Chlorine is a yellow-green, poisonous, gaseous compound with a pungent odor and a high potential for irritation. It is most often used as a water purification agent or as a bleaching and/or disinfection tool. When ingested in the liquid form, chlorine can lead to several types of cancer, including bladder, rectal, and breast cancer. When inhaled in the gaseous form, chlorine is a known cause and/or irritant of the respiratory conditions asthma and bronchitis. In addition, dermal absorption of chlorine can cause severe skin irritations.
Cryptosporidium is a protozoan microbiological contaminant that is resistant to the disinfecting capabilities of chlorine. Ingestion of cryptosporidium generally leads to gastrointestinal illness.
Lead is a heavy metal substance used in several types of piping and as an additive in paint. It most typically makes its way into drinking water through the corrosion of household plumbing systems or the erosion of natural deposits into surface water sources. Ingestion of lead in drinking water has both short-term and long-term effects. Short-term exposure to lead in adults can interfere with red blood cell chemistry and increase blood pressure. Long-term exposure can result in kidney failure and/or stroke. Lead ingestion in children can cause severe physical and mental developmental delays.
Methyl-t-butyl ether (MTBE) is a member of a group of chemicals generally called fuel oxygenates. MTBE is typically added to unleaded gasoline to reduce its carbon monoxide and ozone content. MTBE makes its way into drinking water through several sources, including leakage of underground storage tanks, fuel spills, emissions from marine engines, and, to a small extent, condensation of exhaust fumes. Because MTBE is a relatively new contaminant, the EPA is currently conducting tests to clarify the potential health effects of ingesting MTBE in drinking water.
THMs (trihalomethanes) are chemical compounds that are formed as a result of a reaction between organic materials in drinking water and chlorine added as a disinfectant. THMs are one of the many byproducts of water chlorination. When ingested in drinking water, THMs can cause a host of physical problems. THMs are known carcinogens and leading causes of bladder and rectal cancer. THMs can adversely affect nervous system functioning, as well as trigger liver and kidney malfunctions. Ingestion of THMs in drinking water has also been linked to spontaneous abortion, or miscarriage, in pregnancy.
VOC (volatile organic chemical) is the umbrella term for a large number of synthetic chemicals found in drinking water. These chemicals were first discovered in drinking water in 1977 and have now been identified as present in the water of 33 states. VOCs make their way into water through a variety of sources, including septic system cleaning, weed and pest control, fumigation, and dry cleaning. When ingested, VOCs are known to cause cancer, adversely affect liver and kidney functioning, and disrupt nervous system performance. When inhaled or dermally absorbed, VOCs can severely irritate the tissue of the lungs and the skin.