Many of us take the quality and purity of our water for granted. While the public water supply is generally safe for most people, it is not always as harmless as we’d like to believe. In addition to additives like chorine and fluoride, tap water may contain various minerals, microorganisms, and chemicals. Regulating Water Quality The Environmental Protection Agency (EPA) closely monitors the quality of public drinking water. Monitoring must adhere to the Safe Drinking Water Act, which specifies the method for choosing which contaminants are monitored and determining what contaminant levels are acceptable. Sometimes, the acceptable level is set at zero, but water treatment plants cannot always achieve this level of purity. This disparity is especially common for contaminants that pose a particular hazard for children, the elderly, and people with weakened immune systems. Currently the EPA monitors approximately 90 different substances. However, over 260 different substances have been found in U.S. tap water. Some of these may simply be a nuisance, while others can pose a health risk. Meanwhile certain contaminants, such as lead, may be introduced through plumbing in individual households. Common Tap Water Contaminants Although the contaminants present in public water may vary widely among municipalities, they generally fall into five categories.
- Microorganisms: Both bacteria and viruses may be present in tap water. Chlorine is added to water to kill microorganisms; it kills the vast majority of bacteria and most viruses. Because viruses are so small, they can be difficult to detect. Parasites may also contaminate water, causing gastrointestinal problems for healthy people.
- Metals and minerals: These may be introduced at any step of the water distribution process. Water sources close to mining facilities are most likely to be contaminated with these substances.
- Organic chemicals: Over 100,000 commercial chemicals have been detected in water, from pesticides and fertilizers, to dyes and pharmaceuticals. When organic chemicals mix with water, they can form VOC’s or THM’s. These compounds can infiltrate the body through contact, inhalation, or drinking.
- Radioactive substances: As they decay, radioactive contaminants also release radon gas, which also poses a health threat. Although this sort of contamination is relatively rare, it does sometimes occur.
- Additives: Public water suppliers routinely add substances like chorine and fluoride to water. Chorine is added to kill microorganisms, and fluoride improves dental health. People who prefer non-fluoridated water can filter their water or buy water that does not contain fluoride.
Many common contaminants can be significantly reduced or completely removed with a high-quality residential water filter system. Check your annual water quality report or test your water to determine whether a water filtration system makes sense for you and your family.