The Occurrence of Disinfection By-Products (DBPs) of Health Concern in Drinking Water
Results of a Nationwide DBP Occurrence Study
More than 500 disinfection by-products (DBPs) have been reported in the literature for the major disinfectants currently used (chlorine, ozone, chlorine dioxide, chloramines), as well as their combinations (Richardson, 1998). Of these reported DBPs, only a small percentage have been quantified in drinking waters. Thus, there is significant uncertainty over the identity and levels of DBPs that people are actually exposed to in their drinking water. Moreover, only a limited number of DBPs have been studied for adverse health effects. To determine whether the other DBPs pose an adverse health risk, more comprehensive quantitative occurrence and toxicity data are needed. To address this issue, scientists at the U.S. Environmental Protection Agency's (USEPA's) National Exposure Research Laboratory (NERL) initiated a proposal for a Nationwide DBP Occurrence Study.
Drinking water treated with chloramines found to contain highly toxic chemicals, says EPA
Original source: http://www.newstarget.com/002902.html
. Genetic toxicologist Michael Plewa and Elizabeth Wagner, principal research specialist, both in the department of crop scieces, collaborated with three EPA researchers on research into a disinfection byproduct found in drinking water treated with chloramines.
. The discovery raises health-related questions regarding an Environmental Protection Agency plan to encourage all U.S. water-treatment facilities to adopt chlorine alternatives, said Michael J. Plewa [PLEV-uh], a genetic toxicologist in the department of crop sciences.
. "This research says that when you go to alternatives, you may be opening a Pandora's box of new DBPs, and these unregulated DBPs may be much more toxic, by orders of magnitude, than the regulated ones we are trying to avoid."
. Plewa and colleagues, three of them with the EPA, report on the structure and toxicity of five iodoacids found in chloramines-treated water in Corpus Christi, Texas, in this month's issue of the journal Environmental Science & Technology.
. "Not only do they represent a potential danger because of all the water consumed on a daily basis, water is recycled back into the environment.
. The use of chloramines, a combination of chlorine and ammonia, is one of three alternatives to chlorine disinfectant, which has been used for more than 100 years.
. Scientists believe they've identified maybe 50 percent of all DBPs that occur in chlorine-treated water, but only 17 percent of those occurring in chloramines-treated water, 28 percent in water treated with chlorine-dioxide, and just 8 percent in ozone-treated water.
. The DBPs in Corpus Christi's water were found as part of an EPA national occurrence survey of selected public water-treatment plants done in 2002.
USEPA Reports Scale and Film in Pipes Can Leach High Levels of Contaminants
U.S.Environmental Protection Agency (EPA) personnel reported disturbing drinking water distribution system revelations at the Inorganic Contaminants Workshop sponsored by the American Water Works Association on Feb. 1-3. Agency field engineers have been discovering that "regulated inorganic and radiological contaminants present in source water above detectable [analytical detection levels] but less than the safety standard, can accumulate in distribution systems to a significant number of times above their respective standard and that this is a largely unknown, unexplored and universal phenomena."
In other words, though the water leaving a municipal treatment plant complies with all EPA criteria, events occurring in the water distribution system after water leaves the plant can lead to significant spikes in contaminant levels.
Central Calif. Water District Ordered to Remove Chemical From Drinking Water
San Francisco, CA - The U.S. Environmental Protection Agency has ordered the Groveland Community Services District in Tuolomne County, Calif. to reduce levels of disinfection byproducts from the drinking water it provides to customers.
In this case, the byproduct chemicals are detectable in very trace amounts. The EPA does not suggest that customers need alternative or bottled water.
"Chemical byproducts in treated drinking water need to be monitored, reported and reduced to meet the federal health standard," said Marvin Young of the EPA's Drinking Water Office in the Pacific Southwest region. "In this case, the district notified the public and has begun changing their operations to prevent the byproduct from forming."
The Safe Drinking Water Act (SDWA)
The Safe Drinking Water Act (SDWA), as amended in 1996, requires EPA to establish criteria for a program to monitor unregulated contaminants and to identify no more than 30 contaminants to be monitored every five years. EPA identified and published unregulated contaminants for the previous UCMR cycle (i.e., UCMR 1), and a revised approach for monitoring, in the Federal Register dated September 17, 1999. UCMR 1 established a tiered monitoring approach, and required all large public water systems (PWSs) and a representative sample of small PWSs (serving 10,000 or fewer people) to monitor for unregulated contaminants from 2001-2005. (The original unregulated contaminant monitoring program (1988-1997) utilized State primacy and required PWSs serving greater than 500 people to monitor.)
Fact Sheet - Proposed Rule
Unregulated Contaminant Monitoring Regulation (UCMR 2) monitoring is proposed to occur during 2007-2010 and includes 26 unregulated contaminants and
nine associated analytical methods to be used in this monitoring cycle. The UCMR program was developed in coordination with the Contaminant Candidate List
(CCL). The CCL is a list of contaminants that are not regulated by national primary drinking water regulation, are known or anticipated to occur at public
water systems, and may warrant regulation under the Safe Drinking Water Act. The data collected through the UCMR program is being stored in the National
Contaminant Occurrence Database (NCOD) to support analysis and review of contaminant occurrence, to guide the CCL selection process, and to support the
Administrator's determination of whether to regulate a contaminant in the interest of protecting public health.
Data Sought for 26 Drinking Water Contaminants
Twenty-six unregulated contaminants will be monitored by many U.S. drinking water suppliers under a new rule proposed by the Environmental Protection Agency. This second cycle of the Unregulated Contaminant Monitoring Rule (UCMR 2) also proposes the use of nine analytical methods to detect the contaminants.
The data collected will help EPA determine whether to regulate the contaminants, their occurrence in drinking water, the potential population exposed to each, and the levels of exposure.
Byproduct of water-disinfection process found to be highly toxic
A recently discovered disinfection byproduct (DBP) found in U.S. drinking water treated with chloramines is the most toxic ever found, says a scientist at the University of Illinois at Urbana-Champaign who tested samples on mammalian cells.
The discovery raises health-related questions regarding an Environmental Protection Agency plan to encourage all U.S. water-treatment facilities to adopt chlorine alternatives, said Michael J. Plewa [PLEV-uh], a genetic toxicologist in the department of crop sciences.
USEPA characterizes many unregulated DBPs
USEPA researchers have quantified the occurrence of more than 200 previously unidentified disinfection by-products (DBPs) for the first time and determined that disinfectants other than chlorine can produce comparable levels of DBPs that may pose health risks, according to a new report from the agency's Ecosystems Research Division.
Toxins In Your Water
This is a warning you are used to hearing when you travel abroad, but now it's hitting home.
According to the Washington, D.C. based Environmental Working Group (EWG), manufacturers dumped more than one billion pounds of toxic chemicals into rivers, lakes and other bodies of water between 1990 and 1994. EWG also estimates that manufacturers contributed about 450 million additional pounds via sewage.
In the 1940's, a billion pounds of synthetic chemicals were produced each year. By the 1980's, production was up to 500 billion pounds, and 1000 new chemicals are introduced each year. Yet the Federal Safe Drinking Water Act only addresses 100 contaminants.