Characterization and concentration of airborne fungi in public transport vehicles in Istanbul

Abstract

The study investigated the concentration and distribution features of culturable airborne fungi (CAF) in indoor air for four public transport vehicles (bus, metro, metrobus, and ferry) in Istanbul. The collection of indoor air samples was performed from each transport vehicle in both directions once a month from March 2017 to February 2018. The highest and lowest CAF concentrations measured during the study were determined to be 40–660 CFU/m3 in bus, 20–400 CFU/m3 in metro, 40–360 CFU/m3 in metrobus, and 20–260 CFU/m3 in ferry. It was determined that no fungal colonies were observed on the ferry on the inbound route in March. The findings demonstrated that CAF concentrations in bus were higher compared to the indoor air in other transport vehicles, and there was a significant correlation between fungal levels and the number of passengers (p < 0.05; r = 0.68) and RH% (p < 0.05; r = 0.43). In line with the density order of fourteen fungal species determined, Penicillium spp., Paecilomyces spp., and Aspergillus spp. were identified. The results of this study also showed that there were high levels of fungi in public transport vehicles that could affect human health in many sampling periods. Many countries are trying to or have established their national ambient air quality standards, following the WHO Air Quality Guidelines. Unfortunately, Turkey does not have official standards for indoor air quality (IAQ). Therefore, monitor, control, and maintenance of IAQ-related research in such public transport vehicles in Turkey are necessary as much as development of standards related to it.