A new review by the World Health Organisation (WHO) has found that the potential health risks from consuming microplastics in our drinking water are not yet known.
Microplastics are “ubiquitous” in the food we eat and in drinking water, both bottled and tap, the report said. Australian research revealed in June that, on average, we could ingest about five grams of plastic every week which is the equivalent weight of a credit card. However, the health impact is unclear and requires further research.
“We urgently need to know more about the health impact of microplastics because they are everywhere – including in our drinking-water,” says Dr Maria Neira, director of the Department of Public Health, Environment and Social Determinants of Health at WHO.
“Based on the limited information we have, microplastics in drinking water don’t appear to pose a health risk at current levels. But we need to find out more. We also need to stop the rise in plastic pollution worldwide.”
Associate Professor Duncan McGillivray from the School of Chemical Sciences at the University of Auckland said we are more exposed to microplastics than we think.
“There are studies that have shown the presence of as much as 1000 particles per litre of bottled water,” McGillivray said, adding that we shouldn’t “panic” about microplastic but we “should not relax” either: “There are too many unknowns about how microplastics impact health.”
Concerns about the possible effects of ingesting microplastics include that they could damage the immune system, cause inflammation, or carry toxins such as mercury or pesticides. In sea mammals, plastics are thought to damage fertility.
Until there is greater understanding about the health effects, some experts suggest drinking filtered water to help remove microplastics along with the pharmaceuticals and illicit drugs that have also been found in drinking water supplies around the world.
“Opting for filters would aid in the removal of the microplastics. It would also aid in the removal of other pollutants like heavy metals and pathogens,” said Dr Paul Harvey, an environmental scientist and environmental chemist at Macquarie University.
Thava Palanisami, a senior research fellow at the University of Newcastle’s Global Centre for Environmental Remediation, agrees.
“Microplastics in drinking water is increasingly abundant, but it is geographic dependent as well,” said Palanisami. Studies have not yet looked exclusively at the levels in Australia.
“At present, there is sufficient evidence to understand the human health impact of plastic-related chemicals (BPA, phthalates) but not for microplastics yet.
“Filtration is one of the simple options that can be applied, it will reduce the exposure to all the particle pollutants in water to a certain level.”
Not all filters are the same quality or as efficient as each other (though Choice provides a guide) and, of course, they are only part of the solution.
“Using filters is a good strategy for ‘cleaning up’ the problem, but a far more effective approach is to remove the sources of pollution before they reach the drinking water,” Dr Harvey said.
“In Australia, we have a lot of complacency about drinking water pollution because we are told by regulators that there is no problem and there is very little solid research to back up anecdotal concerns raised by the community.”