Determination of heavy metals in airborne particulate matter by stripping voltammetry
Abstract
Trace metals were a dangerous composition in airborne particulate matter, which may cause hazardous diseases in human. Accurately determination of metal concentration is significant. The analysis needs to have high precision and accuracy. Therefore, the stripping voltammetry is a appropriate method for determination of trace metals, including Zn, Cd, Pb, Cu, Co, Ni. Various experimental parameters were studied and optimized. The detection limits of these metal ions were 3,47, 0,34, 0,59, 0,68, 2,51, 0,06 ppb for Zn(II), Cd(II), Pb(II), Cu(II), Ni(II) and Co(II), respectively, with very good accuracy (standard deviation is below 5%). Interference from coexisting ions was successfully investigated. The sample was digested by microwave oven with the recoveries from 96,7% to 106%. The great advantage of method is the simplicity, selectivity, and high sensitivity. The collection of particulate matter was performed from march to june, 2009, at different locations, which represent for residential, traffic and industrial areas. Metal concentrations spanned the range, the lowest was 0,06 ng/m3 for Co and the highest was 505 ng/m3 for Zn. Generaly, lead concentration was lower than TCVN 5937:2005 and range on 1,53-26,84 ng/ m3.