(CBS/AP)-- A New Jersey bridge collapse and derailment of four Conrail freight tank cars is being blamed on an old-style swing rail bridge that had previously buckled and been rebuilt.
The train derailment that occurred around 7 a.m. on Friday in Paulsboro sent at least two cars into Mantua Creek and caused a leak of a hazardous gas known as vinyl chloride that is used to make plastics.
More than a dozen people reported breathing problems after the accident. Eleven people were transported to Underwood-Memorial Hospital, and five more arrived on their own, CBS station WCBS in New York reported. Paulsboro, East Greenwich, and West Deptford residents were told to stay in their homes after the accident.
Inhaling vinyl chloride can cause eye and respiratory tract irritation, according to the Environmental Protection Agency. At high levels, it can cause loss of consciousness, lung and kidney irritation, prevention of blood clotting in humans, cardiac arrhythmias in animals and other effects on the central nervous system, including dizziness, sleepiness and giddiness.
Vinyl chloride has also been shown to increase the risk of a rare form of liver cancer and, in a few studies, to affect male sexual performance.
Assemblyman John Burzichelli, who is serving as spokesman for the town, says the rail bridge apparently buckled, just as it did during a derailment in 2009. The bridge was rebuilt in 2010.
State environmental officials say only one of the cars leaked any gas. It was carrying vinyl chloride and all of it has since dissipated into the air. At high levels of exposure it can cause breathing problems, dizziness and nausea.
The National Transportation Safety Board is sent investigators to the scene Friday morning.