Hazard warnings for acute and chronic chemical hazards

September 4, 1985

Mr. Thomas S. Allen
Product Label Specialist
Ethyl Corporation
[Recipient address omitted]
Dear Tom:

Thank you for your letter of June 13, 1985, regarding questions you have concerning interpretations of the Hazard Communication Standard. The responses are as follows.

In your first question, you asked whether a material safety data sheet (MSDS) and/or label for your antiknock compound should reflect the chronic hazards of EDB or EDC when the acute hazard of tetraethyl lead is so severe. The MSDS for a compound must reflect all valid evidence concerning both the acute and chronic hazards of the constituents. Your company is free to make whatever statements seem appropriate regarding the relative hazards based upon the composition, but the evidence must be reported. That is the essence of a "right-to-know" standard.

On the label, the standard required "appropriate hazard warnings." There is obviously a need for professional judgment to determine what is "appropriate" in each situation. However, in areas where a judgment must be made, it would be prudent to err on the side of disclosure. This approach is consistent with the intent of the standard. Given the high percentage of both EDB and EDC present in your compound, my personal opinion is that the chronic hazards should certainly be on the label as well as on the MSDS.

With regard to question no. 2, I think it would be reasonable to assume that if a component that is corrosive by itself is not shown to be so when tested in a mixture where it comprises 25% of the compound, it would also not render the mixture corrosive when it comprises 1-5%. Of course, that assumption is also based upon the diluent being the same, and not something which could produce a synergistic effect. When you state that the label would only cover the acute hazards of the mixture, I assume that you mean there are no chronic hazards associated with the mixture. I am also assuming that corrosivity is the only health hazard ZDDP contributes to the mixture.

The answer to question no. 3 is related to no. 1. Again, the MSDS is a compilation of everything known about a chemical, whereas some degree of judgment is required to determine what is "appropriate" to put on a label. Certainly, the IARC information must be on the MSDS. And unless there is a scientifically defensible reason not to, I would indicate the cancer hazard on the label as well.

I hope this information is helpful to you. If we can be of further assistance to you, please do not hesitate to contact us.

Sincerely,

Jennifer C. Silk
Health Scientist
Health Standards Programs

[Requester letter reproduced on OSHA page; omitted here.]