Per- and Polyfluoroalkyl Substances (PFASs)

Per- and Polyfluoroalkyl Substances (PFASs) are toxic, man-made, hazardous chemicals that have dangerous effects on the environment and our health. They are a large family of fluorinated chemicals that have partially or completely fluorinated carbon chains of varied lengths. PFHxS, PFOA and PFOS are the three subgroups of PFASs currently listed under the Stockholm Convention as industrial POPs.

Production and uses of PFASs

The PFAS family is composed of thousands of synthetic organic chemicals. PFASs were developed from the 1940s by the chemical industry. To date, more than 4,700 Chemical Abstracts Service (CAS) numbers have been identified which can be associated with a large variety of PFASs that may have been on the global market and in the environment (OECD 2018). Their common point is they are composed of a very stable structure which gives them properties highly sought after in industry: they resist very high heat, protect surfaces from water, grease or friction, and have fire-retardant and stain-resistant properties.

PFASs are used in the chemical industry including in Polytetrafluoroethylene (PTFE) production, in the metal plating industry, in the photo imaging industry, and in the semi-conductor industry.

PFAS in everyday consumer goods

A wide variety of everyday consumer goods are produced with PFASs: stain resistant carpets and upholstery, water-repellent clothing, fire-fighting foam, papermaking, printing inks, sealants, the interior coating of non-stick cookware, greaseproof food packaging, biocides household agents such as cleaning agents and impregnation sprays. Recent studies have found PFAS in personal hygiene and care products such as cosmetics, dental floss, toilet paper. Plastics may contain PFAS.

Among the thousands of PFASs being produced and used, there are many overlooked ones that are structurally similar to PFOS, PFOA, or their precursors, and are produced in high volumes (Wang et al. 2017).

Exposure to PFASs

People can be exposed to PFAS by:

Working in firefighting or in chemicals manufacturing and processing
Drinking or eating liquids or food contaminated with PFAS
Swallowing dust contaminated with PFAS
Breathing air containing PFAS
Using products made with or packaged in materials containing PFAS

Hazardous effects of PFASs

Due to PFASs long-term persistent accumulation, humans, wildlife and the environment continues to be exposed long after these compounds are released into the air, water and soil. PFAS are highly mobile in air, water and soil and are mostly persistent. They do not degrade - or only partially. Their lifespan is up to several thousand years, hence their nickname "forever pollutants". The health risks from PFAS have been known since the 1990s, long-chain PFASs have been widely recognized as contaminants of high global concern by the OECD in 2013. They have been linked to cancer, reproductive harm, immune system damage and other serious health problems, even at low levels.

PFASs health impatcts

PFOS affects the liver, kidney, thyroid, fecundity, leading to cancer formation.

Major health issues such as kidney cancer, testicular cancer, thyroid disease, pregnancy-induced hypertension, high cholesterol have been linked to PFOA.

Effects of PFHxS in humans are found to influence on the nervous system, brain development, endocrine system, and thyroid hormone.

PFOS, PFOA and PFHxS are transferred to foetus through cord blood and to infant through breast milk (UNEP 2016b, 2018). Exposure to PFOA and PFOS over certain levels may result in developmental effects to foetuses or breastfed infants (UNEP 2016b; US EPA 2016a, 2016b).

PFASs and the Stockholm Convention

Perfluorooctane sulfonic acid (PFOS) listed in Annex B (restriction) since 2009 is both intentionally produced and an unintended degradation product of related anthropogenic chemicals. The current intentional use of PFOS is widespread and includes in electric and electronic parts, as fire-fighting foam, photo imaging, hydraulic fluids, and textiles. PFOS is still produced in several countries. Its acceptable uses include as an active ingredient in insect bait to control leaf-cutting ants, in closed-loops systems in metal plating and as fire-fighting foam.

Perfluorooctanoic acid (PFOA) is listed in Annex A (elimination) since 2019. PFOA are used widely to produce non-stick kitchen ware, and food processing equipment. Unintentional formation of PFOA is created from inadequate incineration at moderate temperatures of municipal solid waste within inappropriate or open burning facilities.

In 2019, at the Second session of the International Conference on Chemicals Management (ICCM2), SAICM stakeholders identified managing PFASs and the transition to safer alternatives as an issue of concern.

The 10th meeting of the Conference of the Parties in 2022 listed perfluorohexane sulfonic acid (PFHxS) widely used in fire-fighting foam, carpets, and non-stick cookware.

Perfluorocarboxylic acids (PFCAs) used in a range of applications, including in coating products, fabric/carpet protectors, textile impregnation agents and firefighting foams is a candidate POPs proposed for listing under the Stockholm Convention.

See the Interactive timeline of POPs listed under the Stockholm Convention.

GMP Dashboard

The UNEP/GEF Global Monitoring project measures concentrations of POPs.

The matrix "water" is included for the first time, 22 countries measure PFAS (PFOS, PFOA and PFHxS) concentration in water. See the results in the interactive dashboard.

Global acceleration of action

NGOs have measured 'forever chemicals' in the blood of a dozen European politicians. Among them is former European Commission vice president Frans Timmermans, who is calling for a ban on these substances. Le Monde, 1 February 2024.

In France, the metropolis of Lyon announced in March 2023, the launch of a major survey to study the presence of PFAS, around the Arkema and Daikin Chemical factories, just downstream of Lyon, in the commune of Pierre Bénite where traces of the POPs have been found in fish, breast milk and eggs.

In March 2023, The United States administration announced the upcoming introduction of standards to limit the level in running water, a first at the federal level. "What started as a so-called miracle, a technological breakthrough thought for its practicality, quickly degenerated into one of the most pressing public and environmental health problems of the modern world”. Michael Regan, head of the US Environmental Protection Agency.

At the initiative of Germany, the Netherlands, Denmark, Norway and Sweden, the European Chemicals Agency is opening a consultation in March 2023 with a view to a virtual ban on the production, import, sale and use of PFAS in the territory of the European Union, in the name of the precautionary principle.

At the beginning of 2023, a survey carried out by eighteen European media, including Le Monde, identified 17,000 contaminated sites in Europe and the United Kingdom, including 2,100 at levels dangerous to health. Often near old factories.