Study Warns Adding Chlorine To Drinking Water May Produce Major Toxins

A new study out of Johns Hopkins University has found that ordinary drinking water in the US — the kind you get straight from the tap — may contain unintended and highly toxic compounds that result from the method used to disinfect water. The issue revolves around chlorine, which is the most popular method of disinfecting drinking water in the US; though this has helped save millions of lives from deadly water-borne diseases, it does come with an unanticipated consequence.

Water-borne diseases are, of course, things like typhoid and dysentery that can be contracted from drinking contaminated water. These diseases may be deadly, particularly in children and the elderly; dirty drinking water is responsible for tens of thousands of deaths every year. Chlorine is a popular method for treating drinking water as it effectively kills off pathogens.

According to a new study led by Johns Hopkins University and recently published in Environmental Sciences & Technology, using chlorine to treat drinking water also produces 'highly toxic byproducts' in the presence of chemical compounds called phenols. Because phenols are very common in things like medication and hygiene products, they're also very common in water.

Phenols and chlorine produce 'a large number of byproducts' when they mix, according to the new study. The researchers behind this project set out to identify these resulting compounds, a process that involved chlorinating water the same way that drinking water is treated and then adding a compound very similar to the lysine amino acid found in the human body. After letting the mixture incubate for a day, the team used mass spectrometry to analyze the chemicals.

This process led to the discovery of two BDA compounds in the water, both of which are described as 'very toxic' and known carcinogens. This was the first time BDA compounds were found in chlorinated water, raising questions over the impact this method has on human health and whether other methods like filtration would be more advisable.