Perfluorooctanesulfonic acid

Perfluorooctanesulfonic acid (PFOS), also known as Perfluorooctane Sulfonate, is a global pollutant. Due to high levels detected in aquatic environments, PFOS was added to annex B of the Stockholm Convention on Persistent Organic Pollutants in 2009. PFOS may form from industrial production as well as the degrading of precursors. Levels of PFOS that are being detected in the environment, specifically aquatic environments, are high enough to considerably affect wildlife in the area. Recently, high levels of PFOS in the U.S. have been associated with chronic kidney disease in humans as well as wildlife. PFOS is a particularly damaging pollutant in the ocean. Increased levels of PFOS have been found in dolphins, harbor seals, orca whales, and fish in areas that had once been considered free of pollutants.

The health risks for both humans and aquatic creatures exposed to PFOS can greatly affect the population of both in the future, as overexposure to PFOS can affect the reproductive organs or an already conceived fetus. Unfortunately, PFOS is not a well known pollutant even though it is considered highly toxic and can have long lasting effects in aquatic life. PFOS is a consistent issue with marine biologists, as higher levels of PFOS can affect the health of aquatic creatures without being detected by normal means, and without affecting humans in the surrounding population.

Properties
Perfluorooctanesulfonic acid is a global pollutant that is corrosive and toxic to marine life and environments. PFOS is not only harmful to marine life, but can also be harmful to human health and is a known irritant that can cause difficulty breathing, redness of the eyes, and itchy skin. PFOS is a common pollutant most often found in the ocean, but exists as a white or pale yellow crystalline powder in pure physical form.

Most of the chemical properties of perfluorooctanesulfonic acid are not definite, but are in an experimental or predicted state. PFOS does not have a definite boiling point, but the experimental boiling point is 145 °C per every 10 mmHg and 313.0728 °C per every 760 mmHg. The melting point of PFOS is not known, nor is the experimental melting point, but the predicted melting point that is currently being studied is 90 degrees Celsius. The density of PFOS is known and has been confirmed as 1.25 g/mL. The solubility of perfluorooctanesulfonic acid in water is also known and has been confirmed as 520 mg/L. The pH, flash point, and vapor density remain unknown and unpredicted at this time.

Synthesis


The synthesis of Perfluorooctanesulfonic Acid is rather short at this point, mostly because it has not been observed, experimented, or tested extensively. The only known fact about the synthesis of PFOS at this time is that the process involves the use of perfluorooctanesulfonyl fluoride, or PSOF, as a feedstock.

Natural Occurrences
PFOS occurs naturally in almost every studied aquatic environment, or at least at this point this is the accepted data. PFOS has thus far been detected in drinking water, rivers, and even lakes across the world.

Uses
Historically, PFOS was used in sodium or potassium salts, but since then science has discovered the threat of PFOS to human health. Currently, PFOS is used as a key ingredient in Scotchgard, a fabric protector, and several stain repellants. It has also been used to make aqueous film forming foam, a necessary component in fire-extinguishing foams and alcoholic concentrated foams. Other compounds of PFOS can be remotely found in textiles, paper, leather, wax, polish, paint, and cleaning products used for sanitizing metal surfaces and carpets. PFOS itself may not be a semiconductor, but is used in the semiconductor industry in photoacid generators and anti-reflective coatings. European semiconductor industries have recently stopped using PFOS because of health concerns. It is also used hydraulic fluids and commercial aviation. Out of all these uses, the most important uses for Perfluorooctancesulfoic acid are in metal plating and fire-extinguishing foams.

Threat To Humans And Marine Life
Perfluorooctanesulfonic acid is a global pollutant that is toxic to marine organisms and can cause permanent or long-term effects in marine environments. When injected into a fish egg, scientists found that PFOS caused brain asymmetry and decreased immunoglobulin levels. Scientists have noted that PFOS affects the immune system, raising the possibility that the immune system of those highly exposed to PFOS may become compromised and weakened. Marine biologists have measured levels of PFOS in various marine species' eggs, liver, kidney, and blood plasma. Some of the highest recorded levels were in the egg of a guillemot in the Baltic Sea, the muscle of a harbor seal in Denmark, the plasma of a bottlenose dolphin in the Atlantic Ocean, the liver of a common dolphin in the Mediterranean Sea, and the liver of a mink in the Pacific Ocean. The levels found in all of these marine creatures vary in amount, but are all considered a sufficient amount to alter their state of health. Marine biologists have determined that PFOS causes cancer, delays in physical development, stunts in growth, endocrine (or hormone) disruption, and the most dramatic result of marine animal testing is neonatal mortality, the rate of infant death during the first twenty eight days after live birth. It has been found that PFOS reduced the birth size of marine mammals.

In addition to being a harmful marine pollutant, PFOS is also a known irritant. Exposure to perfluorooctanesulfonic acid may cause burning and redness of the eyes, burning and itchy skin, permanent damage to the digestive tract, severe burns to the gastrointestinal tract, and if inhaled may cause chemical burns to the respiratory tract. Upon exposure, PFOS may cause decomposition of the metabolism, nausea, vomiting, difficulty breathing, deterioration of bone and tooth structure, or kidney and liver damage. PFOS has also been found to cause reduced fetal growth in the womb.

Video
Usage of PFOS in water, soil and fish HRNL9LjzkqE