Health and Environment
Acute (Short-Term) Health Effects
Chlorine poses the greatest potential for harm to human health through acute exposure.
- Chlorine is an extremely corrosive gas. It will burn skin, eyes, nose, throat, lungs, and even teeth at doses as low as 15 parts per million (ppm).
- At doses of 25 ppm, chlorine may burn the lungs, cause fluid buildup (pulmonary edema), and result in death.
- A chlorine gas leak at an industrial or wastewater treatment facility poses a serious hazard to worker and public health.
Chronic (Long-Term) Health Effects
- The lungs are the primary organs effected by chronic chlorine exposure. Repeated exposure to chlorine may result in bronchitis or pneumonia.
- No information is available on the carcinogenic or teratogenic (reproductive) effects of chlorine on humans. Animal studies have failed to identify any carcinogenic or teratogenic effects from chlorine exposure.
Ecological Health Effects
- Chlorine is extremely toxic to aquatic organisms; less than 0.1 micrograms of chlorine per liter of water has killed 50% of the exposed aquatic organisms.
Facilities using chlorine must minimize worker exposure and take precautions to avoid fires and leaks.
- Use chlorine in closed systems. If a closed production system is infeasible, facilities need to enclose operations and use local exhaust ventilation. Where the potentialfor exposure to chlorine exceeds 0.5 ppm use a Mine Safety and Health Administration/National Institute for Occupational Safety and Health-approved supplied air respirator with a full facepiece.
- Take precautions to avoid chlorine contact with skin and eyes.
- Outside the daily routine, leaks and fires pose the greatest threat to workers. As a gas, chlorine is stored under pressure and has the potential to leak. While not a flammable or reactive chemical, chlorine containers may explode and release poisonous gases during fires.
- Leaks and fires pose the greatest direct threats to public health. In fact, to eliminate the chlorine hazard some cities now use alternative disinfectants for wastewater treatment.
- Toxic byproducts result from chlorine use in water purification systems and products. Trihalomethanes (THMs) form during water purification when chlorine reacts with natural and synthetic organic chemicals in the water. Research by the Centers for Disease Control and the New Jersey Department of Health identified potential associations between high THM levels in drinking water and low birth weights and birth defects.
- The burning of chlorine-containing products (such as PVC) in incinerators releases dioxins and furans into the ambient environment.
The data in this section were collected from the following sources: Richard J. Lewis, Sr. (ed.), 1993, Hazardous Chemicals Desk Reference (third edition) (New York: Van Nostrand Reinhold); New Jersey Department of Health, 1991, "Chlorine" (Trenton, New Jersey -- see the webpage: http://www.rkt.net); Swedish National Chemicals Inspectorate (KemI), 1995, Chlorine and Chlorine Compounds: Use, Occurrence and Risks -- The Need for Action (Report No. 1/95; Solna, Sweden: KemI); Swedish National Chemicals Inspectorate (KemI), 1995, Chlorine and Chlorinated Compounds: Survey of Fluxes to and in the Environment, Pools in the Environment and Health and Environmental Risks (Report No. 5/95; Solna, Sweden: KemI); and U.S. EPA, Office of Air Quality Planning and Standards, 1998, "Chlorine" (Washington, D.C.: U.S. EPA -- see webpage: http://www.epa.gov/ttn/uatw/hlthef/chlorine.html).