[Histonet] Formula 83

[Robert Richmond]

Allison Hutton, HTL(ASCP)cm, Lead Tech Histology, Doylestown Hospital,
Doylestown, Pennsylvania asks:

>>For those of you who are using Formula 83, could you please contact me off line? We have completed our demo but still have a few questions.<<

Formula 83, offered by CBG Biotech Ltd., is a napthenic (cycloalkane)
hydrocarbon used as a xylene substitute. It differs in structure from
the aliphatic hydrocarbons such as Richard Allan's Clear-rite 3. It's
in use in a lab I'm working in at the moment.

I have two reservations about it. The first is that, unlike the
aliphatics, it has a definite odor, which could be objectionable in a
confined space.

The second reservation: Formula 83 has a flash point of only 7 degrees
Fahrenheit, lower than xylene (78 degrees) and other aliphatics, some
of which have flash points as high as 144 F. The fire hazard here is
worth considering.

Formula 83 has been discussed before on Histonet, and the posts are
worth looking up.

When purchasing a new aliphatic, there are several important
considerations. Your purchasing people need to understand that they
can't change the xylene substitute on you, just because something a
bit cheaper comes along. If you recycle, every different xylene
substitute has a different distillation routine. It's important to ask
everyone in the lab - in particular, the cytotechnologist is likely to
have very strong opinions about the solvents they use in their
ascending sequence before coverslipping.

Bob Richmond
Samurai Pathologist
Knoxville TN