[Histonet] 5% Chromic acid disposal

[Bob Richmond]

Sharon at Celligent Diagnostics in Spartanburg SC asks:

>>We are changing our GMS stain over from a Periodic acid kit to a 5%
chromic acid kit. What do the labs that use chromic acid in special
staining do with the waste/ used chromic acid?<<

I hope someone can give an authoritative answer to this question, with
references. Chromic acid (chromium trioxide, CrO3) is a strong oxidant, and
chromium is toxic and an environmental hazard. I'd be comfortable with
pouring it down the drain with a LOT of water, but what do the authorities
want us to do?

Bob Richmond
Samurai Pathologist
Maryville TN