The world's most popular beverage may do more than just warm you up or wake you up — it could help protect you from lead contamination. New research reveals that the simple act of steeping tea removes a meaningful portion of lead from drinking water, with the tea leaves acting as a natural filter.
Scientists found that brewing black tea under typical conditions can filter out approximately 15% of lead from contaminated water. The study, published in Environmental Science & Technology Letters, shows that the same properties that make tea leaves excellent for brewing — high surface area and quick release of compounds in hot water — also make them surprisingly effective at trapping heavy metals.
"We're not recommending tea leaves as a water filter," the researchers wrote. "Rather, we're quantifying an unrecognized benefit that may already be helping populations worldwide." This passive filtration could be significant in regions that both consume lots of tea and face challenges with lead contamination.
The research team tested multiple varieties of tea, from black and green to oolong and white, finding that most performed similarly well at lead removal. The exception was chamomile, which proved less effective due to its different plant structure. They also discovered that finely ground tea leaves worked better than whole leaves, and that cellulose tea bags contributed additional filtering capacity while plastic mesh bags did not.
Temperature played a key role — hot water accelerated the process compared to room temperature brewing, though stirred room-temperature tea eventually reached similar levels of lead removal. The researchers found the effect remained stable across typical drinking water pH levels from 4 to 10.
The study authors conclude: "While not a complete solution to lead contamination, in the absence of dedicated water treatment infrastructure, this passive remediation offered by tea preparation provides a readily available and culturally integrated means of reducing lead exposure, potentially contributing to improved public health outcomes."
Previously:
• Ireland and England's 'best' teas, reviewed by an American
• Barry's Gold Blend is my favorite tea, PG Tips leaves me mildly depressed
• Teavana Tea cheats you twice
• 34-ounce glass tea press for loose teas and tea bags
• Barry's Irish Breakfast is a light version of my favorite tea
