Melamine involved in further health concerns

Serving hot food in melamine bowls can cause melamine to leach into the food, say Taiwanese researchers.

Researchers compared the melamine levels in the urine of people who had eaten hot noodles from either melamine or ceramic bowls. They found that those eating from melamine excreted higher levels of melamine in their urine than those eating from ceramic bowls.

While the authors of the study caution that melamine tableware may release the chemical when used with hot food, they did not comment on the effect this may have on the body. They also noted that the amount of melamine released varies by brand, so the result of this study, which focused on just one brand, may not be generalised to other brands.

“Melamine is familiar to us as the base chemical which makes the robust melamine plastic tableware,” said Dr Ian Musgrave, a Senior Lecturer in the University of Adelaide’s Faculty of Medicine.

“Melamine is also infamous as an illegal adulterant in pet food and children’s milk formulas. The levels of melamine that caused these problems were enormously higher than what we are likely to consume from our normal diet. However, long-term consumption of lower levels of melamine may be associated with an increased risk of kidney stones.

“The paper by Wu et al provides a possible route of melamine exposure. Very hot foods in melamine plastic tableware can cause melamine to leach into the food. Wu et al show that hot (90°C) soup will leach melamine from melamine plastic soup bowls and this is absorbed by the body and excreted in the urine.

“They showed that the melamine is very rapidly excreted and that the total levels excreted suggest an exposure to melamine over 600 times lower than the most stringent exposure limit. This is despite the researchers using a brand of melamine ware with the highest melamine leaching on contact with hot fluids.”

Dr Musgrave says it is likely the risk from standard household use is less than this study indicates, given that few households are likely to serve soup near boiling point in melamine bowls.

“However, the fact that even small amounts of melamine can leach from these ubiquitous food containers at high temperatures should make us cautious,” Dr Musgrave said. “It may be useful to test melamine tableware for melamine leaching and only permit the sale of low leachant tableware. It may also be prudent to avoid keeping very hot foods in melamine bowls for extended periods of time.”

‘A Crossover Study of Noodle Soup Consumption in Melamine Bowls and Total Melamine Excretion in Urine’, by Chia-Fang Wu et al, was published online in JAMA Internal Medicine on 21 January.