title: Triazole Susceptibilities in Thermotolerant Fungal Isolates from Outdoor Air in the Seoul Capital Area in South Korea.
abstract: Emerging fungi resistant to triazoles are a concern because of the increased use of medical triazoles and exposure to agricultural triazoles. However, little is known about the levels of triazole susceptibility in outdoor airborne fungi making it difficult to assess the risks of inhalation exposure to airborne, antifungal-resistant fungi. This study examined triazole susceptibilities of the airborne thermotolerant fungi isolated from the ambient air of the Seoul Capital Area of South Korea. We used impactor air sampling with triazole-containing nutrient agar plates as the collection substrates to screen for airborne fungal isolates based on their triazole susceptibilities. This study estimated that 0.17% of all the culturable fungi belong to the pathogenic thermotolerant taxa, among which each isolate of Aspergillus niger and Aspergillus tubingensis showed a minimum inhibitory concentration (MIC) of 2 μg/mL or greater for itraconazole. Their concentration in air was 0.4 CFU/m3. Seven human pathogenic Paecilomyces variotii isolates had MICs of 32 μg/mL or greater and lower than 2 μg/mL for the agricultural fungicide tebuconazole and the medical triazole itraconazole, respectively. Though the concentration was low, our results confirm the presence of airborne fungi with high MICs for itraconazole in ambient air. Inhalation is an important exposure route because people inhale more than 10 m3 of air each day. Vigilance is preferred over monitoring for the emergence of triazole-resistant fungal pathogens in ambient outdoor air.
authors.affiliation: Department of Environmental Health Sciences, Graduate School, of Public Health, Seoul National University, Seoul 151-742, South Korea.
authors.forename: Seungeun
authors.initials: S
authors.lastname: Lee
authors.affiliation: Department of Environmental Health Sciences, Graduate School, of Public Health, Seoul National University, Seoul 151-742, South Korea.
authors.forename: Siyu
authors.initials: S
authors.lastname: Xu
authors.affiliation: Department of Environmental Health Sciences, Graduate School, of Public Health, Seoul National University, Seoul 151-742, South Korea.
authors.forename: Chemmeri Padasseri
authors.initials: CP
authors.lastname: Bivila
authors.affiliation: Department of Environmental Health Sciences, Graduate School, of Public Health, Seoul National University, Seoul 151-742, South Korea.
authors.forename: Hyeyoung
authors.initials: H
authors.lastname: Lee
authors.affiliation: School of Biological Sciences, College of Natural Sciences, Seoul National University, Seoul 151-742, South Korea.
authors.forename: Myung Soo
authors.initials: MS
authors.lastname: Park
authors.affiliation: School of Biological Sciences, College of Natural Sciences, Seoul National University, Seoul 151-742, South Korea.
authors.forename: Young Woon
authors.initials: YW
authors.lastname: Lim
authors.affiliation: Department of Environmental Health Sciences, Graduate School, of Public Health, Seoul National University, Seoul 151-742, South Korea.
authors.forename: Naomichi
authors.initials: N
authors.lastname: Yamamoto
mesh_terms: D000391:Air Microbiology; D000935:Antifungal Agents / Q000494:pharmacology*; D001230:Aspergillus / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D004271:DNA, Fungal / Q000032:analysis; D025141:Drug Resistance, Fungal; D017964:Itraconazole / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D003904:Mitosporic Fungi / Q000145:classification* / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D010143:Paecilomyces / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D056910:Republic of Korea; D017422:Sequence Analysis, DNA; D014230:Triazoles / Q000494:pharmacology*
chemical_list: D000935:Antifungal Agents; D004271:DNA, Fungal; D014230:Triazoles; D017964:Itraconazole; C087114:tebuconazole