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.     

Monitoring metals in the population living in the vicinity of a hazardous waste incinerator

This study is a part of a monitoring program for the determination of metals in various human tissues of the population living in the vicinity of a new hazardous waste incinerator (HWI) in Constantí (Tarragona County, Spain). Concentrations of arsenic (As), beryllium (Be), cadmium (Cd), chromium (Cr), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb), tin (Sn), thallium (Tl), and vanadium (V) were determined in brain, bone, kidney, liver, and lung autopsy samples collected in 2003 from 22 individuals who had been living for at least 10 yr in the area under evaluation. Results were compared with the metal levels obtained in a baseline study, which was performed during the construction of the HWI (1996–1998). In the present survey, As, Be, Tl, and V levels were not detected in any of the analyzed tissues, while Cr concentrations were very close to the limit of detection. The highest levels of Cd and Hg were found in kidney (17.46 μg/g and 0.23 μg/g, respectively), those of Mn in liver (1.07 μg/g), and those of Ni, Pb, and Sn in bone (1.16 μg/g, 2.11 μg/g, and 0.34 μg/g, respectively). In comparison to the results of the baseline study, a general reduction of most metal concentrations was observed in the current survey.     

Characterization and Distribution of the Selected Metals in the Scalp Hair of Cancer Patients in Comparison with Normal Donors

Eighteen metals were estimated in the scalp hair samples from cancer patients (n = 111) and normal donors (n = 113). Nitric acid–perchloric acid wet digestion procedure was used for the quantification of the selected metals by flame atomic absorption spectrophotometry. In the scalp hair of cancer patients, highest average levels were found for Ca (861 μg/g), followed by Na (672 μg/g), Zn (411 μg/g), Mg (348 μg/g), Fe (154 μg/g), Sr (129 μg/g), and K (116 μg/g), whereas in comparison, the dominant metals in the scalp hair of normal donors were Ca (568 μg/g), Zn (177 μg/g), Mg (154 μg/g), Fe (110 μg/g), and Na (103 μg/g). The concentrations of Ca, Cd, Co, Cr, Fe, K, Mg, Mn, Na, Ni, Pb, Sb, Sr, and Zn were notably higher in the hair of cancer patients as compared with normal donors, which may lead to a number of physiological disorders. Strong positive correlations were found in Mn–Pb (0.83), Cd–Cr (0.82), Cd–Li (0.57), Fe–Pb (0.56), and Fe–Mn (0.55) in the hair of cancer patients whereas Na–Cd, Li–Cr, Li–Co, Co–Cd, Li–Cd, Na–Co, Na–Li, Ca–Mg and Na–Cr exhibited strong relationships (r > 0.50) in the hair of normal donors. Principal Component Analysis (PCA) of the data revealed seven PCs, both for cancer patients and normal donors, but with significantly different loadings. Cluster Analysis (CA) was also used to support the PCA results. The study evidenced significantly different pattern of metal distribution in the hair of cancer patients in comparison with normal donors. The role of trace metals in carcinogenesis was also discussed.     

Copper, zinc, iron, and manganese accumulation in cattle from Asturias (northern Spain)

Monitoring levels of mineral concentrations in animal tissues is important for assessing the effect of contamination on animal health and safety of animal origin products in human nutrition. This study evaluated the levels of certain trace elements (copper, zinc, iron, and manganese) in cattle from an industrial and mining region in the north of Spain (Asturias). Samples of 312 animals aged 9–12 mo were collected from the whole region and analyzed after acid digestion using atomic absorption spectrophotometry (AAS). The geometric mean concentrations obtained per wet weight for the liver, kidney, muscle, and blood were 34.3 mg/kg, 4.04 mg/kg, 1.65 mg/kg, and 0.651 mg/L for copper, respectively, and 38.5 mg/kg, 23.0 mg/kg, 47.0 mg/kg, and 2.44 mg/L for zinc, respectively. For iron, blood was not analyzed and results were 96.2 mg/kg, 105 mg/kg, and 56.0 mg/kg for the liver, kidney and muscle, respectively. For manganese, only the liver and kidney were analyzed, and the results were 3.11 mg/kg and 1.19 mg/kg, respectively. There was no evidence of an accumulation of toxic levels of trace metals in Asturian cattle. Females accumulated more iron in the liver (p<0.001, F _1,310=18.4) and the kidney (p<0.001, F _1,310=13.5) and more manganese in the liver (p<0.01, F _1,310=9.55) than males.     

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.     

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.     

Accumulation of Cd and Pb in successive stages ofGalleria mellonella and metal transfer to the pupal parasitoidPimpla turionellae

Larvae ofGalleria mellonella L. (Lepidoptera, Pyralidae) were exposed to Pb (4, 43, 430 μg Pb/g food dw) and Cd (4, 20, 40 μg Cd/g food dw) applied singly and in combination. Metal transfer of Pb and Cd was investigated from food to larvae and successive stages ofG. mellonella and also to the pupal parasitoidPimpla turionellae L. (Hymenoptera, Ichneumonidae). Larvae/food concentration factors (CFs) were highest in controls (Cd 5.25, Pb 3.07) and ranged from 0.19 to 0.92 for Cd and from 0.18 to 0.83 for Pb in contaminated groups; in general, the CFs decreased with an increasing contamination level in food.G. mellonella eliminated most of its larval metal load before pupation (metal concentration in larvae ς> pupae). Although pupae were only moderately contaminated (0.11–1.61 μg Cd/g dw), concentrations inP. turionellae ranged from 0.5 to 6.8 μg Cd/g dw. Again, CFs (parasitoid/pupa) decreased with enhanced levels of metal in the host pupae (Cd 3.07–14.05, Pb 0.0–2.47). The CFs calculated for both species were lower at combined contamination compared to single application.G. mellonella can be classified as a ‘deconcentrator’ (CF<1) along with other lepidopteran species, whereasP. turionellae is apparently a ‘macroconcentrator’ (CF>2).     

Accumulation of cadmium, lead and strontium, and a role of calcium oxalate in water hyacinth tolerance

Eichhornia crassipes plants brought from the River Nile were cultured in jars containing river water supplemented with various concentrations of Cd, Pb, and Sr (0 to 100 μg cm-3), added simultaneously. Treatment continued for 20 d during which each cultivation solution was being replaced with fresh one every 3 d. The growth of Eichhornia was drastically retarded at heavy metal concentrations higher than 15 μg cm-3. At concentrations 15 or 25 μg cm-3, the accumulation of Cd and Pb to levels several times higher than those in control plants was found. More than 50 % of the uptaken metals were retained by roots alone. Leaves and leaf petiols received around 30 and 20 % of the accumulated metals, respectively. X-ray microanalysis indicated the presence of the three heavy metals in Ca oxalate crystals. Content of metals in the crystals increased progressively over time of exposure in a way similar to those in whole plant tissues. These results suggest a possible role for Ca oxalate crystalization in toxic heavy metal deposition and thus tolerance by Eichhornia. This revised version was published online in August 2006 with corrections to the Cover Date.     

Induction of metallothionein in rat tissues following subchronic exposure to mercury shown by radioimmunoassay

Although the analysis of metallothionein (MT) by radioimmunoassay (RIA) is not a common technique, its use is preferred over other methods since it offers the advantages of sensitivity and specificity. In this paper we present data on the basal levels of MT in rat tissues and physiological fluids of female Sprague-Dawley rats. The mean basal MT concentrations of the following organs and fluids were determined by RIA to be: liver (9.8 μg/g), kidney (68 μ/g), brain (0.8 μg/g), spleen (1.0 μg/g), heart (5.4 μg/g), plasma (11 ng/ml), and urine (200–300 μg/g creatinine). Following subcutaneous exposure to inorganic mercury (0.2 μmol/kg/d, 5 d a week for up to 4 wk), the metal accumulated primarily in the kidney. There was also a simultaneous accumulation of zinc in the liver and of zinc and copper in the kidney. Induction of MT did take place in liver, kidney, brain, and spleen. No increases in the MT contents of blood and urine were noted. The excess zinc and copper in the kidney of exposed animals were found to be associated predominantly with MT. No overt signs of mercury toxicity were noted in these animals and the incidence of proteinurea was nil. The data are discussed with reference to methods of MT determination in animal tissues and in relation to mercury metabolism and toxicity.     

Maternal and neonatal scalp hair concentrations of zinc, copper, cadmium, and lead

Postpartum scalp hair samples from 82 term-pregnancy mother/neonate pairs were analyzed for their concentration of zinc (Zn), copper (Cu), cadmium (Cd), and lead (Pb), using inductively coupled plasma-mass spectrometry. Maternal and neonatal Zn concentrations had geometric means (and 99% confidence intervals) of 122.5 μg/g (117.9–131.5 μg/g) and 146.9 μg (141.5–156.7 μg/g) respectively. Corresponding Cu values were 18.4 μg/g (17.6–23.8 μg/g) and 6.7 μg/g (6.3–7.6 μg/g). Those of Cd were 0.49 μg/g (0.47–0.69 μg/g) in the mothers and 0.57 μg/g (0.55–0.86 μg/g) in the neonates. For Pb, they were 7.95 μg/g (7.60–9.32 μg/g) and 4.56 μg/g (4.39–5.56 μg/g). Cigaret smoking, despite its relatively low prevalence (19.5%), was associated with lower Zn and higher Cd and Pb concentrations and in lower Zn/Cd and Zn/Pb molar concentration ratios. Smoking also altered interelemental relationships, particularly those of Zn with Cd and Pb and those between Cd and Pb. Smoking frequency appeared to show negative dose-response effects on maternal and neonatal Zn concentrations, Zn/Pb molar concentration ratios, and birth weight. Mothers with a history of oral contraceptive (OC) usage had significantly higher Cu concentrations and lower Zn/Cu molar concentration ratios than nonusers, with the highest Cu concentrations and lowest Zn/Cu values being associated with third-generation OCs. No similar effects were elicited in the respective neonatal Cu concentrations. Neither alcohol consumption nor prenatal supplementation with iron and/or folic acid had discernible effects on the maternal or neonatal elemental concentrations. The data from this study suggest that in a given population of term-pregnancy mothers and neonates, significant interindividual variations in hair trace element concentrations can occur, irrespective of commonality of general environment, and that lifestyle factors, including cigaret smoking and OC usage history, can be significant contributory factors to such variations. The data are discussed in relation to the effects of smoking-associated exposure to Cd and Pb exposure on Zn availability for placental transfer, as well as on the quantitative maternal Zn supply levels to the fetus resulting from the known tendency of smokers to have lower dietary intakes of Zn. The higher Cu concentrations in OC users are discussed in relation to altered Cu metabolism, characterized by increased synthesis of the Cu-binding protein, ceruloplasmin, as an acute-phase antioxidant response to altered lipid profile and increased lipid oxidation.     

Comparison of Trace Elements in the Scalp Hair of Malignant and Benign Breast Lesions Versus Healthy Women

Trace elements including Al, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sb, Sr, and Zn were analyzed in the scalp hair samples of women with malignant breast lesions, women with benign breast lesions, and healthy donors using atomic absorption spectrophotometric method. In the scalp hair of malignant-tumor patients, the highest average concentration was shown by Ca (1,187 μg/g), followed by Na (655 μg/g), Mg (478 μg/g), Zn (391 μg/g), Sr (152 μg/g), Fe (114 μg/g), and K (89.8), while in the case of benign-tumor patients, the average estimated element levels were 1,522, 1,093, 572, 457, 217, 80.4, and 74.7 μg/g, respectively. Most of the elements exhibited non-normal distribution evidenced by large spread, standard error, and skewness values. Mean concentrations of Ca (634 μg/g), Zn (206 μg/g), Mg (162 μg/g), Fe (129 μg/g), and Na (82.1 μg/g) were noteworthy in the scalp hair of healthy women. Average levels of Na, Sr, K, Cd, Co, Pb, Mg, Ca, Zn, Ni, Sb, and Mn were revealed to be significantly higher in the hair of malignant and benign patients compared to the healthy women; however, Fe, Cu, Al, and Cr were not significantly different in the scalp hair of the three groups. The quartile distributions of Ca, Cd, Co, Cr, K, Mg, Mn, Na, Ni, Pb, Sb, and Sr revealed maximum spread in the scalp hair of malignant and benign groups; nevertheless, Al, Cu, Fe, and Zn exhibited almost comparable quartile levels in the three groups. Strong correlation coefficients were found between Fe and Cd, Al and Na, Mn and Sr, Co and Cr, Cd and Cr, Pb and K, Pb and Mn, Cu and Na, and Al and Fe in the scalp hair of malignant-tumor patients, while Fe and K, Cd and Co, Na and Co, and Cr and Pb showed strong correlations in the scalp hair of benign-tumor patients, both of which were significantly different compared with the healthy subjects. Multivariate cluster analysis also revealed divergent clustering of the elements in the scalp hair of malignant and benign patients in comparison with the healthy women.     

Determination of ergot alkaloids in feed by HPLC

A HPLC method for the determination of ergometrine, ergotamine, ergocristine, α-ergocryptine and ergocornine in cereals for animal feed and in mixed feed with high cereal content was developed. Samples were extracted under acidic conditions using a mixture of phosphoric acid and acetonitrile, the extract purified with solid phase extraction cartridges (strong cation exchange), and ergot alkaloids detected after gradient elution on a C18 column by HPLC with fluorescence detection. Detection and determination limits for each individual alkaloid were at 5 (μ/kg and 10 (μg/kg, respectively. With this method, high recovery (82–120%) and good reproducibility was achieved for wheat, rye and mixed feeds, at a sum of total determined alkaloids of < 500 (μg/kg. This method was used to analyse Bavarian feeds (n=124) over three years (2005–2007), and ergot alkaloids were detected in 91 % of the samples. The majority of positive samples had ergot alkaloid contents of < 250 μg/kg, the median alkaloid level was at 70 (μg/kg. The maximum sum of total determined alkaloids exceeded 1000 (μg/kg in wheat, triticale, rye, and mixed feeds, the highest result was obtained for mixed feed (4880 (μg/kg). Parts presented at the Feed Safety Conference, Namur, Belgium, Nov 27–28, 2007     

Analysis of cadmium and lead in mice organs

Analysis and distribution of Pb and Cd in different mice organs, including the liver, kidney, spleen, heart, and blood, were evaluated before and after treatment with different aqueous concentrations of Nigella sativa (1.25–10.0 mg/L). Atomic absorption spectrometry was used for analysis of Pb and Cd in these organs. Results indicated that the Pb in the unexposed group of mice without treatment with N. sativa (black cumin) was in the following order: liver>heart>spleen>kidney, and the distribution of Pb in various organs of the unexposed group was not affected significantly by N. sativa. Moreover, results of mice exposed for Pb show that the Pb concentrations in different organs were reduced significantly (p<0.05) by 72.9%, 63.4%, 72.3%, 66.7%, and 39.5% at a dose of 10 mg/L of N. sativa for the liver, kidney, heart, spleen, and blood, respectively. Furthermore, the distribution of Cd in the unexposed Cd group of mice without treatment with N. sativa was in the following order: kidney>heart>spleen>liver. Nigella sativa at 10 mg/L reduced Cd levels in mice exposed to Cd by 75.5%, 83.3%, 47.0%, 95.3%, and 100% in the liver, kidney, heart, spleen, and blood, respectively, whereas blood Cd concentrations were lowered to below the detection limit of 0.05 μg/L. A 28-d exposure of mice to a Cd−Pb mixture at a concentration of 1 ppm in drinking water induced a highly significant inhibition (p<0.0001) of antibody response to human serum (80.5%). The suppressed immune responses in mice pretreated with the Cd−Pb mixture were reversed by 43.1% and 38.9% in the presence of 1.25 and 2.5 mg/mL of N. sativa, respectively, whereas higher concentrations (5–10 mg/mL) of N. sativa increased the immunosuppression significantly. Nigella sativa at 1.25–10 mg/mL did not induce any significant modulation of the antibody response in unexposed mice.     

Plasma molybdenum concentrations in children with and without phenylketonuria

Plasma molybdenum concentrations were determined in children, ages two to 12 yr, with and without phenylketonuria (PKU). Mean plasma molybdenum concentrations did not differ significantly between the children with PKU (1.33±0.5 μg/L) and without PKU (1.75±0.8 μg/L). Plasma molybdenum concentrations in both groups of children ranged from <1 to 3 μg/L. When data from all children were combined and then separated based on gender, mean plasma molybdenum levels did not differ significantly between 9 females (1.56±0.68 μg/L) and 12 males (1.58±0.76 μg/L). Data were also combined and mean (±SD) plasma molybdenum concentrations calculated for age groups. Two children aged 1 to <4 yr had plasma molybdenum concentrations of 1.0 μg/L, and six children aged 4 to <7 yr had mean (±SD) plasma molybdenum concentrations of 1.5±0.8 μg/L. Eleven children aged 7 to <11 yr had a mean plasma molybdenum concentration of 1.7±0.7 μg/L, and two children 11 to <14 yr had plasma molybdenum concentrations of 1 μg/L and 2 μg/L. Plasma molybdenum concentrations did not differ significantly among children in the age groups.     

Selenium status inCharadriiformes

The distribution of selenium in a marine wader, the Oystercatcher (Haematopus ostralegus) is given by the levels in 15 tissues and plasma. Red blood cells (RBC) contain the highest level (23 mg/kg dry wt) followed by liver, lung, and kidney (17–19 mg/kg). Most other tissues range from 3–10 mg/kg. The average kidney and liver concentrations of the Oystercatcher belong to the concentrations characteristic in birds. However, the Oystercatcher's tissue selenium concentrations are in general four-to fivefold mammalian levels, but in liver and lung, 11- to 13-fold and in the RBC, 12- to 33-fold. The selenium plasma and RBC levels of the Oystercatcher vary during the year from 280 to 410 μg/L and 13 to 30 mg/kg dry wt, respectively; the plasma concentrations are positively correlated with the RBC selenium concentrations. An overview of literature data shows that the selenium kidney and liver concentrations of birds do not vary with geographical latitude and size (length) of the birds. In species of the ordersCharadriiformes andProcellariiformes, high selenium kidney, and to a lesser extent liver, concentrations may occur. A function of selenium in antioxidation is suggested.     

Trace Metals (Cd,Co, Cr,Cu, Hg,Ni, Pb,and Zn) in Food Supplements of Marine Origin

We determined the concentrations of Cd, Co, Cr, Cu, Hg, Ni, Pb, and Zn in dietary supplements of marine origin. Four supplement categories were studied; algae, coral, krill, and shark cartilage. A direct mercury analyzer was used for Hg determinations while acid digestions and ICP-AES were used for Cr analysis and ICP-MS for the other trace metals. Algae are the supplements showing the highest concentrations of Pb, Cr, and Ni with respective means of 1.6 mg Pb/kg dry weight (d.w.), 3.2 Cr mg/kg d.w., and 8.0 mg Ni/kg d.w. Krill supplements have the highest levels of Cd, Cu, and Zn with 0.65 mg Cd/kg d.w., 63 mg Cu/kg d.w., and 50 mg Zn/kg d.w., respectively. Shark cartilage supplements show the highest levels of Hg and Co with mean concentrations of 160 μg Hg/kg d.w. and 73 ± 51 μg Co/kg d.w., respectively. No samples in our study exceeded the provisional tolerable daily intakes set by Health Canada, the joint committee of the World Health Organization/Food and Agricultural Organization, or the U.S. Environmental Protection Agency. Nevertheless, Ni and Pb in algae and Hg in shark cartilage may end up contributing to a very significant portion of the allowable daily intake—leaving little room for normal intake through food consumption and other exposure pathways.     

Natural occurrence of zeralenone in feeds and feedstuffs used in poultry and pig nutrition in colombia

A total of 200 samples of feedstuffs and mixed feeds used for poultry and pig nutrition in Colombia were analysed for zearalenone using a LC technique with a limit of detection of 20 μg/kg. Samples of grain sorghum, maize, processed soybean, rice meal, cottonseed meal, and poultry and pig feeds, representative of the Colombian production for the 1995–1996 harvest, were taken at feed manufacturing plants located in different cities of the country. Zearalenone was detected in 25 of 45 samples of sorghum, 2 of 33 samples of maize, 7 of 22 samples of rice meal, 9 of 17 samples of cottonseed meal, 11 of 30 samples of poultry feed and 6 of 16 samples of pig feed. Zearalenone was not detected in soybean or other feedstuff s analysed (wheat by- products, cassava meal, palm). Overall levels of zearalenone ranged from 29 to 3956 μg/kg, with a mean value of 436 μg/kg. Only one of the 6 positive samples of pig feed had a zearalenone concentration above 500 μg/kg, which is normally considered as the safe level for pigs.     

Revisiting copper and cobalt concentrations in supposed hyperaccumulators from SC Africa: influence of washing and metal concentrations in soil

Metal concentrations have been determined in shoots of 12 species considered as Cu and/or Co hyperaccumulators, collected from five subpopulations in a Cu/Co mine in Katanga. Samples have been subjected to three cleansing protocols (water, alconox, alconox + EDTA). Cu/Co concentrations were significantly higher when demineralised water was used to wash samples compared to more aggressive solutions. Washing effect was largest for species with velvety (Acalypha cupricola) or sticky (Haumaniastrum katangense) indumentum. Element concentrations in shoots varied by two orders of magnitude, i.e. 45–2,891 mg kg⁻¹ Cu (median: 329 mg kg⁻¹) and 21–1,971 mg kg⁻¹ Co (median: 426 mg kg⁻¹) and were generally lower than previously published values. Only 9.3% of data exceeded the hyperaccumulation threshold (1,000 mg kg⁻¹) for Cu and 13% for Co. Shoot concentrations varied by up to two orders of magnitude among subpopulations within species which was partly explained by variation of metal concentrations in the soil. Although the species considered in this paper undisputedly accumulate Co and Cu up to very high concentrations that require specific shoot tolerance mechanisms, the concept of hyperaccumulation, as defined for other metals like Zn and Ni, needs to be critically re-examined for Cu and Co. Our results suggest that many species so far regarded as Co/Cu hyperaccumulators might eventually turn out to be indicators.     

Evaluation of trace metals in sediment,water, and fish (Mugil cephalus) of the central Black Sea coast of Turkey

In this study, concentrations of trace metals such as As, Cd, Cu, Cr, Fe, Pb, Ni, Sn, Se, and Zn were determined in sediments, water, and a kind of fish (Mugil cephalus) of the central Black Sea coasts by employing Inductively Coupled Plasma Mass Spectrometry and microwave digestion technique. Gill, muscle, liver, and other tissues were analyzed separately for each sample. The accuracy of the results were checked by using a certified reference material (DORM-4). In water samples, the metal determined at highest concentrations was Cu (1645.44 µg/L). In sediment samples, the metal determined at highest concentrations was Fe (12223.50 mg/kg). The levels of trace metals found in the different parts of the fish were: Zn in muscle tissue (30393.28 mg/kg), Sn in gill tissue (5140.08 mg/kg), and Cu in liver tissue (289.31 mg/kg). These results were also compared with various relevant guidelines and literature.     

Trace Elements and Metallothionein in Liver and Kidney of <Emphasis Type="Italic">Felis catus</Emphasis>

Trace metals such as Zn, Cu, and Fe are essential for life; differently, no biochemical function is known for Cd. Changes in dietary metal concentrations can cause deficiency or toxicity. Studies on trace elements in cat are lacking. This paper aimed to analyze Zn, Cu, Fe and Cd concentrations in liver and kidney of pathological domestic cat and to isolate metallothionein (MT) in these tissues. It was not possible to explore a possible correlation between metal concentrations and pathologies because the incidence for each of them was too low. Fe was the most abundant metal; in particular, the liver accumulates average Fe concentrations one order of magnitude higher than Zn and Cu, ranging from 66.75 and 1,444.23 μg/g. Significantly, higher levels of Fe were found in the liver of elder animals. Zn concentrations varied between 26.31 and 84.78 μg/g in the liver whereas in the kidney, ranged between 7.69 and 71.15 μg/g. Cu concentrations were between 2.37 and 112.91 μg/g in liver and between 2.12 and 9.85 μg/g in kidney. Cd was the least abundant metal with the exception of the kidney of the oldest cats where it reached a maximum of 13.71 μg/g. Gel-filtration metal distribution profiles from cytosolic extracts revealed the presence of Cd, Cu, Zn thioneins either in the liver or in the kidney. Because tissue samples were taken from pathological cats from different breed and age, care must be taken to use these data as a baseline profile of trace elements in healthy animals. Our results are indicative that for some specimens the feed levels of Fe and Cu could be higher than the optimal dietary intake and in few cats, there was also an exposure to Cd that was counteracted by MT biosynthesis.