Microbiota associated with airborne particulate matter (PM) is an important indicator of indoor pollution as they can be pathogenic and cause serious health threats to the exposed occupants. Present study aimed to investigate the level of culturable microbes associated with PM and their toxicological characterization in urban and rural houses of Pune city. Highest concentration of bacterial aerosols observed to be associated with PM₁₀ size fraction in urban site (2136 ± 285 CFU/m³) whereas maximum fungal concentration has been measured in rural houses (1521 ± 302 CFU/m³). Predominantly found bacterial species were Bacillus sp., S. aureus, and Pseudomonas aeruginosa and fungal species were Aspergillus sp., Cladosporium sp., and Penicillium sp. in both urban and rural residential premises. Concentration of endotoxin measured using the kinetic Limulus Amebocyte Lysate assay exhibited that the level of endotoxin in both urban and rural sites are associated with household characteristics and the activities performed in indoor as well as outdoor. Cell free DTT assay confirmed the ability of these airborne microbes to induce the production of reactive oxygen species (ROS) varying along with the types of microorganisms. On exposure of A549 cells to airborne microbes, a significant decrease in cell viability was observed in terms of both necrosis and apoptosis pathway. Elevated production of nitric oxide (NO) and proinflammatory cytokines in epithelial cells and macrophages clearly suggest the inflammatory nature of these airborne microbes. Results derived from the present study demonstrated that the indoor air of urban and rural houses of Pune is contaminated in terms of microbial load. Therefore, attention should be paid to control the factors favoring the microbial growth in order to safeguard the health of exposed inhabitants.

The individual effects of biological constituents of particulate matter (PM) such as fungal spores, on lung function in children are not well known. This study investigated the seasonal short-term effect of daily variation in Alternaria and Cladosporium fungal spores on lung function in schoolchildren.This panel study evaluated 313 schoolchildren in informal settlements of the Western Cape of South Africa, exposed to spores of two commonly encountered fungi, Alternaria and Cladosporium species. The children provided forced-expiratory volume in 1-s (FEV₁) and peak-expiratory flow (PEF) measurements thrice daily for two consecutive school-weeks in summer and winter. Daily PM₁₀ levels, from a stationary ambient air quality monitor and fungal spore levels using spore traps were measured in each study area throughout the year. The effects of Alternaria and Cladosporium spores, on lung function were analysed for lag periods up to five-days, adjusting-for PM₁₀, other pollen exposures, study area, and other host and meteorological factors. Same-day exposure-response curves were computed for both fungal species.There was more variability in Alternaria spores level with noticeable peaks in summer. There were consistent lag-effects for Alternaria on PEF compared to Cladosporium, with the largest PEF deficit observed in winter (mean deficit: 13.78 L/min, 95%CI: 24.34 to −3.23 L/min) per 10spores/m³ increase in Alternaria spores on lag day-2. Although there were no observable lag-effects for Alternaria and Cladosporium on FEV₁, same-day effects of Cladosporium spores on FEV₁ was present across both seasons. Threshold effects of Alternaria on both PEF and FEV₁ deficits were apparent at levels of 100 spores/m³, but could not be explored for Cladosporium beyond the levels observed during the study.The study provides evidence for the independent effects of daily exposure to ambient fungal spores of Alternaria and Cladosporium on lung function deficits, more especially in winter for PEF.

Open landfilling is a common practice of waste dumping in developing countries, generating a range of environmental and public health hazards. In this study, we determined the distribution, composition and exposure risk of the size-segregated fungal and bacterial bioaerosols in an open landfill site in Dehradun, India. Bioaerosol and particulate matter (PM) measurements were carried out using a six-stage viable Andersen Cascade Impactor and a Wide Range Aerosol Spectrometer, respectively. Pearson correlation analysis was used to determine the relation of bioaerosol concentration with meteorological parameters and PM. The mean concentration of fungal and bacterial aerosols was observed to be 4582.75 ± 1358.25 CFU/m3 and 3609.53 ± 1000.28 CFU/m3, respectively. The bioaerosol composition showed the predominance of potential pathogens including Aspergillus (25.42%), Penicillium (20.34%), Cladosporium (15.25%), Alternaria (13.56%); and gram-negative Bacillus (21.15%), Streptobacillus (17.31%), Coccus (13.46%). Also, an inhalation risk assessment was conducted for the age-specific predictions of bioaerosol and PM deposition in human airways using a multiple path particle dosimetry model. For bioaerosols, maximum submicron depositions in the pulmonary region were observed in adults, while for PM, in children and infants. Finally, to identify the bioaerosol exposure caused respiratory disorders, a questionnaire-based health survey was conducted among the exposed population around the landfill site. The chi-square test showed significantly higher respiratory complaints in females for cold, cough, chest pain and chest tightness than in males. This work highlights the role of bioaerosols and PM in human health disorders in occupational environments associated with waste management.

The possibility of superficial foot mycoses to spread through contaminated mosque carpets between worshipers imposes a great health burden and is never addressed in Riyadh, SA. We aimed to assess the prevalence of fungal infections, especially human dermatophytosis acquired from mosque carpets, in five different regions of Riyadh, Saudi Arabia and establish a means of contamination control. A cross-sectional study of 100 mosques in Riyadh, Saudi Arabia, was conducted, using a multistage random cluster sampling technique. The study included mosques that had an ablution area and regularly hosted five prayers a day. Sterile swabs were used for sampling, and the samples were transported to the laboratory for culture and analysis using a micro-scan system. A total of 199 (65%) samples contained several fungal species. Rhodotorula (74%), Cladosporium (47%), Bipolaris (46.6%), other yeasts (43.7%), Alternaria (40%), dematiaceous molds (34%), Curvularia (32.4%), and Candida (31%) were the most frequently isolated species. Species belonging to several other genera were also detected. This study revealed a relatively high prevalence of fungal organisms in mosque carpets in Riyadh, suggesting the need for implementing new strategies and laws to increase the level of hygiene awareness among worshipers and mosque caretakers to limit the spread of foot fungal infections.

This study examined the influence of biochar addition on fungal community during composting of cow manure using high-throughput sequencing. Two treatments were set up, including compost of cow manure plus 10% biochar (BC) and cow manure compost without biochar (CK). Fungal community composition varied obviously during composting in both treatments, and main fungi included Aspergillus, Myriococcum, Thermomyces, Mycothermus, Scedosporium, Cladosporium, and unclassified Microascaceae. Fungal community composition was altered by biochar during composting, especially during the thermophilic and the cooling phase, promoting Aspergillus and Myriococcum while inhibiting unclassified Microascaceae and Thermomyces. Based on linear discriminant analysis effect size analysis, common indicator groups were detected in both composts; however, specific indicator groups were also found in BC treatment, including Clavicipitaceae, Tremellales, Gibberella, and Coprinopsis. Canonical correspondence analysis (CCA) indicated that moisture content, organic matter, C/N, and pH had significant correlation (p < 0.05) with fungal composition in both treatments. However, in compost added with biochar, temperature was not an important factor affecting fungal community (p > 0.05).