American J. of Engineering and Applied Sciences 4 (3): 355-362, 2011

Optimization of Energy Dispersive X-Ray FluorescenceSpectrometer to Analyze Heavy Metals in Moss Samples

1Mohd Zahari Abdullah, 3Ahmad Saat and 2Zaini Hamzah
1Department of Chemistry, Faculty of Applied Sciences,
University Technology MARA, Kampus Pahang 24600, Malaysia
2Department of Chemistry, Faculty of Applied Sciences,
University Technology MARA, 40450 Shah Alam, Malaysia
3Institute of Science, University Technology MARA, 40450 Shah Alam, Malaysia

Abstract: Problem statement: Mosses have been widely used as bioindicator especially to study the levels of trace metals pollutants in the surrounding ambient air because of their high efficiency to accumulate heavy metals contamination. There has been increasing demand to get a suitable analytical tools to determine the chemical contents of moss samples in this type of media. Therefore, this study was conducted with the aims to get one of the best analytical methods for the analysis of moss samples. Approach: Despite the various spectroscopic techniques that normally used to analyzed heavy metals in moss, each of these techniques has its advantages and disadvantages which been summarized elsewhere. We try not to use any chemical to decompose the samples where the samples were analyzed directly in its solid form by Energy Dispersive X-Ray Fluoresence Spectrometer, EDXRF technique. The EDXRF technique optimized for its main analytical parameters. Calibration procedure was made based on the in-house standard samples. The reliability of the optimized analytical procedure was established by analyzing two certified reference materials, Pine Needle, NIST 1575 and Lichen, IAEA-336. Results: The results showed that the metals could be analyzed with percent recoveries range within 84-102% for Pine Needle and 92-125% for Lichen. The possible factors influencing the percent recoveries of the elements were discussed in details. Conclusion: On overall, it is strongly suggest that the applied EDXRF method is adequate enough to analysis the heavy metal contents in moss samples even at very small concentration with high accuracy and precisely.

Key words: Heavy metals, contamination factor, terrestrial moss, petroleum industry