A  Houston, TX DuPont chemical plant is under investigation after four workers died Saturday due to a chemical leak and a fifth worker was hospitalized and later released.

Around 4 a.m. Saturday a poisonous gas called methyl mercaptan began to leak.

Around 7 a.m. workers dressed in PPE protective gear entered the plant responding to a valve leak, they found the workers unresponsive.  Around noon the plant was deemed safe again but not before the medical examiner confirmed the four deaths.

The federal Chemical safety Board sent a team to Texas to find the cause of the leak and figure out how is killed as many people as it did.  This is a high number of deaths for this gas when it did not involve a fire or and explosion of it.

The leak was contained to just the facility and posed no threat to any surround public areas.

There are not many fatal accidents noted involving methyl mercaptan.  The gas has a terrible smell of rotten eggs and is used in products from pesticides to jet fuel.  It has also been know to be added to odorless methane to alert workers if there is a leak.

This is an interested story because with a gas like this that has such an obnoxious smell to it you would think someone would have smelled it to alert the others of a leak?  Was it so massive and fierce that it just knocked everyone out and killed them? I will be curious to see what the federal Chemical agency concludes in their investigation.