MICROEMULSION DETERMINATION OF LEAD AND CADMIUM IN SAUDI-ARABIAN PETROLEUM-PRODUCTS BY INDUCTIVELY-COUPLED PLASMA-MASS SPECTROMETRY (ICP MS)

The concentrations of lead and cadmium were determined in Saudi Arabian petroleum products by inductively coupled plasma mass spectrometry (ICP/MS). A microemulsion procedure was used for sample pretreatments while the standard addition method was used for sample analysis. Detection limits were 0.006-0.160 mug/g lead and 0.015-0.170 mug/g cadmium in petroleum product samples. Recoveries of added lead and cadmium as oil soluble salts were made and found to be in the 99-103% and 100-101% ranges, respectively. The mean lead and cadmium levels in aviation turbine oil were 0.16 and 0.17 mug/g, and in diesel fuel oil were 0.35 and 0.01 mug/g, respectively whereas in leaded motor gasoline, the concentrations were 901.00 and 0.085 mug/g, respectively. The percentage relative standard deviations for five replicate samples were < 5% in all cases. The results are discussed in relation to the sources of the metals, and the possible environmental impact and health risks.