Researchers from Assam University have found a high concentration of lead and cadmium in water that leached from both old and new glazed, colourful ceramic cups heated in the microwave
Your brightly coloured tea cup/coffee mug could be leaching lead and cadmium into warm beverages.
According to a report by theÂ Hindustan Times, researchers from Assam University, Silchar, have found a high concentration of lead and cadmium -- the most common metals used in ceramics and glazed pottery -- in double distilled water that leached from both old and new glazed, colourful ceramic cups heated in the microwave (convection mode) at 140 degree Celsius for two-and-a-half minutes.
The report, titled â€˜Leachable lead and cadmium in microwave-heated ceramic cups: possible health hazard to humanâ€™, was published in Environmental Science and Pollution Research in November 2018.
It assumes importance given the widespread use of glazed colourful ceramic cups and mugs as well as microwaves in homes and workspaces to heat food and beverages.
These highly toxic and carcinogenic metals breached the US Food and Drug Administrationâ€™s (USFDA) permissible limits of 0.5 milligrams per litre (mg/l), according to the report.
As per the study, average concentration of lead was 15 times and six times higher in new cups (7.69 mg/l) and old cups (3.15 mg/l) than USFDA norms, respectively. Similarly, average cadmium concentration stood at 1.57 mg/l and 1.97 mg/l, respectively, which is four and three times higher than permissible limits.
India is yet to prescribe permissible standards. The Bureau of Indian Standards specifies limits for both these metals but only in enamelware. However, these are only voluntary and do not cover ceramics.
The research findings also apply to beverages prepared using a gas stove as the temperature of boiling water is enough to leach the metal from the cup wall.
Researchers warn that regular consumption of beverages from popular â€˜Made in Chinaâ€™ cups can be extremely harmful for children, pregnant women, or women of child bearing age, the report stated.