A New Jersey Bridge collapse has reportedly sent three train cars into the Mantua Creek and 11 people to the hospital.

According to a local Fox News affiliate in New Jersey, the U.S. Coast Guard is on the scene of the train derailment where highly toxic vinyl chloride is reported to be leaking.

The Agency for Toxic Substances and Disease Registry (ATSDR), a federal public health agency of the U.S. Dept. of Health, previously published this public health statement on vinyl chloride, which is a highly toxic and flammable substance.

That document says vinyl chloride, at room temperature, is a colorless gas that burns easily, and it is not stable at high temperatures. It exists in liquid form if kept under high pressure or at low temperatures.

Vinyl chloride has a mild, sweet odor, which may become noticeable at some levels in the air. However, the odor is of little value in preventing excess exposure.

It's a manufactured substance that does not occur naturally.

Most of the vinyl chloride produced in the U.S. winds up in polyvinyl chloride (PVC), which is used to make a variety of plastic products including pipes, wire and cable coatings, and packaging materials. Other uses include furniture and automobile upholstery, wall coverings, housewares and automotive parts.

The ATSDR reports that, at one time, vinyl chloride was used as a coolant, as a propellant in spray cans and in some cosmetics. However, since the mid-1970s, vinyl chloride mostly has been used in the manufacture of PVC.

Underwood Memorial Hospital told Fox 29 News that 18 people are reportedly having breathing difficulties. Four are being treated at that hospital.

Check back for regular updates on this breaking news story.