The World Health Organization (WHO) issued a new report titled "Microplastics in drinking-water" (124-page PDF) “Based on the limited information we have, microplastics in drinking water don’t appear to pose a health risk at current levels," said Dr. Maria Neira, Director, Department of Public Health, Environment and Social Determinants of Health, at WHO. "But we need to find out more. We also need to stop the rise in plastic pollution worldwide.”
From WHO's press release:
Further research is needed to obtain a more accurate assessment of exposure to microplastics and their potential impacts on human health. These include developing standard methods for measuring microplastic particles in water; more studies on the sources and occurrence of microplastics in fresh water; and the efficacy of different treatment processes.
WHO recommends drinking-water suppliers and regulators prioritize removing microbial pathogens and chemicals that are known risks to human health, such as those causing deadly diarrhoeal diseases. This has a double advantage: wastewater and drinking-water treatment systems that treat faecal content and chemicals are also effective in removing microplastics.
Wastewater treatment can remove more than 90% of microplastics from wastewater, with the highest removal coming from tertiary treatment such as filtration. Conventional drinking-water treatment can remove particles smaller than a micrometre. A significant proportion of the global population currently does not benefit from adequate water and sewage treatment. By addressing the problem of human exposure to faecally contaminated water, communities can simultaneously address the concern related to microplastics.