1. Are you currently using B5 fixative?  No

2. Has your lab used B5 fixative in the past? In clinical laboratories, yes.

3. If you have discontinued it's use, when and why? We discontinued it once
Zinc Formalin came out.  We used to fix lymph nodes in it, and fixed our
bone marrows in Zenker's. We discontinued it due to our concern for waste
disposal of the mercury.  We followed the information given in Hazardous
Material in the Histopathology Laboratory manual to precipitate the mercury
out and filter the solution.

4. What alternative fixative are you using in it's
place?  Zinc Formalin

5. Do you need to use the "de-zenk" procedure for this
substitute?  No, as it contains no mercury.

6. If you use B5; and work in a reference lab, what
percentage of cases require it's use?  We used ZnFormalin instead,
post-fixing GI biopsies.  We used AZF fixative (Acetic Acid-Zinc Formalin
from Newcomer Supply) for primary fixation of our bone marrow specimens.


Teri Johnson
Manager Histology Core Facility
Stowers Institute for Medical Research
1000 E. 50th St.
Kansas City, Missouri  64110
tjj@stowers-institute.org