ANHYDROUS ammonia released from a tanker during a traffic incident in Teutopolis, US, is believed to have killed five people and hospitalised a further seven. Hundreds of residents were also evacuated as a precaution but were allowed to return home some hours later when it was determined the danger to the area had passed.
Preliminary information from the National Transportation Safety Board (NTSB) indicates that the incident, which occurred on 30 September, was caused when a car attempted to overtake a truck operated by Prairie Land Transport, loaded with the chemical. “The driver of the truck appears to have reacted by pulling to the right,” said Tom Chapman at NTSB. “The tanker truck departed the roadway. After it departed the roadway, the truck rolled over, and the cargo tank was compromised."
Of the five that died, three were from the same family − one adult and two children − while the other two were adult motorists from out of state, said Effingham County coroner Kim Rhodes.
Clayton Kuetemeyer, deputy director of emergency management for the state of Illinois, said: "We offer our deepest sympathies to all those affected by the accident and chemical spill. First responders and emergency managers train for this and many other kinds of emergencies with the goal of minimising impact to people and property."
Ammonia (NH3) is a source of nitrogen for plants and animals and is widely used in the production of fertiliser. More than 80% of anhydrous ammonia (without water) produced in the US is used for agricultural purposes. Typically, it is stored as a liquid under pressure, but because it contains little or no water, when it is released to the environment, anhydrous ammonia aggressively seeks out moisture and can form large, toxic vapour clouds when it comes into contact with ambient air.
When reacted with water, anhydrous ammonia can form ammonium hydroxide – a pungent liquid caustic that can quickly dehydrate living tissue and destroy cells on contact. Essentially, any tissue containing moisture that is exposed to it, is chemically burned.
According to local news, approximately 15,000 L of ammonia was released during the accident, causing a large gaseous cloud to form. Emergency crews worked overnight in windy conditions to control the plume from the leak, with residents within a 1.6 km area evacuated.
The NTSB said its investigation now centres around the tank’s crashworthiness and the routing of the hazardous materials. A preliminary report is expected within 30 days, but the full report could take up to two years to complete, Chapman said.
According to the US Environmental Protection Agency (EPA), there are 150 serious chemical incidents a year in the US, but this could be an underestimate. Last year, the Coalition to Prevent Chemical Disasters recorded 188 incidents, up from 177 in 2021, while in 2023, there have already been at least 251 chemical incidents reported.
The EPA said it continues its efforts to reduce risks of accidental releases at industrial and chemical facilities, by imposing judicial actions, administrative penalty actions, and administrative compliance orders, but concedes that accidental releases “remain a significant concern”.
While most accidents occur close to or at a facility, transportation-related incidents outside of industrial plants do occur, including the controversial East Palestine, Ohio train accident in the US in February. The accident, which saw 38 carriages derail, 11 of which were carrying hazardous materials, occurred next to a town of 4,700 residents.
Although there were no reported fatalities or injuries, a number of chemicals were released into the air, surface soil and waters, including vinyl chloride, butyl acrylate, ethylhexyl acrylate, and ethylene glycol monobutyl ether.
Despite assurances from the EPA that it had not detected contaminants at “levels of concern” in and around East Palestine, an estimated 3,500 fish died in a 12 km stretch of a nearby stream contaminated by the crash, while residents continued to complain of rashes, nausea, headaches and dizziness two weeks after the incident.
Jennifer Homendy, the NTSB chair, lambasted the East Palestine derailment, deeming it “100 percent preventable”.
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