Dr. Steve Oppenheimer's Warning on Reclaimed water:
Steve is Director CSUN Center for Cancer and Developmental Biology, a
Trustees Outstanding Professor, the California State University system; Fellow,
American Association for the Advancement of Science; Principal Investigator, NIH
NIGMS cell adhesion grant; Author or co-author of about 300 published papers,
abstracts and books, including 4 editions of Cancer, A
Biological and Clinical Introduction.
One thing that is not often mentioned is that we don't even have tests for thousands
of potential carcinogens, mutagens and toxins. So when someone tests water for
"safety", they usually just use the standard tests for
coliform bacteria, heavy metals and organics such as chlorinated compounds.
Recycled water, even recycled or reclaimed water that goes through
years of ground purification, may contain carcinogens, mutagens and toxins for
which we don't even have tests.
That's why the National Research Council's report on reclaimed water for potable
use stated that such water should only be used as an "option of last resort."
Drinking such water, in my opinion, is like playing Russian Roulette. It may be fine
for years, until a dangerous toxin, mutagen or carcinogen, for which
we have no tests, makes it through the reclamation process. In addition,
carcinogens, for example, may take decades to cause cancer. So short term studies
on water"safety" are next to useless, except to show that organisms, like
coliform bacteria that cause acute disease, are or are not present, or to show
that dangerous quantities of standard heavy metals or organics are or are not
present. Reclaimed water for potable use should be the "option of last resort."
Steve Oppenheimer, Ph.D.
Director CSUN Center for Cancer and Developmental Biology
Date: 8/23/2007 9:03:18 A.M. Pacific Daylight Time
Why do you think it is that wastewater sludge and reclaimed water scientists don't
know that coliform bacteria cause acute disease, including soft tissue and
Date: 8/23/2007 9:10:20 A.M. Pacific Daylight Time
Because coliform bacteria levels are so easy to analyse, that's not
the major problem. I think the major problem is the unknowns
in reclaimed water and that's why the National Resarch Council
said that reclaimed water for potable use should be the "option
of last resort."
The unknowns were outlined in a 1998 report, Issues in Potable Water Reuse, a
National Research Council committee concluded that reclaimed waste water can be
used to supplement drinking-water sources, but only as a last resort and after a
thorough health and safety evaluation. Municipalities first must fully assess health
impacts from likely contaminants and develop comprehensive systems for
monitoring, testing, and treatment. Other water sources and conservation measures
also should be tried to the extent practical, before turning to reclaimed waste water.
Because regulations for safe drinking water were not developed with reclaimed
water in mind, they may not be the best standard for testing its quality, the
committee said. Reclaimed water may contain sources of contamination that cannot
be determined through current testing or treatment processes.
Evaluate the potential health effects from possible contaminants. All major
sources of household, industrial, and agricultural chemical contaminants in
reclaimed water should be documented and removed based on existing federal
clean-water standards. Since it is unclear whether or not highly treated waste water
contains harmful levels of byproducts from disinfection processes such as
chlorination, this issue should be addressed by the research community. Most
outbreaks of waterborne disease in the United States are caused by parasites and
viruses, yet few drinking-water systems monitor for the full range of such pathogens.
Assess the health risks of drinking reclaimed water. After reviewing the few
studies that have examined the health implications of drinking reclaimed water, the
committee said that different approaches are needed to test the safety of reclaimed
water. Conventional toxicology tests developed by the food and drug industries are
not appropriate for evaluating the risks from complex chemical mixtures that can be
found in reclaimed water. Alternative studies, such as tests using fish in source
water, should be undertaken to provide a broader range of data about possible
harmful effects to living organisms. Research also is needed on the level of viruses
and parasites in all waters and the effectiveness of both conventional and
advanced water treatment processes in removing these pathogens. The federal
government should undertake population studies that compare the disease rates
over time among individuals exposed to reclaimed water to the disease rates among
individuals who use a different water source.
> Monitor the reliability and operation of water treatment systems. There are two
essential keys to the safe, reliable operation of a reclaimed-water treatment system:
good design that provides redundant safety measures to prevent contamination,
and monitoring systems that detect variations in water quality and system
performance. Other measures should be implemented as well. Since waterborne
viruses, bacteria, and parasites pose the greatest threat to public safety, water
treatment procedures for removing them should necessarily be the most stringent.
Communities using reclaimed water should implement well-coordinated, public
health surveillance systems to document and provide early warning of any adverse
health effects associated with the ingestion of reclaimed water.