Salud Pública de México
Print version ISSN 0036-3634
ACOSTA-GIO, Enrique; HERRERO-FARIAS, Aurelio and MATA-PORTUGUEZ, Víctor Hugo. Benzalkonium chloride is unacceptable to sterilize or disinfect medical or dental instruments. Salud pública Méx [online]. 2001, vol.43, n.6, pp. 570-573. ISSN 0036-3634. http://dx.doi.org/10.1590/S0036-36342001000600008.
Objective. To compare the sporicidal activity of benzalkonium chloride (BKC) with that of glutaraldehyde. Material and Methods. A comparative study was conducted at the microbiology laboratory of Facultad de Odontología, Universidad Nacional Autónoma de México. Bacillus subtilis ATCC 9372 spores were exposed to these germicides (1 spore x mL) on a 0.22 mm filter. After completing the contact time the spores were washed and the filters were incubated on nutrient agar for 72 h at 37ºC. Results. BKC did not eliminate B. subtilis spores at the concentration used, not even after increasing contact time to 15 h (900-fold the recommended time). Two percent glutaraldehyde destroyed spores only after 10 h of contact. Urea and sodium chloride showed no sporicidal activity. Conclusions. The results confirm that BKC lacks sporicidal activity and confirm that this quaternary ammonium compound is not able to "sterilize" or "disinfect" medical and dental instruments. The English version of this paper is available at: http://www.insp.mx/salud/index.html
Keywords : benzalkonium compounds; sterilization; disinfectants; sporicide; germicide; Mexico.