In the News…
Public Health and Drinking Water News Briefs
August 11, 2006
EPA Releases Coliform Guide for Small Water Systems
The U.S. Environmental Protection Agency (EPA) has released a new handbook to help small non-community drinking water systems understand and comply with the federal Total Coliform Rule (TCR). Total Coliform Rule: A Handbook for Small Noncommunity Water Systems Serving Less Than 3,300 Persons, is aimed at small water systems that supply parks, rest areas, restaurants, hospitals, schools and day care centers that are not served by a public water utility.
The guide outlines sampling procedures and compliance measures to assist small water system operators in the identification of total coliform and the possibility of potential water quality issues.
The natural inhabitants of soil, lakes and rivers, total coliforms are a group of closely related bacteria that are generally harmless. However, their presence in drinking water can be an indicator of a potential water system breach or a change in the integrity of the system that may allow pathogens to enter into public drinking water. Additionally, detection of total coliforms can be a warning sign that the water system is vulnerable to hazardous fecal contamination caused by line breaks, cross-connections or compromised water sources, according to the EPA.
The EPA report features a simplified diagram (below) to assist understanding of the importance of total coliform detection.
The TCR sets maximum levels for certain biological contaminants in water systems and requires the periodic collection of water samples to detect the presence of coliform bacteria. Water systems exceeding theses levels must be tested further to determine if fecal coliforms or even E. coli are present. The number of routine samples required each month, quarter, or year depends on the water system’s size and source water.
To read the guide in full, please visit:
Waterborne Disease Research Summaries Published
The U.S. Environmental Protection Agency’s Office of Research and Development and Office of Water have re-issued a series of papers summarizing research conducted on waterborne disease over the past 10 years. Published in the July/August issue of the Journal of Water and Health, the collection is the result of the 1996 Safe Drinking Water Act (SDWA) amendments requiring that the EPA and the U.S. Centers for Disease Control and Prevention (CDC) conduct several waterborne disease studies toward the development of a national estimate of waterborne disease.
The SDWA-mandated studies were limited to gastrointestinal illness as the health effect of concern.
Research topics include:
- * Infectious disease risks associated with U.S. drinking water
- * The rate of acute gastrointestinal illness in developed countries
- * A review of household drinking water
- * Use of microbial risk assessment to inform the national estimate of acute gastrointestinal illness attributable to microbes in drinking water
- * An approach for developing a national estimate of waterborne disease due to drinking water and a national estimate model application
The purpose of the research papers is to review the state of the science, propose methodologies for estimating waterborne disease and the availability of data to make a National Estimate of Waterborne Disease.
For a review of the featured research papers, please go to:
Water System Lead Levels Linked to Disinfection Additive
The reported lead poisoning of a Durham, North Carolina boy has led health officials to suspect a coagulant used to remove organic matter from the local drinking water system as the most likely source of high lead levels in local tap water. The incident recalls similar water quality problems in the U.S where water treatment changes implemented to reduce disinfection byproducts have unexpectedly raised lead levels.
Durham County officials report they found more than 800 parts per billion of lead in tap water and no other source of lead in the boy’s home. The federal action level on lead content in public drinking water is set at 15 parts per billion.
Similar to incidents in Greenville, North Carolina and Stafford, Virginia, the Durham water system had switched to chloramines as a disinfection agent and also changed from alum (or another nonchloride coagulant) to ferric chloride in an effort to aid organic matter removal and limit the creation of disinfection byproducts. According to a corrosion engineering expert consulting on the incident, the adjustment increased the ratio of chloride to sulfate in the drinking water to the point that galvanic corrosion occurred, effectively eroding particles of lead solder from piping into local water supplies.
The episode has particularly alarmed water utility officials since Durham actively monitors its water quality, as required by the U.S. EPA’s Lead and Copper Rule, and those efforts failed to detect the problem.
According to the Stafford, Virginia water plant manager, the lead levels in that system quickly dropped below the EPA action limit after coagulants were changed by water system managers.
Shared Yoga Mats the Source of Skin Infections
According to a recent article in The New York Times, local doctors have seen a 50 percent spike in patients with athlete’s foot, plantar warts and staph infection. The suspected culprit? Unclean yoga mats.
According to Yoga Journal, 16.5 million people practiced yoga nationwide in 2005, up 43 percent from 2002. Local gyms are already known to be breeding grounds for viruses, fungi and bacteria resulting from shared equipment, excessive sweat and moisture in locker rooms. While research has not confirmed the link between unclean yoga mats and the infections, a handful of dermatologists and podiatrists interviewed report that in the last two years they have noticed a heightened number of skin infections in their patients who practice yoga and use public exercise mats.
Specialists warn that hygiene isn’t always a priority at some gyms and yoga studios, and that many cleaning solutions are not as effective as they should be. While alcohol or quat-based disinfectants are reportedly useful, Dr. Philip Tierno, renowned director of clinical microbiology at N.Y.U. Medical Center and author of “The Secret Life of Germs.” recommends the use chlorine as the surest way to kill bacteria on communal mats.
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.