Heavy Metal Pollution of Surface Soil in the Thrace Region, Turkey

Abstact Samples of surface soil were collected at 73 sites in the Thrace region, northwest part of Turkey. Two complementary analytical techniques, epithermal neutron activation analysis (ENAA) and atomic absorption spectrometry (AAS) with flame and graphite furnace atomization were used to determine 35 elements in the soil samples. Concentrations of As, Cd, Co, Cu, Mn, Ni, Pb and Zn were determined using AAS and GF AAS, and ENAA was used for the remaining 27 elements. Results for As, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Cu Eu, Fe, Hf, I, In, K, La, Mn, Mo, Na, Nd, Ni, Pb, Rb, Sb, Sc, Sm, Sr, Ta, Tb, Th, Ti, U, V and Zn are reported for the first time for soils from this region. The results show that concentrations of most elements were little affected by the industrial and other anthropogenic activities performed in region. Except for distinctly higher levels of Pb, Cu, Cd and Zn in Istanbul district than the median values for the Thrace region, the observed distributions seem to be mainly associated with lithogenic variations. Spatial distributions of As, Cd, Cr, Cu, Ni, Pb and Zn were plotted in relation to the concentration values in soil using Geographic Information System (GIS) technology     

Characterisation of individual aerosol particles on moss surfaces: implications for source apportionment

The size, morphology and chemical composition of 8405 particles on moss surfaces (Hylocomium splendens) was investigated by scanning electron microscopy and energy-dispersive X-ray microanalysis. Two moss samples from three locations in Southern Norway (Alg?rd, Birkeland, Neslandsvatn) and two sampling years (1977 and 2005) each were selected leading to a total of 12 samples investigated. At all three locations, particle deposition decreased substantially with time. The major particle groups encountered include silicates, iron-rich silicates, metal oxides/hydroxides, iron oxides/hydroxides, carbonates, carbon-rich particles, silicate fly ashes, iron-rich silicate fly ashes, and iron oxide fly ashes. Between 1977 and 2005, the relative number abundance of the three fly ash groups decreased substantially from approximately 30-60% to 10-18% for the small particles (equivalent projected area diameter <1 microm), and from 10-35% to 2-9% for large particles with diameters ≥1 microm. This decrease of fly ash particles with time was overlooked in previous papers on atmospheric input of pollutants into ecosystems in Southern Norway. In general, the presence of fly ash particles is ignored in most source apportionment studies based on bulk chemical analysis. Consequently, the geogenic component (crustal component) derived from principal component analysis is overestimated systematically, as it has a similar chemical composition as the fly ash particles. The high abundance of fly ashes demonstrates the need to complement source apportionment based on bulk chemistry by scanning electron microscopy in order to avoid misclassification of this important anthropogenic aerosol component.     

Painted surfaces--important sources of polychlorinated biphenyls (PCBs) contamination to the urban and marine environment

A study of a large number of samples of flaking old paint from various buildings in Bergen, Norway (N = 68) suggests that paint may be the most important contemporary source of PCBs in this urban environment with concentrations of PCB₇ up to 3.39 g/kg. Twenty-three of the samples were collected from a single building, and the concentrations were found to vary over 3 orders of magnitude. In addition, 16 concrete samples from a large bridge previously coated with PCB-containing paint were collected and separated into outer- and inner samples indicating that PCBs are still present in high concentrations subsequent to renovation. PCBs were found in several categories of paint from wooden and concrete buildings, potentially introduced to the environment by natural weathering, renovation, and volatilization. Consequently, this dispersion may lead to increased levels of PCBs in urban atmospheres, soils, and harbor sediments where high concentrations have resulted in Governmental advice against consumption of certain seafood.     

Temporal trends (1990-2000) in the concentration of cadmium, lead and mercury in mosses across Europe

The European heavy metals in mosses survey provides data on the concentration of 10 heavy metals in naturally growing mosses. The survey has been repeated at five-yearly intervals and in this paper we report on the temporal trends in the concentration of cadmium, lead and mercury between 1990 and 2000. Metal- and country-specific temporal trends were observed. In general, the concentration of lead and cadmium in mosses decreased between 1990 and 2000; the decline was higher for lead than cadmium. For mercury not enough data were available to establish temporal trends between 1990 and 1995, but between 1995 and 2000 the mercury concentration in mosses did not change across Europe. The observed temporal trends for the concentrations in mosses were similar to the trends reported for the modelled total deposition of cadmium, lead and mercury in Europe.     

POP exposure from fish liver consumption and risk of cancer--the Norwegian Women and Cancer Study

The aim of the study was to investigate the hypothesis that consumption of fish liver increases cancer risk in humans due to increased intake of persistent organic pollutants (POPs). This study is based on data from the Norwegian Women and Cancer Study (NOWAC). The study has a prospective cohort design with questionnaire data from 64 285 randomly selected Norwegian women (aged 40-70 at baseline) and linkage to the Norwegian Cancer Registry. Cox proportional hazards regression was used to calculate risk ratios associated with consumption of fish liver and total cancer and cancer in breast, uterus, and colon. Fish liver consumption was, after adjusting for known risk factors, associated with a significant reduced risk for total cancer (RR = 0.92, 95% CI: 0.85, 0.99), and non-significant reduced risk for breast cancer (RR = 0.90, 95% CI: 0.78, 1.04), and colon cancer (RR = 0.82, 95% CI: 0.63, 1.07). Relative risk for uterus cancer was 0.82 (95% CI: 0.61-1.12). No significant dose-response effect was found for frequency of fish liver consumption (when divided into three intake groups) and total cancer, nor for any of the other cancer sites.We have concluded that in Norwegian women, fish liver consumption was not associated with an increased cancer risk in breast, uterus, or colon. In contrast, a decreased risk for total cancer was found.     

Principal component analysis of data for trace elements and main components in precipitation falling on Norway

Trace elements and the main components in precipitation were measured at three background sites in Norway. The work is based on weekly samples from 1989 and 1990. Principal component analysis was used to detect the covariation of the chemical components in the data set. Dominant factors are long-range atmospheric transport of anthropogenic components to Norway, crustal material, and marine sources. Different local sources also exist. The interpretation of seasonal variations in the data set is eased by studying the changes in the factor scores throughout the year. Distinct seasonal patterns are shown for some of the factors, in particular those representing soil dust and atmospheric transport from the marine environment.     

Analysis of selected biomonitors to evaluate the suitability for their complementary use in monitoring trace element atmospheric deposition

The biomonitoring properties of oak tree bark compared with the epiphytic moss Hypnum cupressiforme and the influence of the tree bark, as its growth substrate, on the content of heavy metals in moss were investigated. Samples of the epiphytic moss H. cupressiforme and oak tree bark (Quercus spp.) were collected in Eastern Romania at a total of 44 sampling sites. Parallel moss and bark samples were collected from the same sides of the trunk circumference. V, Cr, Ni, Cu, Zn, As, Mo, Cd, In, Tl, Sn, Pb, and Bi were determined by ICP-MS. Principal component analysis was used to identify possible sources of metals in bark and moss. Six factors explaining 87 % of the total variance in the data set were chosen. The main factors represent long-range atmospheric transport of elements (Zn, Cd, (Pb), Bi, (Mo), (Tl)), local emissions from industrial sources (As, Cr, Ni, V), road traffic (Pb, Zn) and agricultural activities (Cu, (Zn)). The element concentrations in moss and bark samples are of the same order of magnitude. For almost all the elements, higher concentrations were obtained in moss. Significant correlations between concentrations in moss and bark samples were obtained for 7 of the 13 elements: V, Ni, Cu, Zn, Cd, In, and Bi, all typical anthropogenic pollutants. The use of tree bark for monitoring purposes might be an alternative in areas where there is a scarcity of mosses.     

Effect of chemical pollution on forms of 137Cs, 90Sr and 239,240Pu in arctic soil studied by sequential extraction

The aim of the present study was to determine the forms of 137Cs, 90Sr and 239,240Pu occurring in different soil horizons using sequential extraction of samples taken from four sites located along a pollution gradient from the copper-nickel smelter at Monchegorsk in the Kola Peninsula, Russia, and from a reference site in Finnish Lapland in 1997. A selective sequential-leaching procedure was employed using a modification of the method of Tessier, Cambell and Bisson ((1979). Analytical Chemistry, 51, 844-851). For 137Cs the organic (O) and uppermost mineral (E1) layer were studied, for 90Sr and 239,240Pu only the uppermost organic layer (Of). The fraction of 137Cs occurring in readily exchangeable form in the organic layer was about 50% at the reference site and decreased as a function of pollution, being 15% at the most polluted site in the Kola Peninsula. There was a clear positive correlation in the O layer between the distance from the smelter and the percentage of 137Cs extracted in the readily exchangeable fraction (Spearman correlation rsp = 0.7805, p = 0.0001), whereas in the E1 layer no correlation was evident. The distribution of 90Sr in the Of layer was similar at all sites, with the highest amounts occurring in exchangeable form and bound to organic matter, whereas stable Sr showed a somewhat different distribution with the highest amount in the oxide fraction. Most of the 239,240Pu was bound to organic matter. Chemical pollution affected the exchangeable fraction of 239,240Pu, which was about 1% at the most polluted site and 4-6% at the other sites.     

Distribution of 90Sr and 137Cs in Arctic soil profiles polluted by heavy metals

Effects of industrial pollution on the behaviour of radionuclides in spruce forest ecosystems were studied along a gradient from of a copper-nickel smelter in Monchegorsk, NW Russia. A reference site was situated in Lapland, Finland, 152 km west of Monchegorsk. Most of the total 137Cs activity in soil was in mineral (E and B) horizons, except at the reference site where the major part was still in the organic surface layer. Most of the total 90Sr activity still remaining in the soil profile was found in the surface layer, but the relative amount decreased with increasing level of industrial pollution. Pollutants from the smelter clearly affected the chemical speciation of radionuclides. Smaller amounts of exchangeable radionuclides were present in the organic surface layer at the most polluted sites. The decline of 137Cs with decreasing distance from the smelter correlated strongly with a similar depletion in exchangeable K and Mg. Total concentrations of 137Cs and 90Sr showed high correlations with exchangeable cations, particularly in the E and upper B horizon. A sudden change in behaviour of 137Cs in the lower B horizon may be associated with changes in clay mineralogy along the soil profile caused by weathering.     

Estimation of metal uptake efficiencies from precipitation in mosses in Lithuania

The main sources contributing to heavy metal content in mosses in Lithuania were examined by a comparison of heavy metal concentrations in moss and corresponding deposition levels calculated from bulk deposition analysis. Bulk deposition was collected in open areas as well as under the canopy of trees. Uptake efficiencies in moss were calculated for Cd, Cr, Cu, Fe, Mn, Ni, V and Zn. All elements in moss except Pb and Cd appeared to be more or less influenced by sources other than air pollution. The general order of this influence on the heavy metal content in moss was observed as follows: Ni < V < Cr < Zn < Fe < Mn. The contents of Mn and Zn in moss were greatly influenced by leaching from the canopy while Pb was the only element which showed a net metal retention by the canopy. Concentrations of Fe and Cr in moss were dominating due to contribution from soil dust.