B-5 and other mercuric fixatives essentially cannot be used without releasing significant amounts of mercury to the sewer system. Most or all of the fluids on the tissue processor are contaminated with mercury after B-5 specimens are run through. Now there is a replacement for these fixatives that acts like B-5 and produces results indistinguishable from B-5, without the drawbacks. Z-5 will not harden tissue even when fixation time is hours or days long. It penetrates and fixes as fast as B-5. There are no crystals to remove from sections. Immunoreactivity is preserved with most antigens, reducing the need for antigen recovery operations. And the cost is substantially below that of B-5.

Z-5 Fixative

Concentrate to make 820 ml of fixative. Just add alcohol to the partially filled bottle. Diluted solution is stable for at least 1 year.