Cadmium, copper and zinc in octopuses from Kerguelen Islands, Southern Indian Ocean

 Concentrations of cadmium, copper and zinc were measured in 34 octopuses over a large range of size and weight, caught in the Kerguelen shelf waters. Compared with levels normally encountered in European cephalopods, Cd concentrations in both species were very high: 30.7–47.1 and 27.3–54.4 μg/g dry weight in Graneledone sp. and Benthoctopus thielei, respectively; Cu concentrations were generally low while Zn concentrations exhibited similar levels. Distribution of Cd in tissues showed that the high levels of Cd in Kerguelen octopuses resulted from very high levels of the metal in the digestive gland (369 and 215 μg/g dry wt in Graneledone sp. and Benthoctopus thielei, respectively). The digestive gland accumulated about 90% of the total Cd in the whole animal. Due to the very high concentrations of Cd in the Kerguelen octopuses, we hypothesize that these species play an important role in the process of Cd transfer throughout the food chain to top vertebrate predators in this area. Received: 2 June 1997 / Accepted: 30 October 1997     

Selenium and Mercury in Native and Introduced Fish Species of Patagonian Lakes,Argentina

A survey of mercury (Hg) and selenium (Se) contents was performed in fish collected from lakes located in two National Parks of the northern patagonian Andean range. Two native species, catfish (Diplomystes viedmensis) and creole perch (Percichthys trucha), and three introduced species, brown trout (Salmo trutta), rainbow trout (Oncorhynchus mykiss), and brook trout (Salvelinus fontinalis), were caught from lakes Nahuel Huapi, Moreno, Traful, Espejo Chico, and Guillelmo belonging to Nahuel Huapi National Park and from lakes Futalaufquen and Rivadavia, Los Alerces National Park. In lake Moreno, fish diet items were analyzed and rainbow trout grown in a farm. Hg and Se were measured in muscle and liver tissues by instrumental neutron activation analysis. The average concentrations in muscle of Hg for all species, ages, and lakes are between 0.4 to 1.0 μg g⁻¹ dry weight (DW) with a few fish, mainly native, exceeding the United States Environmental Protection Agency health advisory for freshwater fish limited consumption, and from 0.8 to 1.5 μg g⁻¹ DW for Se. Average concentrations in liver of Hg in all species range from 0.4 to 0.9 μg g⁻¹ DW. Brown trout, the top predator in these lakes, showed the lowest average Hg burden in both tissues. Se concentrations in the liver of brown and rainbow trout, up to 279 μg g⁻¹ DW, are higher than those expected for nearly pristine lakes, exceeding 20 μg g⁻¹ DW, the threshold concentration associated with Se toxicity. These species show lower Hg contents in muscle, suggesting a possible detoxification of Hg by a Se-rich diet. Creole perch and velvet catfish livers have lower Se concentrations, with a narrower span of values (2.3 to 8.5 μg g⁻¹ and 3.3 to 5.5 μg g⁻¹ DW respectively).     

Cadmium and Other Metal Levels in Autopsy Samples from a Cadmium-Polluted Area and Non-polluted Control Areas in Japan

This study was initiated to examine accumulation of cadmium (Cd) and other metals in kidney and liver in autopsy samples and to compare the levels between those in an area with heavy Cd exposure and those in no-polluted areas in Japan. Data on Cd and other metals in kidney (cortex and medulla) and liver in 95 cases (87 women and eight men; the exposed) in a Cd-polluted area and 43 cases (21 women and 22 men; the controls) in non-polluted areas were cited from 15 previous publications to be summarized together with six unpublished cases. Cd levels in kidney cortex and medulla were significantly lower in the exposed (31.5 and 23.8 μg/g wet tissue as GM, respectively) than in the controls (82.7 and 36.4 μg/g, respectively), whereas Cd levels in liver was higher in the exposed (60.2 μg/g) than in the controls (8.1 μg/g). Exposed women had lower Cd in the cortex (29.9 μg/g) and medulla (22.7 μg/g) than exposed men (55.4 and 38.1 μg/g, respectively) as well as in cortex of control women (92.9 μg/g). Comparison with worldwide data other than Japan for non-exposed populations [19.1, 9.3, and 1.3 μg/g in cortex, medulla, and liver, respectively, as the inverse variance-weighted averages (IVWA) of GM values for each of 22 reports] suggests that the levels for the non-exposed Japanese (123.3, 33.5, and 3.9 μg/g as IVWA) tended to be higher than the levels in other countries, possibly reflecting high dietary Cd intake in the past.     

Age,growth and reproductive biology ofNotothenia squamifrons gunther, 1880 from the Indian sector of the Southern Ocean

Summary The growth ofNotothenia squamifrons is analysed using scale reading of specimens from various isolated areas of the Indian sector of the Southern Ocean (Kerguelen, Crozet and Marion Islands; Ob, Lena and Kara-Dag seamounts). Studying reproductive biology reveals that spawning is annual and occurs during austral spring. Hatching takes place in summer. Scaling is set during the autumn. The smallest scaled fish measure 3.8 cm in total length. The data mentioned above, the check number on the scales and the sampling dates lead to the identification of the different age groups. Differences in growth rate appear between the studied areas. The fastest growth is observed around the Kerguelen Islands where the oldest specimens are 19 years old and reach 52 cm in total length. On the other hand, in the Crozet population,N. squamifrons does not live more than 12 years for a maximum length of 30 cm. Scale reading in fish from the Ob and Lena seamounts shows a minor decrease in growth during the winter season when compared to that in the other areas. The hydrographical conditions of this sector of the Southern Ocean may, in part, explain these differences: especially temperature and plankton biomass seem to effect growth rate. The cold antarctic waters and the highest plankton productivity, inducing the optimal growth rate, are found in the Kerguelen Islands.     

A northern rockhopper penguin unveils dispersion pathways in the Southern Ocean

We report the first record of a northern rockhopper penguin Eudyptes moseleyi on the Kerguelen Islands, Southern Indian Ocean. The penguin must have crossed the subtropical convergence to reach the island. This species was recently proved to be genetically different from the subantarctic eastern rockhopper penguin E. filholi that normally breeds on the Kerguelen Islands. The sequencing of a part of the mitochondrial control region shows that this bird may come from the population of Gough Island, 6,000 km away, in the south Atlantic Ocean. This finding confirms that the genetic isolation between these two penguin species is complete, although some individuals may sporadically disperse between the breeding sites. This first direct observation of a disperser from the Atlantic to the Indian Ocean also adds further support to a biogeographic dispersion pattern already suggested by phylogeographic patterns in other species from the Southern Ocean.     

Cadmium and zinc content of fish from an industrially contaminated lake

Eleven species of fish from an industrially-contaminated lake were analysed for whole body cadmium and zinc content by atomic absorption spectrophotometry. Cadmium and zinc content of fish were species related, and most species accumulated these trace metals to levels significantly higher than background. Maximum concentrations detected were 13.60 μg Cd g⁻¹ (dry wt) in a bluegill and 820 μg Zn g⁻¹ in a redear sunfish. Cadmium content was much more variable than zinc content. Distributions of concentrations of both cadmium and zinc in fish were lognormal, and concentrations of both metals tended to decrease in higher trophic levels. Zinc concentrations significantly decreased as total length increased in three species.     

Fate and effects of cadmium in an experimental marine ecosystem

Two recirculated marine seawater systems (capacities: 150 and 300 l) were used for the study on cadmium accumulation of biological filter sludge, by the musselMytilus edulis and the plaicePleuronectes platessa for a period of up to 300 days. In the contaminated system Cd concentrations varied from 2.5 to 7.0 g/l with a mean of 4.6±1.15 g/l (control: 1.04±0.46 g/l). Accumulation of Cd by the filter sludge from the control system as well as from the contaminated system was significant. Mean concentrations of control-and contaminated sludge over the experimental period were 2.01±0.86 ng Cd/mg dry wt and 9.98±3.55 ng Cd/mg dry wt respectively. Accumulation of Cd byM. edulis both in the control and in the contaminated system was considerable. After 163 days of exposure the whole body burden of mussels rose from 0.3 ng Cd/mg dry wt to around 10 ng Cd/mg dry wt in the controls and to 70 ng Cd/mg dry wt in the contaminated systems. Accumulation of Cd byP. platessa was analysed in backbone, fins, gills, liver, muscle (fillet), otolith and skin (dorsal and ventral) over a period of 280 days. Elevated Cd contents of livers from control specimens were noticed after 200 days and reached 1.75 ng Cd/mg dry wt in liver. There was considerable accumulation in the liver (maximum values: 3.0 ng Cd/mg dry wt) and gills (6.0 ng Cd/mg dry wt) of specimens from the contaminated system, Cd contents of plaice exposed for identical periods of time were very variable. Growth of plaice living in the contaminated system was at times significantly slower than that of the control group. Of the three biological objects tested-filter sludge,M. edulis, P. platessa—the mussel seemed to be the most sensitive indicator of elevated Cd-concentrations, while the reaction of the plaice was slow and less distinct.     

Subantarctic flowering plants: pre‐glacial survivors or post‐glacial immigrants?

Aim The aim here was to assess whether the present‐day assemblage of subantarctic flowering plants is the result of a rapid post‐Last Glacial Maximum (LGM) colonization or whether subantarctic flowering plants survived on the islands in glacial refugia throughout the LGM. Location The circumpolar subantarctic region, comprising six remote islands and island groups between latitudes 46° and 55° S, including South Georgia in the South Atlantic Ocean, the Prince Edward Islands, Îles Crozet, Îles Kerguelen, the Heard Island group in the South Indian Ocean and Macquarie Island in the South Pacific Ocean. Methods Floristic affinities between the subantarctic islands were assessed by cluster analysis applied to an up‐to‐date dataset of the phanerogamic flora in order to test for the existence of provincialism within the subantarctic. A review of the primary literature on the palaeobotany, geology and glacial history of the subantarctic islands was carried out and supplemented with additional palaeobotanical data and new field observations from South Georgia, Île de la Possession (Îles Crozet) and Îles Kerguelen. Results First, a strong regionalism was observed, with different floras characterizing the islands in each of the ocean basins, and endemic species being present in the South Indian Ocean and South Pacific Ocean provinces. Second, the majority of the plant species were present at the onset of accumulation of post‐glacial organic sediment and there is no evidence for the natural arrival of new immigrants during the subsequent period. Third, a review of geomorphological data suggested that the ice cover was incomplete during the LGM on the majority of the islands, and ice‐free biological refugia were probably present even on the most glaciated islands. Main conclusions Several independent lines of evidence favour the survival of a native subantarctic phanerogamic flora in local refugia during the LGM rather than a post‐LGM colonization from more distant temperate landmasses in the Southern Hemisphere.     

Cadmium,cobalt, chromium,and experimental myocardial infarction

In the case of experimental heart muscle infarction, the infarcted tissue of 18 pigs had a cadmium content of 0.38 μg/g dry weight and a cobalt content of 0.45 μg/g dry weight. In 25 non-infarcted pig hearts, the cadmium concentration amounted to 0.27 μg/g dry weight and the cobalt concentration to 0.37 μg/g dry weight. Thus, as far as the infarcted heart muscle tissue is concerned, there is a highly significant increase in the cadmium content (p<0.01) and a significant increase in cobalt content (p<0.05) compared to a non-infarcted heart. No differences were established with regard to chromium concentrations.     

Age-dependent changes in metallothionein levels in liver and kidney of the Japanese

Samples of liver, renal cortex, and medulla were obtained from 55 forensic autopsies (0- to 95-yr-old Japanese). Metallothionein (MT) was determined by the Ag-hem or Cd-hem method. Zinc (Zn), copper (Cu), and cadmium (Cd) were determined by atomic absorption spectrophotometry. The mean levels of MT were 250 μg/g in the liver, and 394 μg/g (cortex) and 191 μg/g (medulla) in the kidney. Age-dependent changes were observed in both the liver and kidney. In the liver, MT level decreased during infancy and increased thereafter with age. Similar age-dependent changes in the levels of Zn and Cu were observed. In the kidney cortex, MT level increased with age, although no correlation was found after middle age. The levels of Cd and Zn also increased with age until middle age; however, they decreased thereafter. These results suggest that age-dependent changes in renal MT levels are associated with accumulation of Cd.     

Heavy Metal Accumulation in Four Species of Sea Turtles from the Baja California Peninsula, Mexico

Heavy metals were assessed in four species of sea turtles from the Baja California Peninsula, Mexico, representing the first report of heavy metal concentrations in tissues of post-yearling sea turtles from the Eastern Pacific. Concentrations of Cd measured in C. mydas kidney (653 μg/g dry wt) were the highest ever reported for any sea turtle species. Cd accumulated preferentially in kidney and the ratios of kidney to liver Cd in Baja California turtles were among the highest reported for sea turtles globally. Zn, Ni, and Mn concentrations were also significantly higher in kidney than other tissues, while Cu and Fe were greatest in liver, and all metals were lowest in muscle. With the exception of one value (69.9 μg/g in kidney of C. caretta), Pb was low in all tissues from Baja California. In comparisons across species, kidney of C. mydas had greater Zn and Ni concentrations as compared to other species, although there was no difference in liver metal levels among the species. Positive correlations were detected in the concentrations of Cd, Cu and Ni with the straight carapace length of C. caretta.     

Effect of nutritional factors and cortisol on tyrosine aminotransferase activity in liver of brook trout, Salvelinus fontinalis Mitchill.

1. Starvation for over 50 days increased the activity of Tyrosine aminotransferase (TAT) from brook trout liver and decreased liver glycogen. 2. Cortisol (6-40 mg/100 g body wt) increased TAT activity, optimally 72 hr post-injection; liver glycogen response to cortisol was variable while tissue water either increased or remained constant. 3. Fish fed high-protein/low-carbohydrate had greater TAT activity than fish fed low-protein/high carbohydrate. There was food-induced peak of activity indicating a "diurnal rhythm" analogous to that of rat TAT. 4. TAT activity in brook trout appears to be correlated with protein catabolism.     

Metallothionein as Potential Biomarker of Cadmium Exposure in Persian Sturgeon (<Emphasis Type="Italic">Acipenser persicus</Emphasis>)

Metallothionein (MT) concentration in gills, liver, and kidney tissues of Persian sturgeon (Acipenser persicus) were determined following exposure to sublethal levels of waterborne cadmium (Cd) (50, 400, and 1,000 μg l⁻¹) after 1, 2, 4, and 14 days. The increases of MT from background levels were 4.6-, 3-, and 2.8-fold for kidney, liver, and gills, respectively. The results showed that MT level change in the kidney is time and concentration dependent. Also, cortisol measurement revealed elevation at the day 1 of exposure and followed by MT increase in the liver. Cd concentrations in the cytosol of experimental tissues were measured, and the results indicated that Cd levels in the cytosol of liver, kidney, and gills increased 240.71-, 32.05-, and 40.16-fold, respectively, 14 days after exposure to 1,000 μg l⁻¹ Cd. The accumulation of Cd in cytosol of tissues is in the order of liver > gills > kidney. Pearson correlation coefficients showed that the MT content in kidney is correlated with Cd concentration, the value of which is more than in liver and gills. Thus, kidney can be considered as a tissue indicator in A. persicus for waterborne Cd contamination.     

Population trends of female Elephant Seals breeding on the Courbet Peninsula, ?les Kerguelen

Southern Elephant Seals are upper marine predators of the Southern Ocean. As such, their population dynamics and fluctuations reflect environment conditions. Their worldwide populations crashed during the second half of the twentieth century for reasons not yet completely elucidated. Here, we studied the largest population of Southern Elephant Seals within the South Indian Ocean that are breeding on ?les Kerguelen. In a previous analysis, Guinet et al. in Antarct Sci 11:193–197, 1999) suggested that the decline on ?les Kerguelen might be over, as observed elsewhere. Using 10 years of additional data, we updated this analysis using state-of-the-art statistical methods to account for most uncertainties associated with count data. We showed that the population of female Southern Elephant Seals breeding on ?les Kerguelen has been stable over the past 20 years. Despite concomitant global changes within the Southern Ocean, we did not find any evidence of a phenological shift in peak haul-out date of breeding females between the 1970s and the 2000s.     

The use of the three-ridge clam (Amblema perplicata) to monitor trace metal contamination

The three-ridge clamAmblema perplicata was used to monitor two streams for the presence of zinc (Zn) and cadmium (Cd) derived from an industrial source. Clams were collected from a relatively uncontaminated area in one river and transported to four study sites in the two contaminated streams. The clams were placed into polyethylene cages and left in these streams for one week. Control clams were treated in a similar manner and left in the uncontaminated river.The highest mean concentration of Zn (956 µg/g dry wt) was found in the gill tissue of clams from the most contaminated site. The highest mean Cd concentration (18.6 µg/ g dry wt) was found in digestive glands of clams, also from the most contaminated site. Mean concentrations at contaminated sites were significantly higher than background and control levels; the findings suggest that these particular organs of clams may be useful in monitoring levels of Zn and Cd in other freshwater systems.     

Effects of warm sea-surface temperature anomalies on the blue petrel at the Kerguelen Islands

Several long-term studies on Southern Ocean seabirds and seals have suggested a possible link between major declines in breeding performance and El Niño Southern Oscillation events. We report that the breeding performances and body condition of the blue petrel (Halobaena carulea) on the Kerguelen Islands is depressed by episodic, warm sea-surface temperatures (SSTs) in the winter before breeding. Lagged cross correlations between SSTs in the Kerguelen sector and the Southern Oscillation Index indicate that warm SSTs were found south of Kerguelen Islands within a year of, and between 4.2 and 5.4 years after, an El Niño event took place. These results can be discussed with respect to the recently described Antarctic Circumpolar Wave that drives climatic anomalies eastward around the Southern Ocean.     

Estimation of Dietary Pb and Cd Intake from Pb and Cd in Blood or Urine

Successful trials were made to estimate the dietary daily intake of lead (Pb) and cadmium (Cd) via foods from the levels of the metals in blood or urine. In practice, 14 and 15 reports were available for Pb and Cd in blood (Pb-B and Cd-B), urine (Pb-U and Cd-U) and 24-h diet duplicates (Pb-D and Cd-D), respectively, from which 68 pairs each of Pb or Cd in blood and food duplicates [each being geometric mean (GM) values for the survey sites] were obtained. Regression analysis revealed that there was a significant correlation between Pb-B and Pb-D, and also between Cd-B and Cd-D, suggesting that it should be possible to estimate both Pb-D and Cd-D from Pb-B and Cd-B, respectively. For Cd-U, the number of available cases was limited (20 pairs), but a significant correlation was detected between Cd-U (as Cd-U_cr, or Cd levels in urine as corrected for creatinine concentration) and Cd-D. Care should be taken in estimating Pb-D from Pb-B, as the ratio of Pb-D over Pb-B may decrease as a function of increasing Pb-B levels. The Pb-D (μg/day) for typical Japanese women with Pb-B of 15 μg/l was best estimated to be 13.5 μg/day. No Cd-B- or Cd-U_cr-dependent change was detected in case of Cd. The best estimate of Cd-D for Cd-B at 1.5 μg/l should be about 19.4 μg/day.     

Cadmium exposure of rainbow trout, Salmo gairdneri Richardson: effects on immune functions

Differential leucocyte counts, phagocytosis, humoral antibody response and the in vitro blasto-genetic response to mitogens (lipopolysaccharide and Concanavalin A) and to an antigen ( Vibrio anguillarum ) were studied in rainbow trout exposed to 0,0.7 or 3.6 μg Cd 1⁻¹ for 12 weeks.
Although the fish did not exhibit any clinical or histological changes, cadmium exposure was found to affect two of the immune parameters measured. The cellular response of fish immunized with V. anguillarum to the homologous antigen was significantly lower for splenocytes obtained from fish exposed to cadmium for 9 weeks (3.6 μg Cd 1⁻¹ group) than for splenocytes obtained from non-exposed fish. Conversely, the humoral antibody response to V. anguillarum O-antigen was higher in the 3.6 μg Cd 1⁻¹ group than in the non-exposed group. Protective immunity of fish vaccinated against V. anguillarum was equally as good in the cadmium-exposed group as in the non-exposed group. No cadmium-induced changes in differential leucocyte counts or in the proportions of phagocytic cells were observed.     

Trace elements in tissues of white-chinned petrels (Procellaria aequinoctialis) from Kerguelen waters,Southern Indian Ocean

The use of seabirds to assess marine contamination by trace elements in areas remote from pollutant emission points has already been done at various latitudes. Nevertheless, little information is available concerning the Southern Indian Ocean. Determining the contaminants levels, there appears necessary not only due to several deleterious effects reported in literature, but also as previous studies have highlighted elevated concentrations of cadmium (Cd) and mercury (Hg) in mollusks, crustaceans and fish. Within this context, the white-chinned petrel appears as a key species due to its lifespan, diet and trophic position. Thirty-three accidentally killed (collision with lights/bycatch in longline vessels) individuals collected in Kerguelen waters were analysed for Cd, copper (Cu), Hg, selenium (Se) and zinc (Zn) in liver, kidney, pectoral muscle, feathers and for mature males, testis. Elevated Hg concentrations (average 58.4 μg g^?1 dw in liver) are likely due to the presence of mesopelagic prey in the diet of Procellaria aequinoctialis. Cd concentrations (average of 65.7 μg g^?1 dw in kidney) can be attributed to a high level of fisheries offal consumption, as well as crustacean and squid ingestion. Correlation of Hg with Se indicates its detoxification by co-precipitation, and correlation of Cd with Zn suggests its displacement by Cd on metallothioneins binding sites. This work also indirectly confirms ecological data (range and diet composition) from the wintering period of the species, which is rather scarce. Seasonal diet change and moulting accounted more for the obtained results than sex of the birds.     

Influence of the diet on the bioaccumulation of heavy metals in zooplankton-eating petrels at Kerguelen archipelago,Southern Indian Ocean

Concentrations of cadmium, mercury, copper and zinc were measured in muscle, kidney and liver tissues and in the main prey of five species of zooplankton-eating petrels: blue petrel (Halobaena caerulea), thin-billed (Pachyptila belcheri) and Antarctic (P. desolata) prions, and South Georgian (Pelecanoides georgicus) and common (Pelecanoides urinatrix) diving petrels. Since some of these species are closely related species with respect to body size, timing of moult and life span, their diet has been examined to evaluate its influence on heavy-metal bioaccumulation. Inter-specific differences were significant for Hg concentrations in the liver and for Zn concentrations in both liver and kidney tissues. Blue petrels exhibited the highest Hg concentrations in the liver (3.9±2.02 µg.g^–1 wet weight). No significant differences were found in Cd concentrations between species. Exposure to heavy metals through the most important prey species in the diet during the breeding period was evaluated. The most evident result was the influence of fish prey on Hg levels. Although crustacean species exhibit different cadmium concentrations, the diet composition does not appear to be discriminant for Cd bioaccumulation within the small petrel community at Kerguelen.