According to recent research, coffee can remove from tap water from 78 to 90 percent of the contained heavy metals such as lead and copper, because an unsecured or negatively charged particles of coffee grounds attract positively charged particles of heavy metals. “The stronger the coffee, the more effective the removal of heavy metals,” says the chemist, specialist in environmental protection, Dr. Mike McLaughlin. The same experiments were conducted with tea bags. Tea removes water from about a third of the lead, but, it seems, almost does not reduce copper content.