If you had been among Freedom Industries’ dozens of employees, you would have known more than your neighbors about the contents of a toxic spill that left hundreds of thousands of West Virginians without safe tap water recently.

After state officials discovered on Jan. 9 that chemicals had gushed out of a storage drum and into Elk River, the company told them that the drum contained something called 4-Methylcyclohexane methanol. The poison is used by the state’s coal miners. Little is known about the precise hazards that it poses, but it has sickened hundreds of people.

What the company didn’t tell the government until last week was that the drum also contained something that they call stripped PPH. The company did, however, tell its own workers about that second chemical in an email immediately after the spill. So, lucky them.

Stripped PPH was mixed in with the other chemicals in the drum at a concentration of about 6 percent. A material safety data sheet (MSDS) provided to state officials says stripped PPH contains a complex mixture of polyglycol ethers. “The specific chemical identity is being withheld as ‘trade secret,'” the company wrote in the safety document, which was dated Oct. 15, 2013.

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According to the MSDS, stripped PPH causes skin irritation and “serious” eye irritation. Workers are warned to wear protective gloves, goggles, and face protection whenever they work with it. And in case of a chemical spill? “Persons not wearing protective equipment should be excluded from the area of the spill until cleanup has been completed.”

So nice of them to let us know. Here’s more from the AP:

The company at the center of the West Virginia water crisis immediately knew a second chemical leaked from its plant into the Elk River, and told its workers in an email, according to a state environmental official.

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However, Freedom Industries did not let state government officials know about the second chemical until days after the spill. And state environmental department official Mike Dorsey said most company employees did not skim far enough into the email to see that information. …

“The explanation I was given was that they had the information on the very first day,” said Dorsey, chief of the state environmental agency’s homeland security and emergency response division.

After learning of the presence of the second chemical, state officials tested for it, but found no traces of it.

Meanwhile, more than 500 people have now been hospitalized with ailments linked to the spill. And the company is enjoying newfound bankruptcy protection from lawsuits.