They say that if you boil and filter your water, you can remove 90% of the plastic.
Maybe curtailing plastics didn't occur to them
By AMERICAN CHEMICAL SOCIETY
Nano- and microplastics are seemingly everywhere — water, soil, and the air. While many creative strategies have been attempted to get rid of these plastic bits, one unexpectedly effective solution for cleaning up drinking water, specifically, might be as simple as brewing a cup of tea or coffee.
As reported in ACS’ Environmental Science & Technology Letters, boiling
and filtering calcium-containing tap water could help remove nearly 90% of the
nano- and microplastics present.
Contamination of water supplies with nano-
and microplastics (NMPs), which can be as small as one-thousandth of a
millimeter in diameter or as large as 5 millimeters, has become increasingly
common. The effects of these particles on human health are still under
investigation, though current studies suggest that ingesting them could affect
the gut microbiome.
Some advanced drinking water filtration
systems capture NMPs, but simple, inexpensive methods are needed to
substantially help reduce human plastic consumption. So, Zhanjun Li, Eddy Zeng,
and colleagues wanted to see whether boiling could be an effective method to
help remove NMPs from both hard and soft tap water.
Research Findings on Boiling Water to Remove Plastics
The researchers collected samples of hard tap
water from Guangzhou, China, and spiked them with different amounts of NMPs.
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 (CaCO3). Results from these experiments indicated that as
the water temperature increased, CaCO3 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 NMPs. He suggests any remaining incrustants floating in the
water could be removed by pouring it through a simple filter such as a coffee
filter.
Efficacy in Different Water Types
In the tests, the encapsulation effect was
more pronounced in harder water — in a sample containing 300 milligrams of CaCO3 per liter of water, up to 90% of free-floating
MNPs were removed after boiling.
However, even in soft water samples (less
than 60 milligrams CaCO3 per liter),
boiling still removed around 25% of NMPs. The researchers say that this work
could provide a simple, yet effective, method to reduce NMP consumption.
Reference: “Drinking Boiled Tap Water Reduces
Human Intake of Nanoplastics and Microplastics” by Zimin Yu, Jia-Jia Wang,
Liang-Ying Liu, Zhanjun Li and Eddy Y. Zeng, 28 February 2024, Environmental Science & Technology Letters.
DOI:
10.1021/acs.estlett.4c00081
The authors acknowledge funding from the
National Natural Science Foundation of China.