TABLE 1.

Effects of Pb on gut microbiome and host.

Model	Method	Dose	Time	Gut microbiota	Outcomes	References
Mice	Drinking water	2 ppm	Gestation and lactation	Cultivable anaerobes↑ Cultivable aerobes↓ Phylum: Firmicutes↑ Bacteroidetes↓ No significant changes in richness and diversity Genus: Desulfovibrionaceae, Barnesiella, Clostridium XIVb↑ Lactococcus, Akkermansia Enterorhabdus, Caulobacterales↓	Adult bodyweight change (male offspring)	Wu et al., 2016
Mice	Drinking water	10 ppm	4, 13 weeks	4 weeks Genus: S24-7_g↑ Clostridiales_f_g, Lachnospiraceae_Ruminococcus, Ruminococcaceae_g_, Ruminococcaceae_Oscillospira, Ruminococcaceae_Ruminococcus↓ 13 weeks Genus: Clostridiaceae_g_↑ Lachnospiraceae_Other, Lachnospiraceae_Blautia, Lachnospiraceae_Coprococcus, Lachnospiraceae_Ruminococcus, Ruminococcaceae_Other, Ruminococcaceae_Ruminococcus↓	Numerous microbial metabolic pathways alteration (vitamin E, bile acids, nitrogen metabolism, energy metabolism, oxidative stress, and the defense/detoxification mechanism)	Gao B. et al., 2017
Mice	Drinking water	1 g/L	4 weeks, 8 weeks	8 weeks Phylum: Proteobacteria, Verrucomicrobia↓ Genus: Parabacteroides↑; unclassified and uncultured Ruminococcaceae, Lachnospiraceae_incertae_sedis, Ruminiclostridium_9, Rikenellaceae_RC9_gut_group, Oscillibacter, Anaerotruncus, Lachnoclostridium, Akkermansia↓	/	Zhai et al., 2017a
Mice	Drinking water	0.1 mg/L	15 weeks	Phylum: Bacteroidetes↑ Firmicutes↓ Genus: Parabacteroides↑ Dehalobacterium↓	Hepatic lipid metabolism disruption Microbial metabolism alteration	Xia et al., 2018a
Mice	Drinking water	1 g/L	8 weeks	Genus: Ruminococcus↑ Turicibacter↓	Gut permeability↑ (Muc2, ZO-1, claudin-1, and occludin↓)	Zhai et al., 2019c
Mice	Drinking water	1 g/L	8 weeks	Phylum: Helicobacter↓ Lachnospiraceae_NK4A136_group↑	Hepatotoxicity, nephrotoxicity, oxidative damage; SCFAs (acetate, propionate, and butyrate)↓	Cheng et al., 2019
Japanese quails	Drinking water	50, 1,000 ppm	49 days	1,000 ppm Phylum: Bacteroidetes↑ Firmicutes, Actinobacteria↓ Genus: Bacteroides↑ Faecalibacterium, Bifidobacteria↓	Cecal structure disruption, intestinal inflammation, and immune disorder	Kou et al., 2019
Mice	Drinking water	100 ppm, 500 ppm	8 weeks	100 ppm Family: Lactobacillaceae, Erysipelotrichaceae↑ Lachnospiraceae↓ Genus: Turicibacter↑ Barnesiella, Alistipes↓	/	Breton et al., 2013b
Rats	Oral	333.21, 77.75, 19.44, and 4.86 mg/kg	2 weeks	Lactose-negative E. coli↑	E. coli attachment↑	Sadykov et al., 2009
Zebrafish	Water	10 and 30 μg/L	7 days	30 μg/L Phylum: Firmicutes, Bacteroidetes↑ Fusobacteria, Proteobacteria↓	Hepatic metabolism disturbance (glucose and lipid metabolism, amino acid metabolism, nucleotide metabolism)	Xia et al., 2018b
Zebrafish	Food	500 mg/kg	14 days	Phylum: Alphaproteobacteria↑ Gammaproteobacteria↓ Order: Alteromonadales↓ genus: Pseudomonas, Halomonadaceae, Arcobacter, Polaribacter↑	/	Patsiou et al., 2020
Human	/	/	/	Succinivibrionaceae, Gammaproteobacteria↑	/	Bisanz et al., 2014
Human	/	/	/	Proteobacteria, Burkholderiales↑	/	Eggers et al., 2019
Human	/	/	/	Lachnospiraceae, Eubacterium eligens, Ruminococcaceae UGG-014, Erysipelotrichaceae UCG-003, Tyzzerella 3, Bacteroides, Slackia, italics, and Roseburia↑ Prevotella 9↓	/	Shao and Zhu, 2020