Polski
Expensive water filtration systems are not the only way to improve the quality of home beverages. According to a recent study by Chinese researchers, microplastics in tap water can be effectively eliminated through a very simple process – boiling. While this method has its limitations, it can fundamentally improve health security, especially among less affluent populations.
Ubiquitous microplastics
Plastics have revolutionized the economy and the daily lives of people around the world. However, one of their most important qualities – durability – has proven to be a double-edged sword. The decomposition process of plastic that has ended up in a landfill can take up to hundreds of years. During this time, the raw material breaks down into smaller and smaller particles, which are easier to penetrate into the environment.
Microplastics are considered to be particles with a diameter of less than 5 mm. From landfills, they easily infiltrate surface water, into rivers, streams, seas and oceans. For years we have been hearing alarming reports about their elevated concentrations in the world’s bodies of water – high values have so far been reported in the Great Lakes of North America and the Mediterranean Sea, for example. And since the world is really a system of interconnected vessels, we end up finding microplastics in tap water.
The problem does not end there, of course. Synthetic particles in increasing quantities are observed in the soil, air and even clouds. To make matters worse, under the influence of time and external factors, such as. light, heat or oxidation, the microplastic is further fragmented, transforming into nanoplastics, or particles smaller than 1 μm in diameter. Their ability to penetrate deep into plant, animal and human tissues is of high concern.
Boiling reduces microplastics in tap water
The study published on February 28 of this year. in the scientific journal Environmental Science & Technology Letters sheds new light on the possibility of eliminating unwanted particles in drinking water. And the issue is urgent, since 2016. Studies proving an imminent threat to public health are proliferating. Nine studies over five years identified microplastics in tap and bottled water, among others. In Germany, Denmark, France, Italy, Japan and the United States.
Until now, the elimination of microplastics from drinking water has been carried out by filters operating on the principle of reverse osmosis, distillation or ultrafiltration. Each of these systems is effective, but involves a significant increase in the cost of living, which is virtually impossible for many households. Meanwhile, researchers in Guangzhou, China, have found that a cheap and easy boiling process effectively reduces the amount of microplastics in tap water. In Asia, the custom of boiling tap water is by no means a novelty. Eastern societies eliminate potential biological pathogens and some chemical contaminants this way. In China, it is even practiced to drink hot water for health.
Hard or soft water? The fundamental difference
Researchers from Guangzhou decided to study how boiling water affects the presence of three of the most common plastics in water: polystyrene, polyethylene and polypropylene. To do this, they boiled tap water for five minutes and then let it cool. It turned out that the calcium carbonate particles present in the tap water precipitated and deposited on the microplastic particles, inactivating them. According to Eddy Zeng, who headed the study in question, most of the slowly floating plastic particles are reduced to a stony sludge this way, and the rest can be strained through an ordinary coffee filter.
Hard water with a calcium carbonate concentration of more than 120 mg/L was used for the study. The cooking process succeeded in eliminating at least 80 percent. Polystyrene, polyethylene and polypropylene microparticles with a size of 0.1-150 μm. This is a very optimistic result, proving that households can easily treat drinking water, reducing the harmful potential of microplastics. Skeptics point out, however, that the study appears to have serious practical limitations.
Well, microplastics in tap water occur regardless of its hardness. Boiling soft tap water, which does not contain enough calcium carbonate, you will not get such results. A test repeated on water samples with a concentration of less than 60 mg of CaCO3 per 1 L eliminated only 25 percent. microplastics. So to make cooking more efficient, calcium carbonate would need to be added to soft water. Limiting the range of compounds tested to polystyrene, polyethylene and polypropylene is also indicated as problematic. Meanwhile, other plastic polymers, such as dangerous vinyl chloride, are also detected in tap and bottled water. It remains to be seen whether cooking will be effective in this case as well.
How can microplastics in tap water harm health?
The study published on January 8 this year. by a team of researchers at the University of California shows that a bottle of store-bought water may contain as many as 0.25 million micro- and nanoplastic particles. In terms of quantity, polyethylene terephthalate (PET), nylon, polystyrene and polyvinyl chloride (PVC) were identified the most. As you can see, there is not 100 percent overlap. with the types of microplastics detected by scientists in China. A growing number of studies indicate that microplastics in tap water, food and inhaled air can have catastrophic health effects. These are due to its prevalence and proven toxic effects. And traces of it have already been found in human blood.
Large microplastic particles penetrate body cells and cause oxidative stress in them. The more irregular their shapes, the more damage they do. We already know that they can damage DNA and disrupt liver and intestinal function, causing serious imbalances in internal microflora. Their accumulation leads to the development of adverse immune reactions and brain disorders. Studies in mice show that microplastics penetrate the blood-brain barrier and cause severe impairment of memory and learning processes.
In addition, it appears to have a negative impact on reproductive function, reducing fertility in individuals of both sexes. Polystyrene alone breaks down into styrene, which is considered a carcinogenic compound. Unfortunately, microplastics in tap water and food are not only toxic in themselves, but often contain other problematic compounds, especially heavy metals, phthalates, BPA, PFAS, harmful to the cardiovascular, endocrine and reproductive systems.
We will only know the full extent of the devastating effects of microplastics on human and animal health in the years to come, as the problem grows and more studies are conducted. For today, however, the option of reducing the amount of polymers consumed by boiling tap water seems very attractive, especially in locations with naturally hard water. For children and adolescents, who still have their whole lives ahead of them, this way of reducing potential risks could prove crucial.
For an opinion on the results of the Chinese study described above, we asked Dr. Ing. Edyta Łaskawiec, an employee of the Department of Environmental Biotechnology at the Silesian University of Technology.
Scientific studies show that in 1 liter of tap water there may be several to as many as a dozen microplastic particles. However, whether we will realistically be exposed to consuming tap water with such additives depends on a number of factors. First of all, from the source with which the water supply network is fed. Surface waters, including rivers and reservoirs, are more heavily exposed to various anthropogenic pollutants. Thus, the risk of microplastic particles will be much higher in them than in groundwater, which is naturally separated from many contaminants.
While it would seem that porous bed filtration processes are powerless to confront the new threat, analyses show that several to several percent of microplastic is removed from water already at the treatment stage. Consumers are often worried about the so-called “”new” technology. secondary contamination of tap water, which can be caused by the presence of plastic materials in networks and installations. However, for cold water transported in a temperature-stable and darkened environment, the risk of particle release is low.
The latest research on the effect of water hardness on the disposal of problematic pollution may prove relevant to our resources, which are characterized by elevated hardness. We often complain about limescale and sediment forming in kettles, but they can accumulate some of the impurities in themselves, improving the quality of the tap water. Undoubtedly, this is an interesting new aspect and another argument for using tap water to its full potential and without health concerns.
