News Feature | December 10, 2015

Salt, Tap Water Combo May Cook Up Toxic Food

Sara Jerome

By Sara Jerome,

Recipes combining salt and tap water treated by chlorination or chloramination may create toxic food.

“When iodized table salt is added to tap water containing chloramines or chlorine during cooking, it reacts and creates hypoiodous acid. When this acid reacts to other organic matters in the tap water and food, it creates iodinated disinfection byproducts (I-DBPs). Some of these molecules have not been discovered yet and are completely new to engineers, toxicologists and environmental chemists,” Tech Times recently reported.

The findings are from researchers at Nanjing University in China and the Hong Kong University of Science and Technology. They conducted a study focused on cooking with chloraminated tap water and iodized table salt.

“In the study, the researchers tested the toxicity of the molecules by simulating the cooking process and adding iodized salt and wheat flour to the various types of tap water heated at various lengths and temperatures,” the report said.

“The team identified 14 new molecules, nine of which got toxicity level test, and found that several of them are 50 to 200 times more toxic compared to others. The presence of molecules during the simulated cooking ranged between 0.72 to 7.63 micrograms per liter,” the report said.

Xiangru Zhang, one of the researchers, explained the significance of the discovery.

"I-DBPs formed during cooking with chloraminated or chlorinated tap water are something new to environmental chemists, toxicologists and engineers," he said in a statement. "They are relevant not only to drinking water researchers and practitioners but also to the public."

Scientists have raised similar concerns about reactions between tap water and tea or coffee.

“Tea, and to a lesser extent coffee, contain organic aromatic compounds that give the drink its flavour, but these are also the compounds that react to form byproducts,” Chemistry World recently reported.

Tom Bond of Imperial College in London recently studied these reactions in tea and coffee.

“There is much debate and uncertainty in the scientific community about how hazardous disinfection byproducts really are. I don’t think there is anything to be worried about from disinfection byproducts in tea and coffee. There are many other studies focusing on the health benefits of tea in particular, which result from its antioxidant properties, and shouldn’t be forgotten,” he said, per the report.

For more on drinking water disinfection and DBPs, visit Water Online’s Disinfection Solutions Center.