Chlorine: Drinking water owes its safety largely to the addition of chlorine, which is used to kill the disease-causing bacteria and viruses found in untreated water. It also reacts with naturally occurring materials in water form disinfection byproducts. Prolonged exposure to these byproducts increases your risk of liver damage and cancer.
Flouride: In many areas, it is added to drinking water to promote dental health. Research has shown that prolonged exposure to excess flouride (more than the standard level of 4mg/L) may result in bone disease. For children under age nine, whose teeth are still developing, the EPA flouride standard is 2 mg/L.
Lead: Between the water treatment plant and your faucet, water may pass through corroded plumbing which can cause lead to leach into it. Children and pregnant women are most susceptible to lead-related health risks such as neurological damage, kidney and liver problems, and developmental delays in children.
Radon: Although regulated by public water utilities, radon may accumulate in underground water sources, a concern for those on private wells. Exposure to radon in drinking water and by inhaling the gas as it is released from the water during showers, washing, and laundering increases your cancer risk.
Volatile Organic Compounds: VOCs are commonly found in fuels, solvents, cosmetics, drugs, and dry cleaning solutions. They get into drinking water through improper industrial discharges that seep into ground water, a concern to those with wells. Health effects vary from eye, respiratory, and skin irritation to risk of cancer depending on the VOC and length of exposure.
Pharmaceuticals: Increasingly, these compounds are appearing in trace amounts in drinking water and are currently under study by the EPA to assess the long-term side effects as well as what treatment options may remove them from water supplies.
Nitrates: Run-off and improper disposal of synthetic fertilizers dump nitrates into the water system. They pose immediate threats to newborns because they interfere with the oxygen-carrying capacity of the child's blood.
More: EPA provides a comprehensive list of commonly found contaminants and evaluates water supplies for many major cities. Access to this information and more at www.epa.gov/safewater. If you have specific questions related to water quality, you can also contact The Safe Drinking Water Hotline at 800.426.4791 for assistance.
You can make your drinking water purer with a home filtration system. Your options include "point of entry" filters that treat water as it enters your home and "point of use" filters that treat water right before you drink it.
1. Carbon Filter
Removes: Chlorine, disinfection byproducts, pesticides, radon. Reduces heavy metals including copper, lead and mercury. Be certain to check model as all carbon filters do not perform the same filtration benefits.
Style Options: Countertop Pitchers, faucet filters and under-the-sink units.
Advantages: Generally low in cost and they retain minerals in water, which are beneficial to health.
Removes: Bacteria and heavy metals such as cadmium, chromium, copper, lead and mercury, as well as arsenic, barium, flouride, selenium, and sodium.
Style Options: Countertop or whole house point-of-entry units; can be combined with a carbon filter.
Drawbacks: Without carbon filter addition, does not remove chlorine, chlorine byproducts or VOCs. The process removes all minerals, leaving behind acidic water.
3. Reverse Osmosis
Removes: Most disease-causing bacteria, flouride, nitrates, asbestos, metals including lead.
Style Options: Under the counter point-of-use
Drawbacks: Without carbon filter, RO filters do not remove VOCs or chlorine. Removes all minerals resulting in acidic water.