Effects of heavy metals on the viability of A549 cells

Abstract

Heavy metals, such as Cd and Pb, are present in the particulate matter (PM) suspended in ambient air. Once internalized, they often accumulate in the human body and cannot be metabolized for long periods. Most previous studies on Cd and Pb metabolism used high concentrations of these heavy metals. In this study, we analysed the effects of low concentrations of Cd or Pb (similar to their concentrations in the PM) on the viability of lung epithelial cells and the secretion of pro-inflammatory factors, IL-6 and IL-8. A549 cells were cultured in the presence of Cd and Pb at 1 µg/L and 1 mg/L for 0, 4, 12, and 24 h and analysed using WST-8 and lactate dehydrogenase (LDH) assays and ELISA. Our results revealed that Cd and Pb induced comparable cytotoxicity and secretion of pro-inflammatory cytokines, IL-6 and IL-8, in a time-dependent manner, even at low concentrations. Altogether, our results suggest that heavy metals present in PM can cause chronic long-term effects on human lungs.