Perfluorooctanoic Acid (PFOA) is a synthetic perfluorinated compound belonging to the PFAS (Per- and Polyfluoroalkyl Substances) family. It was widely used in non-stick coatings, waterproof textiles, and industrial processes until it was banned or restricted in many countries due to its environmental persistence, bioaccumulation, and toxicity. PFOA has been classified as a human carcinogen (Group 1 IARC, 2020), making it one of the most hazardous chemicals in its class.

1. Chemical structure and properties

PFOA is characterized by a perfluorinated eight-carbon chain (C8) with a carboxyl (-COOH) functional group. This structure provides:

• High chemical and thermal resistance → does not degrade easily.
• Hydrophobic and lipophobic properties → repels water, grease, and oils.
• High surface activity → used in industrial processes as a surfactant.

Due to these properties, PFOA is highly persistent and accumulates in the environment and living organisms.

2. Industrial and consumer applications

Before its regulation, PFOA was used in numerous applications, including:

a. Teflon production and non-stick coatings

• Used to manufacture PTFE (Polytetrafluoroethylene, known as Teflon), found in non-stick cookware, pans, and kitchen utensils.
• Present in coatings for cables, gaskets, and industrial seals.

b. Waterproof and stain-resistant textiles

• Treatments for technical clothing, shoes, tents, and upholstery.
• Used in furniture fabrics and carpets to make them stain-resistant.

c. Food packaging

• Applied to grease-resistant paper for fast food wrappers, microwave popcorn bags, and oil-resistant packaging.

d. Firefighting foams

• Key ingredient in AFFF (Aqueous Film-Forming Foam) used to extinguish hydrocarbon fires (military bases, airports).
• One of the leading causes of groundwater contamination.

e. Industrial and electronics applications

• Used in semiconductors, printed circuit boards, and industrial coatings.
• Applied to metal plating processes to reduce surface tension.

3. Environmental and health impacts

a. Persistence and bioaccumulation

PFOA is considered a "forever chemical" because it does not naturally degrade. It has been detected in:

• Drinking water and groundwater, especially near industrial sites and military bases.
• Soil and sediments → persists for decades.
• Marine organisms, fish, mammals, and birds, accumulating in the food chain.
• Human blood and tissues, with an average half-life of 3-5 years.

b. Health effects of PFOA exposure

Epidemiological studies have linked PFOA exposure to serious health risks, including:

1. Cancer

• Increased risk of kidney and testicular cancer.
• Possible correlation with prostate, pancreatic, and liver cancer.
• Classified as a human carcinogen (Group 1 IARC, 2020).

2. Reproductive and developmental toxicity

• Reduced fertility in both men and women.
• Low birth weight and developmental issues.
• Neurobehavioral disorders in children exposed during pregnancy.

3. Metabolic disorders

• Increased LDL cholesterol and risk of cardiovascular disease.
• Type 2 diabetes and lipid metabolism disruptions.

4. Endocrine disruption

• Thyroid dysfunction, potentially leading to hypothyroidism.
• Interference with steroid and sex hormones.

5. Immune system effects

• Reduced vaccine efficacy and increased susceptibility to infections.
• Possible link to autoimmune diseases.

4. Regulations and bans

Due to its toxic effects, PFOA has been progressively banned or restricted worldwide:

• 2019 → Listed under the Stockholm Convention on Persistent Organic Pollutants (POP), leading to a global phase-out.
• United States (EPA, 2023) → Drinking water limit reduced to 4 parts per trillion (ppt).
• European Union (REACH, 2020) → Full ban on production and use, with some exemptions for critical applications.
• Canada, Japan, Australia → Strict restrictions and active environmental monitoring.

Despite these bans, PFOA remains in the environment due to historical contamination and the use of similar replacement substances.

5. How to reduce PFOA exposure?

• Avoid non-stick cookware and utensils with damaged or overheated Teflon.
• Limit the use of products treated with waterproof or stain-resistant coatings (carpets, furniture, outdoor gear).
• Avoid food packaged in grease-resistant wrappers.
• Filter drinking water with activated carbon or reverse osmosis systems.
• Choose PFAS-free alternatives for cosmetics, household products, and food packaging.

6. Conclusion

PFOA is one of the most toxic and persistent chemicals ever produced, with carcinogenic, immunotoxic, and metabolic effects. Although it has been banned in many countries, contamination remains widespread globally. Ongoing regulation and research into safer alternatives are essential to protect public health and the environment.