Boiling Water to Reduce Microplastics in Drinking Water?

In an interesting study published on February 28 in Environmental Science & Technology Letters, researchers from China discovered a simple yet potentially effective method to significantly reduce the presence of nano- and microplastics (NMPs) in drinking water. By boiling mineral-rich water for just five minutes, individuals can decrease their exposure to NMPs by up to 90%. This finding is particularly crucial as scientists are only beginning to unravel the health risks associated with microplastic exposure, which includes potential oxidative stress, inflammation, insulin resistance, and liver issues.

NMPs, tiny plastic particles as small as one-thousandth of a millimeter in diameter, have been detected in various products and tap water. The study's method involves boiling water, which, when rich in minerals like calcium, leads to the formation of a chalk-like residue known as limescale or calcium carbonate (CaCO3). According to the study, this residue can trap microplastics, which are then removed by filtering the water through a standard coffee filter.

The effectiveness of this method is particularly pronounced in harder water, where the formation of more mineral solids results in the trapping of more microplastics. Dr. Anja Brandon, PhD, Associate Director of U.S. Plastics Policy at Ocean Conservancy and an environmental engineer not involved in the study, highlighted the importance of water hardness in the effectiveness of this microplastic removal method.

Microplastics are found in tap water primarily due to wastewater and surface runoff, posing a challenge for traditional water treatment plants that are unable to eliminate NMPs from drinking water. While advanced water filtration systems can capture and remove some tiny plastic bits, such technologies are not available in developing or underdeveloped countries, making the boiling method a viable and accessible solution for many.

In a summary article published in Healthline, I emphasized the cultural significance of boiling water before drinking as an old practice that can help reduce environmental exposures to infectious agents in the developing world. I also provided practical advice for those looking to implement this method, recommending boiling water in a glass pot, allowing it to cool without stirring, and then filtering or carefully pouring out the water into a glass jar while living untouched the chalky bottom residue, which would presumably contain the precipitated microplastics that settle at the bottom. 

I want to emphasize that this is only a partial solution to the issue of microplastics in the environment.  This once again puts the burden of reducing exposure onto individuals and does nothing for the continued extreme contamination caused by the exorbitant production, use, and waste of plastics into the environment caused by corporations. 

To summarize, boiling and filtering tap water presents a simple and potentially effective way to dramatically lower the amount of microplastics consumed by individuals whose tap water has high level of minerals. As research continues to shed light on the health risks associated with microplastic exposure, this study offers a practical solution for individuals seeking to reduce their exposure and protect their health.  However, it does nothing to address the uncontrolled production and release of microplastics into the environment, which produces exposure through other media such as in the food supply and the air. More needs to be done at the policy level to reduce plastics in the environment and promote remediation.

---