Heavy metals in the clam Megapitaria squalida collected from wild and phosphorite mine-impacted sites in Baja California, Mexico

The “chocolate clam” Megapitaria squalida, is widely consumed by the population of several localities along the Pacific coast. Clams collected from seven stations in Bahía de la Paz, a bay within the Gulf of California, before and after the summer rainy season were analyzed for Pb, Ni, Cd, Mn, Zn, Cu, and Fe. The location of the sampling sites significantly affected the concentration of metals in clam tissues, but not in relation to the proximity to alleged contaminated sites. Clams from a site close to a phosphate mine had the highest levels of Pb, but only in April, and the highest concentrations of Cd were recorded in clams collected in areas with no anthropogenic activities. Clams from sites considered clean had higher levels of Cd, Fe, Zn, and Mn. The mean concentrations (μg/g dry weight) ranged from 0.1 to 7.8 for Pb, from 1.9 to 8.8 for Ni, from 1.5 to 11.1 for Cd, from 2.5 to 14.1 for Mn, from 47.2 to 64.6 for Zn, from 5.4 to 18.7 for Cu, and from 154 to 558 for Fe. Collecting clams in sites apparently pristine is no guarantee that metals will be in low concentrations.     

The impact of an industrially contaminated lake on heavy metal levels in its effluent stream

Levels of cadmium and zinc in various components of Williamson Ditch (an industrially contaminated stream flowing into Palestine Lake), Trimble Creek (a stream draining Palestine Lake) and the Tippecance River (a river receiving Trimble Creek) were determined. Water, sediment, plant, fish and clam samples were analyzed for cadmium and zinc content by atomic absorption spectrophotometry. Unweighted mean metal concentrations in Trimble Creek were the following: water, 51 µg Zn/1 and 4.2 µg Cd/1; sediment, 592 µg Zn/g and 48.8,µg Cd/g; plants, 375 µm Zn/g and 7.91 µg Cd/g; fish, 145 µg Zn/g and 6.02 µg Cd/g. These concentrations were generally lower than those found in Williamson Ditch and higher than those found in the Tippecanoe River or background levels previously reported for other aquatic ecosystems.     

Zinc tolerance and accumulation in metallicolous and nonmetallicolous populations of Arabidopsis halleri (Brassicaceae)

Zinc tolerance was investigated in five populations of Arabidopsis halleri (syn.: Cardaminopsis halleri ) raised from seeds collected from contaminated and uncontaminated sites. Tolerance was measured by determining the concentration which inhibited root growth (EC₁₀₀). A. halleri populations from contaminated and uncontaminated sites were found to be Zn-tolerant compared with the Zn-nontolerant species Arabidopsis thaliana and A. lyrata subsp. petraea . At very high Zn concentrations, populations of A. halleri from uncontaminated sites were slightly less Zn-tolerant than those from contaminated sites. These observations support the hypothesis that in A. halleri , Zn tolerance is largely a constitutive property. One population from an uncontaminated site and one population from a contaminated site were studied for Zn uptake. Zinc content was measured in shoots and roots using a colorimetric test under laboratory conditions. The results showed that whatever their origin, individuals from both populations are Zn accumulators compared with the nonaccumulator species A. thaliana . Moreover, the population from the uncontaminated area accumulated Zn in its shoots and roots more quickly than the population from the contaminated site. These results suggest that, in A. halleri , Zn accumulation to very high concentration is a constitutive property.     

Uptake and distribution of cadmium in maize inbred lines

Genotypic variation in uptake and distribution of cadmium (Cd) was studied in 19 inbred lines of maize (Zea mays L.). The inbred lines were grown for 27 days on an in situ Cd-contaminated sandy soil or for 20 days on nutrient solution culture with 10 µg Cd L^-1. The Cd concentrations in the shoots showed large genotypic variation, ranging from 0.9 to 9.9 µg g^-1 dry wt. for the Cd-contaminated soil and from 2.5 to 56.9 µg g^-1 dry wt. for the nutrient solution culture. The inbred lines showed a similar ranking for the Cd concentrations in the shoots for both growth media (r²=0.89). Two main groups of inbreds were distinguished: a group with low shoot, but high root Cd concentrations (shoot: 7.4±5.3 µg g^-1 dry wt.; root: 206.0±71.2 µg g^-1 dry wt.; shoot Cd excluder) and a group with similar shoot and root Cd concentrations (shoot: 54.2±3.4 µg g^-1 dry wt.; root: 75.6±11.2 µg g^-1 dry wt.; non-shoot Cd excluder). The classification of the maize inbred lines and the near equal whole-plant Cd uptake between the two groups demonstrates that internal distribution rather than uptake is causing the genotypic differences in shoot Cd concentration of maize inbred lines. Zinc (Zn), a micronutrient chemically related to Cd, showed an almost similar distribution pattern for all maize inbred lines. The discrepancy in the internal distribution between Cd and Zn emphasizes the specificity of the Cd distribution in maize inbred lines.     

The effects of heavy metals on microbial biomass in sediments of Palestine Lake

Effects of metal contamination on microbial biomass in sediment samples from three areas in Palestine Lake (one area highly polluted with chromium, cadmium and zinc) were determined. Adenosine triphosphate (ATP) concentrations, determined by the luciferin-luciferase bioluminescent technique, and microbial colony numbers on pour plates were used as biomass indicators. Plate counts showed a significant (P < 0.01) site effect with the highly contaminated area having an order of magnitude lower microbial population than the control area. ATP concentrations also indicated lower microbial biomass in contaminated sediments. The metal concentrations of the most contaminated area averaged 17,840 µg Zn/g, 4380 µg Cr/g and 585 µg Cd/g based on dry weight of sediments. A suppression of organic decomposition was evident in the impacted area; high metal levels and resultant low microbial biomass may have been causative.     

Combined Effect of Dietary Cadmium and Benzo(a)pyrene on Metallothionein Induction and Apoptosis in the Liver and Kidneys of Bank Voles

Bank voles free living in a contaminated environment have been shown to be more sensitive to cadmium (Cd) toxicity than the rodents exposed to Cd under laboratory conditions. The objective of this study was to find out whether benzo(a)pyrene (BaP), a common environmental co-contaminant, increases Cd toxicity through inhibition of metallothionein (MT) synthesis-a low molecular weight protein that is considered to be primary intracellular component of the protective mechanism. For 6 weeks, the female bank voles were provided with diet containing Cd [less than 0.1 μg/g (control) and 60 μg/g dry wt.] and BaP (0, 5, and 10 μg/g dry wt.) alone or in combination. At the end of exposure period, apoptosis and analyses of MT, Cd, and zinc (Zn) in the liver and kidneys were carried out. Dietary BaP 5 μg/g did not affect but BaP 10 μg/g potentiated rather than inhibited induction of hepatic and renal MT by Cd, and diminished Cd-induced apoptosis in both organs. The hepatic and renal Zn followed a pattern similar to that of MT, attaining the highest level in the Cd + BaP 10-μg/g group. These data indicate that dietary BaP attenuates rather than exacerbates Cd toxicity in bank voles, probably by potentiating MT synthesis and increasing Zn concentration in the liver and kidneys.     

The distribution of Pb,Zn, Cd and Cu within the pulmonate mollusc Helix aspersa müller

Summary The distribution of Pb, Zn, Cd and Cu throughout the body tissues of Helix aspersa was determined. The digestive gland of the mollusc was shown to be an important store of Pb, Zn and Cd while Cu was found to be more evenly distributed throughout the tissues of the animal. These results are discussed with relation to previous work concerning heavy metal content in molluscs. The selectivity of the digestive gland for Cd was higher than it was for either Pb or Zn and it is suggested that analysis of the digestive gland of molluscs may be useful in studying levels of Cd at different sites.At a contaminated site the levels of Cd in Helix aspersa were shown to be 13 times greater than at a relatively uncontaminated site.     

Metals contents in two fishes of different feeding behaviour in the Lower Paraná River and Río de la Plata Estuary

Cd, Cr, Cu and Pb concentrations were measured in the water and these plus Zn were measured in the diet, muscle and liver of the detritivorous fish Prochilodus lineatus and the omnivorous fish Pterodoras granulosus at two sites (Lower Paraná River and Río de la Plata right margin) located upstream and downstream, respectively, from Buenos Aires, an important source of xenobiotics. Cu and Cr concentrations in water were higher in the Río de la Plata coastal waters, while Cd and Pb were below detection limits. The stomach contents of P. lineatus showed a higher metal content at the estuary, attaining concentrations within the range reported for contaminated sediments. However, metals in fish tissue were not higher at the estuary and, except for Cd in liver, were lower than in the organic fraction of the stomach content. Thus, only Cd was accumulated. The P. granulosus diet was composed mainly of river vegetation debris and clams, Corbicula fluminea, at the estuary. Cd, Cu and Pb in liver were higher at the estuary while only Cu was higher in the diet at this site. The different nature of the diet seems associated with a differential bioavailability of its metal content. P. granulosus accumulates Cu at both sites and Cd at the estuary. Both fishes showed higher metal content in liver than in muscle. Cr in liver was below detection limits. No relation was found between metal content and fish size. Overall, metal content in fish tissues were low, except for Cu in P. granulosus and Cd in P. lineatus, similar to those of uncontaminated sites, suggesting that homeostatic mechanisms prevent metal accumulation.     

Metal exposures to native populations of the caddisfly Hydropsyche (Trichoptera: Hydropsychidae) determined from cytosolic and whole body metal concentrations

Metal concentrations of the soluble fraction of the cytoplasm (cytosol) and the whole body were determined in the caddisfly Hydropsyche spp. (Trichoptera). Metal accumulation in the cytosol and the whole body were compared in samples collected along 380 kms of a contamination gradient in the Clark Fork river in four consecutive years (1992–1995), and from a contaminated tributary (Flint Creek). Samples from the contaminated sites were compared to an uncontaminated tributary (Blackfoot River). Relations between cytosolic metal concentration and cytosolic protein (used as a general biomarker of protein metabolism) also were examined in 1994 and 1995. Relative to whole body concentrations, cytosolic metal concentrations varied among metals and years. Spatial patterns in whole body and cytosolic Cd, Cu and Pb concentrations were qualitatively similar each year, and these concentrations generally corresponded to contamination levels measured in bed sediments. The proportions of metals recovered in the cytosol of ranged from 12 to 64% for Cd and Cu and from 2 to 38% for Pb. Zinc in the whole body also was consistent with contamination levels, but cytosolic Zn concentrations increased only at the highest whole body Zn concentrations. As a result, the proportion of Zn recovered in the cytosol ranged from 16 to 63% and tended to be inversely related to whole body Zn concentrations. The proportions of cytosolic metals varied significantly among years and, as a result, interannual differences in metal concentrations were greater in the cytosol than in the whole body. The results demonstrated that Hydropsyche in the river were chronically exposed to biologically available metals. Some features of this exposure were not evident from whole body concentrations. In general, protein levels did not correspond to cytosolic metal concentrations. A variety of environmental factors could interact with metal exposures to produce complex responses in protein metabolism. Systematic study will be necessary to differentiate the effects of multiple environmental stressors on organisms living in contaminated ecosystems. This revised version was published online in July 2006 with corrections to the Cover Date.     

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.     

APPLIED ISSUES Species- and population-specific responses of translocated hydropsychid larvae (Trichoptera, Hydropsychidae) to runoff from acid sulphate soils in tin River Kyrönjoki, western Finland

1. The effects of runoff from acid sulphate soils on Hydropsyche angustipennis, H. siltatai and Ceratopsyche nevae larvae were studied. H. angustipennis occurs in both contaminated and uncontaminated rivers, whereas H. siltalai and C. nevae occur only in uncontaminated rivers. Larvae were translocated in PVC-tubes to contaminated sites. Larvae returned to an uncontaminated river were used as a control. 2. Heavy larval mortality and a high incidence of morphological abnormalities were observed in larvae translocated to the contaminated, acid dyers. In the control river pH remained near 6 and no larval mortality or morphological abnormalities were observed. In the most contaminated river nutrient concentrations, amount of organic matter and pH increased substantially after the flood. 3. Mortality and incidence of abnormalities were significantly higher in H. siltalai and C. nevae than in H. angustipennis. As metal concentrations decreased and pH increased, the larvae of all species developed normally, except in the most contaminated river, where only H. angustipennis appeared to tolerate the increasing load of nutrients and organic matter. 4. Reciprocal translocation of H. angustipennis larvae between contaminated and uncontaminated rivers revealed significant differences in larval development and the occurrence of abnormalities among sites and populations. At both sites, larvae originating from the contaminated site grew more slowly than did larvae from the uncontaminated site. Morphological abnormalities were detected only in H. angustipennis larvae translocated from the uncontaminated to the contaminated site. 5. The results suggest that species-specific differences in sensitivity to acidification, metal contamination and eutrophication are the major determinants of hydropsychid guild structure in the River Kyrönjoki. Further, population-specific differences in growth and occurrence of morphological abnormalities in the H. angustipennis larvae may reveal either phenotypic adaptation or evolution of resistance to runoff from acid sulphate soils.     

The effects of heavy metal pollution on genetic diversity in zinc/cadmium hyperaccumulator Sedum alfredii populations

The genetic diversity and population structure of seven populations of Sedum alfredii growing in lead/zinc (Pb/Zn) mine spoils or in uncontaminated soils from eastern and southern China were investigated using random amplified polymorphic DNA (RAPD) technology. Four of the sampled sites were heavily contaminated with heavy metals (Zn, Cd, Pb), and extremely high concentrations of Zn, Cd, and Pb were found among these corresponding populations. A significant reduction of genetic diversity was detected in the mining populations. The reduction of genetic diversity could be derived from a bottleneck effect and might also be attributed to the prevalence of vegetative reproduction of the mining populations. Analysis of molecular variance (AMOVA) and the unweighted pair group method with arithmetic mean (UPGMA) tree derived from genetic distances further corroborated that the genetic differentiation between mine populations and uncontaminated populations was significant. Polymorphism with the heavy metal accumulation capability of S. alfredii probably due to the genetic variation among populations and heavy metal contamination could have more impact on the genetic diversity and population structure of S. alfredii populations than geographic distance.     

Metabolism-independent binding of toxic metals by Ulva lactuca: cadmium binds to oxygen-containing groups, as determined by NMR

The metabolism-independent metal binding characteristics of Ulva lactuca were investigated using both freeze-dried thalli and cell walls stripped of intracellular material by incubation in Triton-X followed by methanol. Biosorption of Cd, Zn, Cu and Co by freeze-dried thallus was concentration-dependent and followed Freundlich and Langmuir isotherms. The Freundlich plot suggested that freeze-dried U. lactuca had the greatest binding affinity for Cu compared with Cd, Zn and Co. The BET (Brunauer–Emmett–Teller) plot, which indicates a more complex form of adsorption, and the Scatchard plot were not adequate models for Cu adsorption. The Scatchard plot of Cd suggested that two Cd binding sites were available on the freeze-dried thallus, with the second, lower affinity site only becoming available at Cd loading capacities greater than 4.9mmol g dry wt. Cd nuclear magnetic resonance (NMR) studies confirmed that two binding sites were available for Cd on the freeze-dried algal powder, though only one was available on the cell wall, and that the affinity of the binding sites was greater for Cu than for Cd. The results of the NMR experiments suggested that Cd binds to oxygen-containing functional groups in the algal powder and on the cell wall. It is proposed that sulphate or hydroxyl groups attached to polysaccharide subunits are possible sites.     

Effects of Amendments on Growth and Uptake of Cd and Zn by Wetland Plants,Typha angustifolia and Colocasia esculenta from Contaminated Sediments

A pot study was conducted to compare the effects of amendments (CaHPO₄ and cow manure) on growth and uptake of Cd and Zn from contaminated sediments by two wetland plant species, Typha angustifolia and Colocasia esculenta. Contaminated sediments (Cd 33.2 mg kg^–1 and Zn 363 mg kg^–1) were collected from Mae Tao basin, Mae Sot district, Tak province, Thailand. The experiment consisted of 4 treatments: control (uncontaminated sediment), Cd/Zn, Cd/Zn + 5% CaHPO₄, and Cd/Zn + 10% cow manure. Plants were grown for 3 months in the greenhouse. The addition of CaHPO₄ resulted in the highest relative growth rate (RGR) and highest Cd accumulation in both T. angustifolia and C. esculenta while the lowest RGR was found in C. esculenta grown in the cow manure treatment. Both plant species had higher concentrations of metals (Cd, Zn) in their belowground parts. None of the amendments affected Zn accumulation. C. esculenta exhibited the highest uptake of both Cd and Zn. The results clearly demonstrated the phytoremediation potential of C. esculenta and the enhancement of this potential by CaHPO₄ amendment.     

Effects of mine effluent on uptake of Co,Ni, Cu,As, Zn,Cd, Cr and Pb by aquatic macrophytes

Concentrations of Ni, Co, Cu, Pb, Zn, Cd, Cr and As were determined in aquatic sediments, water and macrophytes collected from a fluvial system, contaminated by mine effluents. Myriophyllum verticillatum collected in May below the trace element point source accumulated 169 µg/g of Ni, 860 µg/g of Co, 37 µg/g of Cu, 31 µg/g of Pb, 92 µg/g of Zn, 6.9 µg/g of Cr and 1,200 µg/g of As (concentrations in dry weight). The aquatic macrophytes Nymphaea odoratae and Pontederia cordata accumulated the investigated trace elements to a much lesser extent. The concentrations of trace elements in Myriophyllum verticillatum decreased from May to August. Correlations were found between the concentrations of total Ni, Co and Cu in the bottom sediment and in the submerged macrophytes. However, there was no correlation between the amounts of these trace elements extractable by 0.5 N HCl from the sediments and the concentrations in the macrophytes.     

Biochemical changes in longear sunfish, Lepomis megalotis, associated with lead, cadmium and zinc from mine tailings

Longear sunfish were collected from a stream contaminated with mine tailings rich in lead (Pb), cadmium (Cd) and zinc (Zn). Blood samples were analysed for δ-aminolevulinic acid dehydratase (ALA-D) activity and Pb concentration. Vertebrae were tested for bone strength and composition, and Pb, Zn, and Cd concentrations were determined in muscle tissue. ALA-D activity was negatively correlated with blood Pb concentration ( r =–0.66), and enzyme activity was significantly higher and blood Pb significantly lower at the reference site than at the contaminated sites. Blood Pb was highly correlated with Pb in muscle tissue ( r = 0.72), and the concentrations of Pb and Cd in muscle tissues were themselves correlated ( r = 0.64). In fish from contaminated sites, two of the mechanical properties of the vertebrae measured (elastic limit and modulus of elasticity) were significantly different from values in fish from the reference site. These properties and one other (stress) were weakly correlated with muscle Cd concentration (0.42 < r < 0.46). Biochemical differences among fish from different sites were also evident; concentrations of calcium, phosphorus and collagen were lower in the vertebrae of fish from some of the contaminated sites than at the reference site, and bone phosphorus was negatively correlated with concentrations of Pb in both muscle ( r =– 0.62) and blood ( r =– 0.75). Collectively, these results indicate that, in addition to the well-documented effects of Pb on haem synthesis, other important biochemical pathways may be disrupted by continuous low-level exposure to elemental contaminants.     

Some aspects of hepatic function in feral brown trout, Salmo trutta, living in metal contaminated water

Brown trout, Salmo trutta, exposed to heavy metals (mainly Cd and Zn) for at least 2 years in the Eagle River, Colorado, were examined for liver size and activity of the growth-promoting enzyme, ornithine decarboxylase (ODC) and compared to trout living in an uncontaminated site. Liver-somatic index (LSI) was greater for trout living in the uncontaminated site with the LSI of females being significantly greater than that of males. The LSI for females at the uncontaminated site was greater than that of females at the contaminated site, but males were not different statistically. ODC activity in the livers of both males and females was lower at the contaminated site. However, males and females did not differ with respect to ODC activity. These data suggest that chronic exposure to heavy metals may have important implications for growth and reproduction and possibly survival. The activity of ODC in liver might serve as a useful biomarker when assessing chronic toxicity of metals to naturally reproducing fish populations.     

Distribution and Risk Assessment of Heavy Metals in the Xinzhuangzi Reclamation Soil from the Huainan Coal Mining Area,China

The contamination of coal-mine soil by heavy metals is a widespread problem. This study analyzes the heavy metals (Cu, Zn, Ni, Pb, Cr, Cd, and Hg) found in 33 surface soil samples from Xinzhuangzi, China restored coal-mining land used as cultivated land. The results show that the selected elements were cumulative, especially for Cd. An index of geo-accumulation indicates that the soil was practically uncontaminated by Cu, Zn, Ni, and Hg, uncontaminated to moderately contaminated by Pb and Cr, and moderately to heavily contaminated by Cd. Based on the U.S. Environmental Protection Agency's ecological soil screening levels (Eco-SSLs) for Cu, Zn, Ni, Pb, and Cd and the Dutch Target and Intervention Values for Cr and Hg, the plants and soil invertebrates were not likely greatly influenced by the selected metals. Although the Cd concentration was found to have no significant effect on plants and soil invertebrates, it is the only metal with a concentration significantly above that required by Chinese standards (HJ/T 332–2006) for edible agricultural products, indicating that Cd is the predominant factor that determines the use of the reclaimed coal-mining area for farmland. Thus, employing the reclaimed land as farmland may not be a good option.     

Does cadmium pollution affect reproduction in the clam Ruditapes decussatus? A one-year case study

The effect of cadmium (Cd) on the reproduction of Ruditapes decussatus was monitored over a period of 12 months, from June 2001 to June 2002. Two sites "Bordj d'Ungha" and "El Hofra" differing by their degree of cadmium contamination were chosen in the Gulf of Gabès area (Tunisia). Annual mean concentrations of Cd in the whole soft tissues of clams from the site El Hofra were more than 4 times higher than those from the site Bordj d'Ungha (reference site). The gametogenic cycle of the clam R. decussatus was also investigated by histological examination and monthly observations of gonadal sections in a population of clams from both sites. The results show that gametogenesis occurred from March to December in clams from both sites. Nevertheless, spawning and emission of gametes were synchronized in both sexes from only the clams of the reference site. Although this species is considered as gonochoristic, 6.6% of hermaphroditic cases were observed in clams from both sites in which gametes of both males and females were in ripe stage. Moreover, the period of ripening of sexual products led to an increase of condition index and to a decrease of Cd concentrations in the whole soft tissues of clams from both sites, hence reflecting the phenomenon of "biological dilution".     

Cadmium and copper contents in a freshwater fish species (brook trout, Salvelinus fontinalis) from the subantarctic Kerguelen Islands

The subantarctic Kerguelen Islands (49°S, 70°E) contain freshwaters among the most isolated in the world from direct human activities. Cadmium and copper concentrations were analyzed in muscle and liver tissues of 57 non-migratory brook trout (Salvelinus fontinalis) inhabiting the Sud River of Kerguelen Islands. The mean cadmium concentration in liver was 1.13 μg/g dry wt, within the range of levels measured in liver of marine fish from the Southern Ocean. Muscular Cd levels (0.12 μg/g dry wt) were roughly ten times higher than those measured in Kerguelen’s marine fish species. Copper levels were very high in the two organs (62.27 μg/g dry wt in liver and 3.02 μg/g dry wt in muscle) compared to those detected in fish from the Southern Ocean. Regarding the seasonal trend, the highest Cu and Cd muscular levels were measured in fish at the end of the austral winter, whereas the highest hepatic levels were observed at the end of the austral summer. Moreover, hepatic cadmium levels were higher in females than in males. These results could be related to brook trout spawning physiological preparations and foraging behavior during the summer period. We provide here the first results about Cu and Cd levels in liver and muscle of a freshwater fish species in an insular subantarctic context. They are in agreement with the high cadmium contamination found in fish of the Southern Ocean.