Carbonaceous Nanoparticle Toxicity as a Function of Ferrous Iron Content

Experiments on mitochondria indicate that the toxicity of atmospheric nanoparticles correlates with both ferrous iron (Fe(II)) and anthracene concentrations in collected ultrafine particles (UFP). To further understand underlying chemical mechanisms responsible for this detrimental effect, UFPs and carbonaceous nanoparticles are investigated under near physiological conditions while analyzing Fe(II) and the most prevalent oxidative species hydrogen peroxide (H2O2). Realistic concentrations of Fe(II) at sub-nanomolar and H2O2 at nanomolar levels are quantified using flow injection analysis (FIA) with chemiluminescence. Results from this study will allow for better pinpointing of the main culprit in the toxicity of inhalable carbonaceous particles that are emitted from the incomplete combustion of fossil fuel. Results have shown in particular that in the presence of a biological electron donor, such as ascorbate, hydrogen peroxide is produced under physiological conditions