A recent study has unveiled a surprising benefit of brewing tea: its potential to remove toxic heavy metals, such as lead, from drinking water. Published on February 24 in the journal ACS Food and Science Technology, the research explored the capacity of various teas to act as natural purifiers. Conducted by a team of scientists who purchased different types of teas, including black, green, chamomile, oolong, white peony, and rooibos, the study found that a typical cup of tea could eliminate approximately 15% of lead from water with concentrations up to 10 parts per million.
The study utilized a brewing time of three to five minutes for its experiments. Benjamin Shindel, a materials scientist at Northwestern University and the study's first author, highlighted the enhanced efficacy of longer brewing times, suggesting that overnight steeping could recover most metals present in the water.
"Any tea that steeps for longer or has higher surface area will effectively remediate more heavy metals." – Benjamin Shindel, a materials scientist at Northwestern University.
The Environmental Protection Agency (EPA) sets the actionable limit for lead in public drinking water at 15 parts per billion. However, there is no safe level for lead consumption. This makes the study's findings significant, as they suggest tea could serve as an auxiliary method for reducing lead content in water, particularly in areas with inadequate water systems.
Vinayak Dravid, a professor of materials science at Northwestern University, emphasized the importance of this discovery.
"Our goal was to measure tea's ability to adsorb heavy metals. By quantifying this effect, our work highlights the unrecognized potential for tea consumption to passively contribute to reduced heavy metal exposure in populations worldwide." – Vinayak Dravid, a professor of materials science at Northwestern University.
While promising, researchers caution that tea should not replace proper water filtration systems. The study's results are based on controlled experiments using a single teabag and one mug of water. The researchers suggest that increasing the brewing duration can further enhance tea's ability to remove metals from water.
The global consumption of tea surpasses 5 billion cups daily, making it the second most consumed beverage after water. This widespread consumption could potentially contribute to public health improvements if leveraged correctly.
"Across a population, if people drink an extra cup of tea per day, maybe over time we'd see declines in illnesses that are closely correlated with exposure to heavy metals." – Benjamin Shindel.
While the study underscores the potential benefits of tea as a natural purifier, the researchers stress that it should not be solely relied upon for ensuring clean drinking water. Instead, it may serve as a complementary approach in conjunction with established filtration technologies, providing additional assurance against heavy metal exposure.
