A comparison of thiomersal and 50% alcohol as preservatives in urinary cytology.

The efficacy of 50% ethyl alcohol and of thiomersal as preservatives in urinary cytology were compared. In both methods over 80% of the cells were sufficiently well preserved after three days to allow cytomorphological evaluation, and over 50% on the seventh day. In the specimens without preservative, only 54% and 28% were intact after the same time intervals. In contrast with 50% ethyl alchohol, thiomersal is a more effective bactericide, it does not increase the volume of the sample, it is cheaper, and it does not affect the cytomorphology.