3M offers compensation of $ 10.3 billion for PFAS contamination in water systems

3M offers compensation of $ 10.3 billion for PFAS contamination in water systems

Pfas chemicals initially seemed to be a good idea. As Teflon, they made cleaning of pots easier from the 1940s. They made jackets waterproof and carpets dirt. Food packaging, fire extinguishing foam and even make-up seemed better to be better with Perfluoralkyl and Polyfluoralkyl substances.

Then tests to detect Pfas in the blood of the people.

Nowadays, Pfas in floors, dust and drinking water all over the world are widespread. Studies indicate that they occur in 98 % of the Americans body and are associated with health problems such as thyroid diseases, liver damage as well as kidney and testicular cancer. There are now over 9,000 types of Pfas. They are often referred to as "chemicals for eternity" because the same properties they make so useful also ensure that they are not broken down in nature.

The 3M industrial giant, which has been producing PFAs for many purposes for decades and has been faced with lawsuits for PFAS contamination, announced on June 22, 2023, a comparison with public water suppliers of $ 10.3 billion to support the financing of tests and treatments. The company assumes no liability in comparison that requires judicial approval. The cleanup could cost a multiple of these costs.

But how do you catch and destroy an eternal chemical?

The biochemist A. Daniel Jones and the ground scientist Hui Li work at the Michigan State University on PfAS solutions and explained the promising techniques that are tested today.

How do Pfas from everyday products get into the water, into the ground and finally in humans?

There are two main exposure routes through which PFAs gets into humans: drinking water and food consumption.

PFAS can get into the ground through the land on the land of organic food, i.e. mud from wastewater treatment, and out of landfills. When contaminated organic resorts are applied as fertilizers in agricultural fields, pfas can get into the water as well as in crops and vegetables.

For example, farm animals can absorb PfAs about the plants they consumed and the water they have drunk. Cases of increased PFAS values ​​for beef and dairy cows were reported to Michigan, Maine and New Mexico. How great the potential risk for humans is still largely unknown.

Scientists of our research group at the Michigan State University work on materials that are added to the soil and would prevent plants from being recording pfas, but would leave Pfas in the ground.

The problem is that these chemicals are everywhere and there is no natural process in the water or floor that effectively breaks them down. Many consumer products are loaded with PFAs, including make-up, dental floss, guitar strings and ski wax.

How do the PFAS contamination now remove renovation projects?

There are methods to filter them out of the water. For example, the chemicals stick to activated carbon. However, these methods are expensive for large-scale projects and you still have to do without the chemicals.

Near a former military base near Sacramento, California, there is, for example, a huge activated carbon tank, which absorbs about 1,500 gallons contaminated groundwater per minute, filters it and then pumps into the surface. This renovation project cost over $ 3 million, but it prevents PFAs from reaching the drinking water used by the municipality.

The US environmental protection authority has proposed to introduce legally enforceable regulations for the maximum values ​​of six PFAS chemicals in public drinking water systems. Two of these chemicals, Pfoa and Pfos, would be recognized as individual dangerous chemicals, whereby official measures would be implemented if the content of one of these chemicals exceeds 4 parts per billion, which is significantly below the previous guidelines.

Filtering is only a step. As soon as Pfas is collected, you have to dispose of activated carbon loaded with PFAs, and Pfas continues to move. If you bury contaminated materials on a landfill or elsewhere, Pfas are finally drained. So it is important to find ways to destroy it.

What are the most promising methods that scientists have found to reduce Pfas?

The most common method for destruction of PFAS is the combustion, but most PFAs are remarkably resistant to combustion. That is why they are included in fire foams.

In Pfas, several fluoron atoms are bound to a carbon atom, and the binding between carbon and fluorine is one of the strongest. To burn something, you usually have to break the bond, but fluorine cannot be solved from the carbon. Most PFAs are completely decomposed in combustion temperatures around 1,500 degrees Celsius (2,730 degrees Fahrenheit), but it is energy -intensive and suitable incineration plants are rare.

There are several other experimental techniques that are promising, but have not been extended to the treatment of large amounts of chemicals.

A group in Battelle has developed over -critical water oxidation to destroy PFAs. High temperatures and pressures change the condition of the water and accelerate the chemistry in a way that can destroy dangerous substances. However, the scaling remains a challenge.

Others work with plasmaractors that use water, electricity and argongas to break down PFAs. They are quick, but also not easy to scale.

What will we probably see in the future?

A lot will depend on what we learn about where the PfAS exposure of humans comes from.

If the exposure is mainly via drinking water, there are other methods with potential. It is possible that it will eventually be destroyed by electrochemical methods at household level, but there are also potential risks that still need to be understood, such as the conversion of usual substances such as chloride into poisonous by -products.

The great challenge in the renovation is to ensure that we do not make the problem worse by releasing other gases or creating harmful chemicals. People have been trying to solve problems for a long time and make things worse. Refrigerators are a good example. Freon, a hydrocarbon fluorecloal fabric, was the solution to replace toxic and flammable ammonia in refrigerators, but then it caused ozone mining in the stratosphere. It was replaced by hydrocarbons that now contribute to climate change.

If there is a lesson to learn, then that we have to think through the entire life cycle of products. How long do we really need chemicals to be durable?

This is an updated version of an article that was originally published on August 18, 2022.

a. Daniel Jones, professor of biochemistry, Michigan State University and Hui Li, professor of environmental and soil chemistry, Michigan State University