Prevalence of Antibiotic Resistance Genes, Heavy Metal Resistance Genes and the Class 1 Integron Gene in Well Water and Tap Water Samples from Four Cities in Henan Province, China

The presence of multi-resistance to both antibiotics and heavy metals in drinking water poses a significant risk to human health. Herein, we utilized qPCR to assess patterns of antibiotic resistance genes (ARGs), heavy metal resistance genes (HMRGs), and class 1 integron (intI1) gene expression levels in well and tap water samples from four cities in Henan Province, China. The relative abundance of most index values was higher in well water relative to tap water, or was highest in Shangqiu City and lowest in Puyang City on average. The expression of ARG was closely correlated with that of intI1 and HMRG in both well and tap water. Overall, our data highlighted the health threat posed by ARGs in the drinking water supply and underscore the potential for the transfer of these genes between bacteria with the aid of intI1 under selective pressure associated with human activity and heavy metal stress.