The metals Cd, Pb, and Zn occurring in Haplorthods and Haplumbrepts of both sandy and loamy textures in the vicinity of Tarnowskie Gory in southwest Poland, an area that has been subjected to severe metal contamination, were studied according to a procedure based on sequential extraction analysis. Concentrations of the metals ranged from background levels to levels well in excess of the maximum tolerable limits in agricultural soils. Thus, Cd, Pb, and Zn ranged from 0.2 to 103, 14 to 7100 and 20 to 10 000 mg kg−1 soil, respectively. Soil type, texture, organic matter, and cation exchange capacity (CEC) did not influence the relative proportions of heavy metal forms in any consistent manner. However, the influence of soil pH was clear. Soil samples of pH < 5.6 contained relatively more of all metals in the exchangeable form than in samples where pH was >5.6. The most consistent distribution patterns were found when the soil samples were grouped according to their total metal contents. The inferred relative mobility of the metals and their redistribution among the different fractions are generally consistent with the findings of previous studies of contaminated soils and support the view that metals from anthropogenic sources are more mobile than those from soil parent materials.

The surface sediments of the San Simon inlet of the Ria de Vigo in Galitia, north-west Spain contain heavy metal concentrations largely within the range to be expected if these metals were derived from detrital

Total concentrations and chemical forms of metals in surface sediments of the Vigo Ria (NW Iberian Peninsula) were determined following the sequential extraction method proposed by Tessier et al. (1979). Total values ranged from 7 to 14 µgCo g-1 , 52 to 76 µgCr g-1 , 18 to 82 µgCu g-1 , 136 to 209 µgMn g-1 , 18 to 30 µgNi g-1 , 24 to 112 µgPb g-1 , 62 to 185 µgZn g-1 and 18 to 34 mg g-1 for Fe. The distribution of metals is strongly influenced by the presence of urban and industrial centres. A decreasing concentration trend was observed towards (i) the outer-oceanic part of the ria and (ii) the northern shore in the middle part. Cobalt, Cr, Fe, Mn, and Ni were found to be strongly associated with the residual fraction of the sediment (65-78%), whereas Cu is significantly present in the oxidisable phase (34-72%) and Pb and Zn are found in both the reducible (14-49%) and the oxidisable (14-39%) phases. The speciation patterns reflect natural uncontaminated conditions in the outer part of the ria. However, a significant fraction of the Cu, Pb, and Zn in the sediments of the southern margin of the middle part of the ria, which supports most of the population and industrial activities, is present in labile forms, so a potential pollution risk may exist.