Altered composition of the Indonesian gut microbiome and heavy metal resistance genes abundance in response to heavy metal exposure

Exposure to heavy metals poses significant health risks through inhalation, ingestion, and contact with contaminants, potentially causing gastrointestinal disorders and heightened infection vulnerability by altering the gut microbiome. In Indonesia, heavy metal contamination and its impact on the gut microbiome remain underexplored. This study assessed heavy metal prevalence in stool samples from coastal and highland populations and its potential microbiome effects. Copper (Cu), barium (Ba), manganese (Mn), and zinc (Zn) were detected, with barium contamination particularly concerning (13 of 20 participants). Genes for heavy metal resistance, such as znuC, nikE, modC, mntH, and arsB, were common in both populations. Copper levels negatively correlated with Prevotella abundance, while barium levels positively correlated with Prevotella, Faecalibacterium, and Ruminococcus abundance, indicating an antagonistic Ba-Cu relationship in shaping the microbiome. This study highlights the health risks of heavy metal exposure in Indonesia and its potential impact on gut microbiome composition.