|  | Public Health Safety | Environmental Health

About Chemical Water Treatment

Water is capable of causing viral and bacterial infections that affect the gastrointestinal tract when the water is dirty and not treated. Chemicals that treat water aid in removing the pathogens that can cause these viral and bacterial infections. There are several chemical water treatments available and used today. These chemical water treatments include halazone tablets, chlorine, iodine and peroxide.

  1. How the Chemicals Work

    • The chemicals used to treat water are capable of eliminating several different types of bacteria. The contact time, water temperature and chemical concentration will determine the chemical's effectiveness. If the temperature and chemical concentration are low, it will take more contact time for water to become clean and disinfected. Chemical water treatments are effective in killing certain chemical viruses and amoeba and Giardia cysts (types of bacteria).

    Chlorine

    • Chlorine is a common chemical water treatment. It is found in the drinking water and other household water in developed countries. It is capable of killing of dangerous bacteria without being dangerous to humans in the water in developed countries. It has been used for centuries as an effective water disinfectant.

    Halazone Tablets

    • Halazone tablets are inexpensive and easy-to-use chemical water treatment. These tablets are added to water and must stay in the water for one hour to be effective. Six tablets can disinfect just 1 liter of water. Halazone tablets are only effective for a short time and become quickly ineffective when exposed to air that is humid and warm.

    Superchlorination-Dechlorination

    • Superchlorination-dechlorination is a chemical water treatment method that requires two steps. This highly effective chemical water treatment requires an initial dose of chlorine in high concentrations. In the second step, peroxide is added to remove the chlorine. This chemical water treatment method is considered inconvenient, but highly effective in disinfecting water.

    Iodine

    • Iodine has been used as a chemical water treatment for approximately a century. It is effective as a short-term water disinfectant, but the disinfecting capabilities diminish over time and generally only last three to six months. Iodine should not be used as a long-term water disinfectant. This chemical is also harmful to those with thyroid disease, an iodine allergy and to pregnant women and should not be used by them. Iodine has been shown to be effective in killing the diarrhea-causing bacteria, cyclospora. Iodine used as a chemical water treatment comes in several preparations including tetraglycine hydroperiodide, iodine topical solution, povidone-iodine, Lugol's solution and iodine tincture.

Environmental Health - Related Articles