Mercury determination in environmental samples using EDXRF and CV-AAS

✍ Scribed by T. H. Nguyen; J. Boman; M. Leermakers; W. Baeyens

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 235 KB
• Volume: 27
• Category: Article
• ISSN: 0049-8246
• DOI: 10.1002/(sici)1097-4539(199807/08)27:4<277::aid-xrs297>3.0.co;2-u

✦ Synopsis

The determination of total Hg in various environmental matrices was investigated using energy-dispersive x-ray Ñuorescence (EDXRF) spectrometry on both powdered and digested samples and cold vapor atomic absorption spectrometry (CV-AAS) on digested samples. Several microwave decomposition procedures were evaluated. The use of di †erent acid mixtures, microwave power settings and decomposition times were compared, in addition to the analysis of wet and freeze dried samples. A set of standard reference samples were used to evaluate the procedures. An mixture was found to be optimal for the complete mineralization and digestion of H 2 SO 4 -HNO 3 -H 2 O 2 biological samples for Hg by CV-AAS, whereas for EDXRF both and mix-HNO 3 -H 2 O 2 H 2 SO 4 -HNO 3 -H 2 O 2 tures gave good results. The detection limit of EDXRF could be signiÐcantly decreased (from 0.2 lg g-1 to 0.058 lg g-1) by performing the analysis on digested samples. Good agreement was obtained between the EDXRF and CV-AAS analysis. The results were also in good agreement with certiÐed values. The methods were applied to environmental samples (coal, vegetation, Ðsh and sediment) and human hair in a coal mining area and in locations where coal is used for cooking in Vietnam.