PFAS is the toxic issue of our era, it has recently been reported that it is even coming down in rain. How did we get in this dire situation? If you want to unravel the complexities of PFAS, an historical understanding of the fluorine industry is required.
PFAS are a class of highly fluorinated anthropogenic chemicals. 12,000 different PFAS structures have been identified. PFAS molecules have a chain of linked carbon and fluorine atoms forming the strongest bond in organic chemistry. These form the basis of organofluorine compounds.
A fluorinated chemical therefore is a chemical that contains one or more fluorine atoms. To understand PFAS, Fluorine is the key.
There are different types of organofluorine compounds. These include: fluorocarbons, fluoropolymers, hydrofluorocarbons, fluorocarbenes and perfluorinated compounds (PFAS chemicals). Organofluorine compounds are used in a wide range of applications including oil and water repellents, lubricants, pharmaceuticals, pesticides, refrigerants, plastics, fire fighting foam, fabric stain resistors and reagents in catalysis.
Fluorocarbon production makes up between 40-45% of the Fluorine industry. There are also a host of other derivatives of fluorine used in a variety of industries including metal smelting, ceramics, water fluoridation and petrochemicals. Fluorine gas production is used by the nuclear industry for uranium enrichment.
In the last few years issues regarding PFAS chemicals have been receiving the bulk of media attention and community concern. Some very useful resources particularly from ConsumerNotice.org in the United States let people know how to reduce their exposure to PFAS chemicals and the latest legal updates and lawsuits.
Australia too has seen class actions enacted against the Federal Government in regards to contamination and health risks associated with people living in close proximity military bases where PFAS tainted fire fighting foam was used. Fire fighters have also been at the forefront of demanding justice over the health risks associated with PFAS.
Despite these battles, there's much more to the fluorine industry that many people are unaware of. For instance how many people realise that fluorine is critical in the production of nuclear material for nuclear power plants and nuclear weapons and was also the key chemical causing the depletion of the ozone layer, one of the gravest threats to planet earth. Organofluorine compounds have also been linked to widespread environmental problems including global warming, toxicity and bio-accumulation.
Fluorine is the 13th most abundant element on earth. Fluorine is first utilised by industry primarily through the mining of fluorite. Fluorite (also known as Fluorospar) is used in smelting and the production of enamels and some glasses. It is also increasingly being used in batteries for electric vehicles. The purest grades of fluorite are a source of fluoride* for hydrofluoric acid**, which incidently is the the source of most fluorine chemicals. The largest deposits of Fluorite are in South Africa, Mexico and China. China is the world's largest producer.
(*Fluoride and Fluorine are different chemical compounds. Fluoride is created from salts that form when fluorine combines with minerals in soil or rocks. Fluoride is usually very stable and relatively unreactive, unlike its chemical relative fluorine. **Hydrofluoric acid is a solution of hydrogen fluoride in water. It is made by treating fluorite with sulfuric acid. It is used to make a variety of fluorine-containing compounds, including the pharmaceutical Prozac).
Misuse of Fluorine. A Macro and Micro Environmental Catastrophe?
Chlorofluorocarbons (CFC's) are perfluorinated compounds. Industrial application of chlorofluorocarbons (carbon, fluorine and chlorine mixtures) first started in the early 1930's for use as refrigerants by General Motors and DuPont. These companies formed a company called Kinetic Chemicals who marketed a new product called Freon. Freon's reputation as a potential planet destroyer was confirmed by the discovery of an ozone hole over Antarctica in 1985 caused by CFC particles destroying the ozone layer. This discovery led to the Montreal Protocol in 2010 where production of CFC's was supposed to be eliminated. CFC's were largely replaced with hydrofluorocarbons whose production has been in reduction since 2018 due to its high global warming consequences.
The ozone hole over Antarctica between 2000 and 2018. Rowland and Molina's model for ozone depletion was first published in 1974.
Fluorine & Nukes
Photo: Galerie Bilderwelt/Getty Images. Uranium hexafluoride is used in the process of enriching uranium that produces fuel for nuclear weapons and nuclear reactors. The Manhattan Project during WWII marked the first time that fluorine was produced on an industrial scale.
In simple terms in order to enrich uranium, the metal must be in a gaseous state. The cheapest way to do this is by use of uranium hexafluoride UF6. The preparation of hexafluoride requires elemental fluorine gas and anhydrous hydrogen fluoride. Hydrogen fluoride is made from the reaction of sulphuric acid with fluorspar (CaF2). "Fluorine gas in turn is prepared by the electrolysis of HF. Yellowcake is first converted to uranium tetrafluoride (UF4), using HF, after which the compound is treated with fluorine to yield UF6. After enrichment, the UF6 is reduced to UO2 for use in fuel elements in pellet form".
The K-25 building of the Oak Ridge Gaseous Diffusion Plant built during the Manhattan Project. By far the greatest use of fluorine is in the nuclear industry.
Some other uses
Products to lessen hexafluoride (and other chemical reactivity) also included the invention of a range of coolants, lubricants and polymers that could be made into gaskets, tubing and valve packings. Electrochemical fluorination (ECF) was first reported in 1949, but had been in secrecy due to the Manhattan Project. After World War II, Minnesota Mining and Manufacturing Company (3M) gained access to ECF with the first commercial production of fluorocarbons beginning in 1951. The product line was soon expanded to include: perfluoroethers, perfluoroacyl fluorides*, perfluoroalkanesulfonyl fluorides, and perfluorinated amines. Perhaps the most well known PFAS product 'Scotchguard'* was invented around this time as a water and oil repellent for textile finishes.
The tentacles of the fluorine industry supply chain are massive. Image source: Wikipedia. The global industry is worth about $25billion/year.
Teflon was invented in 1948 by DuPont and was the first commercial use of PTFE (Polytetrafluoroethylene). Teflon then became famous around the world due to its non-stick properties where it could be used as a coating for cookware and a soil and stain repellent for fabrics and textiles. Monomer TFE, used to create polymers used in fluoroplastics was invented around this time as was KelF which was used widely in the aerospace industry due to its chemical and radiation resistance as well as its flammability characteristics.
Teflon fry pan. Image: https://www.scientificamerican.com/article/are-nonstick-pans-safe/ Industries that use teflon include: Food and kitchenware industry (blenders, microwaves, coffee machines, waffle irons, dishwashers, oven ranges etc), chemical manufacturing (coat pipelines, containers, hoses that transport corrosive materials, machinery and tools), construction (coating of electrical wires, gas line pipes etc), automotive and car parts (car coatings, windshield wipers, gaskets etc), Security (explosion detection equipment, locks, keys etc).
Image: ebay Scotchguard has been in use for ~70 years.
PVdF (poly(vinylidene fluoride) was first commericially produced by Du Pont in 1950, with Poly(vinyl fluoride) (PVF) released in 1961 with a major user being the automotive industry to improve paint adhesion. The aerospace industry also used PVF in exterior airplane walls and insulating bags containing glass fibre and air conditioning ducts. In the 1970's ETFE was developed for use in electrical cables and flexible film used in architecture.
Perfluoropolyether (PFPE) fluids were developed in the 1960's for use as lubricants providing high thermal and chemical properties. Flemion was first produced in the late 1970's and used as a ion-exchange membrane used in manufacturing. Longer lasting plastics particularly those used with outdoor coating applications use and metals used industrial applications such as bridges are coated with a product called Lumiflon which means longer life for the coated materials. Fluorocarbon gases started finding application in the semiconductor industry in late 1980s.
Medical fluorine chemistry began in the 1950's. Fluorine substitution (where fluorinated molecules are incorporated into metabolic sequences), make them useful for the use of pharmaceuticals - over 340 pharmaceuticals are regarded as fluro-pharmaceuticals and agricultural chemicals - over 400 agricultural chemicals are considered to be fluro-agrochemicals. Fluoro-pharmaceuticals include: inhalation anesthetics, Non-steroidal anti-inflammatory drugs and anti-bacterial agents.
Fluorinated water containers, are given the fluorine treatment to give the container strength and rigidity. The problem is these containers can also leach PFAS chemicals into the liquid they are holding.
Stop Press: Australian PFAS Map and FoEA PFAS Update
Most of FoE's recent work in the PFAS 'space' has been to investigate the implications of PFAS in the waste water cycle. Between 2021-22 FoE Melbourne produced a number of blogs after investigating information held by numerous Victorian based water authorities. As was predicted the water industry is releasing PFAS tainted water into the environment through waste water. Recycled water is also contaminated as are biosolids which are spread onto farms across Australia. The issue of biosolids and the National Environment Management Plan on PFAS has also been commented on by FoE. Most of our non-existent resources in this space have been monitoring what has been occurring around the country.
The Australian PFAS Map was created by ActionSkills and FoE in 2019 to try and keep track of PFAS issues across Australia. It was not intended to track the Fluorine industry in its entirety, but rather the 'perfluorinated compound' aspect of the industry. Using google statistics its apparent that the site is being well utilised with 4 times as many users as the Australian Drinking Water Map and almost as many as 7 times the users of the Australian Pesticides Map. Over 100,000 people have visited the Australian PFAS map.
Most interest in the Australian PFAS map appears to be centred around NSW and Williamtown Air Force Base. Jandalot Airbase is located in the south of Perth, Allambee Crescent is located at Wodonga, near Bandiana Air Force Base. Sunbury Hi-Quality is based in Victoria and processes contaminated soil. Coode Island refers to an industrial fire in western Melbourne in 1991 where thousands of kilograms of PFAS contaminated fire fighting foam was used. West Bullsbrook refers to another contaminated air base in Western Australia. West Lakes is based in Adelaide and is the location of a new lakes system where sewage waste was used as a soil fill in the 1970's. Pakenham Waste Water facility is where PFAS contaminated water has been detected by South East Water in Melbourne.
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