Tea Leaves Naturally Remove Heavy Metals from Water: Study

Why in the News?

A study published in ACS Food Science & Technology found that tea leaves adsorb heavy metals like lead and cadmium during brewing. This discovery highlights tea’s potential role in reducing heavy metal exposure, benefiting global public health.

Tea Leaves Naturally Remove Heavy Metals from Water: Study

How Tea Leaves Remove Heavy Metals?

  • A new study reveals that tea leaves can adsorb heavy metals like lead and cadmium from water.
  • Researchers found that metal ions stick to the surface of tea leaves during brewing, reducing contamination.
  • Various teas, tea bags, and brewing methods were tested using water solutions containing lead, chromium, copper, zinc, and cadmium.
  • Tea steeped for different durations (seconds to 24 hours) showed a significant reduction in metal levels.

Key Findings of the Study:

  • A typical cup of tea (one mug of water, one tea bag, steeped for 3–5 minutes) removes up to 15% of lead from water.
  • Longer steeping times (overnight) resulted in almost complete metal removal.
  • Cellulose tea bags were more effective in metal adsorption than cotton and nylon due to higher surface area.
  • Finely ground black tea leaves adsorbed more metals than whole leaves for the same reason.

Significance and Public Health Impact:

  • Tea is the most consumed beverage globally, meaning its natural filtration properties could impact public health.
  • The findings suggest a possible link between tea consumption and lower rates of heart disease and stroke.
  • While not a replacement for filtration systems, this research highlights tea’s potential role in reducing heavy metal exposure