In order to investigate the relationship between air pollution and the respiratory
tract microbiota, 114 healthy volunteers aged 18-21 years were selected during the
winter heating period in Northeast China; 35 from a lightly polluted region (group
A), 40 from a moderately polluted region (group B) and 39 from a heavily polluted
region (group C). Microbial genome DNA was extracted from throat swab samples to study
the oral flora composition of the volunteers by amplifying and sequencing the V3 regions
of prokaryotic 16S rRNA. Lung function tests were also performed. The relative abundance
of Bacteroidetes and Fusobacteria were significantly lower and Firmicutes Proteonacteria
and Actinobacteria higher in participants from polluted regions. Within bacteria classes,
Bacterioida abundance was lower and Clostridia abundance higher in polluted areas,
which was also reflected in the order of abundance. In samples from region C, the
abundance of Prevotellaceae, Veillonellaceae, Porphyromonadaceae, Fusobacteriaceae
Paraprevollaceae and Flavobacteriaceae were lowest among the 3 regions studied, whereas
the abundance of Lachnospiraceae and Ruminococcaceae were the highest. From group
A to group C, the relative class abundances of Prevotella, Veillonella, Fusobacterium,
Camphylobacter and Capnocytophaga Porphyromonas, Peptostreptococcus and Moraxella
became lower in polluted areas. Pulmonary function correlated with air pollution and
the oropharyngeal microbiota differed within regions of high, medium and low air pollution.
Thus, during the winter heating period in Northeast China, the imbalance of the oropharyngeal
microbiota might be caused by air pollution and is likely associated with impairment
of lung function in young people.