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Week of 6.30.06

Top Hazardous Chemicals

Below is a description of three hazardous chemicals often transported throughout the United States by rail and truck. Government studies suggest that the explosion of one tanker car carrying chlorine, for example, could cause up to 100,000 deaths in a densely populated area.

In 1991 a five alarm fire onboard the OMNISEA fish processing boat threatened to release up to 12,000 pounds of ammonia into the environment from a Seattle pier.
In 1991 a five alarm fire onboard the OMNISEA fish processing boat threatened to release up to 12,000 pounds of ammonia into the environment from a Seattle pier. (Image courtesy of NOAA)
Ammonia (gas): A colorless gas with a strong odor.

Used for: Making fertilizer, plastics, dyes, textiles, detergents and pesticides.

Risks: Acute ammonia exposure can cause skin irritation; burn the eyes, resulting in temporary or permanent blindness; and cause headaches, nausea and vomiting. High levels can cause fluid in the respiratory system, which can cause death. Chronic exposure damages the lungs.

Substitute: Available. Several companies have switched from gas ammonia to liquid ammonia, a safer alternative. Manhattan Products of Carlstadt, NJ, a mid-sized manufacturer of household ammonia cleaners is one company that made the switch. The change created a safer workplace and eliminated the chance of a toxic release affecting many of 160,000 people who live within the facility's former vulnerability zone, according to a report by the Center for American Progress.


In 2005, two transport trains collided in Graniteville, SC, releasing at least 90 tons of  chlorine gas into the air. At least 250 people were treated for chlorine exposure and the nearby area was evacuated for nearly two weeks.
In 2005, two transport trains collided in Graniteville, SC, releasing at least 90 tons of chlorine gas into the air. At least 250 people were treated for chlorine exposure and the nearby area was evacuated for nearly two weeks. (Image courtesy of EPA)
Chlorine (gas): A greenish-yellow gas with a strong odor.

Used for: Making disinfectant chemicals in bleaching products and for purifying water and sewage.

Risks: Acute exposure to chlorine can severely burn the eyes and skin, causing permanent damage, and may cause throat irritation, tearing, coughing, nose bleeds, chest pain, fluid build-up in the lungs and death. A single high exposure can permanently damage the lungs. Chronic exposure can damage the teeth and irritate the lungs causing respiratory problems.

Substitute: Available. Many water utilities have switched from chlorine gas to ultraviolet light for water treatment. The use of ultraviolet light eliminates the hazards of transporting and working with chlorine gas.


Necrosis on a grape leaf caused by hydrogen fluoride emitted from an aluminum plant. Photo: W. Gartel, Copyright American Phytopathological Society
Necrosis on a grape leaf caused by hydrogen fluoride emitted from an aluminum plant. Photo: W. Gartel © American Phytopathological Society
Hydrogen Fluoride: A corrosive colorless fuming liquid or gas with a strong irritating odor.

Used for: Making other chemicals, including gasoline, and for etching glass.

Risks: Breathing hydrogen fluoride causes extreme respiratory irritation, including cough, fever, chills and tightness, which may be fatal. Contact can burn the skin and eyes badly, resulting in permanent eye damage or blindness. Long term exposure may damage the liver and kidneys, and cause other illnesses.

Substitute: Available. Two-thirds of the refineries in the U.S. already use safer alternatives to hydrogen fluoride such as sulfuric acid, which is less dangerous but not danger free. Paul Orum, of the Center for American Progress said many companies have not switched because of high costs associated with using sulfuric acid.

Success Stories since 9/11

At least 225 industrial plants in the country have switched to less dangerous chemicals since the 2001 terrorist attacks, according to a new study. This has lowered the risk for millions of people that would be injured or killed by toxic plumes.

But these plants represent a small fraction of the estimated 14,000 nationwide that store or use large quantities of extremely hazardous substances.

In a report released in April 2006, The Center for American Progress, a research and advocacy group, found 450 of these facilities each put "more than 100,000 people in harm's way."

For more success stories see the full report "Preventing Toxic Terrorism," available at The Center for American Progress.

Cleveland Water Eliminates Chlorine

In 1999 the Cleveland Division of Water (CWD) began the transition from chlorine to sodium hypochlorite by discontinuing the use of chlorine rail cars at two water treatment plants. After September 11, 2001, the CWD discontinued the use of all chlorine rail cars due to fears that chlorine could be used as a weapon by terrorists. By 2010, CWD will have finished its transition from chlorine to sodium hypochlorite - a safer alternative -- as its disinfectant.

For more, see Chemical Safety and Security, Environmental Health Watch