SAN ANTONIO -

A deadly train accident in Canada is raising serious concerns about the safety of transporting oil by rail here in Texas.

On July 6, 2013 an unattended train hauling crude oil rolled down a hill into the small town of Lac-Mégantic, Quebec. The tanker cars, filled with crude oil from a shale field in North Dakota, derailed and ignited an explosive fireball that leveled dozens of buildings and left 47 people dead.

In the wake of the tragedy a handful of other trains hauling crude oil have also derailed, caught fire and exploded here in the U.S.

The accidents have raised serious questions about the safety of moving oil by rail and the volatility of that oil.

"The alarm bells are ringing in other states and before there's a big fire here in Texas we need to make sure we get some better standards in place," warned Tom "Smitty" Smith, Director, Public Citizen Texas.

An energy industry watchdog, Smith is worried about a dramatic increase in trains transporting oil across the country and here in Texas.

"Nationally it's up 400 percent over the past five years and as we're beginning to see it can have potentially explosive problems," Smith said. "Part of the problem that we've seen with this dramatic increase in the use of rail to haul crude is a significant increase in the amount of spills. It's gone from about 800 thousand to 1.5 million barrels in just the last year."

The increase in trains hauling crude oil is a direct result of the shale oil boom happening in the U.S. Much of that train traffic is coming from the Bakken Shale formation located in North Dakota. There's not enough pipeline to transport the oil to market so oil companies have been forced to rely on rail instead, turning the rails into mobile pipelines.

"They simply can't keep up building enough pipelines to get the product to the markets," Smith said.

It's a different story in Texas where there's already an existing pipeline infrastructure in place but the production in the Eagle Ford is outpacing the building of additional pipelines.

"Pipeline is the most desirable way to get it to market but the pipeline infrastructure is only recently beginning to react to the new finds," said Thomas Tunstall Research Director, UTSA Institute of Economic Development. "In the Eagle Ford Shale in particular but also in West Texas they're starting to build out some pipeline infrastructure as well."

Because of the existing pipeline infrastructure, Texas is far less reliant on rail to get the oil to market.

"I haven't really seen anything to really indicate if there's any heightened risk here in South Texas as a result of rail transport," Tunstall said. "We know that some oil is being transported by rail but in the case of South Texas, because there is so much pipeline infrastructure in place, I imagine a lot less rail transport occurs here to take crude out, or oil and condensate, than other parts of the country."

According to the Texas Railroad Commission there has been an increase in oil moved by rail in recent years. The commission reported "362,732 barrels of oil and condensate were moved off-lease by rail/barge in 2011; and 401,700 barrels of oil and condensate were moved off-lease by rail/barge in 2012."

Ramona Nye, a spokeswoman for the commission, stated in an email the staff's best estimate is that "about 90 percent to 95 percent of those figures represent rail transport."

Tom Smith isn't just worried about the increased use of rail to transport oil, there's also growing concern about the oil itself.

Tests performed on the oil that exploded in Canada revealed the shale oil was more volatile and more flammable than traditional crude oil and likely made the accident more deadly.

The findings prompted the U.S Department of Transportation's Pipeline and Hazardous Materials Safety Administration (PHMSA)  to issue a safety alert warning the Bakken shale oil may be more flammable than other types of crude. 

Last month the NTSB even went as far as saying "The NTSB is concerned that major loss of life, property damage and environmental consequences can occur when large volumes of crude oil or other flammable liquids are transported on a single train involved in an accident."

"That regulator is not known for having much of a bark," Tom Smith said. "For them to be starting to howl about this is an indication of just how dangerous this might be."

At this point it's unknown if the crude oil coming out of the Eagle Ford is just a volatile but the Federal government will soon know. The Pipeline and Hazardous Materials Safety Administration and the Federal Railroad Administration took samples from several wells in the Eagle Ford.

According to Gordon "Joe" Delcambre Jr, a Public Affairs Specialist for PHMSA, "testing of the samples included boiling point and flash point. The final report on these samples is still pending."

The testing is part of the government's program called "Operation Classification" which was launched last summer to "investigate how shippers and carriers are classifying crude oil and what actions they are taking to understand the characteristics of the material."

Researchers like Thomas Tunstall are eagerly awaiting the results of the tests on the Eagle Ford samples.

"It's really come as a surprise to a lot of people. Crude oil is typically not that volatile so I think a lot of us are curious to see what's going on here, what's causing these explosions," Tunstall said. "Because whatever it is, it appears to be anomalous at least to our prior experience transporting crude oil."