According to a recent study carried out at the Hong Kong University of Science and Technology and Nanjing University in China, and published in Water Research, cooking with tap water, which contains chlorine by-products, and adding iodised salt to the water could produce harmful toxins that end up in your food.
The tap water in most countries is disinfected for use, and in most countries, this is done by adding chlorine or chloramines that are made using ammonia. These two processes, called chlorination and chloramination, both affect the chemical make-up of the water.
When you add iodised salt to your food while cooking it in tap water, it could create a kind of acid called hypoiodous acid which could react with the food and other organic matter in the water and create cooking iodinated disinfection by-products (I-DBPs).
“I-DBPs formed during cooking with chloraminated or chlorinated tap water are something new to environmental chemists, toxicologists and engineers,” said Dr Xiangru Zhang, corresponding author of the paper and Associate Professor at the Hong Kong University of Science and Technology. “They are relevant not only to drinking water researchers and practitioners but also to the public.”
Researchers identified 14 completely new molecules and determined the structure of nine molecules, after which they carried out tests that determined that some of the molecules are 50-200 times more toxic than others.
While research authors say that further studies are required to find out more about these molecules and their effect, if any, on our health, they have suggested that we should rather limit the temperature at which we cook and the cooking time and rather use salt that is fortified with iodate instead of iodide.
In the meantime though, it might be a good idea to get a mains water cooler with a filter so that you do not only have pure, toxin-free drinking water but also have a better source of water you can use for food preparation. The top of the range models at Living-Water offer cold, ambient and hot water options so you need not worry about having to cook with ice-cold water.
