Glyoxal: a proposed substitute for formalin in H&E and special stains.

Neutral-buffered formalin (NBF) has been used as the primary fixative in anatomic pathology laboratories for decades. Although it yields excellent morphologic and staining results, NBF poses significant health hazards requiring tissue to be grossed under a grossing/chemical fume hood. Glyoxal fixatives offer far less toxic alternatives and do not necessitate use of a grossing hood. Using freshly extracted canine and feline testes, ovaries, and uteri, the effects of glyoxal and NBF fixation were compared. While NBF is still considered the gold standard, some glyoxal fixatives perform as well as NBF in regards to morphology, H&E staining properties, and histochemical staining properties.