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What
You Should Know About VOCs in Your Drinking Water
Volatile Organic Compounds, or VOCs, are chemicals —
like industrial solvents, herbicides, pesticides, and some
petroleum products — that are used frequently in the
U.S. Sometimes, these VOCs contaminate drinking water by migrating
into aquifers from industrial spills, tank leaks, or agricultural
runoff. EPA estimates that VOCs are present in one-fifth of
the nation's water supplies. An estimate provided by the Environmental
Working Group, a non-profit organization based in Washington,
D.C., suggests that 14.1 million people drink water contaminated
with five major agricultural herbicides, only three of which
are regulated by EPA.
* What are VOCs?
* What health problems do VOCs cause?
* How do VOCs get into drinking water?
* Don't water treatment plants remove VOCs?
* Are VOCs in well water?
* What is EPA doing to control VOCs in drinking
water?
* What can you do?
What
are VOCs?
VOCs are organic chemicals that easily vaporize at low, or
what we think of as "room," temperatures. They are
called "organic" because they contain the element
carbon in their molecular structures. VOCs may be found in
drinking water throughout the U.S. But since many VOCs have
no color, smell, or taste, they are difficult to readily detect
in drinking water.
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What
health problems do VOCs cause?
At high levels, VOCs may cause:
* Cancer;
* Kidney, liver, and brain damage; and
* Nervous, reproductive, and immune system damage.
Some VOCs act as "endocrine impostors," which means
that they mimic hormones. The human body thinks that they
are hormones and lets them trigger the same biological reactions
that real hormones cause. These reactions then wreak havoc
on the brain, immune, and reproductive systems.
Infants and children are particularly at risk to VOCs in
drinking water because:
1) they are growing, and 2) they drink more water per pound
body weight than adults. This means that their bodies have
to absorb more chemicals per pound than adults and that VOCs
may affect the way they grow.
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How
do VOCs get into drinking water?
VOCs can migrate into ground water sources from accidental
industrial spills, leaks from underground storage tanks containing
these chemicals, and illegal dumping. Since many VOCs are
herbicides and pesticides, agricultural runoff is also a major
source of contamination. Herbicide and pesticide contamination
is typically highest in the spring and summer. Also, VOCs
are often created when drinking water is chlorinated. Called
disinfection byproducts (DBPs), these VOCs also have the potential
to cause cancer in humans.
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Don't
water treatment plants remove VOCs?
According to the Environmental Working Group, the only reliable
technology that effectively removes VOCs from drinking water
is activated carbon. But many water utilities use only sand
filters to clarify drinking water and chlorine to disinfect
it. Furthermore, of the thousands of organic chemicals in
use today, EPA regulates just over 50. More regulations are
on the way, but they still will not cover the complete spectrum
of organic chemicals that can potentially pose a threat to
human health.
To find out which types of treatment techniques your water
treatment plant uses to purify water, call them. Their number
should be listed on your water bill.
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Are
VOCs in well water?
Since VOCs are so ubiquitous and come from so many different
sources, private well water is not necessarily safe from contamination.
In particular, wells near farms may contain unacceptable levels
of herbicides and pesticides.
To have your well water tested for VOCs, call a water testing
laboratory. Look under "Water Analysis" in the Yellow
Pages for a lab near you, or contact your state or local health
department. Tests for VOCs can be expensive (e.g., $100 to
$300 per sample). However, some local health departments test
private well water for free. Look under the government listings
in your phone book for their number.
If you call a water testing lab, be sure it is certified by
your State. You may call your State Certification Officer
to get a list of certified water testing labs in your state.
Click here to find out how to contact your State Certification
Officer.
Remember: A water test will only tell you what is in your
water that day. Many pollutants or public water treatment
plant failures can occur intermittently (e.g., after pesticide
and herbicide spraying) and not necessarily the day your are
having your water tested.
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What
is EPA doing to control VOCs in drinking water?
Currently, EPA regulates over 50 organic chemicals, including
lindane (a pesticide) and atrazine (a herbicide). The agency
has also identified another 50 organic compounds, almost half
of which are pesticides, that it will consider regulating
in the future.
But according to the Environmental Working Group, the federal
drinking water standards are weak, particularly when it comes
to VOCs. They do not take into account the significance of
seasonal peaks in exposure (such as the spring and summer
when herbicide and pesticide exposure is highest), nor do
they account for the levels infants and children can tolerate.
Furthermore, the regulations do not incorporate degradation
products that naturally occur as VOCs degrade into other compounds
in the environment. Many of these breakdown products are toxic
also.
The most effective method of ensuring that drinking water
is free of VOCs is to protect water sources from contamination.
Through the Wellhead Protection Program, a program laid out
in EPA's National Drinking Water Program Redirection Strategy
(released June 7, 1996), one of EPA's goals is to help communities
prevent further pollution of their drinking water sources.
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What
can you do?
If you think your drinking water may be contaminated with
VOCs, or if you are concerned about the possible health effects
of contamination, you should consider the following options:
1. Installing a filter under your sink that is certified by
the National Sanitation Foundation for VOC reduction. The
filter cartridge should be made of carbon (either activated
carbon or a carbon block).
OMNI's CBF3 and OT32 filters are NSF certified for VOC reduction.
2. Purchase bottled water, but be sure this water had been
adequately treated. This is a more expensive and not necessarily
effective option.
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