Aims - The effects of alcohol based fixation and microwave stimulated
alcohol fixation were investigated on spores of Bacillus stearothermop
hilus and Bacillus subtilis (var. niger). Methods - Spores were expose
d to 10% formalin, or different concentrations of various alcohol cont
aining (Kryofix/Spuitfix). Adequate were also set up in conjunction wi
th the test solutions. The spores were immersed with and without adjun
ctive microwave stimulation in the various solutions tested. Possible
surviving spores were recovered in revival broth and after incubation,
and Gram staining viable counts were performed. Results - Alcohol bas
ed fixatives did not have a sporicidal effect on B stearothermophilus
or B subtilis (var. niger) spores, and microwave stimulated alcohol fi
xation at 450 W and up to 75 degrees C did not have a sporicidal effec
t. Conclusions - When alcohol based fixatives are used for fixation, p
recautions should be taken with the material thus treated, as it may c
ontain viable spores or other pathogens, which are destroyed after 24
hours of formalin treatment. Of the physicochemical methods tested inv
olving microwaving, none was successful in eliminating viable spores f
rom the test material.