A unique research confirmed drinking water contains microplastics
The researchers from the Institute of Hydrodynamics confirmed the presence of plastic particles in drinking water from the three water treatment plants (WTPs) in the Czech Republic. Microplastisc were present in all analyzed samples of both raw and treated drinking water. The results of this unique research are being published in the prestige journal Science of the Total Environment.
Microplastics (MPs) are usually defined as particles smaller than 5 mm, while the lower limit is not clearly stated. They can get into the environment either as a part of the consumer products such as cosmetics or cleaners, or they are formed by disintegration of larger items, e.g. by release of synthetic fibres during washing of clothes or decomposition of plastic waste. Despite conventional waste water treatment plants have shown an ability to remove a part of microplastics, large amounts of MPs pass through the process, and can get into the drinking water sources.
The first research of it's kind
The existing studies did not deal sufficiently with the microplastics occurence in the water sources or in drinking water itself. The research of the scientists from the Institute of Hydrodynamics is unique, for it evaluates the presence of microplastic particles not only in water sources but also in the treated water. The raw and treated water samples were acquired from the three different water treatment plants in the Czech Republic. All of them are located in populated industrial regions, but they differs from each other in the type of water source and treatment technology. The number of particles, their size, shape and material composition were analyzed in raw and treated water.
Microplastics were detected in all samples
Microplastics were found in all water samples and their average abundance ranged from approximately 1500 to 3600 particles l-1 in raw water and from 340 to 630 particles l-1 in treated water, depending on the WTP. Thus, the decrease in the number of MPs after passing the treatment process was around 70-83%. The majority of the MPs comprised of commonly utilized plastic materials such as PET (polyethylene terephthalate, 27-68 %), PP (polypropylene, 16-26 %) and PE (polyethylene, 24 %). Further, MPs smaller than 10 µm were the most plentiful in both raw and treated water samples, accounting for up to 95%. The fraction of 1-5 µm dominated in all samples. The majority of published studies (evaluating the occurence of plastics in the water environment) have not dealt with the particles smaller than 5 µm. Therefore, it can be assumed that with respect to a gradual degradation of the larger plastic particles, a considerable portion of microplastics was not detected in these studies at all.
A need of special technology
Water treatment plants do not have special technologies for microplastics elimination currently. Although this study proved that existing treatment technologies can remove a significant part of microplastics, they deserve a further attention due to possible health risks (provided that MPs can potentially bind harmful substances).
Download the paper "Occurrence of microplastics in raw and treated drinking water" in Science of the Total Environment