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1.
In this study, our aim was to determine the common sources of origin of 18 elements in the livers of Common Buzzards collected during the breeding season in an extensive agricultural landscape in south-east Poland with respect to age (adults and immatures) and sex (males and females). In all 34 specimens collected, the element concentrations followed the pattern of S > Na > Fe > Mg > Zn > Si > Cu > Mn > Ba > Se > B > Pb > Hg > Cd > Cr > Ni > Sr > V. Among the heavy metals examined, only the concentration of Pb was relatively high. Given the prevalence of farmland in the studied area (and the wide use of fertilizers), common use of lead-hunting ammunition and moderate concentration of Pb in fertilizers, the indirect influence of hunting ammunition ingested with food or as gastroliths was apparently responsible for the elevated levels of Pb in the livers of Common Buzzards. In our study, no significant sex-related differences were detected in the hepatic concentrations of any element. However, a significant age effect was observed for three elements, which had elevated levels in adults (Hg) and immature birds (B, Pb), and a significant age x sex interaction was found for S and Fe. These results might be explained by the importance of these elements in bone growth in immature birds (B), variable strategies of foraging between adults and immature birds (Pb), and possible intersex differences in the immature cohort in response to the presence of lead (S, Fe).  相似文献   

2.
The San Francisco Bay estuary isused by over one million shorebirds during springmigration and is home to several hundred thousandduring the winter. Most shorebird use occurs in thesouthern reach of the estuary (South Bay). Thereduced water circulation and discharge fromindustrial sources in the South Bay are responsiblefor the highest levels of some trace elements in theestuary. Wintering shorebirds have been found to havestrong site fidelity to areas as small as a fewkilometers in the South Bay, which may increase theirexposure to contaminants near local point sources. Inaddition, different shorebird species foraging at thesame site have been shown to have differentcontaminant burdens. Thus, our objectives were totest whether contaminant burdens differed by species,or whether contaminant burdens differed in shorebirdscollected at adjacent sites. We examined thecontaminant profiles of two species of shorebirds,long-billed dowitchers (Limnodromus scolopaceus)and western sandpipers (Calidris mauri) thatforage together at two sites, Hayward and Newark,separated by 8 km in the South Bay. We usedmultivariate analysis of variance tests to compare thecomposition of 14 elemental analytes in their livertissues and estimated their molar ratios of Hg and Se. Composite samples were used for contaminant analysesbecause of the small body size of the shorebirds. Seven elemental analytes (Ag, Ba, Be, Cr, Ni, Pb, V)were below detection limits in a majority of thesamples so statistical analyses were precluded. Inthe measurable analytes (As, Cd, Cu, Hg, Mn, Se, Zn),we found no significant intra-site differences ofcontaminant profiles for the two species. We pooledthe samples to examine inter-site differences andfound significant differences in contaminant profilesbetween shorebirds at the neighboring sites (P = 0.03). Shorebirds at Newark had higher (P < 0.05) concentrations of As, Cd, and Se than those at Hayward. Dowitchers at Newark had concentrations of Hg and Se which were highly correlated (P < 0.003) in a mean molar ratio of 1:19, similar tothat reported in other birds. In the larger dowitcherspecies, we also examined exposure to 20organochlorine compounds. Organic analyses showedthat the dowitchers had been exposed to DDE, PCBs,dieldrin and trans-nonachlor, but with no significantdifferences in concentrations between Hayward andNewark (P > 0.05).  相似文献   

3.
Willets (Catoptrophorus semipalmatus) were collected in June and August 1986 at the outlets of two agricultural drainages into the Lower Laguna Madre of South Texas and at two other Texas coastal sites. Mean liver concentration of arsenic was higher in August than June. Over 20% of the livers had arsenic concentrations elevated above a suggested background level of 5.0 ppm dry weight (DW), but concentrations (maximum 15 ppm) were below those associated with acute toxicity. Selenium concentration in livers varied from 2.3 to 8.3 ppm DW for all locations and represented background levels. Mercury concentrations in livers for all locations (means = 2.0 to 3.4, maximum 17 ppm DW) were below those associated with avian mortality and similar to levels found in other estuarine/marine birds. DDE in carcasses was higher in adults (mean = 1.0 ppm wet weight) than juveniles (0.2 ppm), and higher in August (1.0 ppm) than June (0.5 ppm); however, DDE concentrations were generally at background levels. Based on brain cholinesterase activity, willets were not recently exposed to organophosphate pesticides.  相似文献   

4.
Canadian shorebirds are exposed to environmental contaminants throughout their annual cycle. Contaminant exposure among species varies with diet, foraging behaviour and migration patterns. We sampled twelve species of shorebirds from four locations across Canada to assess their exposure to PCBs, organochlorine pesticides, as well as four trace elements (Hg, Se, Cd, As). SigmaPCB and SigmaDDT followed by SigmaCHL were most frequently found above trace level in the shorebird carcasses. In general, the plover species (American golden, semipalmated, black-bellied) appear to be the most contaminated with organochlorines, whereas Hudsonian and marbled godwits appear to be the least contaminated. Among adult birds, the greater and lesser yellowlegs had the highest hepatic Hg concentrations (2.4-2.7 microg g(-1) dw), whereas American golden plovers as well as Hudsonian and marbled godwits contained relatively low levels of Hg (<1 microg g(-1) dw). Renal Se concentrations varied from 3.2 to 16.7 microg g(-1) dw and exhibited little interspecific or seasonal variation. Renal Cd levels in adult birds were highest in Hudsonian godwits from Quill Lakes (43 microg g(-1) dw) and Cape Churchill (12 microg g(-1) dw), and lowest (0.8-1.5 microg g(-1) dw) in greater and lesser yellowlegs from Cape Churchill and Bay of Fundy. Renal As concentrations varied from 0.06 microg g(-1) dw in golden plovers from Cape Churchill to 4.6 and 5.1 microg g(-1) dw in dunlin samples from the Pacific coast. There is no evidence that contaminants were adversely affecting the shorebirds sampled from the Canadian locations in this study.  相似文献   

5.
Spatial trends and comparative changes in time of selected trace elements were studied in liver tissue from polar bears from ten different subpopulation locations in Alaska, Canadian Arctic and East Greenland. For nine of the trace elements (As, Cd, Cu, Hg, Mn, Pb, Rb, Se and Zn) spatial trends were investigated in 136 specimens sampled during 2005-2008 from bears from these ten subpopulations. Concentrations of Hg, Se and As were highest in the (northern and southern) Beaufort Sea area and lowest in (western and southern) Hudson Bay area and Chukchi/Bering Sea. In contrast, concentrations of Cd showed an increasing trend from east to west. Minor or no spatial trends were observed for Cu, Mn, Rb and Zn. Spatial trends were in agreement with previous studies, possibly explained by natural phenomena. To assess temporal changes of Cd, Hg, Se and Zn concentrations during the last decades, we compared our results to previously published data. These time comparisons suggested recent Hg increase in East Greenland polar bears. This may be related to Hg emissions and/or climate-induced changes in Hg cycles or changes in the polar bear food web related to global warming. Also, Hg:Se molar ratio has increased in East Greenland polar bears, which suggests there may be an increased risk for Hg(2+)-mediated toxicity. Since the underlying reasons for spatial trends or changes in time of trace elements in the Arctic are still largely unknown, future studies should focus on the role of changing climate and trace metal emissions on geographical and temporal trends of trace elements.  相似文献   

6.
Concentrations of Hg and Se were determined for a total of 125Common Loon (Gavia immer) eggs collected from lakes in Alberta, Saskatchewan, Ontario, Quebec, New Brunswick and NovaScotia, Canada between 1972 and 1997. Resulting data were compared to Hg and/or Se concentrations known or suspected tocause reproductive impairment in birds. Organic (methyl) Hg analyses were also performed on a subset of 24 loon eggs. Thirty-nine of 125 eggs had total Hg levels exceeding those (0.6 g g-1 ww, or 2.5 g g-1 dw)previously reported to be associated with reproductive impairment in common loons (Barr, 1986), and 9 of 125 eggshad Hg concentrations higher than the level associated withreproductive impairment in birds generally 1 g g-1 ww; (Thompson, 1996). Selenium concentrations in loon egg samples were less than levels known to cause reproductiveimpairment in birds. A weak but significant positive correlation was observed between egg-Hg and -Se concentrations(r = 0.511, p < 0.05). On average, methylmercury accounted for about 87% of total Hg in 24 eggs analysed for both total and organic Hg. In this subset of eggs, the relationship between organic (methyl) Hg and Se was significant (r = 0.538, p = 0.007) while that found between inorganic Hg and Se in the same eggs was not significant (r = 0.353, p = 0.091). This relationship was unexpected and was contrary to relationships established for organic and inorganic Hg vs. Se in adult loon liver and kidney tissue (Scheuhammer et al., 1998b).  相似文献   

7.
Forty-two soil and apple samples from central Greece were collected and analyzed with regards to the content in major (Ca, Fe, K, Mg, Na, P, and S) and trace elements (As, B, Ba, Cd, Co, Cr, Cu, Hg, Mn, Mo, Ni, Pb, Sb, Sc, Se, Sr, Ti, and Zn). Soil samples were analyzed by inductively coupled plasma atomic emission spectrometry, while for the apples inductively coupled plasma mass spectrometry was implemented. Several elements such as As, B, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Se, Ti, and Zn, represent high concentrations in apples from the study area. These relatively high concentrations may be a consequence of the local geology, along with the excessive application of agricultural products such as fertilizers and agrochemicals.  相似文献   

8.
The objectives of this study were to determine levels of heavy metal in the feathers and blood of Black-tailed gulls (Larus crassirostris), to evaluate metallothionein (MT) mRNA level in Black-tailed gulls on three independent islets, and to examine the correlation between heavy metal concentrations and MT mRNA expression. Eleven heavy metals (Al, Cd, Mn, Pb, Cr, Fe, Cu, Zn, Se, Hg, and As) were investigated in blood and feathers of 65 chicks from breeding colonies (Seomando, Hongdo, and Dokdo islet) of South Korea in 2010. Heavy metals were assayed by PerkinElmer NexION 300 inductively coupled plasma mass spectrometry. The mean concentrations of non-essential heavy metals were found to blood containing Cd (0.002?~?0.02 ppm), Pb (0.06?~?0.18) ppm, Hg (0.03?~?0.05) ppm, and As (0.26?~?0.48 ppm), and feather containing Cd (0.05?~?0.30 ppm), Pb (2.47?~?10.80 ppm), Hg (1.18?~?1.57 ppm), and As (0.15?~?0.44 ppm). Chicks on Seomando islet showed the highest levels of metals (Cd, Pb, Mn, Cr, Cu, and Se in blood; Al, As, Mn, Cr, Fe, Cu, and Se in feathers) among the colonies. Concentrations of Pb and Hg in feathers were the highest on Hongdo, and the levels of Cd and Zn in feathers were the highest on Dokdo islet. MT mRNA in the blood of Black-tailed gulls was relatively higher in gulls from Seomando than in gulls from Hongdo and Dokdo islet. MT mRNA level is thus positively correlated to heavy metal concentrations in Black-tailed gulls.  相似文献   

9.
Concentrations of toxic heavy metals (cadmium (Cd), lead (Pb)) and major nutritional and trace elements (Ca, Mg, P, Cu, Fe, Mn, Se, Zn) were analyzed in the milk of Simmental (n?=?20) and Holstein-Friesian (n?=?20) cows from an organic farm. Elements were determined using inductively coupled plasma emission atomic spectrometry. The conducted research showed that the milk of Simmental cows was characterized by the more advantageous mineral composition and lower concentration of noxious heavy metals compared to the milk of Holstein-Friesian cows. In the milk of Simmental cows, significantly lower concentrations of Pb and Cd (P?<?0.001) and Cu (P?<?0.05) and significantly higher concentrations of Fe and Mg (P?<?0.05) as well as nonsignificantly higher concentrations of Ca, Mn, and Se were found. In the milk of both breeds, very low Cu concentrations were recorded. The higher-than-recommended concentration of Pb in milk was also found. In the milk of both breeds, the significant positive correlations between concentrations of the following elements were observed: Pb–Cd, Pb–Se, Cd–Se, Cd–Mn, Zn–Cu, Zn–P, Ca–P, Ca–Mg, and Mg–P. The correlations between other elements within each of the analyzed breeds separately were also found.  相似文献   

10.
The chemical form of Ag in the livers of five species of marine mammals was examined using X-ray absorption fine structure (XAFS) and X-ray fluorescence (XRF) spectroscopies. The XAFS analysis suggested that Ag(2)Se was present in the livers of the Franciscana dolphin (Pontoporia blainvillei), Dall's porpoise (Phocoenoides dalli), and Baird's beaked whale (Berardius bairdii), whereas Ag(2)S was present in the livers of the striped dolphin (Stenella coeruleoalba) and pygmy killer whale (Feresa attenuata). XRF spectroscopy results revealed that the distribution patterns of Ag and Se in a thin section of the liver of the Franciscana dolphin were the same; this also implied that Ag was associated with Se in the liver. Thus, the interaction of Ag with Se or S may offer significant protection against the toxicity of Ag in marine mammals. The formation of either Ag(2)Se or Ag(2)S might depend on the Hg levels in the liver. Ag(2)Se was observed in liver samples with relatively high Ag/Hg ratio, whereas liver samples with low Ag/Hg ratio contained Ag(2)S.  相似文献   

11.
Surface sediments collected from nine stations in Nemrut Bay, Aegean Sea were analyzed for trace metals (Hg, Cd, Pb, Cr, Cu, Zn, Mn, Ni, Fe, As, and Mg) and grain sizes. The results were compared with the numerical sediment guidelines used in North America as well as literature values reported for similar studies conducted in Izmit Bay and Izmir Bay. The metal levels were also evaluated according to the enrichment factor and contamination factor analyses. The analyses revealed significant anthropogenic pollution of Hg, Pb, Zn, and As in the surficial sediments of Nemrut Bay.  相似文献   

12.
The objective of this study was to investigate changes in the levels of toxic and essential elements in maternal blood during pregnancy and subsequently. A subset of 211 pregnant women from the North Norwegian Mother-and-Child Study was included. Blood samples were collected during the 2(nd) trimester (P1) and postpartum (day 3, P2; and 6 weeks, P3) in different regions of northern Norway, and were analyzed for a suite of 10 selected elements. The latter feature three general but distinct concentration patterns across the three collection periods, namely: progressive increase [Group 1: As, Cd (non-smokers only), Mn, Pb and Zn]; V-shaped, with a minimum at P2 [Group 2: Cd (smokers), Hg, Mo and Se]; and downward V, with a maximum at P2 [Group 3: Co and Cu]. These trends are interpreted in the context of underlying metabolic, hematological and physiological changes that occur in mothers, as well the biochemistry and accumulation preferences of these elements within the whole blood compartment and breast milk. Implications for biomonitoring strategies are discussed. In a multivariable analysis of the P1 data, fish consumption was a robust positive predictor for Hg (p < 0.02), As (p < 0.01) and Se (p ≤ 0.001) blood concentrations, multivitamin intake for Se (p < 0.001), and parity for Co (p < 0.002); age reached significance only for Hg (p < 0.001). An inverse association was observed between parity and Hg (p < 0.05). For the other elements, predictor patterns were not evident.  相似文献   

13.
Concentrations of ten heavy elements (Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn), as well as the pH values, organic matter contents, and electrical conductivities were measured in the surface soil samples collected from 21 sites of urban areas in the city of Novi Sad, the second largest city in Serbia, its suburban settlement and the nearby villages. Range of the heavy element concentrations was from 0.16 mg/kg (for Hg) to 18,994 mg/kg (for Fe). Significantly higher Hg and Mn concentrations were observed in subgroups with rural and market garden samples in comparison to the subgroups with urban and grassland samples, respectively, while the contents of Pb found in the grasslands subgroup were significantly higher than in the subgroup with market garden soils. Only one sample of urban soil exceeded the maximum permissible value for Zn set by the relevant Serbian legislation. According to the Dutch soil quality standard, the Cd and Co concentrations in majority of the examined soils were higher than the target values for unpolluted soil. The content of Hg was above the target value in 52% of the samples, most of them belonging to the subgroup of market garden soils. The results for the Novi Sad city area were compared to the relevant data available for other cities in the Western Balkan Countries. Principal component analysis of data revealed seven outlying samples, while the rest of the analyzed samples were grouped together indicating similar heavy element patterns most probably due to mixed emission sources.  相似文献   

14.
This paper presents and discusses the levels and temporal trends of concentrations of Cd, Pb, Hg, Cu, Zn, and As in livers and Hg in the muscle tissues of cod (Gadus morhua L) from the Baltic Sea during the period 1994–2010. Concentrations of Pb, Hg, and Cd exhibited significant downward trends. Cu and Zn concentrations exhibited upward trends in the period 1994 to 2010. No trends were detected for concentrations of As. The temporal trends identified in heavy metal concentrations in cod livers corresponded to the directions of changes in concentrations of these elements introduced into the Baltic Sea via river runoff and atmospheric emission, and those in surface and deep waters of the Baltic. Downward trends in the concentrations of toxic metals in cod livers suggest that advantageous changes are occurring in concentrations of heavy metals in the environment of the southern Baltic Sea.  相似文献   

15.
The sea bream??s nematode and Sparus aurata, sampled from the Iskenderun Bay, Mediterranean, in March 2008 were analyzed by inductively coupled plasma?Catomic emission spectrometry for their some heavy metal (Cd, Cr, Cu, Fe, Hg, Mn, Mg, Pb, and Zn) levels. The metal concentrations of the parasites were compared to different organs (liver, muscle, gill, intestine, and skin) of the fish hosts. There were significant differences in Cd, Cr, Cu, Fe, Mn, Zn, Hg, Mg, and Pb concentrations in tissues of fish and its parasite. The parasite Cd, Cu, and Pb concentration was higher than the other tissues. Furthermore, significant differences were detected in the heavy metal accumulations between the parasitized and unparasitized fish tissues in Cd, Cu, Hg, and Pb concentrations. The Cd, Hg, and Pb concentrations were found in fish muscle at mean concentrations over the permissible limits proposed by the Food and Agriculture Organization.  相似文献   

16.
Tissue levels of mercury (Hg; total, organic) and selenium (Se) were assessed in juvenile lemon sharks (Negaprion brevirostris) from Florida nearshore waters collected during a harmful algal bloom (HAB, brevetoxin) event and compared with sharks not exposed to HABs. In all sharks studied, total Hg levels in the muscle were generally present in a molar excess over Se (which may protect against Hg toxicity) and mean muscle Hg levels (0.34  $\upmu $ g/g) exceed safe human consumption guidelines. While there was generally no difference in tissue Hg and Se levels following exposure of sharks to HABs, hepatic Hg levels were significantly lower (56% reduction) in the HAB-exposed sharks compared to controls. As Hg and HABs are globally increasing in scope and magnitude, further work is warranted to assess their interactions and biotic impacts within aquatic ecosystems, especially for a species such as the lemon shark that is classified as a near-threatened species by the International Union for the Conservation of Nature.  相似文献   

17.
Concentrations of organochlorine pesticides (DDTs, HCHs, and chlordanes), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), polycyclic aromatic hydrocarbons (PAHs), perfluorinated compounds (PFCs), and 20 trace elements were determined in livers of 3- to 5-year old stranded sea otters collected from the coastal waters of California, Washington, and Alaska (USA) and from Kamchatka (Russia). Concentrations of organochlorine pesticides, PCBs, and PBDEs were high in sea otters collected from the California coast. Concentrations of DDTs were 10-fold higher in California sea otters than in otters from other locations; PCB concentrations were 5-fold higher, and PBDE concentrations were 2-fold higher, in California sea otters than in otters from other locations. Concentrations of PAHs were higher in sea otters from Prince William Sound than in sea otters from other locations. Concentrations of several trace elements were elevated in sea otters collected from California and Prince William Sound. Elevated concentrations of Mn and Zn in sea otters from California and Prince William Sound were indicative of oxidative stress-related injuries in these two populations. Concentrations of all of the target compounds, including trace elements, that were analyzed in sea otters from Kamchatka were lower than those found from the US coastal locations.  相似文献   

18.
Metal concentrations were determined in surface sediments and transplanted mussels in a shallow semi-enclosed bay, Pagassitikos Gulf, Aegean Sea. Cu, Zn, Pb, Hg, and As levels in sediments were enriched close to point sources of pollution, i.e., Volos Port and cement plant. Fe, Mn, Cr, and Ni spatial distributions in sediments were rather uniform with increasing concentrations towards deeper sites, suggesting natural enrichment, whereas levels found in the port, although elevated, were not the highest in the study area. Spatial variations in concentrations of most metals in mussels transplanted nearshore were generally in accordance to those in sediments, with the highest Fe, Mn, Cr, Ni, and Cu levels in the port and the highest Hg levels close to the cement plant. Concentrations of metals in sediments and transplanted mussels were comparable to those reported in Mediterranean areas. Results indicate that pollution point sources contribute to anthropogenic metal enrichment in the study area.  相似文献   

19.
Statistical analysis of heavy metal concentrations in sediment was studied to understand the interrelationship between different parameters and also to identify probable source component in order to explain the pollution status of selected estuaries. Concentrations of heavy metals (Cu, Zn, Cd, Fe, Pb, Cr, Hg and Mn) were analyzed in sediments from Juru and Jejawi Estuaries in Malaysia with ten sampling points of each estuary. The results of multivariate statistical techniques showed that the two regions have different characteristics in terms of heavy metals selected and indicates that each region receives pollution from different sources. The results also showed that Fe, Mn, Cd, Hg, and Cu are responsible for large spatial variations explaining 51.15% of the total variance, whilst Zn and Pb explain only 18.93 of the total variance. This study illustrates the usefulness of multivariate statistical techniques for evaluation and interpretation of large complex data sets to get better information about the heavy metal concentrations and design of monitoring network.  相似文献   

20.
Earlier assessments have suggested that salmon farms may act as a source of mercury (Hg) and other elements in local marine environments. In this study, we measured 30 elements in the livers of demersal Atlantic cod (Gadus morhua) and pelagic saithe (Pollachius virens) caught in association with salmon farms (farm associated [FA]; n = 75) or at reference locations (control; n = 80) in three regions throughout the latitudinal extent of Norway (59-70° N). Concentrations of most elements (24 of 30) were higher (20-70%) in cod compared to saithe. In particular, Hg was 6.8 times higher in cod than saithe. Nine elements were significantly different between FA saithe and control saithe, but only four (Hg, U, Cr and Mn) were highest in FA saithe, and this pattern was only detected consistently across all locations for Hg. Thirteen elements differed in concentration between FA cod and control cod, but only three elements (U, Al and Ba) were higher in FA cod than controls, and this pattern was only detected consistently across all locations for Al. After controlling for a set of potentially confounding variables, the estimated concentrations of Hg in saithe livers were ~80% higher in FA fish compared to controls. In contrast, Hg concentrations were ~40% higher in control cod compared to FA cod. Our results do not support the notion that salmon farms in general increase the concentrations of potentially harmful elements in wild fish, and the distribution of Hg and other elements in cod and saithe in Norwegian coastal waters may be more influenced by habitat use, diet, geochemical conditions and water chemistry.  相似文献   

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