Study On The Method Of Rapid Test For Trace Heavy Metals In The Air Of Workplaces

Objective:To find a method of digesting membranes rapidly and simultaneously determining trace heavy metals of Pb, Cd, Cu, Co, Ni and Zn in the air of workplaces.Methods: In the paper, trace heavy metals of Pb, Cd, Cu, Co, Ni and Zn in the the air of workplaces were pretreated by microwave digestion (at 180℃, 20atm , 800w) and concentrated by absorption on chitosan (at pH = 5.0, 20℃~30℃),Determined Co, Cu, Pb , Ni, Cd and Zn in digesting liquids with direct flame atomic absorption spectrophotometry.Results: Microwave digestion relative standard deviation (RSD) range of 3.0% ~12.7% was significantly higher than mixed acid method of 6.7%~22%, indicated good precision compared with the mixed acid method; The detection limit of this method was 3.17ng/ml for Pb, 0.42 ng/ml for Cd , 2.42 ng/ml for Cu, 4.85 ng/ml for Co, 5.47ng/ml for Ni and 0.51ng/ml for Zn;Standard linear correlation (r) were of the range 0.9991~0.9999; Recovery ratio were of the range 91.3%~108.4%; The standard reference materials was used as quality control standards and the analysis results conformed well to the certified values, the sample results have no significance different(P﹥0.05)compared with graphite furnace atomic absorption spectyometry.Conclusion: The method was simple, rapid , accurate and highly sensitive. It was suitable for determining trace heavy metals of Pb, Cd, Cu, Co, Ni and Zn in the air of workplaces.