A study has shown that drinking tea can naturally absorb heavy metals such as lead and cadmium with water. Researchers at Northwestern University found that there are health benefits while drinking tea, it also gives an additional perk of purifying the water through the process of making alcohol.

Published in the Peer-review Journal ACS Food Science and Technology, the study defined “absorbed”, which “absorbs” as the ability of a solid material to keep gas, liquid molecules or disturbs substances on its outer surface or as a thin film inside the surfaces like Krevis.

Researchers found how the absorption of heavy metals depends on a variety of tea (black, green, oolong, white, chamomile and ruibos), especially if they were available or a larynx or bag made of cotton, nylon or cellulose (a natural biodegradable material made of wooden gup).

The team solved the concentrations of water and lead and other heavy metals such as cadmium, chromium, copper and zinc and then heated them just below the boiling point. Tea leaves or bags were then added to a warm solution and designed to stand.

The authors then studied the duration of different times from second to 24 hours in different time periods, before measuring how much of the metals remain in the water.

In the experiment, cellulose bags performed best, while cotton and nylon bags barely absorbed any metal.

“Nylon tea bags are already problematic because they release microplastic, but most of the tea bags used today are made of natural materials, such as Cellulose,” Dr. Benjamin Shindel said, the first study writer and contract engineer with the National Energy Technology Laboratory of the US Energy Department.

The type and piece of tea matters to some extent. For example, fine ground leaves were more effective in absorbing contaminants than whole leaves. “When tea leaves are processed in black tea, they open wrinkles and their holes are open,” Shindel said.

Drinking tea can usually filter about 15% lead from drinking water, the authors found. This estimate was proved by a mug of water and a tea bag was crushed for three to five minutes.

However, the length of time also matters. The longer they leave the tea, the more metals were adsorbed.

Since tea is one of the most consumed beverages in the world, the study provides an attractive insight on how this worldly activity can be beneficial in filtering water. However, not as an alternative to a proper filtering process.

“We are not suggesting that everyone starts using tea leaves as a water filter,” said Vinayak Dravid, senior writer of the study. “For this study, our goal was to measure the ability of heavy metals to absorb tea. By determining this effect, our work highlights the unfamiliar capacity for tea consumption to contribute to reduce the risk of heavy metal in population worldwide.”