The capacity of the PM2.5 to oxidize target molecules causing oxidative stress in cells through the formation of reactive oxygen species (ROS) is known as Oxidative Potential(OP). PM samples were collected using an SKC cascade impactor in November on roadside, urban and rural sites, concentration of OP are 315.9087011, 283.6803418,169.8538375 nmol/min/µg respectively. DTT assay was used to determine the concentration of OP. Blood samples of cancer patients were subsequently collected in Agra region from hospitals. The inductively coupled plasma mass spectrometry method was used for determining heavy metals in PM2.5 and blood samples. The PM2.5-bound average concentrations of Al, Cr, Cu, Fe, Mn, Ni, Pb, and Zn were 0.446, 0.036, 0.044, 0.392, 0.025, 0.006, 0.043, and 0.141 μg/m3, respectively. The distribution of these metals followed the order: Al (39.39%) >Fe (34.62%) >Zn (12.46%) >Cu (3.91%) >Pb (3.76%) >Cr (3.13%) >Mn (2.18%) >Ni (0.56%). In blood levels of heavy metals (Al, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) were 0.446, 0.087, 0.108, 16.723, 0.011, 0.025, 0.181, and 0.078 μg/L, respectively. The distribution of heavy metals in blood samples differed from that in PM2.5, indicating the various bioavailability of these heavy metals. These results provide rationale and limitations of the use of oxidative potential as an indicator of PM toxicity in toxicological studies. In addition, our results suggested that blood heavy metals levels are a good indicator for inhalable PM2.5-bound heavy metals intake. Moreover, personal exposure to ambient PM2.5-bound heavy metals and its relation with different health alteration in humans will be discussed in the presentation.
Keywords: Oxidative potential, heavy metals, Lung cancer.