Kemira wants to shed light on the subject and share some promising news. In our recently published study, we prove that commercially available water treatment chemistry ─ solutions that are commonly used for drinking water production and wastewater purification ─ can effectively remove microplastics from water. That could prevent you from drinking microplastics next time you take a sip.
Plastic is everywhere. It’s hard to imagine modern life without it. At the same time, about half of the 360 million tons of plastic produced each year is used for mere moments. It doesn’t just disappear after we’re through with it. Much of it will sit as waste on our planet for several hundred years.
That’s only the visible part of the problem. At less than 5 mm in size, microplastics are difficult to see but widespread. These tiny plastic particles have made their way into every corner of the world – through air, water, soil and into living things.
But where do they come from? Microplastics have two origins. First, they come from larger plastics that break down into smaller and smaller pieces through weathering and decomposition. Alternatively, some microplastics are manufactured and intentionally added to a range of products such as toothpaste, face scrubs and peels, as well as paints and agricultural fertilizers. Ultimately, they can end up in the aquatic environment through urban sewage, street run-off and other kinds of leaching.
There is limited information about the risks of microplastic to human health. Based on current knowledge, the World Health Organization (WHO) suggests that microplastics in drinking water don’t appear to pose a risk at current levels. However, some scientists and health experts remain concerned.
Professor Rolf Halden, Director of the Biodesign Center for Environmental Health Engineering at Arizona State University states, “Unfortunately, in terms of human exposure to plastics we know the least about those plastic pollutants that likely pose the greatest health risks: microplastics and nanoplastics in the human body. Among hundreds of papers dealing with plastic pollution, only a few consider the tiny particles that are capable of crossing from the gastrointestinal tract into the human blood stream.” At a recent press conference of the American Chemical Society (ACS), Halden and his team presented research with an alarming conclusion. “In every human sample we examined, our team has found monomers of both bisphenol A (BPA) and its chemical cousin, tetrabrominated BPA,” he said. BPA is a key building block of polycarbonate plastic. This type of plastic is an ingredient in a variety of common consumer goods like re-usable plastic tableware, plastic bottles, sports equipment, CDs and DVDs.
The good news is that modern water treatment may help. Many types of water treatment plants are highly effective in removing particles that are similar to microplastics in size and other properties.
Moreover, a new study from Kemira recently verified that coagulants, a type of water treatment chemistry, can remove up to 99.4% of the microplastics in wastewater. Coagulants are special salts containing iron or aluminum. They react with tiny particles in the water, clumping them and making them easier to separate. It turns out that coagulants also successfully clump microplastics.
We knew that coagulants generally do a very good job in removing solids from drinking water and wastewater
says Outi Grönfors, Principal Scientist of Kemira’s Water Treatment R&D Team. “Nevertheless, we are delighted to scientifically prove that coagulants remove these very tiny and potentially harmful microplastic particles.”
To run the study, Kemira’s team had to quantify the tiny pieces of plastic in each wastewater sample. That included the difficult task of identifying microplastics versus other impurities. The researchers developed their own measuring method which can detect microplastic particles in real wastewater, even particles measuring less than 0,01 mm.
Grönfors explains that optimal chemistry selection and dosage, as well as setting the correct process conditions, will be critical for successful microplastic removal technology at scale.
It is clear that plastic does not belong anywhere in the water cycle. It shouldn’t be in our water resources, like rivers and reservoirs, nor should be any microplastics in drinking water. Unfortunately, there is already an enormous amount. And, even if all plastic production stopped right now, the current issue won’t just go away.
That should underscore the importance of state-of-the-art water treatment technology, as well as full enforcement of existing water regulations. Today most modern water treatment facilities already use coagulants to remove particles, algae and bacteria from surface water to make it safe to drink. By optimizing this type of water treatment methods, microplastics can also be efficiently removed.
Let’s make sure water is safe to drink. Chemistry can help. Quality water is plastic-free water.