A fluorescence bioassay to detect residual formaldehyde from clinical materials sterilized with low-temperature steam and formaldehyde.
A microtiter plate toxicity test based on fluorescence was developed to determine the residual concentration of formaldehyde on medical items after LTSF sterilization. The residual formaldehyde on eight common materials, some of which are used in different clinical instruments and devices were analysed after sterilization with LTSF. Formaldehyde residues were detected on cotton, filter paper, natural rubber, PVC, and silicone-coated latex, but not on polyurethane, silicone or glass. Formaldehyde never exceeded the recommended maximum concentration on clinical devices of about 5 microg/cm2. The results were compared with those obtained by means of a chemical method, the correlation being good (R2=0.9396). The biological method proposed here is fast and can be automated, which means that it could be used as a screening method when there are doubts as to the accumulation of residues on clinical materials or instruments that are going to be sterilized with LTSF.
Mariscal
Alberto
A
Department of Preventive Medicine and Public Health, Faculty of Medicine, University of Malaga, Avda. L. Pasteur, Campus de Teatinos, E-29071 Malaga, Spain. mariscal@uma.es
Carnero-Varo
Manuel
M
Gomez
Enrique
E
Fernandez-Crehuet
Joaquin
J
D001681:Biological Assay / Q000379:methods*; D005453:Fluorescence; D005557:Formaldehyde / Q000032:analysis*; D013227:Steam; D013242:Sterilization; D013696:Temperature; D018675:Toxicity Tests
D013227:Steam; D005557:Formaldehyde