Safe Drinking Water
(Page 6 of 6)
June/July 2003
By Lynn Keiley
Although nitrates occur naturally, high levels often are a problem in farming areas or in places where there is a high concentration of septic systems. Wastewater, fertilizers and fecal matter, from humans and other animals, all can be sources of nitrates. Although adults can tolerate high levels reasonably well, nitrates can be very dangerous for infants, reducing their blood's ability to carry oxygen and causing methemoglobinemia, or blue-baby syndrome.
RELATED CONTENT
On-demand water heaters provide an “endless supply” of hot water, but are they really “green”? Ther...
Conventional water heaters heat water and store it until it’s used, but a lot of that heat is waste...
Energy and water spending bill clears for Obama's pen, homeland security bill next...
Your woodstove can heat more than your home. This hot water heating system uses extra heat to produ...
There are several types of solar water heating systems. Learn more using solar energy to heat water...
Pesticides
Pesticides, particularly popular weed killers such as atrazine, have been found in nearly every stream tested in the United States. Atrazine and other herbicides, such as 2,4-D, are commonly found in groundwater. Federal drinking-water laws allow minute quantities of pesticides in municipal water. Debate continues about the possible health effects of these legal amounts of pesticides in our drinking water.
Arsenic
Arsenic finds its way into water supplies from both natural sources and human activities. In some places, particularly the Southwest, arsenic leaches into the water from certain types of rock. Gas- and oil-well drilling and gold mining are other sources of arsenic contamination. Although prolonged exposure to arsenic has been shown to cause several forms of cancer, until recently just how much of it poses a human health risk has been a source of heated debate. Bowing to new scientific evidence and public pressure, the federal government has finally agreed to lower the acceptable amount from 50 parts per billion (ppb) to 10 ppb, beginning January 2006. Chronic exposure to low levels of arsenic can cause cancer, skin lesions, circulatory problems and nervous-system disorders.
Minerals
In water supplies, copper, iron and manganese pose more of a nuisance than a health threat. (These three minerals are essential trace nutrients in our bodies, but they must be consumed in amounts that do not exceed a toxic threshold.)
Iron often imparts a metallic taste and leaves telltale orange-brown stains on clothes and linens. Manganese behaves similarly, affecting taste and producing blackish stains. Copper usually originates from highly acidic water, which corrodes copper plumbing. Besides its metallic taste, in high concentrations, copper can cause stomach cramps and intestinal illness. You'll find its signature blue-green stains in sinks and bathtubs.
Page:
<< Previous 1 |
2 |
3 |
4 |
5 | 6 |
