Heavy metals in three lakes in West Poland.

Concentrations of heavy metals (Ni, Cr, Co, Zn, Mn, Pb, Cd, Cu, Hg, Fe) as well as macronutrients (P, Ca, Mg) were measured in water, bottom sediments, and plants of three lakes in West Poland (southwest of Poznan). The plants collected were Nymphaea alba, Nuphar luteum, Ceratophyllum demersum, Phragmites communis, Typha latifolia, and Schoenoplectus lacustris. These plants contained elevated levels of Co, Zn, Pb, Cd, Cr, and Hg. Analyses of water and bottom sediments indicated that the lakes were polluted with Zn, Cd, Cu, and Pb and partly with Ni and Hg. Strong positive correlations were found between concentrations of Cd in water and in plants, between concentrations of Cd in bottom sediments and in plants, between concentrations of Cr in water and in plants, between concentrations of Cr in bottom sediments and in plants, and between concentrations of Fe in water and in plants, indicating the potential of plants for pollution monitoring for these metals. A negative correlation was found between biomass production and Pb and Mn content in water and Pb and Mn content in bottom sediments. Cr and Cd accumulated in plants at a higher rate from bottom sediments than from water. The accumulation rate of Fe in plant tissues was higher with an increase in Fe in water than with an increase in Fe in bottom sediments.     

Toxicity of eight metals to Malaysian freshwater midge larvae Chironomus javanus (Diptera, Chironomidae)

Fourth instars larvae of freshwater midge Chironomus javanus (Diptera, Chironomidae) were exposed for a 4-day period in laboratory conditions to a range of copper (Cu), cadmium (Cd), zinc (Zn), lead (Pb), nickel (Ni), iron (Fe), aluminium (Al) and manganese (Mn) concentrations. Mortality was assessed and median lethal concentrations (LC(50)) were calculated. LC(50) increased with the decrease in mean exposure times, for all metals. LC(50)s for 96 hours for Cu, Cd, Zn, Pb, Ni, Fe, Al and Mn were 0.17, 0.06, 5.57, 0.72, 5.32, 0.62, 1.43 and 5.27 mg/L, respectively. Metals bioconcentration in C. javanus increases with exposure to increasing concentrations and Cd was the most toxic to C. javanus, followed by Cu, Fe, Pb, Al, Mn, Zn and Ni (Cd > Cu > Fe > Pb > Al > Mn > Zn > Ni). Comparison of LC(50) values for metals for this species with those for other freshwater midges reveals that C. javanus is equally or more sensitive to metals than most other tested dipteran.     

Heavy Metal Accumulation in Lake Sediments, Fish (Oreochromis niloticus and Serranochromis thumbergi), and Crayfish (Cherax quadricarinatus) in Lake Itezhi-tezhi and Lake Kariba, Zambia

We measured the level of heavy metal accumulation in lake sediments, herbivorous (Oreochromis niloticus) and carnivorous (Serranochromis thumbergi) fish, and crayfish (Cherax quadricarinatus) from Lake Itezhi-tezhi (ITT) and Lake Kariba. We used atomic absorption spectrophotometry to quantify the levels of seven heavy metals (Cr, Co, Cu, Zn, Cd, Pb, and Ni). The sediment and the herbivorous fish O. niloticus accumulated a very high concentration of Cu in Lake ITT, most likely due to the discharge of Cu waste from a mining area 450 km upstream. The aquatic species we sampled in Lake Kariba had higher concentrations of Cr, Ni, and Pb relative to those in Lake ITT. This is most likely due to anthropogenic activities, such as the use of leaded petrol and antifouling agents in marine paints. Interestingly, we observed a negative correlation between the coefficient of condition (K) and Ni concentration in the crayfish hepatopancreas. Both O. niloticus and the crayfish had much higher biota-sediment accumulation factors (BSAF) for Cu, Zn, and Cd relative to Cr, Co, Pb, and Ni. The rank of BSAF values for O. niloticus (Cu > Cd > Zn) and C. quadricarinatus (Zn > Cd > Cu) differed from the expected ranks based on the general order of affinity of metals (Cd >> Zn > Cu).     

Copper and zinc contamination in oysters: subcellular distribution and detoxification

Metal pollution levels in estuarine and coastal environments have been widely reported, but few documented reports exist of severe contamination in specific environments. Here, we report on a metal-contaminated estuary in Fujian Province, China, in which blue oysters (Crassostrea hongkongensis) and green oysters (Crassostrea angulata) were discovered to be contaminated with Cu and other metals. Extraordinarily high metal concentrations were found in the oysters collected from the estuary. Comparison with historical data suggests that the estuary has recently been contaminated with Cr, Cu, Ni, and Zn. Metal concentrations in blue oysters were as high as 1.4 and 2.4% of whole-body tissue dry wt for Cu and Zn, respectively. Cellular debris was the main subcellular fraction binding the metals, but metal-rich granules were important for Cr, Ni, and Pb. With increasing Cu accumulation, its partitioning into the cytosolic proteins decreased. In contrast, metallothionein-like proteins increased their importance in binding with Zn as tissue concentrations of Zn increased. In the most severely contaminated oysters, only a negligible fraction of their Cu and Zn was bound with the metal-sensitive fraction, which may explain the survival of oysters in such contaminated environments.     

公路旁土壤中重金属污染分布及潜在生态危害的研究

[目的]研究公路旁土壤中重金属污染的分布及潜在生态危害。[方法]以319国道龙岩市新罗区路段为研究区,对耕作土采样,用原子吸收光谱法和分光光度法分析土壤中重金属Cd、Pb、Cu、Zn和Cr含量,并与对照区比较,同时采用Lars Hakanson指数法评价重金属的潜在生态危害。[结果]研究区表层土壤cd[(1.48±0.60)mg/kg]、Pb[(160.17±55.99)mg/kg]、cu[(38.44±12.16)mg/kg]、Zn[(80.35±6.60)mg/kg]、Cr[(79.50±23.58)mg/kg]含量显著高于对照区(P<0.001),Cd和Pb为重度污染(100％),Cu和Cr为轻微污染(分别占监测点位的55.8％和35.3％);土壤对重金属元素的吸收及污染程度:Pb>Cd>Cu>Cr>zn。潜在生态危害综合指数为253.0,主要污染为Cd,达到很强的生态危害,其次是Pb、Cu、Cr和Zn,均为轻微生态危害;潜在生态危害地带自公路起向其两侧扩散范围约为150 m。[结论]公路旁土壤中重金属以Cd、Pb污染为主,属于中等生态危害,污染物主要来源于机动车辆燃料和轮胎中所含微量重金属成分。     

Heavy Metal Concentrations in Marine Fishes Collected from Fish Culture Sites in Hong Kong

The levels of six heavy metals (Cd, Cr, Cu, Ni, Pb, and Zn) in different tissues of three species of cultured marine fishes (Epinephelus areolatus, Lutjanus russelli, and Sparus sarba) collected from three fish culture sites in Hong Kong were evaluated. Metal pollution problems in the fish culture sites were serious, as reflected by the high metal concentrations recorded in sea water, sediments, and the biomonitor Perna viridis. In general, tissues of all three species contained high concentrations of Zn and Cu, but much lower concentrations of Ni, Pb, Cd, and Cr. Similar pattern of heavy metal concentrations was observed in sea water, sediment, and P. viridis. Metal concentrations in various tissues varied greatly among species and among fish culture sites. Different tissues showed different capacity for accumulating heavy metals. Gonad of all three species contained high concentrations of Zn. On the other hand, liver seemed to be the primary organ for Cu accumulation. Overall, metal concentrations in the tissues of culture marine fishes were much lower than those in P. viridis. Despite high metal levels in sea water and sediments, concentrations of Cd, Cr, and Pb in edible tissues, including muscle and skin, did not exceed permissible levels recommended by the Hong Kong Government for human consumption. Received: 3 December 1999/Accepted: 13 June 2000     

Historical Characteristics of Contamination and Risk of Heavy Metals in Weishan Lake,China

Combined with the dating analysis of ²¹⁰Pb and ¹³⁷Cs, the historical concentration and risk of As, Cd, Cr, Cu, Hg, Ni, Pb and Zn in the core sediment of Weishan Lake were determined. Pollution concentrations, enrichment factor, geo-accumulation index, and ecological risk index of these metals and C/N ratio indicate that the natural inputs prevailed till early 1900s. From late 1970s onwards, the risk posed by these metals was significantly increased. Cu and Hg might cause adverse biological effects. The increase of soil erosion and wastewater discharge in the watershed promoted input and accumulation of these metals in the lake. The coal and petroleum industry in the catchment led the more accumulation of Hg, Cd and Cu in the lake.     

Appraisal of Heavy Metals in Groundwater in Chennai City Using a HPI Model

Heavy metal contamination in Chennai city was evaluated using a heavy metal pollution index (HPI) model in conjunction with the spatial distribution maps. Metals such as Cd, Cr, Cu, Pb and Zn in the groundwater were determined using standard methods and the resultant data was utilized in the development of a HPI model. The metal concentrations showed a dominance in the order of Zn > Cu > Cr > Pb > Cd respectively. About 14.3 % of the samples (n = 2), exhibited high HPI (>38) and the highest value, HPI = 97.55, has been recorded from Thiruvanmiyur area. Statistical analysis revealed a positive correlation between metals such as Cd and Cr (r = 0.606), Cd and Cu (r = 0.601), Cr and Cu (r = 0.464) and Pb and Zn (r = 0.416), suggested their common origin. The spatial distribution maps of heavy metals and the HPI suggested that the SW region, especially Adyar and Thiruvanmiyur regions are highly contaminated with the metals. Industrialisation and improper waste dumping were identified as the major cause for the accumulation of metals in the groundwater of Chennai city.     

Recent influxes of metals into Lake Pepin,a natural lake on the Upper Mississippi River

The recent chronology of metal deposition was examined in Lake Pepin, a large natural lake on the Upper Mississippi River about 75 km downstream from the Minneapolis-St. Paul, Minnesota, metropolitan area. The lake, which has a high trapping efficiency for suspended sediments, serves as a sink for metals from industrial and domestic effluents discharged into the river. Sediment cores collected in 1981 from seven locations in the lake were analyzed for Cd, Cr, Cu, Ni, Pb, Zn, and Al (a reference element). Dating of a core with¹³⁷Cs indicated that inputs of these metals increased markedly in the late 1950s, peaked in the early 1970s, and decreased in the late 1970s to 1981. Sediment enrichment factors decreased in the order Pb>Cd>CuCr>Zn>Ni. The depth of the most highly contaminated strata in the core profiles decreased longitudinally from upstream to downstream—paralleling the upstreamto-downstream decrease in sedimentation rates. Changes in metal inputs to the lake would be most readily detected by analysis of sediments from the uppermost reaches, but the potential for release of sediment-associated metals to the water column is probably greatest in downstream reaches.     

Comparison of heavy metals in marine sediments from coast areas in East and Southeast Asian countries during the years 2000--2010

Comparisons of heavy metals (Cd, Cr, Cu, Ni, Pb, and Zn) in marine sediments from coast areas in Southeast and East Asian countries during the years 2000-2010 are studied and discussed in this paper. The results indicate that the average compositions of Cd ranged from 0.13 to 0.89 mg/kg, and the average compositions of Cr ranged from 0.09 to 96.0 mg/kg. Moreover, the average compositions of Cu ranged from 3.00 to 148 mg/kg, and the average compositions of Ni ranged from 1.00 to 37.4 mg/kg. In addition, the average compositions of Pb ranged from 1.00 to 111 mg/kg. Finally, the average compositions of Zn ranged from 4.00 to 595 mg/kg. From the point of view of metals distribution areas for this study, the average highest metal of Ni occurred in East Asia, while the highest metals of Cd, Cr, Cu, Pb, and Zn occurred in Southeast Asian countries.     

Anthropogenic Sources of Heavy Metals in the Indian Ocean Coast of Kenya

Water and surface sediment samples from Rivers Sabaki, Ramisi and Vevesi that flow into the Indian Ocean coast of Kenya were analysed for heavy metals. The sediment concentrations of exchangeable cations (in μg/g) for Co, Cu, Mn, Ni, Pb, Sn and Zn ranged from 0.10 to 506.75 (for Mn at Sabaki), constituting between 2% and 20% of the total metal concentrations obtained by digestion with strong acid. Cu, Mn, Ni, Pb and Zn were more leachable with 0.1 N HCl. The total dissolved metal in water and the total sediment concentrations for Ag, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sn and Zn are given in the text. For dissolved metals, the metal/Mn ratios indicated higher concentrations of Ag in Sabaki River, Cd in Ramisi, Ni in Sabaki and Pb in Ramisi, respectively. In sediments, the metal/Mn ratios showed higher enrichment of Ag in Ramisi, Cd in Sabaki and Vevesi, and Zn in Sabaki, respectively. Enrichment factors showed elevated levels of Cd, Pb and Zn in sediment in River Sabaki and River Vevesi that were due to anthropogenic inputs through Athi River. The total dissolved metal concentration ranges for the three rivers were comparable with those ranges reported in rivers in South Africa but the sediment concentrations were below those of rivers in Europe and Asia where anthropogenic addition of some of the toxic elements such as Cu, Pb and Cd is evidently higher.     

Analysis of Heavy Metals in Water and Surface Sediment in Five Rift Valley Lakes in Kenya for Assessment of Recent Increase in Anthropogenic Activities

The concentrations of heavy metals Ag, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sn and Zn were analysed in water and surface sediments of five Rift Valley lakes Nakuru, Elementaita, Naivasha, Bogoria and Baringo in Kenya. The dissolved mean concentration levels (μg/L) in water ranged within 13.0–185.0 (Ag), 2.0–43.0 (Cd), 5.0–316.0 (Co), 25.0–188.0 (Cr), 4.7–100.0 (Cu), 50.0–282.0 (Mn), 19.0–288.0 (Ni), 25.0–563.0 (Pb), 300.0–1050.0 (Sn) and 29.0–235.0 (Zn). The mean sediment concentrations (in μg/g (dry weight)) ranged within 0.1–0.35 (Ag), 0.05–1.18 (Cd), 0.17–1.38 (Co), 1.94–4.91 (Cr), 1.46–20.95 (Cu), 667.7–3946.8 (Mn), 11.69–39.72 (Ni), 10.92–38.98 (Pb), 17.21–56.52 (Sn) and 96.2–229.6 (Zn). The data indicate that some of the sites analysed, especially in Lake Nakuru, had relatively higher concentration levels of heavy metals Cd, Co, Cu, Pb, Ni, and Zn in the water which points to anthropogenic addition. However, potential influence of geochemical processes on the concentration levels in sediment is also shown in Co, Ni, and Cu which were more concentrated in the remote Lake Baringo sediment as well as in Pb and Mn which were more concentrated in the remote Lake Bogoria sediment. Data on some important limnological parameters including pH, salinity, electrical conductivity and temperature are also presented.     

Heavy Metal Content of Potato Chips and Biscuits from Nagpur City, India

Heavy metals composition of foods is of immense interest because of its essential or toxic nature. In view of this, we determined concentrations of select heavy metals from food items such as, potato chips and biscuits that were obtained from Nagpur City, India. The present study revealed preferred digestion method for different heavy metal recovery. The accumulation trend for Potato chips was in following order Fe > Al > Zn > Ni > Cu > Mn > Co > Cr > Pb and Cd, while for Biscuits it was Al > Fe > Zn > Ni > Mn > Co > Cr > Pb > Cu and Cd.     

Accumulation of Heavy Metals in Different Body Tissues of Atlantic Salmon,Salmo salar L., Exposed to a Model Mixture (Cu,Zn, Ni,Cr, Pb,Cd) and Singly to Nickel,Chromium, and Lead

One-year-old Atlantic salmon smolts were exposed for 2 weeks either to six priority heavy metal mixture or to Ni, Pb, and Cr singly at a concentration corresponding to Lithuanian inland water standards: Cu – 0.01, Zn – 0.1, Ni – 0.01, Cr – 0.01, Cd – 0.005 and Pb – 0.005 mg/L, respectively under semi-static conditions. The presence of metal mixture in the water only partly (by 50 %) affected the accumulation of single metals in body tissues (muscle, gills, liver and kidneys) probably due to the synergistic interactions among metals. Although metal concentrations increased in most cases, only Pb exceeded recommended level for human consumption (0.2 Pb mg/L) by 1.1-fold to 2.1-fold.     

An Assessment of Heavy Metal Contamination in Vegetables Grown in Wastewater-Irrigated Areas of Titagarh,West Bengal,India

The effects of municipal wastewater irrigation on the accumulation of heavy metals (Pb, Zn, Cd, Cr, Cu and Ni) in soil and vegetables were investigated by monitoring wastewater-irrigated agricultural field of Titagarh, 24-Parganas (North), West Bengal, India. The mean concentrations of Pb, Ni, Cu in the irrigation water and the mean Cd content in soil were much above the recommended level. The concentrations of Pb, Zn, Cd, Cr and Ni in all the examined vegetables were beyond the safe limits. The study reveals that heavy metal-contaminated vegetables grown in wastewater-irrigated areas may pose public health hazards.     

Redistribution of Fractions of Zinc,Cadmium, Nickel,Copper, and Lead in Contaminated Calcareous Soils Treated with EDTA

Effect of ethylene diamine tetraacetic acid (EDTA) on the fractionation of zinc (Zn), cadmium (Cd), nickel (Ni), copper (Cu), and lead (Pb) in contaminated calcareous soils was investigated. Soil samples containing variable levels of contamination, from 105.9 to 5803 mg/kg Zn, from 2.2 to 1361 mg/kg Cd, from 31 to 64.0 mg/kg Ni, from 24 to 84 mg/kg Cu, and from 109 to 24,850 mg/kg Pb, were subjected to EDTA treatment at different dosages of 0, 1.0, and 2.0 g/kg. Metals in the incubated soils were fractionated after 5 months by a sequential extraction procedure, in which the metal fractions were experimentally defined as exchangeable (EXCH), carbonate (CARB), Mn oxide (MNO), Fe oxide (FEO), organic matter (OM), and residual (RES) fractions. In contaminated soils without EDTA addition, Zn, Ni, Cu, and Pb were predominately present in the RES fraction, up to 60.0%, 32.3%, 41.1%, and 36.8%, respectively. In general, with the EDTA addition, the EXCH and CARB fractions of these metals increased dramatically while the OM fraction decreased. The Zn, Ni, Cu, and Pb were distributed mostly in RES, OM, FEO, and CARB fractions in contaminated soils, but Cd was found predominately in the CARB, MNO, and RES fractions. The OM fraction decreased with increasing amounts of EDTA. In the contaminated soils, EDTA removed some Pb, Zn, Cu, and Ni from MNO, FEO, and OM fractions and redistributed them into CARB and EXCH fractions. Based on the relative percent in the EXCH and CARB fractions, the order of solubility was Cd > Pb > Ni > Cu > Zn for contaminated soils, before adding of EDTA, and after adding of EDTA, the order of solubility was Pb > Cd > Zn > Ni > Cu. The risk of groundwater contamination will increase after applying EDTA and it needed to be used very carefully.     

Toxicity of heavy metals using sperm cell and embryo toxicity bioassays with Paracentrotus lividus (Echinodermata: Echinoidea): comparisons with exposure concentrations in the Lagoon of Venice,Italy

Sperm cell and embryo toxicity tests using the Mediterranean sea urchin Paracentrotus lividus Lmk were performed to assess the toxicity of As3+, Cd2+, Cr3+, Ni2+, Pb2+, Cu2+, Zn2+, and Hg2+. The aim of this study was to improve information about the comparative sensitivity of sea urchin bioassays to the heavy metals, which are an important cause of contamination in the ecosystem of the Lagoon of Venice. Considering the data in mM/L, the order of toxicity is Hg2+ > Cu2+ > Zn2+ > As3+ > or = Cr3+ > or = Cd2+ > or = Pb2+ > or = Ni2+ for the sperm cell test and Hg2+ > or = Pb2+ > Cu2+ > Zn2+ > Cd2+ > Ni2+ > As3+ > or = Cr3+ for the embryo test. New toxicity data for metals expressed as median effective concentration (EC50) and no-observed-effect concentration (NOEC) are reported for the Mediterranean species. Accurate observations of embryotoxic effects at increasing metal concentrations were done, detecting some different behaviors in metal toxicity. Toxicity data compared with water column and pore-water concentrations recorded in the Lagoon of Venice (Italy) demonstrate the potential ability of bioassays using sea urchin to detect important contaminants in this ecosystem.     

公路交通对土壤重金属污染的研究

目的评价公路交通引起的土壤中重金属污染。方法选择320国道马龙路段进行耕作土采样,用原子吸收光谱法和分光光度法分析土壤中重金属Cu、Cd、Pb、Zn、Cr、As、Ni含量,采用清洁对照区土壤剖面重金属含量作为参比值,应用地积累指数法对重金属污染叠加进行评价。结果研究区土壤中Cu、CA、Pb、Zn、Cr、As、Ni的含量显著高于对照区（P〈0．01）。Cd为中等污染～强污染,Pb为中等污染,Cr和Cu为轻污染～中等污染。污染晕带沿公路延伸方向展开,自公路起向其两侧强度运渐减弱,扩散范围约为150m。土壤对重金属元素的吸收及污染程度;Cd〉Pb〉Cr〉Cu〉As〉Zn〉Ni。结论公路旁土壤重金属污染以Cd、Pb和Cr为主,污染叠加重金属来源主要为机动车燃料、轮胎、机械中所含微量重金属成分。     

Distribution of Metals in Surface Sediments from a Small River Flowing Through Urban and Agricultural Areas

The characteristic distributions of 12 metals (Al, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Cd and Pb) were investigated in surface sediments from a small river (Niitsu River) flowing through both urban and agricultural areas by comparison with those from the upper main stream (Nodai River). Among the investigated metals, the mean concentrations of Al, Cr, Fe, Zn, Cd and Pb in the Niitsu River were significantly higher than those in the Nodai River. The investigated sites can be characterized by the principal components 1–3.     

Trends in metals in urban and reference lake sediments across the United States, 1970 to 2001

Trends in metals concentrations in sediment cores from 35 reservoirs and lakes in urban and reference settings were analyzed to determine the effects of three decades of legislation, regulation, and changing demographics and industrial practices in the United States on concentrations of metals in the environment. Decreasing trends outnumber increasing trends for all seven metals analyzed (Cd, Cr, Cu, Pb, Hg, Ni, and Zn). The most consistent trends are for Pb and Cr: For Pb, 83% of the lakes have decreasing trends and 6% have increasing trends; for Cr, 54% of the lakes have decreasing trends and none have increasing trends. Mass accumulation rates of metals in cores, adjusted for background concentrations, decrease from the 1970s to the 1990s, with median changes ranging from -46% (Pb) to -3% (Hg and Zn). The largest decreases are from lakes in dense urban watersheds where the overall metals contamination in recently deposited sediments has decreased to one-half its 1970s median value. However, anthropogenic mass accumulation rates in dense urban lakes remain elevated over those in lakes in undeveloped watersheds, in some cases by as much as two orders of magnitude (Cr, Cu, and Zn), indicating that urban fluvial source signals can overwhelm those from regional atmospheric sources.