There is an simple way to strip toxic chemicals out of tap water using two common household items, according to a new study.
Researchers from Jinan University in China have discovered that boiling water then filtering it with a coffee filter removed almost 90 percent of tiny plastics that are linked to cancer and reproductive disorders.
These microplastics are so ubiquitous they were found in 129 of 159 tap water samples from 14 countries worldwide in the study.
Boiling water was particularly effective when used on ‘hard’ water, or water with large concentrations of minerals like calcium and magnesium.
At high temperatures, limescale will become solid, effectively ‘encrusting’ the plastics particles, and making them easy to remove through a filter.
Boiling water can trap nano- and microplastic inside limescale particles, which can then be easily filtered out
Over time, microplastics break down into nanoplastics, which are so small they can pass through our intestines and lungs into the blood, moving through the body to organs like the heart and brain
The plastic particles carry phthalates – a group of chemicals used to make plastics more durable and flexible and last longer – which are known to interfere with hormone production in the body, which may raise the risk of reproductive disorders and cancers.
Phthalates are ‘linked with developmental, reproductive, brain, immune, and other problems’, according to the National Institute of Environmental Health Sciences.
Nano- and microplastics also carry toxins on their surface such as heavy metals.
Over time, microplastics break down into nanoplastics, which are so small they can pass through our intestines and lungs into the blood, moving through the body to organs like the heart and brain.
Some advanced drinking water filtration systems capture nano- and microplastics, but simple, inexpensive methods are needed to substantially help reduce human plastic consumption.
Reports indicate plastic chemicals are linked to $249 billion in US healthcare costs in just one year.
The map compiled by the US Geological Survey shows the number of PFAS or ‘forever chemicals’ detections across a sprawling number of sites nationwide between 2016 and 2021
The researchers wanted to see whether boiling could be an effective method to help remove the plastics from both hard and soft tap water.
Hard and soft water are different in the minerals they contain.
More particles were able to be removed from hard water than from soft water, because the microplastics get trapped inside the limescale particles, and hard water has more of these.
Soft water doesn’t have high calcium and magnesium levels, but usually has higher salt concentrations unless it’s been softened with a potassium-based filtration system.
Approximately 85 percent of US water is classified as hard, but many homes and businesses utilize water softeners to strip minerals, making the water soft.
The researchers collected samples of tap water from Guangzhou, China, and spiked them with different amounts of nano- and microplastics.
They found an average concentration of one milligram per liter of nano- and microplastics.
Samples were boiled for five minutes and allowed to cool. Then, the team measured the free-floating plastic content.
Boiling hard water, which is rich in minerals, will naturally form a chalky substance known as limescale, or calcium carbonate.
‘We estimated that intakes of nano- and microplastics through boiled water consumption were two to five times less than those through tap water on a daily basis,’ said Zeng.
Results from these experiments indicated that as the water temperature increased, the limescale formed incrustants, or crystalline structures, which encapsulated the plastic particles.
Zeng says that over time, these incrustants would build up like typical limescale, at which point they could be scrubbed away to remove the nano- and microplastics.
He suggests any remaining incrustants floating in the water could be removed by pouring it through a simple filter such as a coffee filter.
In the tests, the encapsulation effect was more pronounced in harder water — in a sample containing 300 milligrams of limescale per liter of water, up to 90 percent of free-floating nano- and microplastics were removed after boiling.
However, even in soft water samples (less than 60 milligrams limescale per liter), boiling still removed around 25 percent of nano- and microplastics.
The researchers say that this work could provide a simple, yet effective, method to reduce nano- and microplastic consumption.
The study was published in the journal ACS’ Environmental Science & Technology Letters.
Phthalate exposure is attributed to 100,000 premature deaths in the US each year.
