Journal of Hygiene

Research Article

The sterilizing capacity of propylene oxide and chlorhexidine diacetate solutions upon pre-injection swabs saturated with propan-2-ol

R. C. Wrighta1 p1

a1 Everett Medical Products Ltd, 2–10 Commonside East, Mitcham, Surrey


The sporicidal activity of two solutions which have been used in the production of ‘sterile’ pre-injection swabs has been investigated. Propylene oxide (3·4 % w/w) and chlorhexidine diacetate (0·6% w/w), both made up in approximately 65% w/w propan-2-ol, were artificially contaminated with spores of Bacillus subtilis var. niger and swabs were impregnated with these; surviving spores were enumerated at various temperatures and times of storage. Chlorhexidine diacetate had no sporicidal activity, whereas the activity of propylene oxide was dependent on temperature. The former should not be considered a sterilant and the latter can only be considered such if a controlled incubation period at an elevated temperature is employed.

(Received February 07 1983)

(Accepted May 23 1983)


p1 Present address: Analytical Laboratory, Njala University College, P.M.B., Freetown, Sierra Leone