[Pharmwaste] Man-Made Chemicals Found in Drinking Water at Low Levels

DeBiasi,Deborah dldebiasi at deq.virginia.gov
Fri Dec 5 11:06:46 EST 2008



News Release

U.S. Department of the Interior
U.S. Geological Survey

For release:  December 5, 2008

Contact:
Greg Delzer, 605-394-3230, gcdelzer at usgs.gov
Jennifer LaVista, 202-380-6052, jlavista at usgs.gov


Man-Made Chemicals Found in Drinking Water at Low Levels

Low levels of certain man-made chemicals remain in public water supplies
after being treated in selected community water facilities.

Water from nine selected rivers, used as a source for public water
systems, was analyzed in a study by the U.S. Geological Survey (USGS).


"Most of the man-made chemicals assessed in the USGS study are
unregulated in drinking water and not required to be monitored or
removed," says Tom Jacobus, General Manager of the Washington Aqueduct.
"These findings are not surprising and they will be important in helping
regulators and assisting water utility managers arrive at decisions
about future water treatment processes."

Scientists tested water samples for about 260 commonly used chemicals,
including pesticides, solvents, gasoline hydrocarbons, personal care and
household-use products, disinfection by-products, and manufacturing
additives. This study did not look at pharmaceuticals or hormones.

Low levels of about 130 of the man-made chemicals were detected in
streams and rivers before treatment at the public water facilities
(source water). Nearly two-thirds of those chemicals were also detected
after treatment. Most of the chemicals found were at levels equivalent
to one thimble of water in an Olympic-sized pool.

"Low level detection does not necessarily indicate a concern to human
health, but rather indicates what types of chemicals we can expect to
find in different areas of the country," said USGS lead scientist,
Gregory Delzer. "Recent scientific advances have given USGS scientists
the analytical tools to detect a variety of contaminants in the
environment at low concentrations; often 100 to 1,000 times lower than
drinking-water standards and other human-health benchmarks."

Testing sites include the White River in Indiana; Elm Fork Trinity River
in Texas; Potomac River in Maryland; Neuse River in North Carolina;
Chattahoochee River in Georgia; Running Gutter Brook in Massachusetts;
Clackamas River in Oregon; Truckee River in Nevada; and Cache La Poudre
in Colorado. The populations in communities served by these water
treatment plants vary from 3,000 to over a million.

This study is among the first by the USGS to report on a wide range of
chemicals found before and after treatment. The full source-water
quality assessment ( http://water.usgs.gov/nawqa/swqa ) and listing of
chemicals are available online.

Chemicals included in this study serve as indicators of the possible
presence of a larger number of commonly used chemicals in rivers,
streams, and drinking water. The most commonly detected chemicals in the
source water were herbicides, disinfection by-products, and fragrances.
Many of these chemicals are among those often found in ambient waters of
186 rivers and streams sampled by USGS since the early 1990s, and are
highly correlated with the presence of upstream wastewater sources or
upstream agricultural and urban land use. About 120 chemicals were not
detected at all.

Measured concentrations of chemicals detected in both source and treated
water were generally less than 0.1 part per billion. Although potential
human-health effects and risk were not assessed in this study, adverse
effects to human health are expected to be negligible based on
comparisons of measured concentrations and available human-health
benchmarks.

More than 75 percent of source- and treated-water samples in this study
contained 5 or more chemicals. The common occurrence of chemical
mixtures means that the total combined toxicity may be greater than that
of any single contaminant present. The USGS report identifies the need
for continued research because the additive or synergistic effects on
human health of mixtures of man-made chemicals at low levels are not
well understood. The study also did not look at implications to
ecosystems or aquatic health.

USGS findings are used by the U.S. Environmental Protection Agency, the
States, utilities and many nongovernmental agencies to help protect
streams and watersheds that serve as water supplies and to guide those
involved in decisions on treatment processes in the future.

The USGS is a non-regulatory agency which often monitors the quality of
available, untreated water resources. These studies begin to relate the
quality of these resources to drinking water. USGS studies are intended
to complement drinking-water monitoring required by Federal, State, and
local programs, which focus primarily on post-treatment compliance
monitoring.

The USGS National Water-Quality Assessment Program is planning to
complete as many as 21 additional surface-water assessments through 2013
( http://pubs.usgs.gov/fs/2007/3069/ ). A companion study is scheduled
for release in 2009 that summarizes the occurrence of the same chemicals
in high-production wells and the associated treated water in 13 states.

USGS provides science for a changing world. For more information, visit
www.usgs.gov.

Subscribe to USGS News Releases via our electronic mailing list at
http://www.usgs.gov/newsroom/list_server.asp or our RSS feed at
http://feeds.feedburner.com/UsgsNewsroom..

                          **** www.usgs.gov ****



Deborah L. DeBiasi
Email:   dldebiasi at deq.virginia.gov
WEB site address:  www.deq.virginia.gov
Virginia Department of Environmental Quality
Office of Water Permit Programs
Industrial Pretreatment/Toxics Management Program
PPCPs, EDCs, and Microconstituents
Mail:          P.O. Box 1105, Richmond, VA  23218 (NEW!)
Location:  629 E. Main Street, Richmond, VA  23219
PH:         804-698-4028
FAX:      804-698-4032



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