The April 17 explosion at a fertilizer plant in West, Texas, that killed 15 people and injured 200 was perhaps one of the most severe chemical accidents of its kind in recent memory, but it was by no means the first.

Earlier this month, for example, Tyson Foods and its affiliates agreed to a $4 million civil settlement with the Environmental Protection Agency (EPA) and the Justice Department for violations of the Clean Air Act at 23 facilities in Iowa, Kansas, Nebraska and Missouri where the toxic chemical anhydrous ammonia was released during several occasions between 2006 and 2010, causing property damage, multiple injuries to workers and one death.

The Tyson incidents did not involve a massive explosion like the disaster in Texas, but the accidents have one potentially deadly element in common: anhydrous ammonia.

Investigators now believe that large stores of ammonium nitrate caught on fire and caused the explosion at the West plant. But the plant also held two 12,000-gallon tanks of anhydrous ammonia that could have exacerbated the disaster in Texas if they leaked or exploded, according to the Center for Effective Government (CEG).

Anhydrous Ammonia Accidents

During the past 15 years, 1,000 accidents have occurred nationwide at chemical facilities that hold large quantities of anhydrous ammonia, according to data recently compiled by CEG.

Anhydrous ammonia is a poisonous gas that, like ammonium nitrate, is used to make fertilizer. The chemical is also used as an industrial refrigerant. The EPA considers anhydrous ammonia to be “extremely hazardous” and the chemical can explode if heated. Exposure to low levels of the chemical can cause burning of the eyes and exposure to higher levels can cause blindness, chemical burns and even death.

Currently, about 8,000 facilities nationwide store 10,000 or more pounds of anhydrous ammonia and are required to submit risk management plans to the government. Another 2,000 have deregistered from the government’s list, possibly because they hold less than 10,000 pounds, but may still store the chemical.

In the past 15 years, 1,000 accidents have occurred at 678 of these facilities, and multiple accidents have occurred at 133 facilities, according to CEG. Many of the accidents directly involved anhydrous ammonia releases, spills and fires. Like the West plant that destroyed dozens of homes when it exploded, many of these facilities are located near residential communities.

A Dow Chemical Facility in Freeport, Texas, for example, is located within a mile of the city of Oyster Creek, which has a population of about 1,100 people. The facility has reported 15 accidents in the past decade and a half. The accidents led to 19 injuries, forced the evacuation of 130 people and caused more than $11 million in property damage, according to an interactive map released this week by CEG.

In all, the 1,000 reported accidents at facilities holding large quantities of anhydrous ammonia resulted in 19 deaths, 1,651 injuries, and nearly $350 million in property damage. A total of 63,676 people in the facilities and surrounding communities and neighborhoods had to be evacuated when accidents occurred.

“We hope people will use our new interactive map to find out what’s around them and then ask their local public officials if they’ve seen risk management plans and related reports for their areas,” said Sean Moulton, a policy director at CEG. “We all need to make sure our communities and emergency service providers are prepared.”

Tougher Regulations?

Last year, the National Environmental Justice Advisory Council (NEJAC), a federal advisory group to the EPA, wrote a letter to former EPA administrator Lisa Jackson asking the EPA to address “specific threats” to communities near chemical facilities by toughening security and storage standards and asking facilities to use less toxic chemical alternatives.

Truthout asked the EPA if any progress had been made with regard to this request from NEJAC, but a spokesperson for the agency did not issue a response by the time this article was published.

According to a Congressional Research Memo prepared for Sen. Frank Lautenberg (D-New Jersey), there are 6,985 chemical facilities across the country that fall under federal monitoring criteria because, under a “worst-case scenario,” an accident at these facilities could impact populations of 1,000 people or more. Accidents at 90 of the facilities on the list would put populations of over 1 million in danger.

On April 10, Lautenberg reintroduced the Safe Chemicals Act, which would reform federal regulations and bolster EPA chemical safety programs. Lautenberg has been pushing for reforms to federal chemical safety regulations since 2005.