Restricted substances -PFOS and PFOA

PFOS - Perfluoroctane sulphonates What are they? These are fluorinated anions which are a member of the family of chemicals known as perfluoroalkyl sulphonate substances (PFAS). The majority of PFOS-related substances are polymers of high molecular weight in which PFOS is only a fraction of the polymer and final product.  Where are they used? Historically these chemicals were used in the following applications:

• Carpets
• Leather/apparel
• Textiles/upholstery
• Paper and packaging
• Coatings and coating additives
• Industrial and household cleaning products
• Pesticides and insecticides

3M used to be the major global producer of PFOS and their voluntary withdrawal from the manufacture of PFOS (since 2001) has resulted in the phase out of the use of PFOS-related substances in consumer applications within the UK.  Although 3M have withdrawn from manufacture of PFOS, they are still available commercially as salts, derivatives and polymers. Their major use is in grease, oil and water resistance treatments for textiles, carpets, paper and other coatings. Smaller volume uses are in chromium plating, photography, photolithography, fire-fighting foams and hydraulic fluids for aviation. What are the risks? The Association for Economic Co-operation and Development (OECD) has carried out an assessment of the risks associated with the use of PFOS, both for human health and for the environment. With regard to human health, PFOS are persistent, bio-accumulative and toxic in mammals. There is a statistically significant association between PFOS exposure and bladder cancer, along with other health effects.  On an environmental basis, PFOS are persistent and bio-accumulative. They are highly toxic to honey bees and bio-concentrates in fish, surface water and sediment, in wastewater treatment plant effluent, sewage sludge and in landfill leachate. Restrictions PFOS have been classified by the Scientific Committee on Health and Environmental Risks (‘SCHER') as very persistent, very bioaccumulative and toxic. PFOS are also believed to have a potential for long range environmental transport and to produce adverse effects and to fulfill the criteria for ‘persistent organic pollutants' (POPs) under the Stockholm Convention. The SCHER recommended that further scientific risk assessment of PFOS be conducted. ‘Directive 2006/112 of December 12, 2006, amending for the thirtieth time Directive 76/769 on the approximation of the laws, regulations and administrative provisions of the Member States relating to the marketing and use of certain dangerous substances and preparations (perfluorooctane sulfonates)' (the ‘Directive') applies to perfluorooctane sulfonates (PFOS) with the chemical formula C8F17SO2X, where X can be OH, metal salt (O-M+), halide, amide, and other derivatives including polymers. The Directive imposes two restrictions relative to PFOS:

• PFOS may not be placed on the market or used as a constituent of preparations in a concentration equal to or higher than 0.005% by mass
• Semi-finished products or articles, or parts thereof, may not be placed on the market if the concentration of PFOS is equal to or higher than 0.1% by mass calculated with reference to the mass of ‘structurally or microstructurally distinct parts that contain PFOS'.

In respect of the latter restriction, one of the recitals to the Directive states that it should cover ‘all the products and articles to which PFOS are intentionally added, taking into account that PFOS may have been used only in some distinct parts or in coatings of certain products and articles, such as textiles.' A further recital clarifies that the Directive should only restrict new products and not apply to products already in use or on the second-hand market. The European Commission has published a proposal for implementation of a new directive. This relates to restrictions on the marketing and use of perfluoroctane sulphonates and would be an amendment of the Council Directive 76/769/EEC. PFOA - perfluoroctanoic acid What is it and where is it used? PFOA (C8HF15O2) is a completely fluorinated organic chemical that can be produced synthetically or through the degradation or metabolism of other fluorochemical products. PFOA is primarily used as a reactive intermediate, where its salts are used as processing aids in the production of fluoropolymers and fluoroelastomers (used as non-stick coatings) and in other surfactant uses.  What are the risks? PFOA persists in the environment and accumulates in human and animal tissue. It is also probably going to be classified as a ‘likely human carcinogen'. The situation Perfluorooctanoic acid (PFOA) and its salts are suspected to have a similar risk profile to PFOS. Therefore, the European Union's Directive has charged the Commission to keep under review the ongoing risk assessment activities and the availability of safer alternative substances or technologies related to the uses of PFOA and related substances. It is to propose all necessary measures to reduce identified risks, including restrictions on marketing and use, in particular when safer alternative substances or technologies, that are technically and economically feasible, are available. The US Environmental Protection Agency (EPA) has ‘invited' eight chemical manufacturers to phase out emissions of this compound. As of the beginning of March 2006, commitment letters were received from all of the invited companies (DuPont, 3M, Arkema, Asahi Glass, Ciba Speciality Chemicals, Clariant, Daikin and Solvay). In order to participate in the scheme the companies have had to agree to the following actions: 1)  To commit to achieve, no later than 2010, a 95% reduction, measured from a year 2000 baseline, in both facility emissions to all media of PFOA, precursor chemicals that can break down to PFOA, and related higher homologue chemicals and product content levels of PFOA, precursor chemicals that can break down to PFOA, and related higher homologue chemicals. 2)  To commit to working toward the elimination of PFOA, PFOA precursors, and related higher homologue chemicals from emissions and products by five years thereafter, or no later than 2015. Whilst this is a purely voluntary agreement with the EPA, it mirrors a similar action that occurred in 2000 related to PFOS (when 3M announced a voluntary withdrawal from PFOS based technologies). Therefore, perhaps it should not be unexpected if legislation is proposed related to PFOA some time in the future. Conclusions The European Commission's objectives now are (i) to phase out the exempted uses of PFOS as soon as the use of safer alternatives is technically and economically feasible, (ii) to ensure that derogations are continued only for essential uses for which safer alternatives do not exist and where the efforts undertaken to find safer alternatives have been reported on and (iii) to ensure that releases of PFOS into the environment have been minimised, by applying best available techniques. Implementation date for this Directive is June 27, 2008. Analysis of these compounds is highly specialised and BLC Leather Technology Centre is one of only a few laboratories able to offer this testing to customers. For further information contact BLC Leather Technology Centre Ltd on info@blcleathertech.com