Particulate matter pollution alters the bacterial community structure on the human skin with enriching the...

Particulate matter (PM) has been recognized as a significant environmental contaminant with substantial effects on human health, although the impact of PM pollution on the skin microbiota is less understood. In this study, 78 skin microbiota samples from volunteers were obtained during periods of haze and non-haze in the spring and winter. The diversity, composition, and co-occurrence networks of the skin bacterial community were revealed using high-throughput sequencing. Acinetobacter sp. XSB125 and Pseudomonas sp. XSB6 were isolated and cocultured with PM collected during haze days. Significant seasonal variations were observed in the skin bacterial community, with winter samples showing greater diversities than spring samples. Supervised partial least squares discriminant analysis indicated that PM pollution influenced the skin bacterial community composition. Stronger interactions were detected in the network structure of the skin bacterial community during haze days. Differential and random forest analyses revealed that Acinetobacter and Pseudomonas, which are important resistant opportunistic pathogens, were significantly enriched during haze days in winter. To confirm the increases in Acinetobacter and Pseudomonas during haze days, an Acinetobacter strain and a Pseudomonas strain were isolated and cultured with the PM we collected during haze days. In vitro experiments confirmed that PM promoted the growth of the Acinetobacter and Pseudomonas strains. Function analysis revealed increased metabolic function and enrichment of antibiotic resistance- and pathogenicity-related functions during haze days, including the beta-lactamase gene and attachment invasion locus protein. These findings reveal the complex interplay between PM pollution and the skin microbiota, highlighting the need for further research into mitigation strategies to protect the public health from PM exposure.