Let me give my thanks to everybody who has taken the time to critique my original posting. I even got an ‘off-line’ (tongue in cheek?) reply reminding me that I had been ridiculously over-inclusive by my use of the word “all” volatiles…OK, most aqueous mixtures are innocuous—unless you happen to fall asleep and drown in them. (Thanks, Doc). If I might ask for the indulgence of a follow-up to the original posting, I would like to re-state the case and also correct the spelling error of “REL” (too much ethanol exposure, perhaps).

Smelling a chemical is a trailing indicator. A safe, healthful lab needs procedures in place to reduce or eliminate exposure to most (I said “most”, Doc) volatile reagents. There is no one procedure that can address all exposure situations. The chemists need to be trained to recognize that many reagents have poor warning properties, have undetectable properties and can have adverse health effects with repeated exposure at sub-detectable or sub-regulated levels.

This topic was eating on me for the better part of the day, today and I continued to return to the analogy of exposure to ionizing radiation: No human can sense the exposure but no human can escape the deleterious effect of exposure. Radiation sickness is the trailing indicator. Safeguards need to be established to safely handle those materials. That’s where you establish safe handling techniques, engineering controls, perform sampling and monitoring and conduct appropriate training. Radioactive isotopes are regularly handled and the safety record is fairly good. Why should chemical handling be any different?

And, just for the record, our chemists routinely handle aqueous mixtures of various active pharmaceutical actives. Among those are female hormonal agents, which, as you can imagine have incredibly low OELs. You can bet that they (especially the males) are scrupulous in the usage of PPE, fume hoods and VBEs and they avoid any practice that would cause those mixtures to become airborne even when they are handling aqueous solutions/suspensions. So far, we have had no over-exposure symptoms among our people.

I hope that Sammye has had her question answered.

James S. Bonnell

Manager, Environmental Services

Duramed Pharmaceuticals, Inc., subsid. Teva Pharmaceuticals, Inc.

Cincinnati