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Sometimes, the preparation of a plant sample to GC analysis undergoes the stage of drying plant ex-tract from the solvent, and subsequently the repeated extraction of the dry residue in a different solvent. The purpose of this procedure is to separate the studied phenolic compounds from the matrix. This paper presents the results of the research into the effect of the type of solvent used in the proceeding (methanol, water, acetone, diethyl ether or chloroform) on the size of losses in the phenolic compounds during such a procedure. It has been noted that the greatest recovery appears in cases of methanol and acetone, whereas water may be the source of considerable losses in the compounds during the preparation of the plant sample for analysis.
The distribution of polycyclic aromatic hydrocarbons (PAHs) in plant and organic soil from 14 peatland sites in NE Poland and 7 peatland sites in SE Poland have been investigated. The total PAH concentration in the leaves of Ledum palustre collected from peatlands in NE Poland ranged from 232 ng/g to 1523 ng/g and was higher than the total PAH concentration in pine needles (Pinus sylvestris) taken from those same peatlands (the values ranged from 181 to307 ng/g). A similar trend was observed in the case of plants from the peatlands in SE Poland, except that the overall PAH concentration in the majority of the plant samples was found to be higher than those found in NE Poland. Phenanthrene and fluoranthene had the biggest share in the overall PAH concentration in all the peat and plant samples. The lack of 5- and 6-ringed PAHs in the plant and soil material indicates the lack of any direct emission sources of these compounds in regions adjacent to those examined in the study. Total sum of PAH pollution levels in peats and plants as well as vertical distribution of the concentrations in the soil profile of particular study sites integrates long-range pollution sources. To compare natural and antropogenic PAH input in the pealtlands, we have used parent PAH ratios: ANT/(ANT&PHE); FLT/(FLT&PYR). Our data suggest that PAHs with four and more rings do not allow a simple segregation into combustion or petroleum sources.
Concentrations of accumulated heavy metals were compared between the terrestrial bryophyte Pohlia nutans and needles and bark of Larix decidua collected on a dump situated in the vicinity of coke- and sulphuric acid-producing factories and a municipal thermal-electric power station. The dump consisted of heavily polluted mine and smelter wastes located near Walbrzych (southwestern Poland). The plant samples were compared with material of the same species from the control site. In the examined area needles and bark can be considered as suitable biomonitors for atmospheric pollution for Co, Cu, Ni and Pb. Bioaccumulation abilities of Pb in P. nutans and L. decidua needles and Ni in P. nutans and L. decidua bark were similar. Compared to each other needles were better accumulators of Ni and the moss P. nutans was a better accumulator of Co and Cu. P. nutans was a better accumulator of Co, Cu and Pb compared to bark.
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