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1.
The concentrations of polycyclic aromatic hydrocarbons (PAHs) in Lates niloticus, Oreochromis niloticus and Rastrineobola argentea from three beaches were assessed to establish whether they are sources of human exposure in Kisumu Bay, Winam Gulf, Lake Victoria, Kenya. O. niloticus had 12 PAHs detected (TPAH 3.93 μg/kg); L. niloticus had 11 (TPAH 3.17 μg/kg). In both cases, the highest and lowest concentrations were Pyrene and Indeno(1,2,3-cd)pyrene, respectively, and the TPAHs were greater than the 2 μg/kg limit allowed by the European Commission although individually they were lower. R. argentea had 2 PAHs (TPAH 0.035 μg/kg). PAH pollution in the Winam Gulf, a potential source of exposure to human through contaminated fish, should be mitigated and safe management practices that reduce PAH levels should be adopted.  相似文献   

2.
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).  相似文献   

3.
In this study, the distribution and sources of inputs of trace metals including Cd, Cu, Zn and Pb from various sources as well as Fe which is widely used in the construction industry, into Winam Gulf of Lake Victoria were investigated. The sampling sites were located up streams and down streams of four rivers (Sio, Nyamasaria, Nyando and Sondu-Miriu), in four beaches along the lake (Port Victoria, Kisumu Car Wash, Dunga and Hippo point beaches) and in three estates (Nyamasaria, Migosi and Nyawita) in Kisumu city, covering potential agrochemical and industrial sources and drinking water points, respectively. The concentrations (in μg/L) of trace metals analysed in the lake and river waters ranged from <1.79 (Cd), <3.83 (Pb), <1.53–3.86 (Cu), 4.37–11.6 (Zn), 11.8–2,440 (Fe). The sediment concentrations (in μg/kg × 103) ranged from 0.19 to 1.91 (Cd), 6.86–138 (Pb), 18–100 (Cu), 36.2–443 (Zn) and 960–73,200 (Fe), with highest concentrations of all metals being recorded at Kisumu Car Wash area. The study confirmed that the concentrations of the metals accumulate downstream in the rivers both in water and sediment and these rivers are major sources of the heavy metal load into Winam Gulf of Lake Victoria.  相似文献   

4.
The ranges of concentrations of Cd, Cu, Pb and Zn of the soft tissues of C. corteziensis collected in seven coastal lagoons of NW Mexico were 1.55–7.45, 17.50–166.36, 4.13–9.49 and 245.34–2,304.12 μg/g (dry weight), respectively. Their distributions were not consistent and there were no seasonal trends, indicating different point sources of the metals in each lagoon. The mean Cd and Pb concentrations were 5.34 and 6.30 μg/g (dry weight), which are higher than the values indicative of polluted areas. Our data indicate that only the levels of Cd are a possible health risk in six of these lagoons, and only in the case of regular local consumers. In one, Cu and Zn reach levels of concern.  相似文献   

5.
Freshwater fish Oreochromis niloticus exposed to 0.05 μg/mL of Cu, Cd, Zn, Ag and Cr for up to 30 days. Only Ag, which exceeded environmentally realistic concentrations by a factor of >100 caused fish mortality within this period. Metals increased aspartate transaminase (AST) activity, while they decreased alanine transaminase (ALT) activity, except Cr exposure. Concentrations of free –SH group decreased whereas protein concentrations did not alter following metal exposures. Detectable metal accumulation occurred in the liver of Cd, Cu and Zn exposed fish. This study emphasized that both enzymatic and non-enzymatic mechanisms may be useful in understanding the degree of metal toxicity in fish liver.  相似文献   

6.
Concentrations of 11 metals (Cd, Cr, Cu, Fe, Mn, Pb, Zn, Na, K, Ca, and Mg) were assayed in the teeth of two populations of the Silesian region. The first group (n = 83) comprised the residents of Katowice–Szopienice, a town located in the center of the Upper Silesian industrial region, in close proximity to a Pb plant, whereas the other was a group of residents of the agricultural community Strumień (n = 44). The concentrations of all the trace metals were found to be higher in the teeth of Katowice–Szopienice residents. The methods of cluster analysis distinguished two clusters of metals in the teeth: essential (Ca, Na, Mg, Zn, and K) and trace (Cd, Mn, Cr, Cu, Fe, and Pb) elements. Euclidean distances reflected the differences in concentrations between the two groups. The results obtained were analyzed using principal component analysis. Four principal factors accounted for 68.1% of the total variance for Katowice–Szopienice residents and for 80.1% for Strumień residents. The first factor showed high contributions of Cu and Cr, elements present in humans as a result of diet, and also Mn for Katowice–Szopienice residents because of environmental contamination. The second factor was characterized by large Zn and Cd fractions and, for Katowice–Szopienice residents, Pb and K as well. The diversified exposure of both populations was reflected by the differences in Euclidean distances and contribution of particular elements with respect of principal components.  相似文献   

7.
The relationship between sex, size (length and weight) and metal concentrations in the tissues of two commercially valuable fish species (silver pomfret, Pampus argenteus and tiger tooth croaker, Otolithes ruber) from Persian Gulf were evaluated. Concentrations of the metals in fish species ranged as follows: Mn 0.743–11.279; Cd 0.175–2.375; Pb 2.406–11.297; Zn 10.837–80.389; Fe 2.263–86.110; Cu 1.503–6.333 μg/g dry weight, respectively. Metal content in both fish varied with type of metals, organ, and sex. Results showed that, except in a few cases, significant relationships between metal concentrations and fish size were negative.  相似文献   

8.
The muscles of some important marine fishes collected in and around Hooghly estuarine coastal areas were analyzed for the heavy metals Cu, Zn, Ni, Cd, Cr and Pb. The concentration range of Cu (16.22–47.97 ppm), Pb (12.40–19.96 ppm) and Zn (12.13–44.74 ppm) were recorded comparatively higher and were similar to that found in contaminated areas. On the other hand the ranges of Ni (2.20–3.69 ppm), Cr (0–3.89 ppm) and Cd (0.62–1.20 ppm) were almost equal to those carried out over a wide range of geographical areas. The degree of bioaccumulations was metal-specific as well as species-specific in nature. The toxic groups of metals (Pb and Cd) showed higher variability than the essential metals (Cu, Zn and Ni). The calculated intake value of metals (week−1 kg−1 body wt) varied from 14.88 to 27.60 of Pb, 0.87 to 1.68 of Cd, 0.0 to 5.45 of Cr, 22.70 to 137.16 of Cu, 3.08 to 5.17 of Ni and 16.98 to 62.60 of Zn through human consumption of these fishes and were compared with those of standard Provisional Tolerable Weekly Intake value (PTWI) per kg body weight as stipulated by WHO. The PTWICal values of Pb in some of the fishes recorded marginally excess values and may indicate a health risk through consumption of successive 7 days in a week.  相似文献   

9.
Metal accumulation in various tissues of Heteropneustes fossilis exposed to the effluent generated from an open cast coal mine was investigated. The contents of Fe, Mn, Cu, Zn, Ni, Pb, Cd and Cr in the effluent were above the permissible limits as suggested by the different pollution control agencies. Out of the eight metals investigated, accumulation (mg kg−1 dry weight of tissue) of Fe was maximum in every tissues followed by liver (265.88 ± 49.89) > kidney (153.0 ± 65.85) > gills (50.66 ± 23.923) > brain (49.303 ± 5.11) > air breathing organs (27.98 ± 10.93) > skin (19.56 ± 2.53) > muscles (8.74 ± 0.83). This was succeeded by Pb in brain (39.35 ± 5.79), Zn in kidneys (27.04 ± 2.31), Mn in the gills (20.69 ± 3.044), Cu (12.53 ± 1.01) > Cr (5.10 ± 2.87) in liver and Cd in kidneys (2.18 ± 0.084). Liver and ABOs showed significant uptake of all the metals. Except Cu and Cr, accumulation of most of the metals by kidneys and gills were also significant. Accumulation of Fe, Cd, Pb and Cr in most of the tissues of exposed fish were above the permissible limits indicating their potential hazardous impact on fish as well as on fish consumers. Even in the tissues of untreated fish the concentrations of Fe (12.26–428.47), Cd (0.2–1.22), Pb (0.02–9.42) and Cr (1.14–11.05) were above the permissible limits. This clearly demonstrates greater bioavailability of these metals in the area.  相似文献   

10.
To characterize the partitioning of metals in a stream ecosystem, concentrations of trace metals including As, Cd, Cu, Pb, and Zn were measured in water, colloids, sediment, biofilm (also referred to as aufwuchs), macroinvertebrates, and fish collected from the Boulder River watershed, Montana. Median concentrations of Cd, Cu, and Zn in water throughout the watershed exceeded the U.S. EPA acute and chronic criteria for protection of aquatic life. Concentrations of As, Cd, Cu, Pb, and Zn in sediment were sufficient in the tributaries to cause invertebrate toxicity. The concentrations of As, Cu, Cd, Pb, and Zn in invertebrates from lower Cataract Creek (63, 339, 59, 34, and 2,410 μg/g dry wt, respectively) were greater than the concentrations in invertebrates from the Clark Fork River watershed, Montana (19, 174, 2.3, 15, and 648 μg/g, respectively), that were associated with reduced survival, growth, and health of cutthroat trout fed diets composed of those invertebrates. Colloids and biofilm seem to play a critical role in the pathway of metals into the food chain and concentrations of As, Cu, Pb, and Zn in these two components are significantly correlated. We suggest that transfer of metals associated with Fe colloids to biological components of biofilm is an important pathway where metals associated with abiotic components are first available to biotic components. The significant correlations suggest that Cd, Cu, and Zn may move independently to biota (biofilm, invertebrates, or fish tissues) from water and sediment. The possibility exists that Cd, Cu, and Zn concentrations increase in fish tissues as a result of direct contact with water and sediment and indirect exposure through the food chain. However, uptake through the food chain to fish may be more important for As. Although As concentrations in colloids and biofilm were significantly correlated with As water concentrations, As concentrations in fish tissues were not correlated with water. The pathway for Pb into biological components seems to begin with sediment because concentrations of Pb in water were not significantly correlated with any other component and because concentrations of Pb in the water were often below detection limits.  相似文献   

11.
Surface sediments along the south of Caspian Sea were collected to evaluate the contamination of heavy metals. The result ranged (μg/g, Fe% dw): Pb(13.06–33.48); Ni(18.01–69.63); Cd(0.62–1.5); Zn(30.11–87.88); Cu(5.86–26.37) and Fe(1.8–4%) respectively. Cadmium showed higher EF when compared to other sites. Geoaccumulation Index value for Cd in most stations was classified as moderately contaminated and moderately to strongly contaminated, as well as the average of Igeo of Cd (1.77 ± 0.35) suggested that surface sediments of Caspian coast were moderately polluted by this metal. The result of the Pearson correlation showed that there were significant positive associations between Ni, Cd and Zn (r = 0.44–0.76; p < 0.01).  相似文献   

12.
The metal contents in tissues of fish species: M. cephalus, Diapterus sp., Scomberomorus sierra and Oreochromis aureus, were determined in order to evaluate if their consumption might become a health risk. The liver and gills of M. cephalus and Diapterus sp. had the highest values of Cu, Fe and Pb. In the muscle, there were no interspecific differences in the Cd, Cu and Pb contents (0.27–0.32, 0.96–1.30 and 2.12–2.80 μg/g dw, respectively). Cd and Pb may be of concern, since their mean contents in the edible muscle of the four species are higher than the limits of the European Community.  相似文献   

13.
In this study, it was aimed to determine accumulation of the metal concentrations in fish species in different regions which are Sürmene and Yomra bay at southeastern Black sea in Trabzon-Turkey. For this purpose, concentrations of metals (Cr, Co, Ni, Cu, Zn, As, Se, Cd, Sb, Hg, Pb) were measured by inductively coupled plasma mass spectrometry (ICP-MS) in muscle of red mullet (Mullus barbatus ponticus) and whiting (Merlangius merlangus euxinus). Metal concentrations were found for whiting ranged as follows; 0.35–1.64 (Cr), 0.01–0.09 (Co), 0.01–0.71 (Ni), 0.71–1.45 (Cu), 18.64–68.06 (Zn), 2.05–9.66 (As), 0.15–14.16 (Se), 0.01–0.22 (Cd), 0.01–0.01 (Sb), 0.01–0.15 (Hg), 0.01–0.25 (Pb) and for red mullet as 0.43–1.04 (Cr), 0.05–0.23 (Co), 0.02–0.67 (Ni), 0.74–2.32 (Cu), 19.89–43.50 (Zn), 6.04–24.82 (As), 0.02–9.83 (Se), 0.01–0.11 (Cd), 0.01–0.01 (Sb), 0.07–0.18 (Hg), 0.01–0.20 (Pb) μg g−1 dry weight. Metal concentrations in samples were found to be lower than legal limits proposed by Turkish Food Codex (2008), Food and Agricultural Organization (1983), and European Commission (Off J Eur Union L364-5–L364-24, 2006) for human consumption.  相似文献   

14.
In the Taxco mining area, sulfide mineral oxidation from inactive tailings impoundments and abandoned underground mines has produced acid mine drainage (AMD; pH 2.2–2.9) enriched in dissolved concentrations (mg l−1) sulfate, heavy metals, and arsenic (As): SO4 2− (pH 1470–5454), zinc (Zn; 3.0–859), iron (Fe; pH 5.5–504), copper (Cu; pH 0.7–16.3), cadmium (Cd; pH 0.3–6.7), lead (Pb; pH < 0.05–1.8), and As (pH < 0.002–0.6). Passive-treatment systems using limestone have been widely used to remediate AMD in many parts of the world. In limestone-treatment systems, calcite simultaneously plays the role of neutralizing and precipitating agent. However, the acid-neutralizing potential of limestone decreases when surfaces of the calcite particles become less reactive as they are progressively coated by metal precipitates. This study constitutes first-stage development of passive-treatment systems for treating AMD in the Taxco mine area using indigenous calcareous shale. This geologic material consists of a mixture of calcite, quartz, muscovite, albite, and montmorillonite. Results of batch leaching test indicate that calcareous shale significantly increased the pH (to values of 6.6–7.4) and decreased heavy metal and As concentrations in treated mine leachates. Calcareous shale had maximum removal efficiency (100%) for As, Pb, Cu, and Fe. The most mobile metals ions were Cd and Zn, and their average percentage removal was 87% and 89%, respectively. In this natural system (calcareous shale), calcite provides a source of alkalinity, whereas the surfaces of quartz and aluminosilicate minerals possibly serve as a preferred locus of deposition for metals, resulting in the neutralizing agent (calcite) beings less rapidly coated with the precipitating metals and therefore able to continue its neutralizing function for a longer time.  相似文献   

15.
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.  相似文献   

16.
The relationships between concentration and size in Paracentrotus lividus were studied for seven metals (Zn, Pb, Cd, Fe, Cr, Cu, and Ti). In the calcified body compartment, Zn concentrations showed inverse power relationships, while concentrations of Pb, Cd, and Cr increased as power functions of echinoid size; Fe, Cu, and Ti concentrations did not vary significantly with echinoid size. In the non-calcified body compartment of the echinoid, the concentrations of Zn, Pb, Fe, Cu, and Ti showed inverse power relationships, Cd concentrations increased linearly, and Cr concentrations did not show any significant relationship with echinoid body size. Most relationships were rather weak, except in the cases of Pb and Fe in the non-calcified compartment and Cd in the calcified compartment. The allometric relationships were affected by seasonal factor in the non-calcified compartment only. The results indicate that biomonitoring programs using P. lividus as an indicator of metal contamination must take into account both echinoid size and season as source of metal concentration variations.  相似文献   

17.
Trace metals (Cd, Cu, Ni, and Zn) concentrations were assessed in the sea turtle Lepidochelys olivacea from a nesting colony of Oaxaca, Mexico. Twenty-five female turtles were sampled, a total of 250 eggs were collected during the “arribada” event of the 2005–2006 season. Zn concentrations were highest in the yolk [72.3 ± 10.9 μg/g dry weight (dw)] and blood (58.4 ± 4.7 μg/g dw), whereas Ni concentrations were highest in the shell (48.5 ± 12.9 μg/g dw). The mean concentrations of Cu, and Cd in the analyzed tissues were lower than those reported in other sea turtle species. However, Zn and Ni concentrations in the yolk and shell, respectively, had the same distribution pattern observed at loggerhead and green turtles. On the basis of one nesting season, the maternal transfer and/or the excretion rates of trace metals via eggs-laying, estimated in terms of metal burdens in whole body, were 0.2, 7.8, 3.4, and 21.5% for Cd, Cu, Zn, and Ni, respectively.  相似文献   

18.
The water quality, habitats, and biota of streams in the upper Animas River watershed of Colorado, USA, are affected by metal contamination associated with acid drainage. We determined metal concentrations in components of the food web of the Animas River and its tributaries—periphyton (aufwuchs), benthic invertebrates, and livers of brook trout (Salvelinus fontinalis)—and evaluated pathways of metal exposure and hazards of metal toxicity to stream biota. Concentrations of the toxic metals cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) in periphyton, benthic invertebrates, and trout livers from one or more sites in the upper Animas River were significantly greater than those from reference sites. Periphyton from sites downstream from mixing zones of acid and neutral waters had elevated concentrations of aluminum (Al) and iron (Fe) reflecting deposition of colloidal Fe and Al oxides, and reduced algal biomass. Metal concentrations in benthic invertebrates reflected differences in feeding habits and body size among taxa, with greatest concentrations of Zn, Cu, and Cd in the small mayfly Rhithrogena, which feeds on periphyton, and greatest concentrations of Pb in the small stonefly Zapada, a detritivore. Concentrations of Zn and Pb decreased across each trophic linkage, whereas concentrations of Cu and Cd were similar across several trophic levels, suggesting that Cu and Cd were more efficiently transferred via dietary exposure. Concentrations of Cu in invertebrates and trout livers were more closely associated with impacts on trout populations and invertebrate communities than were concentrations of Zn, Cd, or Pb. Copper concentrations in livers of brook trout from the upper Animas River were substantially greater than background concentrations and approached levels associated with reduced brook trout populations in field studies and with toxic effects on other salmonids in laboratory studies. These results indicate that bioaccumulation and transfer of metals in stream food webs are significant components of metal exposure for stream biota of the upper Animas River watershed and suggest that chronic toxicity of Cu is an important factor limiting the distribution and abundance of brook trout populations in the watershed. Received: 4 April 2000/Accepted: 31 July 2000  相似文献   

19.
Characteristics of the spatial and temporal distributions of selected heavy metals (Cu, Zn, Cd, Pb and Hg) in Bohai Bay, north China was examined. Surface sediment samples from 15 sites were collected and analyzed for the selected metals with atomic absorption spectrometry (AAS) from the year of 1997–2007. Mean concentrations of metals in the 11-year period showed that Hg and Zn concentrations slightly fluctuated, while Cu, Cd and Pb concentrations in sediments varied with time. High levels of heavy metals occurred not only along the shoreline but also at some site in the inner part of the bay, suggesting the contamination sources of heavy metals from both terrestrial inputs and the atmospheric deposition. Compared with the environmental background values of selected heavy metals it indicated that anthropogenic activities influenced the sediment quality. The contamination factor \textCif {\text{C}}^{i}_{f} , which is used to evaluate the pollution of the environment, showed that the contamination by selected heavy metals was moderate. Cd, Zn and Pb were the main polluting elements in this area.  相似文献   

20.
The concentrations of selected metals such as Cd, Pb, Cu, Zn, Cr, Ni, Mn, and Fe were determined in liver, kidney, and muscle of harbor porpoise (Phocoena phocoena) from three geographical regions, i.e., the Baltic Sea and Danish and Greenland coastal waters. The concentrations of Cd in liver and kidney increased with age of the specimens analyzed. Significant interspatial variations in both hepatic and renal levels of Cd were also observed. Average hepatic levels of Cd in Baltic, Danish, and Greenland specimens were (age range) 0.05–0.09, 0.12–0.25, and 20.6–51.6 μg g−1 dry weight, respectively. Such values for renal Cd were as follows: 0.55–0.71, 0.14–1.84, and 0.55–94.3 μg g−1 dry weight. In contrast to Cd, concentrations of Cu in the liver and kidney of specimens from Baltic, Danish, and Greenland areas did not indicate such great interspatial variability. The average hepatic values amounted to (age range) 14.1–15.5, 22.1–63.6, and 16.3–25.9 μg g−1 dry weight, and kidney contained on the average 7.83–8.80, 11.7–16.2, and 11.1–15.7 μg Cu g−1 dry weight, respectively. The higher levels of hepatic and renal Cd in Greenland specimens than in Baltic ones could be explained by different food composition in the area studied. Baltic porpoises mainly feed on fish (cod, plaice) containing extremely low levels of muscle Cd, but an important diet component of Greenlandic individuals is squid, characterized by elevated levels of Cd. Received: 22 May 2001/Accepted: 11 November 2001  相似文献   

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