20 research outputs found
22.Elemental Characterization of Himalayan Airborne Particulate Matter Collected at 5,100 m a.s.l.
Caratterizzazione del PTS, PM10, PM5 raccolto nalla stazione CNR Ev K2 Laboratory-Observatory a 5100 ms.l.m in the Himalaya-Khumbu Valley, Nepal . Determinati più di 30 elementi e i fattori di arricchimaento dall'analisi dei suoli local
INAA for the determination of trace elements and evaluation of their enrichment factors in lichens of high altitude areas
Trace element (TE) characterization and analysis in epiphytic lichens collected in different areas of the Himalayas (Nepal) and of the Alps (Italy) is presented. The results give information for the assessment of TE distribution present in the two different areas. The evaluation of the enrichment factors may provide information for many elements about their association to long-distance atmospheric transport phenomena. To this purpose, samples of superficial soils, collected in the same areas of those of the lichens, have also been analyzed. Most of the trace elements were determined by instrumental neutron activation analysis (INAA), while lead and cadmium measurements were carried out with electrothermal atomic absorption spectroscopy (ET-AAS)
Determination of baseline element composition of lichens using samples from high elevations
The results of a survey aimed at providing baseline element composition of lichens from unpolluted or very low
polluted areas are reported. Lichen samples collected at high elevation areas in Himalayas (Nepal), Mt. Kenya (Kenya)
and the Alps (Italy) were analyzed for their trace element content, mostly by INAA, allowing for a multi-element
analysis. The elemental composition of lichen samples was essentially influenced by natural occurrence, mainly airborne
soil dust. However, also anthropogenic input determined by long-distance atmospheric transport of pollutants was
involved for some highly volatile elements such as Br, Cd and Sb. To avoid the influence of soil contamination and air
pollution, and obtain baseline concentrations to be used as reference (the ‘‘natural’’ elemental composition of lichens),
the average of the lowest concentrations is suggested
Determination of Trace Elements by INAA in Urban Air Particulate Matter and in Transplanted Lichens
Lichens as biomonitors and neutron activation analysis as analytical technique have been employed to evaluate the trace element atmospheric
pollution in the metropolitan area of the city of Pavia (Northern Italy). Transplanted lichens (Parmelia sulcata and Usnea gr. hirta) and air
particulate matter have been monthly collected and analyzed during the winter 2001 2002. INAA and ET-AAS have been used for the
determination of 28 elements in air particulate matter and 25 elements in lichens. Trace metals concentrations as well as the corresponding
enrichment factors were evaluated and compared