroctanesulfonic acid (CASRN: 1763-23-1)
Bethesda, MD: U.S. National Library of Medicine, Toxicology Data Network (TOXNET). [Database]
HERO ID: 3982555
IDENTIFICATION: Perfluorooctane sulfonic acid, also called PFOS, is a liquid. It is sparingly soluble . . .
IDENTIFICATION: Perfluorooctane sulfonic acid, also called PFOS, is a liquid. It is sparingly soluble in water.
USE: PFOS was an important commercial chemical that was used as a fabric protector (3M Scotchguard). PFOS was also used in fire-fighting foams. Its manufacture was stopped in 2002.
EXPOSURE: PFOS is widely distributed around the globe. It is found in soil, air and water. Workers who used or produced PFOS may have breathed in mists or have had direct skin contact. The general population may be exposed by dermal contact with fabrics treated with PFOS. Because PFOS is now found everywhere in the environment, people are exposed through food, in particular fish, and house dust. For people living near industries that made PFOS, exposure was from water, soil and air. PFOS has been found in very small amounts in the blood of people and animals worldwide. PFOS is extremely persistent. If PFOS is released to the environment it will not be broken down in air. It can travel long distances in the air on particles that eventually fall to the ground. It is not expected to be broken down by sunlight. PFOS may get into the air during windy days. It will not move into air from moist soil and water surfaces. It is not expected to move through soil. It may be carried through soil by groundwater and flooding. It will not be broken down by microorganisms, and is expected to build up in fish.
RISK: In general, data regarding the potential toxicity of PFOS are inconsistent. Additionally, it is currently under debate whether or not effects observed in animals are relevant to humans based on species differences in how the body reacts to exposure, particularly cancer effects. Therefore, health risks associated with exposure to PFOS are unclear. Increased cholesterol levels, increased risk of high blood pressure, thyroid disease, and liver damage have been associated with increased blood levels of PFOS in exposed humans in some studies. In laboratory animals, skin and eye irritation, weight loss, altered cholesterol levels, liver damage, and immune system impairment are the primary effects associated with exposure to PFOS. Data regarding the potential for PFOS to cause infertility, abortion, or birth defects in humans are not available. Birth defects, delayed development, and early deaths have been observed in laboratory animals exposed to PFOS during pregnancy. There is limited evidence that high occupational exposure to PFOS may increase the risk of bladder cancer; however, data for this endpoint are inconsistent. No other forms of cancer have been associated with PFOS exposure in humans. Liver tumors developed in laboratory animals exposed to PFOS over their lifetime. The potential for PFOS to cause cancer in humans has not been assessed by the U.S. EPA IRIS program, the International Agency for Research on Cancer, or the U.S. National Toxicology Program 13th Report on Carcinogens. (SRC)