Monday, May 9, 2016

Cooking foods with chlorinated water and iodized salt-potential generation of toxic artifacts

Scientific research some times brings out unexpected observations which can scare ordinary people besides causing anxiety regarding the safety of foods we eat to day. It is difficult to imagine that the world has travelled during the last hundred years with the boundaries of science stretched every day bringing in new knowledge, good as well as bad. The problem with the layman is to discern what is truth and what is biased or motivated research. Recent revelation by the famous food guru Prof Marion Nestle that food research is losing its credibility because of prolific funding of many studies by the industry which wants results suiting its corporate goals rather that getting true facts is really startling. The reported findings by a group of scientists that cooking the food with commonly available salt and water tapped from the public supply in most towns and cities can pose danger to the health of the consumer is both alarming and scary. What is the science behind this latest bombshell?

"May be these scientists from Hongkong and Beijing Universities have a point in publishing these results based on their simulated studies but how it is going to relate to the day to day lives of people is a million dollar question, Some of the basic surmises used in these studies are that use of chlorinated water in cooking is a universal practice, use of salt during cooking is common and iodized salt contains potassium iodide. Of course in many cases these assumptions may be true and therefore dissemination of the results could be for common good. It is true that chlorine is to day widely used for water disinfection in many countries though many others have discontinued this practice some years ago. Our tap water is disinfected before we drink it or use it in cooking. This is done in several ways, including by adding chlorine or molecules called chloramines that are made using ammonia. These two processes - chlorination and chloramination - have an effect on the chemical make-up of the water. Chlorine or chloramines in your tap water can react with the iodized table salt you add to your food, creating a kind of acid called hypoiodous acid. This in itself isn't cause for concern, but the acid can then react with the food and other organic matter in the tap water to create cooking iodinated disinfection byproducts (I-DBPs) - molecules that are almost completely new to researchers. For the new study, the team identified some molecules and tested their toxicity. "I-DBPs formed during cooking with chlorinated 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." The researchers analysed the I-DBPs formed during cooking with chlorinated and chloraminated tap water. They simulated cooking with different types of tap water at varying temperatures and time, and added wheat flour and iodized salt to see what I-DBPs would be formed. Using cutting-edge chemistry techniques, they identified 14 completely new molecules and determined the structure of nine molecules. They then carried out tests to see how toxic nine of the molecules are and found that some of the molecules are 50-200 times more toxic than others. "Considering that these molecules could have an adverse effect on our health, we need to study them more to determine exactly what effects they might have," said Dr. Yang Pan, one of the study's authors and Assistant Professor at Nanjing University. "We have therefore proposed some practical suggestions to limit their formation during cooking." The cooking conditions, such as the type of water and salt used, the cooking temperature and time, had an effect on the formation of I-DBPs. In the study, molecules were present in the simulated cooking water at varying concentrations, from 0.72 to 7.63 micrograms per liter. Adjusting the cooking conditions can minimize the concentrations of I-DBPs in the water.Dr. Zhang and the team suggest that people use chlorinated rather than chloraminated tap water, and use table salt fortified with potassium iodate instead of potassium iodide. Cooking at lower temperatures, for less time, also limits the formation of I-DBPs. "

The above findings do raise some concerns though optimists may always take them easy as nothing untowards have happened so far to the humanity though chlorination was a globally accepted practice for more than a century. But this may be too simplistic because millions of people who die every year meet their end due to hundreds of reasons, some well identified while others due to unknown reasons. The artifacts created by chlorination might not be dangerous alone but in combination with other factors can turn out to be unsafe in the long term. After all iodization of salt is a relatively new development and manifestation of its ill effects may surface after a few years. The suggestion that salt should be iodized with iodate in stead of elemental iodine seems to an eminent one so that till firm conclusions are drawn about I-DBPs iodine is not used for iodization of salt. With vast knowledge emerging about nano particles and their impact on human body, even traces of injurious chemicals can create havoc with human body. It is better to be cautious avoiding even a remote chance of risks with such compounds in our foods. 


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