Water disinfectants up Alzheimer's risk

Drinking water disinfection byproducts suggests a possible connection to adverse health effects, including neurological diseases such as Alzheimer's, a new study has warned. University of Illinois scientists report the first identification of a cellular mechanism linked to the toxicity of a major class of drinking water disinfection byproducts. "I'm not implying that drinking disinfected water will give you Alzheimer's," said Michael Plewa, lead scientist and professor of genetics in the U of I Department of Crop Sciences. "Certainly, the disinfection of drinking water was one of the most significant public health achievements of the 20th century. But the adverse effects of disinfection byproducts (DBPs) that are unintentionally formed during this process are causing concerns as researchers unveil their toxicity." More than 600 DBPs have been discovered. Although researchers know some DBPs are toxic, little biological information is available on the majority of these water contaminants. The Environmental Protection Agency regulates only 11 of these DBPs, he said. Plewa's laboratory investigated the biological mechanism, or the cellular target that leads to toxicity, in the second-most prevalent DBP class generated in disinfected water - haloacetic acids (HAAs). They discovered that the HAA disinfection byproducts were toxic because the cells cannot make ATP, and this causes oxidative stress. "Cells treated with HAAs experience DNA damage," Plewa said. "So they start expressing DNA repair systems. HAAs are not directly damaging DNA, rather they are inhibiting GAPDH, which is involved in increasing the oxidative stress that we are observing."