Drinking Water: Filter or Purify

Is Your Water Fit to Drink?

A simple guide to treatment systems

It Came from the Faucet

Lead, which can lower children's IQs and cause developmental delays; in adults it can boost blood pressure and cause kidney problems

Potential carcinogens, including arsenic, asbestos, radium, benzene, trichloroethylene, radon, the pesticide atrazine, and perchlorate, a chemical known for causing thyroid tumors and, in fetuses and infants, delaying development 

Germs, including cysts such as Giardia and Cryptosporidium; fecal bacteria such as fecal coliform; and viruses. These are a particular risk for infants and anyone with a weakened immune system, including those with HIV, transplant recipients, chemotherapy patients, and the frail elderly

By-products of chlorination, such as trihalomethanes and haloacetic acids, which may cause cancer, reproductive problems, and birth defects

Nitrate (from fertilizers and animal and human waste), which can interfere with the blood's ability to carry oxygen and is especially hazardous for infants; it also may be linked to miscarriages and birth defects

Heavy metals, such as mercury and cadmium, which may cause kidney and neurological damage

   Treat Your Water Right
   Activated granular carbon filters Atrazine, benzene, mercury, trichloroethylene, trihalomethanes, and radon
Note: These filters may include other materials, in addition to carbon, that remove additional contaminants, such as lead.
Pitchers*, faucet-mounted, undersink, and whole-house From about $20 for faucet-mounted to $1,800 for whole-house   
   Solid block carbon filters Asbestos, atrazine, benzene, lead, mercury, trichloroethylene, trihalomethanes, Giardia and Cryptosporidium Pitchers*, faucet-mounted, and undersink From about $30 for faucet-mounted to $400 for undersink   
   Reverse osmosis systems Arsenic, asbestos, atrazine, lead, mercury, nitrate, radium, Cryptosporidium, and fluoride
Note: These systems usually include carbon filters that also remove benzene, radon, trichloroethylene, and trihalomethanes.
Faucet-mounted and undersink $200 to $1,000   
   Distillers Arsenic, asbestos, lead, mercury, nitrate, trichloroethylene, trihalomethanes, radium, coliform bacteria, Cryptosporidium, and fluoride
Note: These usually include charcoal filters that also remove atrazine, benzene, and radon.
Faucet-mounted and undersink $100 to $500   
   Ion exchange systems (aka water softeners) Calcium and magnesium (minerals that shorten the life of household plumbing and make it harder to rinse away soap residue)
Note: Some ion exchange systems also remove iron, manganese, aluminum, lead, and radium. Anion exchange systems, a variation on ion exchange systems, may remove arsenic, nitrate, mercury, sulfate, and perchlorate, in addition to the contaminants ion exchange systems remove.
Whole house $800 to $2,500   
   *Pitchers range from about $20 to $45.   
Published November 2011, Prevention
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