Following last April’s deadly explosion of ammonium nitrate at the West Fertilizer Co. in West, Texas, reporters from The Associated Press have found that 120 facilities housing or processing hazardous materials are located within a “potentially devastating blast zone of schoolchildren, the elderly and the sick.”

However, those records were only available for 28 states – more than a half-dozen others, including Ohio, Connecticut, Hawaii, Idaho and South Carolina, refused to provide the information, citing the risk of terrorist attacks and their interpretations of federal law.

Sixty of those facilities report to state regulators has having as much or more ammonium nitrate than the 540,000 pounds West Fertilizer reported having last year.

Because of the material’s explosive potential, AP reports, if a fire were to break out at an ammonium nitrate company, everyone within a quarter- to a half-mile radius could be as risk. Debris from the West, Texas, explosion landed more than two miles away. And, more often than not, AP says, “the danger zones are middle-class or poor neighborhoods.”

Information on the hazardous materials storage must be requested from state environment agencies or emergency management services, as well as county emergency management officials. The federal government does not keep a central database, and the Homeland Security Department does not share its list due to security concerns.