The Texas plant that was the scene of a deadly explosion this week was last inspected by the Occupational Safety and Health Administration in 1985.

As of last night, one person was confirmed as dead in the explosion at the West Fertilizer Co plant, 35 were missing and 160 injured, making it potentially one of the worst US industrial disasters in years.

But Mayor of West Tommy Muska had said yesterday the death toll had reached 14 people.

Among them were four emergency medical technicians killed in the blast, which occurred on Wednesday evening after emergency responders rushed to put out a fire at the plant.

Five volunteer firefighters are officially listed as missing but feared dead, Mr Muska said. Earlier yesterday, officials put the death toll at between 5 and 15.

The risk plan the plant operators had filed with regulators listed no flammable chemicals, it has emerged. I had been cleared to hold many times the ammonium nitrate that was used in the Oklahoma City bombing.

For worker- and chemical-safety advocates who have been pushing the US government to crack down on facilities that make or store large quantities of hazardous chemicals, the blast in West, Texas, was a grim reminder of the risks these plants pose.

They say regulators haven't done enough to tackle the problem. "Definitely, somewhere along the line at the federal level, there was a failure," Sean Moulton, director of open government policy at the Center for Effective Government, a Washington-based watchdog, said in an interview. "It was quite clear that they just didn't consider flammability or explosiveness to be a problem, and given what occurred that was clearly shortsighted."

The fire and explosion at Adair Grain Inc's West Fertilizer Co plant flattened houses and devastated the centre of the town of West, about 80 miles south of Dallas.

Agricultural Chemical West Fertilizer produced anhydrous ammonia, a combination of nitrogen and hydrogen that farmers inject into the soil as a crop nutrient.

It also held in storage as much as 270 tons of ammonium nitrate, a solid fertiliser that was used by Timothy McVeigh to destroy the Alfred P Murrah Federal Building, killing 168 people, in Oklahoma City 18 years ago today.

This material was also employed by the IRA in its 1996 Canary Wharf attack in London.

There are no federal rules mandating that such plants be located away from residential areas, and the current company safety plans aren't always shared widely with residents nearby, said Paul Orum, an independent consultant who has authored reports on chemical safety for the Center for American Progress. In Texas, "I would be surprised if the risks present were communicated to those nearby," he said in an interview.

The Texas Secretary of State's office lists Donald R Adair and Wanda L Adair as owners and co-directors of Adair Grain, with Donald serving as president and Wanda as vice president.

A man who answered a reporter's telephone call to the company declined to identify himself or comment.

The company has been cited for a series of violations over the past few years.

Reuters/Bloomberg