Table 4.

Regression results of the association between ambient air pollutants and intestinal bacteria.

Bacteria impacted1	Pollutants2	Adjusted coefficients3	P value
Phylum Actinobacteria
Family Bifidobacteriaceae	PM10	1.60 × 10−3	0.013
	PM2.5	3.90 × 10−4	0.003
	NO2	1.19 × 10−3	0.004
	SO2	4.06 × 10−3	0.010
Phylum Proteobacteria
Family Enterobacteriaceae	PM10	1.60 × 10−3	0.013
	PM2.5	1.02 × 10−3	0.022
	NO2	3.70 × 10−3	0.008
	SO2	1.35 × 10−2	0.011
Family Phyllobacteriaceae	PM10	−1.72 × 10−5	0.002
	PM2.5	−1.13 × 10−5	0.002
	NO2	−2.57 × 10−5	0.037
	SO2	−1.47 × 10−4	0.001
Phylum Bacteroidetes
Family Porphyromonadaceae	SO2	−8.33 × 10−4	0.014
Phylum Firmicutes
Family Clostridiaceae 1	NO2	−4.73 × 10−4	0.024
Genus Lactobacillus	PM10	−1.04 × 10−4	0.014
	PM2.5	−7.78 × 10−5	0.005
	NO2	−2.01 × 10−4	0.035
	SO2	−8.48 × 10−4	0.015
Genus Clostridium sensu stricto 1	PM2.5	−6.70 × 10−5	0.025
	NO2	−2.39 × 10−4	0.008
	SO2	−7.80 × 10−4	0.031
Species Eubacterium dolichum	SO2	−9.09 × 10−4	0.007

¹Dependent variable; ²independent variable; ³single pollutant model, adjusted by dietary intake. Only taxa with significant difference (P < 0.05) were shown.