In the News…
Public Health and Drinking Water News Briefs
May 28, 2004
With Chlorine as Disinfectant, Lead in D.C. Water Declines
Lead levels in Washington, D.C.’s recently maligned drinking water system dropped 25 to 30 percent after the D.C. Water and Sewer authority (WASA) switched from chloramines to chlorine for the District’s annual spring pipe flushing. The reported decline in lead levels in DC drinking water was sharper than expected, according to District officials. However they did caution that further studies are needed to determine whether in fact chlorine could stem the problem of lead in the water and what other factors may affect corrosion.
For several months, experts have questioned if the District’s lead problem was linked to a change in disinfectants in 2000 from chlorine to chloramines, a mixture of chlorine and ammonia. In 2002, household tests first revealed that lead levels exceeded federal limits.
Of the 1,683 D.C. homes with lead service lines tested in March 2004, 52 percent had excessive lead levels. In another testing sample – 478 homes with lead service lines – twenty six percent tested high from April 20th to May 8th, when the effect of the newly introduced chlorine would have been strongest.
To view the summary results of WASA’s Spring Flushing program please go to:
EPA Develops “Source Waters” Criteria for Cryptosporidium
The U.S. Environmental Protection Agency (EPA) has begun preliminary efforts to establish criteria in “source waters” for regulating Cryptosporidium, a pathogen found in both human and animal waste. No regulations are currently in effect regarding the amount of Cryptosporidium that is permitted in “source waters” from which utilities draw their drinking water supplies. The EPA has identified establishing such criteria as one of its top ten “highest priority” actions, according to an August 2003 plan developed by the EPA Office of Science and Technology, part of the agency’s Water Office.
The plan, Strategy for Water Quality Standards and Criteria, lists pathogens as the second most frequent cause of water quality impairments under the Clean Water Act, and cites the development of criteria on Cryptosporidium as a critical component of the agency’s three-prong “Strategy for Waterborne Microbial Disease Control.”
EPA hopes to complete development of Cryptosporidium criteria by the end of 2005. Once the criteria are in place, states will use them to establish water quality standards that may include enforceable discharge limits for both the wastewater treatment and agriculture industries.
West Nile Virus Looms as Summer Nears
With the official start of summer less than one month away, infectious disease experts with the U.S. Centers for Disease Control and Prevention (CDC) are warning of another challenging year for transmission of the West Nile virus. Last year, the number of reported human cases of West Nile virus in the United States was 9,800 – more than double the 4,156 recorded in 2002.
Experts have suggested that U.S. west coast states, specifically California, may be particularly vulnerable to the virus this summer. The combination of standing water in the Golden State’s urban areas and the heavy use of irrigation in agricultural areas foster prime breeding conditions for different types of West Nile carrying mosquitoes, CDC officials said.
First identified in the West Nile region of Uganda in 1937, the virus spread to the U.S. in 1999. Primarily transmitted by mosquitoes, the virus can infect humans, animals and birds. Although most infected people do not show any signs of illness, up to 20 percent can experience flu-like symptoms like fever, headache, and body aches.
To read further information from the CDC on the West Nile Virus, please go to:
EPA Establishes DRINK System
The U.S. Environmental Protection Agency (EPA) has developed a publicly accessible, web-based network to provide the latest information on drinking water research. The Drinking Water Research Information Network (DRINK) tracks ongoing research conducted by the EPA and partners from national, regional and international research agencies and organizations.
DRINK contains descriptive information on research projects, including title, abstract, start and end dates, principal investigator and contact information. Users can obtain information on research topics of individual interest and minimize the duplication of research by different organizations.
The creation of DRINK was initiated after the release of an October 1999 U.S. General Accounting Office (GAO) report recommending that the EPA better communicate the efforts of the drinking water research community. With the launch of DRINK the EPA improves its capacity to identify research priorities by determining what researchers are planning to study in the future and the status of their current efforts.
For further information about the EPA’s DRINK program, please go to:
In The News-is a bi-weekly, online service from the Water Quality & Health Council. The publication is updated every other Friday and can be viewed by logging onto www.waterandhealth.org. To receive the publication via e-mail, please click here and enter your e-mail address to join our mailing list.