Characterization and health risk assessment of size-segregated fungal bioaerosols in and around a sugar mill in India

Suspended particles of biological origin comprising of virus, fragments of plants and animals dander, pollen grains, fungal spores and bacteria known as bioaerosols have become a major concern in the past decades. In the present study reports, the concentration and size distribution of fungal bioaerosol in and around a sugar mill situated in the Muzaffarnagar region of Uttar Pradesh, India, are presented. The sampling was performed in the winter when the mill used to be in the operational mode. The highest mean fungal concentration was observed at the cutter site (4022 ± 321 cfu/m³) and lowest at storage site (832 ± 85 cfu/m³). The maximum and minimum concentration of fungal bioaerosol was observed during January (3090 ± 174 cfu/m³⁾ and March (629 ± 69 cfu/m³) respectively. During the entire sampling period, the fine fraction of fungal bioaerosol was observed to be significantly higher at all the sites, whereas coarse fraction was lower. The association between fine and coarse fractions of bioaerosols showed a very strong positive relationship. The levels of fungal bioaerosol and their association with the meteorological parameters in sugar mill were also conducted. A positive association with the relative humidity and wind speed was observed at significance level of p < 0.05, whereas a negative relation was observed with temperature at p < 0.05. The lifetime average daily dose was calculated for both inhalation and dermal; among them LADD_inhalation is ~ 5 times over LADD_dermal. The health risk index was observed as < 1 for both inhalation and dermal routes, whereas HI_inhalation value was 10⁵ times higher than the HI_dermal value. The dominant fungi genera found in the air of examined dwellings were Penicillium spp., Aspergillus spp., Cladosporium spp., and Alternaria spp., which occurred predominantly at all of the studied sites during the sampling period.