title: Biocidal activity of formaldehyde and nonformaldehyde biocides toward Mycobacterium immunogenum and Pseudomonas fluorescens in pure and mixed suspensions in synthetic metalworking fluid and saline.
abstract: The microbicidal activity of four different biocides was studied in synthetic metalworking fluid (MWF) against Mycobacterium immunogenum, a suspected causative agent for hypersensitivity pneumonitis, and Pseudomonas fluorescens, a representative for the predominant gram-negative bacterial contaminants of MWF. The results indicated that M. immunogenum is more resistant than P. fluorescens to the tested formaldehyde-releasing biocides (Grotan and Bioban), isothiazolone (Kathon), and phenolic biocide (Preventol). Kathon was effective against mycobacteria at lower concentrations than the other three test biocides in MWF. In general, there was a marked increase in biocidal resistance of both the test organisms when present in MWF matrix compared to saline. Increased resistance of the two test organisms to biocides was observed when they were in a mixed suspension (1:1 ratio). The results indicate the protective effect of the MWF matrix against the action of commonly used biocides on the MWF-colonizing microbial species of occupational health significance, including mycobacteria.
authors.affiliation: Molecular Toxicology Division, Department of Environmental Health, University of Cincinnati Medical Center, Cincinnati, OH 45267-0056, USA.
authors.forename: Suresh B
authors.initials: SB
authors.lastname: Selvaraju
authors.forename: Izhar U H
authors.initials: IU
authors.lastname: Khan
authors.forename: Jagjit S
authors.initials: JS
authors.lastname: Yadav
mesh_terms: D000542:Alveolitis, Extrinsic Allergic / Q000382:microbiology; D001593:Benzyl Compounds / Q000494:pharmacology; D004202:Disinfectants / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D004866:Equipment Contamination; D005557:Formaldehyde / Q000494:pharmacology*; D006801:Humans; D007219:Industrial Oils / Q000382:microbiology; D008669:Metallurgy; D008826:Microbial Sensitivity Tests; D009161:Mycobacterium / Q000187:drug effects*; D011551:Pseudomonas fluorescens / Q000187:drug effects*; D013844:Thiazoles / Q000494:pharmacology
chemical_list: D001593:Benzyl Compounds; D004202:Disinfectants; D013844:Thiazoles; D005557:Formaldehyde; C041975:Preventol D2; C037057:Kathon 886