"The family is understandably devastated and intends to pursue this matter to the fullest extent of the law," according to the attorney representing the family.
One person is dead and 23 others are injured after a train accident Monday morning.
Authorities confirmed the leak was styrene, a flammable liquid used to make plastics and rubber, according to the National Institute of Environmental Health Sciences.
Funding to improve safety at a Burlingame railroad crossing was cut from California's budget and now leaders are pleading for it to be restored.
The operator of the oncoming train saw the teen fall and pulled the emergency brakes, but was unable to stop in time, authorities said.