All you need to know about PFOS and PFAS

All you need to know about PFOS and PFAS

Recently, the topic of PFAS has gained widespread interest. With the publication of research reports and associated media coverage, people have come to a startling realization that many products in their lives contain PFAS. PFAS is a general term for a group of chemicals. In particular, PFOS is a type of PFAS that was widely used in the past and became the first to be restricted, because it raised the greatest health concerns of all PFAS.I It also remains in the environment for a longer time. The article will explain what PFAS and PFOS are, where these chemical substances are used, and when we are most vulnerable to them. It will also propose suggestions for avoiding PFAS and PFOS exposure.

What are PFOS and PFAS?

PFAS is an acronym for per- or polyfluoroalkyl substances, a universal term for thousands of fluorinated compounds that offer water and oil-repellent characteristics. When oil drips onto a PFAS coating, it will form oil droplets that remain on the surface without soaking into the fiber, which is protected by the PFAS coating. Consequently, PFAS are often used to process products such as waterproof clothing/boots, stain-resistant blankets, and pizza boxes. Because they do not break down easily and remain in the environment for a long time, scientists refer to them as “forever chemicals”.

PFOS are a type of PFAS with a long-chain structure which allows them to offer better water- and oil-repellency than short-chain PFAS. However, due to their excellent stability, they take longer time to break down and stay in the human body more easily, giving rise to health concerns. Current studies have proven that PFOS may be the cause of neonatal aberrations, thyroid diseases, neurological diseases, cardiovascular diseases, and cancer.

In 2000, 3M, a company that has used PFOS extensively, voluntarily phased it out. In 2009, PFOS was listed in the Stockholm Convention on Persistent Organic Pollutants, which controls international hazardous chemical substances. As PFOS has been controlled and banned worldwide, manufacturers have looked to short-chain PFAS to replace PFOS. However, an increasing amount of research has proven that short-chain PFAS also have health concerns, and therefore that people can only ensure their health by avoiding perfluorinated chemicals (PFCs).

Where can we find PFOS and PFAS?

Since PFOS is listed as a category 2 controlled chemical substances in the Stockholm Convention on Persistent Organic Pollutants, it has been banned in over 150 member countries so is unlikely to be found in products manufactured today. PFOS will only appear in certain specific applications and environments. However, because some countries have yet to pass legislation to control PFOS it is not certain whether they are still using PFOS to manufacture products. Therefore, besides places where PFOS is known to still exist, the article will list some products that were originally manufactured using PFOS but have now been replaced by other short-chain PFAS alternatives. These products containing PFAS still carry the risk of being manufactured using PFOS.

Fire extinguishers

The firefighting foam in fire extinguishers is produced using PFOS as a surfactant. It is gradually being replaced by other short-chain PFAS or silicone-based surfactants that do not contain fluorine. At present, PFOS can still be found in old fire extinguishers or fire extinguishers in airports and military facilities that have special requirements. This PFOS will be released when the firefighting foam is used, thereby harming the environment.

Groundwater near airports and military facilities

Since airports and military facilities use firefighting foam containing PFOS, it will end up in the surrounding environment when an accident or fire drill takes place. After being washed away by rain, PFOS will contaminate the surrounding land and groundwater sources. PFOS can be detected in crops cultivated near airports and military facilities, and in groundwater used for drinking.

Auto parts

PFOS is an essential additive for controlling smoke in the electroplating process. Since it cannot completely replace chromium raw materials at present, a lot of money must be invested in ventilation systems to reduce smoke and protect workers’ health. Since we are unclear of the actual product manufacturing conditions, it is impossible to determine if PFOS is used in the production of auto parts.

Medical devices

Medical equipment requires high precision and accuracy, and PFOS is used as the raw material for producing contrast agents and radiopaque catheters because of its unique durability and non-reactivity. Although substitutes are being sought, PFOS is still widely used in various medical devices today.


PFOS are found in the transfer belt, roller, and fixing device of the printer, being used in sealants and adhesives. Due to the low concentration and complex composition, there is little research on substitutes or on any impact on the human body.

Ant killers

PFOS is an essential material for producing sulfluramid, and approximately 10% of sulfluramid degrades to PFOS after use. It is also widely used in pesticides. Currently, the EU has banned the use of PFOS in pesticide production, but it continues to be used by some countries.


The semiconductor manufacturing process involves exposure, development, and etching. PFOS is used as an anti-reflective coating and is also an ingredient of the etchant. Since developing a new photoresist system for semiconductors will require millions of dollars and many years, there are currently no alternative solutions available.

Color photos

PFOS are used as a thin film coating for color photos to maintain consistent coating thickness, mitigate static electricity, reduce friction, and prevent staining. The cost of the current alternative is extremely high, as it may cost USD25 million to replace 1kg of PFOS.

LCD screens

LCD screens require precision optical etching using PFOS as the etchant. Since short-chain PFAS or fluorine-free alternatives are ineffective in decreasing surface tension, there are currently no other substitutes available.

Aviation hydraulic fluid

PFOS is added to hydraulic fluid in the aviation industry to prevent corrosion of aircraft parts. Since only a small amount is added and it is used in closed mechanical systems, there is relatively little information about substitutes or any impact on people’s health.

When might we be exposed to PFOS and PFAS?

PFAS are everywhere, and we are almost constantly exposed to them in life. As a type of PFAS with higher toxicity, despite its use being restricted, we are still vulnerable to PFOS exposure in certain scenarios, including the following eight situations:

Working in a factory

Some manufacturing industries cannot avoid using PFOS, examples include semiconductors yellow light process, LCDs, auto parts electroplating, or pesticides. Workers in these sectors may be exposed to PFOS to some degree, so should wear protective clothing to prevent direct exposure.

During fires or fire drills

Most of the firefighting foam produced in the past contained PFOS. We are uncertain whether foam in use now still contains PFOS, but if it does, it may be released to the surrounding environment when sprayed, exposing people at the scene to PFOS.

Tap water

According to the latest research report by the U.S. Geological Survey (USGS), PFAS can be detected in about 45% of the country’s drinking water, with PFOS is also detected. As a result, we are exposed to PFOS when drinking or coming into contact with water.

Receiving medical treatment

Many medical devices require PFAS to improve their functionality and reduce costs. For instance, adding PFAS to medical implants helps combat infection, friction, and thrombosis, while PFAS coatings on medical gowns or partition curtains can prevent infection and the spread of diseases. Therefore, PFAS can be found everywhere in medical facilities, and the presence of PFOS is also occasionally detected. It is important to stay healthy and avoid unnecessary medical treatments, in order to prevent being exposed to PFAS.

Wearing special clothing

Firefighting suits, medical gowns, outdoor water-repellent jackets, stain-resistant work pants, and raincoats may contain PFAS used as surface treatment agents, thereby exposing us to PFAS.

Eating freshwater fish

Freshwater fish may be captured downstream of factories producing PFAS-related products. Since we are unable to determine if PFAS levels in rivers exceed the limit, and PFAS in water may accumulate in the fish, eating freshwater fish increases the risk of exposure to PFAS.

Car detailing

Waxes, polishes, and paints used for car detailing contain PFAS to form a protection film against haze, stains, dirt, and static electricity. In some products, PFOS are used, thus it is important to check if the car detailing chemicals you use specify that they are PFAS-free, otherwise, it is better to minimize car detailing activities.

Takeout food

Paper lunch boxes are used to hold takeout food often contain PFAS coating, to give the paper water- and oil-resistant properties. This coating can be transferred to the food, exposing us to PFAS.

What impacts do PFAS and PFOS have on our health?

The scientific community is in the process of studying the impact of PFAS and PFOS on our health. Some potential impacts are outlined below:

Reproductive system

PFAS disrupt reproductive hormones and decrease our reproductive ability.

Thyroid gland

PFAS are endocrine-disrupting chemicals (EDCs), these that can affect thyroid hormone production, cause metabolic problems, and cause diseases such as diabetes.

Nervous system

PFAS can generate neurotoxicity, leading to chronic psychosis.

Cardiac vessels

PFAS will cause abnormal platelet function and increase the chance of thrombosis.


As mentioned above, since PFAS affect various systems in the human body, the chances of kidney cancer, testicular cancer, breast cancer, ovarian cancer, endometrial cancer, prostate cancer, and thyroid are increased considerably.

For more details on the impact of PFAS on the human body and relevant studies, please read the article: “How to avoid PFAS? 12 Ways to Reduce Your Exposure to PFAS”.

How to avoid exposure to PFOS and PFAS in our lives?

Install activated carbon or RO water filtration systems

Installing activated carbon or RO water filtration systems at home is an effective way to remove PFAS and PFOS from water, allowing us to reduce our exposure to PFAS and PFOS in water we use every day and drinking water. At the same time, it will also help improve the water quality of the overall environment.

Consume saltwater fish instead of freshwater fish

Fish is rich in omega-3 fatty acids and high-quality proteins. With identical protein intake, fish contains less cholesterol and fat than other red meats such as beef and pork. However, since chemicals in the water accumulate in animals’ fatty tissues, if the fish is from waters containing PFAS, the chemicals will end up in our bodies through ingestion. Although there are PFAS in seawater, saltwater fish is still a safer choice compared to freshwater fish, which may have been exposed to direct contamination.

Reduce outdoor activities

For the sake of convenience, we are forced to choose outdoor clothing and products containing PFAS in order to enjoy their water- and stain-resistant benefits. When exposed to rainwater, wind, and sand, PFAS will end up in the environment. To avoid exposure to PFAS, it is best to reduce outdoor activities before suitable alternative materials are developed!

Bring your own stainless-steel tableware

According to numerous studies, various types of straws and food packaging we come across daily, whether they are made of paper, bamboo, plastic, or glass, contain traces of PFAS. The only material that has not been found to contain PFAS is stainless steel Therefore, bringing your stainless steel tableware when eating out is the most effective way to avoid PFAS exposure.

Use renouvo’s PFAS-free food packaging collection

Do you feel that stainless steel tableware is cumbersome and difficult to clean? Perhaps you can consider renouvo’s straws, tableware, and food packaging! renouvo’s products are made of bagasse, a natural agricultural waste, and they offer both disposal and reusable options. These products are light, water- and oil-resistant, and have passed PFAS inspections to ensure that no PFAS have been added and that there is no contamination. After use, they can be decomposed under room temperature by following instructions in the home compostable certification, which not only prevents exposure to PFAS but is also eco-friendly.

Join the initiative to refuse PFAS

Although countries around the world are devising strategies to control PFAS, such as stipulating PFAS standards for drinking water and banning the use of all PFAS, more public support is needed to passionately promote the passing of legislation to stop PFAS from entering the environment, and to think about how to progressively remove PFAS from the environment.

Why renouvo care about PFOS and PFAS?

While pursuing a better quality of life, people have created chemical substances that did not previously exist in the environment. Chemicals such as microplastics, PCBs, and PFAS take an extremely long time to break down, and when they enter the environment they follow the water cycle to infiltrate every part of the world, affecting everyone’s health. renouvo hopes to reduce these long-term burdens on the earth, which is why all of its products are plastic- and PFAS-free. At the same time, it aspires to cater to people’s needs and help them to positively change the future of the earth at the lowest cost.