Distributions of arsenic and selenium in selected Chinese coal mines.
The contents of arsenic and selenium in 33 coals collected from the main coal mines in northeastern, northern and eastern China were determined by flow injection-hydride generation and non-dispersion atomic fluorescence spectrometry (HGAFS). The concentrations of As in the northeast region are relatively higher with the values > 100 microg g(-1); in the east they are lower with values < 100 microg g(-1). The contents of Se in these three areas are the opposite, most of them from the northeast mines are < 1 microg g(-1) and increase as the mine location advances south where the average contents are > 5 microg g(-1).
Evaluation of heavy metal and polycyclic aromatic hydrocarbons accumulation in plants from typical industrial sites: potential candidate in phytoremediation for co-contamination
The heavy metal and polycyclic aromatic hydrocarbons (PAHs) contents were evaluated in surface soil and plant samples of 18 wild species collected from 3 typical industrial sites in South Central China. The accumulative characteristics of the plant species for both heavy metal and PAHs were discussed. The simultaneous accumulation of heavy metal and PAHs in plant and soil was observed at all the investigated sites, although disparities in spatial distributions among sites occurred. Both plant and soil samples were characterized by high accumulation for heavy metal at smelting site, moderate enrichment at coke power and coal mining sites, whereas high level of PAHs (16 priority pollutants according to US Environmental Protection Agency) at coke power site, followed sequentially by coal mining and smelting sites. Based on the differences of heavy metal and PAH accumulation behaviors of the studied plant species, heavy metal and PAH accumulation strategies were suggested: Pteris vittata L. and Pteris cretica L. for As and PAHs, Boehmeria nivea (L.) Gaud for Pb, As, and PAHs, and Miscanthus floridulu (Labnll.) Warb for Cu and PAHs. These native plant species could be proposed as promising materials for heavy metal and PAHs combined pollution remediation.
Determination of trace elements in plant materials by slurry sampling graphite furnace AAS — some analytical problems
SummaryThe analytical conditions of cadmium, lead, nickel and cobalt determination in plant material by slurry sampling graphite furnace atomic absorption spectrometry (GFAAS) are presented. The results of stability tests for slurries prepared in different ways are also shown. The ratio of the amount of analyte found in the liquid phase to the total amount of analyte in the slurries is investigated. The determination results are calculated from aqueous standard calibration graphs (cobalt and nickel) or by the standard addition method (cadmium and lead). Statistical evaluation of the results from the certified materials indicate that the slurry method is both accurate and comparable in precision to the conventional wet-ashing procedure.