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How does water pollution affect health?
Water pollution, even in water we don't drink,
is a serious threat to health. When certain Japanese companies released
mercury into the Pacific Ocean, they had no idea that it would build up in
the environment. It was not until 52 people from the village of Minamata
died and over 100 more became seriously ill that the mercury buildup was
discovered in the fish the people of the village were eating. Birth defects
continue to cripple the children of the village. Although the release of
mercury into the environment is now strictly regulated, there are
innumerable other chemicals that are not. The impact that many of these
chemicals will have on health is yet to be discovered. Others are already
identified as carcinogens, mutagens, and just plain poisons. Chemicals like
pentachlorophenol dioxin 5, trihalomethane, polychlorinated biphenyl (PCB),
and hundreds of others are seeping into groundwater and surface water all
over the country.
Some of these chemicals have already been
banned, and millions of tons of them have been dumped in over 10 thousand
toxic waste sites. We do not even know the location of many of the sites,
which are slowly spreading their boundaries as the poisons are leached out,
polluting the very ground much of our water comes from. These chemicals have
created a toxic waste nightmare that has barely been recognized. The
multibillion dollar federal Superfund program created to deal with toxic
wastes was extended by Congress but is inadequate even to clean up these
sites, let alone deal with the disastrous health effects that are sure to
result.
Since the 1940s, DDT has been the most popular
and effective pesticide ever used. The release of DDT into the environment
continued unabated for many years. Rain washed it from the fields into the
rivers and streams until it reached the oceans. It was consumed by
microscopic plankton, in turn consumed by shellfish, fish, and birds.
Through a process called biological magnification, chemicals passed up the
food chain accumulate at greater levels in the species near the top. Man,
consuming grains, fish, birds, and meats, is close to the very top of the
food chain.
DDT causes birds to lay eggs with very thin
shells; its presence in the food chain threatens to bring about the
extinction of the Bermuda petrel, the brown pelican, the osprey, and the
peregrine falcon. In man, DDT is suspected of being a carcinogen and a
mutagen. Not until 1969, when entire species of birds were threatened with
extinction, was DDT banned in the United States. Now, years after it was
outlawed, it shows up far away in the penguins of Antarctica, and we all
have traces of DDT in our bodies. Many foreign countries continue to use DDT
without control, and it still pollutes the environment through the
groundwater.
Should I drink water from the tap?
Maybe and maybe not. Our drinking water is
often referred to as the cleanest in the world. In some respects this is
true. If you are supplied with water from a metropolitan water supply,
bacteria such as Escherichia coli, the shigella groups, and those
responsible for typhus and cholera are routinely destroyed by chlorination.
Chlorine is added to the water in minute doses to kill these bacteria that
cause serious intestinal infections.
However, minute traces of pesticides and other
organic chemicals in the water supply may combine with the chlorine to form
extremely dangerous compounds called trihalomethanes. One of these compounds
is chloroform, a known carcinogen. In a 1975 study, the EPA found traces of
chloroform in the drinking water of all 80 cities it studied. Chlorinated
water has been associated with increased rates of rectal, colon, and bladder
cancer.
In most major cities, over a hundred organic
chemicals can be found in the drinking water. Using bottled or distilled
water may be a prudent idea, but be wary of the source of these "mountain
pure" waters. Some may come from wells that are no safer than sources of
city water. The laws governing the purity of bottled water are the same as
those that regulate tap water. And companies that recycle bottles may not be
as successful as you might think at cleaning them between uses. If a
gardener uses the water bottle to mix up a batch of insecticide, you may be
the unfortunate recipient of a nasty dose of poison.
Water filters are also an option. Be sure you
investigate the quality of any water filter system thoroughly. Filters that
screw on to the faucet are generally useless.
The wells that supplied public water to the
city of Woburn, Massachusetts, were found to be contaminated with extremely
high levels of chloroform, trichloroethylene, tetrachloroethylene, 1,1,1 -trichloroethylene,
and dibromochioromethane before they were shut down. These wells were
associated with a cluster of rare leukemias in the children of that town.
Can fluoride in the water system cause
problems?
Fluoride is added to many city water supplies
because it has been documented that it drastically improves the dental
health of a community by reducing cavities. About the only time fluoride
causes health problems is when the amount is excessive. This rarely happens
because of the minute amounts added to a monitored city water system. The
occasional problem is in a private well where high levels of fluoride may
occur naturally. Private wells should be checked regularly, and for more
than fluoride content. The great amounts of pesticides and other chemicals
used by farmers and state and federal governments have resulted in the
pollution of many rural wells.
What about swimming in polluted water?
If the health department has posted signs
indicating the water is polluted, don't risk your health by swimming there.
Polluted water is usually contaminated by bacteria and viruses from raw
sewage. This happens when a sewage treatment facility overflows or when a
heavy rain washes effluent off the streets and fields into lakes and the
ocean. Such diseases as hepatitis and severe gastrointestinal upsets can
result.
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