GLIN==> Disinfectants in water yield toxic results

Submitted by Debra Levey Larson <dlarson at illinois.edu>

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> Source: Michael J. Plewa (217-333-3614; mplewa at illinois.edu)
> Contact: Debra Levey Larson (217-244-2880; dlarson at illinois.edu)
>
> What's in your Water?: Disinfectants Create Toxic By-products
>
> URBANA - Although perhaps the greatest public health achievement of the 
> 20th century was the disinfection of water, a recent study now shows that 
> the chemicals used to purify the water we drink and use in swimming pools 
> react with organic material in the water yielding toxic consequences.
>
> University of Illinois geneticist Michael Plewa said that disinfection 
> by-products (DBPs) in water are the unintended consequence of water 
> purification. "The reason that you and I can go to a drinking fountain and 
> not be fearful of getting cholera is because we disinfect water in the 
> United States," he said. "But the process of disinfecting water with 
> chlorine and chloramines and other types of disinfectants generates a 
> class of compounds in the water that are called disinfection by-products. 
> The disinfectant reacts with the organic material in the water and 
> generates hundreds of different compounds. Some of these are toxic, some 
> can cause birth defects, some are genotoxic, which damage DNA, and some we 
> know are also carcinogenic."
>
> The 10-year study began with an EPA grant to develop mammalian cell lines 
> that would be used specifically to analyze the ability of these compounds 
> to kill cells, or cytotoxicity, and the ability of these emerging 
> disinfection by-products to cause genomic DNA damage.
>
> "Our lab has assembled the largest toxicological data base on these 
> emerging new DBPs. And from them we've made two fundamental discoveries 
> that hopefully will aid the U.S. EPA in their regulatory decisions. The 
> two discoveries are somewhat surprising," Plewa said.
>
> The first discovery involves iodine-containing DBPs. "You get iodine 
> primarily from sea water or underground aquifers that perhaps were 
> associated with an ancient sea bed at one time. If there is high bromine 
> and iodine in that water, when you disinfect these waters, you can 
> generate the chemical conditions necessary to produce DBPs that have 
> iodine atoms attached. And these are much more toxic and genotoxic than 
> the regulated DBPs that currently EPA uses," he said.
>
> Plewa said that the second discovery concerns nitrogen-containing DBPs. 
> "Disinfectant by-products that have a nitrogen atom incorporated into the 
> structure are far more toxic and genotoxic, and some even carcinogenic, 
> than those DBPs that don't have nitrogen. And there are no 
> nitrogen-containing DBPs that are currently regulated."
>
> In addition to drinking water DBPs, Plewa said that swimming pools and hot 
> tubs are DBP reactors. "You've got all of this organic material called 
> 'people' -- and people sweat and use sunscreen and wear cosmetics that 
> come off in the water. People may urinate in a public pool. Hair falls 
> into the water and then this water is chlorinated. But the water is 
> recycled again and again so the levels of DBPs can be ten-fold higher than 
> what you have in drinking water."
>
> Plewa said that studies were showing higher levels of bladder cancer and 
> asthma in people who do a lot of swimming - professional swimmers as well 
> as athletic swimmers. These individuals have greater and longer exposure 
> to toxic chemicals which are absorbed through the skin and inhaled.
>
> "The big concern that we have is babies in public pools because young 
> children and especially babies are much more susceptible to DNA damage in 
> agents because their bodies are growing and they're replicating DNA like 
> crazy," he said.
>
> Some public pools have been closed because they have high levels of 
> bacteria. "Public pools keep a high level of chlorine in the water to keep 
> bacteria and pathogens down but very little work research is conducted on 
> evaluating levels of generated dangerous disinfection by-products.
>
> "The idea is to keep the pools disinfected, keep them in compliance, just 
> as with drinking water but then use engineering techniques that reduce the 
> levels of these toxic by-products." Plewa described another project he is 
> working on as a researcher with a National Science Foundation Center 
> called WaterCAMPWS at the University of Illinois. "We're working with 
> engineers and chemists to develop new technologies that will disinfect 
> water, that will desalinate water, that will remove pharmaceuticals from 
> water but in so doing, don't generate by-products that are even more toxic 
> than the things you're trying to remove."
>
> Ironically, the DBPs that are regulated by the EPA tend to be some of the 
> least toxic DBPs in Plewa's study. "We've found that the emerging DBPs are 
> much more genotoxic and much more cytotoxic. But I can't fault EPA because 
> these data were not present at the time and in fact the development of the 
> database of over 70 DBPs has been done in concert with our colleagues at 
> the federal EPA."
>
> Plewa said that until new technologies are engineered to safely disinfect 
> the water in public pools, education is needed to encourage people to 
> bathe or shower before entering a public pool. "It's the organic material 
> that gets in the pool that is disinfected and then recirculated over and 
> over again. That's why we call swimming pools disinfectant by-product 
> reactors. But by public education, by personal behavior, there should be 
> ways that we can reduce the levels of the dissolved organic material that 
> should reduce the level of DBPs."
>
> Plewa, along with a team of scientists received a United States 
> Environmental Protection Agency Science and Technology award for their 
> paper Occurrence, genotoxicity and carcinogenicity of regulated and 
> emerging disinfection by-products in drinking water: A review and roadmap 
> for research. It was published in the scientific journal Mutation 
> Research.
>
> -30-