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The applicability and usefulness of k -based reactor neutron activation analysis (NAA) in the life sciences is evaluated from the following examples: 1. Instrumental NAA of NIST SRM 1633a coal fly ash, as a quality assessment; 2. Radiochemical NAA of Versieck's reference human serum, and-herewith associated-the development of practical correction procedures for neutron-induced reaction interferences and of improved methods to evaluate the detection efficiency and the correction for true coincidence; and 3. Determination of the lanthanides in plant leaves and lichens near a Portuguese coal-fired power station, which led to the introduction of the Westcott formalism and to the use of a low-energy photon detector. As concluded, k -based NAA is at present capable of tackling a large variety of analytical problems when it comes to the multielement determination in environmental and biological matrices. [ABSTRACT FROM AUTHOR]

The epiphytic lichen Parmelia sulcata was collected in the neighborhood of a Portuguese coal-fired power station (Sines coal power station) as monitor for heavy metal air pollution. A study of the metal contents variability along 1991 and 1992 was performed. The heavy metals Ag, As, Br, Co, Cr, Fe, Hg, Sb, Se, and Zn were determined by k -based instrumental neutron activation analysis. The concentrations found in 1991 and 1992 show an accumulating process of Co and Fe (≈5%/mo) and of Cr and Sb (≈7%/mo). Low accumulation is observed for Ag, Se, and Zn (≈2%/mo), and no concentration variation is observed for As, Br, and Hg. It is concluded that the metal accumulation observed is the result of the nearby ash and coal deposits. [ABSTRACT FROM AUTHOR]

The applicability and usefulness of k0-based reactor neutron activation analysis (NAA) in the life sciences is evaluated from the following examples: 1. Instrumental NAA of NIST SRM 1633a coal fly ash, as a quality assessment; 2. Radiochemical NAA of Versieck's reference human serum, and--herewith associated--the development of practical correction procedures for neutron-induced reaction interferences and of improved methods to evaluate the detection efficiency and the correction for true coincidence; and 3. Determination of the lanthanides in plant leaves and lichens near a Portuguese coal-fired power station, which led to the introduction of the Westcott formalism and to the use of a low-energy photon detector. As concluded, k0-based NAA is at present capable of tackling a large variety of analytical problems when it comes to the multielement determination in environmental and biological matrices.

The epiphytic lichen Parmelia sulcata was collected in the neighborhood of a Portuguese coal-fired power station (Sines coal power station) as monitor for heavy metal air pollution. A study of the metal contents variability along 1991 and 1992 was performed. The heavy metals Ag, As, Br, Co, Cr, Fe, Hg, Sb, Se, and Zn were determined by k0-based instrumental neutron activation analysis. The concentrations found in 1991 and 1992 show an accumulating process of Co and Fe (approximately 5%/mo) and of Cr and Sb (approximately 7%/mo). Low accumulation is observed for Ag, Se, and Zn (approximately 2%/mo), and no concentration variation is observed for As, Br, and Hg. It is concluded that the metal accumulation observed is the result of the nearby ash and coal deposits.