Millions of Indians inadvertently eat toxic and carcinogenic metals in the form of thin silver foil traditionally used to garnish sweets and betel leaf, study results say. The silver foil, easily available in Indian markets, contains residues of carcinogenic nickel, lead, chromium and cadmium, according to a study by the Industrial Toxicology Research Center (ITRC) in the northern city of Lucknow.
In an age-old tradition, a finely pounded sheet of silver, so thin it splits when touched, is placed atop many Indian sweets.
Silver film is sometimes also used to wrap betel leaf, which is stuffed with betel nut, lime and other condiments and is chewed as a digestive.
"There is a good chance of consuming toxic metals while eating sweets wrapped with silver foil," said Dr. Mukul Das, who carried out the study.
Eating tiny amounts of pure silver is not considered toxic to humans, but many vendors use foil adulterated with heavy metals, Das said.
"Over half of the analyzed silver foils had lower silver purity than the 99.9 per cent purity stipulated by the prevention of food adulteration act of India," he said.
When such foil enters into the body it releases heavy metals that can lead to cancer, said Dr. S.K. Khanna, the co-author of the report released last month.
The report advocates controls for making silver foil.
It details the unhygienic conditions in which workers put silver in small leather bags and beat it into foil with wooden clubs in dingy shops.
One such artisan, Mukhtar Ali, said no health official had ever visited his workshop in Lucknow.
"Can silver be impure? Silver is a pure element and has no side effect," he said. "Moreover, I have never heard anybody complaining about silver foil."
Food inspector Sidharth Mathur said that a law specifies the required purity of silver foil for eating, but authorities have no way to test the purity, the AP says.
"Our labs are not competent enough" to make such checks, he said.
Garnishing some foods with silver foil is so popular in India that ITRC scientists believe that about 275,000 kilograms (606,265 pounds) of pure silver is converted into edible silver foil each year in the country.