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Lead has been used extensively for thousands of years. Once introduced into the environment, like any other heavy metal, lead accumulates in soil and sediments. High lead concentrations in river and lake sediments can be harmful to aquatic organisms. At present, uncontaminated water sediments in the northern and central parts of Poland contain below 9 mg of lead per kg. The lakes located within the following lake districts: Greater Poland, Pomeranian and Masurian, provided 409 samples of surface sediments from deep spots (the profundal zone). All the samples were tested for the content of Pb and other selected macroelements. The content of Ca, Mg, Fe, K, Mn, Na, P, Pb and S was determined by ICP-OES and the total organic carbon (TOC) was evaluated by the coulometric titration method. The observed range of lead concentration was from below 3 to 222 mg kg-1. The average content was 37 mg kg-1, the geometric mean 30 mg kg-1, and the median 33 mg kg-1. In the majority of samples, the lead concentration was higher than the geochemical background. Only in 5.77% of the samples, the lead content was lower than 10 mg kg-1. The lead concentration in the sediments was relatively well correlated with the total organic carbon (r = 0.59), aluminium (r = 0.45) and sulphur (r = 0.47), moderately correlated with iron (r = 0.26) and potassium (r = 0.28), very weakly correlated with phosphorus (r = 0.12) and negatively correlated with the calcium concentration (r = -0.28). No correlation was observed for manganese (r = -0.05), magnesium (r = 0.07) and sodium (r = -0.07). Factor analysis revealed the presence of two factors that together accounted for nearly 45% of variation. The first factor included aluminium, potassium and magnesium, and the second one - sulphur and organic carbon. The lead share was low in the first factor (0.343), but very high in the second factor (0.757). Based on the results of the factor analysis, it can be assumed that lead in the organic matter-rich sediments of the profundal zone is deposited mainly in the form of sulphides. Lead concentration varied among the sediments obtained from various lake districts; it was lower in the lakes located within the Pomeranian Lake District than in those from Greater Poland and Masurian Lakes.
In the paper, the effects of differences in land use of a catchment and settlements on the variability of heavy metals concentrations (Zn, Pb, Cu, Cd, Ni) in the Narew River and some of its tributaries such as the Biebrza, upper Narew, Pisa, Omulew and Rozoga rivers were studied. The investigations continued from 1997 to 2002. The areas dewatered by the watercources differ considerably in terms of environmental features (forests, wetlands, bogs and water reservoirs), land use (arable lands, grasslands) and population (man-made areas). The total catchment of the Narew River at the cross-section in Zamski Kościelne was also taken into account. The urban areas make up from 0.5% of the Rozoga River to 2.5% of the upper Narew catchment. Water samples were collected quarterly (April, July, October and January) from four study sites located near the river mouth and were analyzed for Zn, Pb, Cu, Cd and Ni by the AAS method. The results showed that concentrations of Pb, Cu, Cd and Ni increased along the Narew River due to the accumulation of the elements in water. A significant influence on high heavy metal concentrations in water was produced by the town of Białystok, a source of large amounts of municipal pollutants discharged into the river. This mainly affected the content of Zn, as the highest pollution with this element was detected in the upper Narew River. The lowest Zn concentrations were observed in the Omulew River water, where forests dominated in the area, covering more than 48% of the catchment. The research showed that wetlands and lakes significantly decreased Pb, Cu, Cd and Ni concentrations in flowing water, but the presence of large inhabited areas with dense population and municipal pollution increased concentrations of heavy metals in river water.
The Legnica-Głogow Copper Mining District has been the site of metal mining for more than 50 years. Intensive environmental actions have, more recently, been aimed at reducing emissions of harmful substances in the region. We compared the blood lead concentrations of children resident in the copper smelting district in southwestern Poland in 1995 and 2007. The sample included 1,405 children, 7-15 years of age, resident in the same communities in the Legnica-Głogow Copper Mining District in 1995 (432 boys, 403 girls) and 2007 (279 boys, 291 girls). Blood samples were drawn (venipuncture) and analyzed for lead levels (Pb-B) with the same protocol in both years (atomic absorption spectrometry in a graphite furnace). Analysis of covariance, with age and age squared as covariates, was used to compare blood lead levels between years, regions (Głogow and Legnica), and genders. The prevalence of children with blood lead levels >6 μg/dl was compared between years, regions, and genders, and was compared with the chi square statistic (χ²). Blood lead level was significantly higher in 1995 (7.52±0.12 μg/dL) compared to 2007 (4.80±0.16 μg/dL), a decline of 2.72±0.19 μg/dL over the 12-year interval. Blood lead levels were higher in boys than in girls in each year, and declined between 1995 and 2007 in each gender, 8.61±0.16 μg/dL and 5.31±0.23 μg/dL, respectively, in boys, and 6.43±0.17 μg/dL and 4.29±0.22 μg/dL, respectively, in girls. Percentages of high blood lead levels (>6 μg/dL) were significantly higher in boys than girls in both years (1995: 77.5% and 51.9%, respectively; 2007: 32.6% and 16.5%, respectively), and declined significantly between 1995 and 2007 in both genders. Blood lead levels decreased over the interval of 12 years in school children resident in the Legnica-Głogow Copper Mining District.
Deposition rates of atmospheric particles were determined using previously published ²¹⁰Pb data in soils and air. The dry deposition velocities for moorland and woodland soils were 2.2±1.8 and 9±2 mm・s⁻¹, respectively. The ²¹⁰Pb concentration in rain was calculated to be 94±10 mBq・L⁻¹. The large (~4 times) deposition velocities in woodland relative to moorland soils is an indication of the degree of accumulation of particles, and most possibly contaminants within woodland soils, which is of practical importance in the mitigation of pollutant concentrations in urban areas by planting trees.
The objective of our study was to investigate the activity of selected soil enzymes (dehydrogenases, phosphatases, urease, and protease), as well as cadmium and lead concentrations, in soils and vegetables from gardening allotments in areas exposed to industrial contamination and from areas of similar physiographic conditions but that were not exposed to the direct impact of industrial emissions. Investigations comprised eight gardening allotments situated in the area of Upper Silesia (Miasteczko Śląskie, Zabrze) and in cities in eastern Poland (Lublin, Stalowa Wola). Strong correlations were demonstrated between cadmium and lead concentrations in the soil and root systems of analyzed plants (red beet, carrot, parsley). The observed high inactivation of the examined enzymes in soils exposed to strong anthropogenic influence (the area of Upper Silesia) confirms that soil environment contamination with Cd and Pb reached levels that threaten living organisms.
Landscape plantations are significantly water demanding in many parts of the world, particularly in dry regions. Adequate water supply is the main limiting factor behind landscape development, maintenance and beauty in such environments. On the other hand, monitoring the growth response of ornamental and landscape plants to irrigation water containing heavy metals can be useful in management and application of municipal wastewaters to these plantations instead of application in edible vegetable crops production, which is common in many urban areas. In the present study, one year old seedlings of Judas tree (Cercis siliquastrum) were irrigated for two years with water containing 0, 15 or 30 mg L–1 of lead (Pb) in absence or presence of cadmium (0 or 5 mg L–1) in a factorial design, and under greenhouse conditions. Heavy metal treatments had no significant effect on leaf SPAD value; however, plants treated with Pb15Cd0 combination had significantly higher SPAD value than Pb30Cd5 combination that showed the lowest leaf SPAD value. Increasing the lead and cadmium levels of irrigation water increased the number of chlorotic and necrotic leaves of plant than control, whereas it reduced the average leaf area and new shoot growth. The control plants or plants treated with lower level of heavy metals showed the highest leaf area and new shoot growth. Leaf photosynthesis rate was significantly reduced in all heavy metal treated plants than control plants, as the lowest amount was in Pb30Cd5 combination treatment. All heavy metal treatments showed higher leaf soluble carbohydrates and proline content than in control plants. Leaf soluble carbohydrates were highest in Pb30Cd0 and Pb30Cd5 treatments, and leaf proline was highest in Pb30Cd5 and Pb15Cd5 treatments. The results indicate that Judas tree is a relatively tolerant species to high concentrations of Pb and Cd in root medium added through the irrigation water, and long term dual application of these heavy metals can have additive harmful effects on plant growth.
This research assesses the concentration of Zn, Ag, Hg, Pb and Cu in surface water Kutcheri’s River Yankuzau and other streams coordinates range between longitude 11°48′ N to 11°53′N and latitude 7°00′ to 7°05′E using Atomic Absorption Spectrophotometre (AAS). Artisanal mining has become prominent in these areas. It’s become imperative to analyze these metal concentrations because they are associated with gold mineralization. Apart from polluting the water by artisanal miners, heavy metals are released into the surface water which most villager drink without pretreatment.
The Bahia Blanca Estuary includes a large tidal plain with an area close to 1150 km2.Mud is predominant in its sediments, where a significant population of the crab Chasmagnathus granulata lives during the whole year.Mo reover, there are important urban and industrial discharges into this environment. Cd and Pb concentrations were determined in samples of water (for both dissolved and suspended particulate matter) and surface sediments (total and <63 μm fractions).Or ganic matter was analysed in the sediments, while temperature, salinity, pH and dissolved oxygen were measured in the estuarine water The metal concentrations determined in this study were: 1.47 ± 1.08 μg Cd g−1 and 14.68 ± 4.31 μg Pb g−1 in surface sediments; 2.21 ± 1.33 μg Cd g−1 and 25.70 ± 7.09 μg Pb g−1 in the <63 μm sediment fraction; 0.18 ± 0.11 μg Cd g−1 and below the analytical detection limit of Pb in suspended particulate matter. Furthermore, dissolved Cd and Pb were lower than the norms for marine and estuarine waters (2 μg dm−3 for Cd and 5 μg dm−3 for Pb, E.P.A.). Simultaneously, the effects of Cd and Pb were studied on recently hatched larvae of Ch. granulata, through 96-hour semi-static acute assays.Via bility was the criterion assessed in the assays.LC 50 (96 h) for Cd was 46.43 μg dm−3 (36.92 − 56.34 μg dm−3), whilst that for Pb was 1. 0 mg dm−3 (0.79 − 1.23 mg dm−3), which demonstrates that Cd is more toxic towards larvae.F inally, both LC50 values determined for Cd and Pb were higher than the corresponding metal concentrations measured in the Bah´ıa Blanca environment.
This study addresses what underlies the high tolerance of some plant species to lead. The tolerance to lead of six species differing in their water requirements (xerophytes, mesophytes and hydrophytes) was determined. Seedlings were treated with lead (2.5 mg/dm3 Pb2+ from PbCl2) for 8 days in a hydroponic culture. Tolerance to lead (on the basis of root growth, i.e., index of tolerance), lead concentration in tissues and lead transport to stems (using AAS) were studied. The presence of lead in organs, tissues and cells was determined by the rhodizonate method. Using the results, we classified the tested plant species according to lead tolerance, in the following order: Berteroa incana < Helichrysum sp. < Leontodón hispidus < Cucumus sativus < Dianthus carthusianorum < Rumex aquaticus. The lead tolerance of these species correlated with their water requirements. Plants from dry stands demonstrated the lowest tolerance to lead (Berteroa incana IT = 10%, Helichrysum sp. IT = 15%), those from damp stands had higher tolerance, and those from wet stands had the highest (Rumex aquaticus IT = 60%). This dependence was corroborated by field observations showing that mesophyte species dominate calamine waste heaps (55%) despite the drought conditions and strong insolation that prevail there.
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