CLEVELAND -- Hazardous materials pass through Northeast Ohio neighborhoods each day by train, and first responders tell Channel 3 they need better notification of what potentially dangerous chemicals are board.

In May, a CSX train derailed in Rosedale Maryland after colliding with a garbage truck. The derailment caused a fire, and an explosion powerful enough to damage buildings blocks away.

Among the chemicals on board the train, sodium chlorate, which can be used to make, among other things, herbicides and explosives. The Rosedale derailment is proof of what makes emergency responders so nervous.

"What really concerns us the most is what is on the train," says Painesville Fire Chief Mark Mlachak, who tells Channel 3 first responders are effectively in the dark about what is on board a train until after it derails.

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"We knew we had a threat, and we evacuated to the half mile. We didn't actually know what was burning," Mlachak says in recalling the 2007 train derailment in Painesville.

Most of the hazardous materials on board, such as ethanol were discovered early because of placards displayed on rail cars.

But to figure out the rest, Mlachak says it took combing through pages of the train's manifest and comparing codes with rail cars.

"We didn't know about the phthalic anhydride for quite a while. That could have been a deal breaker. There is no quick easy way to find out what is in that fire. You have to recon. You have to do research," Mlachak says of the derailed car that proved to be most challenging to identify.

Phthalic anhydride is a chemical used in making plastics. It can cause burning if inhaled and skin irritations. "

," Mlachak adds.

According to the Federal Railroad Administration, no federal law requires public disclosure of hazardous materials being carried by trains. However, local governments can request railroads provide a list of their top 25 hazardous materials to local government officials upon request.

That information can be shared with responders for planning and training. Emergency responders that Channel 3 spoke to say railroads have been proactive in helping them with emergency preparedness drills.

In Painesville, 1,400 residents were evacuated safely, and crews were able to contain the spill, and limit the environmental impact.

But what if a similar derailment happened just a few miles away in downtown Cleveland?

"Several hundred-thousand people downtown at any given time on a work day? And if there was going to be a spill? There could be potential catastrophic effects," says Cleveland Councilman Matt Zone.

He and other leaders have pushed for rerouting hazardous loads around Cleveland. In fact, 6 years ago he showed us a proposed reroute that would utilize existing track and reduce the population exposure by one-third.

But the plan stalled.

"The most appropriate level of government to work with the rail lines to look at how they are routing their trains is the federal government," Zone says.

Several years ago, the Department of Homeland Security deemed Cleveland a "high threat urban area," meaning it's more susceptible to attack by terrorists targeting railroad tank cars.

"What if someone wanted to sabotage these trains, particularly when they are transporting hazardous chemicals, sometimes spent nuclear fuel," Zone asks, voicing his concern.

Shel Lustig is a retired railroad industry veteran, who now shares his knowledge with Cuyahoga County's Local Emergency Planning Committee.

In 2004, Lustig helped create a derailment scenario along Cleveland's lakefront. A freight train carrying hazardous materials derails behind Cleveland's FBI building. The scenario included a fire and explosion. The conditions were a warm summer workday afternoon with a north wind coming off the lake.

"Are we equipped to handle it? Then, the answer was no. And while some improvements have been made, I'm sure the answer today would also be no," Lustig says.

For their part, railroads are under a "common carrier obligation" as part of the Interstate Commerce Act. Railroads are mandated to carry all goods offered for transportation, including hazardous shipments. The Federal Railroad Administration says railroads have expressed concern over this obligation, as it relates to safety and enormous liability.

We did reach out to CSX and Norfolk Southern, two of the railroads that transport through Northeast Ohio. Norfolk Southern is looking into whether they've received proposals to reroute train traffic and promised to follow up with us.