Trace element concentrations in skin of free-ranging bottlenose dolphins (Tursiops truncatus) from the southeast Atlantic coast

Concentrations of trace elements (Al, As, Ba, Be, Cd, Co, Cr, Cu, Fe, Li, Mn, Ni, Pb, Sb, Se, Sn, Tl, U, V, Zn) and total mercury (THg) were determined in skin samples collected from free-ranging bottlenose dolphin (Tursiops truncatus) populations. Dolphins were captured in the estuarine waters of Charleston (CHS), South Carolina (n=74) and the Indian River Lagoon (IRL), Florida (n=75) during 2003, 2004 and 2005. A subset of the skin tissue samples were used to determine methylmercury (MeHg) levels in CHS (n=17) and IRL (n=8) bottlenose dolphins. Distributions of trace element concentrations by age (adult vs. juvenile), gender (male vs. female) and study area (CHS vs. IRL) were examined. In general, higher elemental skin concentrations were found in CHS adult males than those of IRL adult males, except for THg and MeHg. For CHS dolphins, adult females showed significantly higher THg levels than juvenile females while higher Mn levels were found in juvenile females. For IRL dolphins, adult males showed significantly higher As concentrations than that in juvenile males and females while higher Co and V levels were found in juvenile males than adult males. Of all elements measured in this study, significantly higher levels of Fe, Se and Zn concentrations in skin tissue of both dolphin populations were similar to other studies reported previously. Percentage of MeHg/THg in skin tissue of CHS and IRL dolphin was about 72% and 73%, respectively. Dietary levels of trace elements may play an important role in contributing to concentration differences for As, Co, Mn, Sb, Se, THg and Tl between CHS and IRL dolphins. Total Hg concentrations were significantly correlated with the age of CHS dolphins, while an inverse relationship was detected for Cu, Mn, Pb, U and Zn. The only significant correlation found between trace element concentration and IRL dolphins' age was Mn. Geographic differences in several trace element concentrations (As, Co, Mn, Sb, Se, THg and Tl) in skin tissue may be potentially useful to discriminate between dolphin populations and is a possibility that warrants further investigation.     

Heavy metals in soft tissues of Tursiops truncatus and Delphinus delphis from west Atlantic Ocean by X-ray spectrometry

In this work, the concentration of heavy metals in muscle, liver, fat tissue and skin is studied in 15 Delphinus delphis and two Tursiops truncatus dolphins, stranded along the Portuguese coast of the Atlantic Ocean. Sample collection was performed post-mortem and the tissues were kept frozen until analysed. Sample preparation included lyophilising and grounding in a Teflon mill to avoid contamination by metals. The obtained powder was prepared as pellets for each sample and analysed directly by X-ray fluorescence spectrometry. The concentrations of K, Ca, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Hg and Pb were obtained. Significant differences between the muscle, the skin and the fat tissues were detected. Cobalt concentrations were similar in liver, skin and muscle. The levels of Ni, Rb and Sr are at the level of the detection limit and whenever measurable are rather constant in all the analysed tissues. The results show that the highest concentrations of Mn, Cu and Hg are always in liver tissues. Zinc and Se concentrations are higher in skin and Pb is present in very low concentrations in all the analysed tissues except in skin; Fe and As are enhanced in muscle and liver. In general, the two studied species did not seem to differ significantly in their heavy metals concentration in a given tissue.     

Metals and selenium in the liver and bone of three dolphin species from South Australia, 1988-2004

Metal and selenium concentrations (wet weight) were determined in the liver (Cd, Hg, Pb, Zn, Cu and Se) and bone (Pb and Cd) of common dolphins (Delphinus delphis, N=71) and bottlenose dolphins (Tursiops truncatus, N=12, and Tursiops aduncus, N=71) stranded or by-caught in South Australia from 1988 to 2004. Differences in metal burdens existed between species, stranding location, and relative age. T. aduncus had the greatest mean tissue burdens of liver Pb (0.45 mg/kg), Cd (6.45 mg/kg), Hg (475.78 mg/kg), Se (178.85 mg/kg) and Zn (93.88 mg/kg) and bone Pb (2.78 mg/kg), probably reflecting their coastal habitat and benthic prey. Mean Cu was highest in T. truncatus (21.18 mg/kg). Bone Cd was measured only in T. aduncus and averaged 0.05 mg/kg. Stranding location impacted metal burdens. Dolphins from Spencer Gulf had higher mean levels of liver Pb (0.39 mg/kg) while Gulf St Vincent dolphins had greater liver Hg (444.64 mg/kg), liver Se (163.12 mg/kg), and bone Pb (2.85 mg/kg). This may be due to high anthropogenic inputs of Pb and Hg into Spencer Gulf and Gulf St Vincent respectively. Liver Cd, Hg, Se and Pb increased with age in all species while Cu decreased with age, in keeping with previous studies. Se and Hg were positively correlated. The possibility that metallothioneins are driving observed correlations between Zn, Cd, Hg and Cu are discussed. Future research must investigate the toxicological consequences of the metal concentrations reported.     

Heavy metals in the tissues of common dolphins (Delphinus delphis) stranded on the Portuguese coast.

The concentrations of Hg, Sn, Cr, Zn, Ni, Co, Cd, Mn, Fe and Cu were determined in the liver, kidney and muscle of 24 common dolphins stranded on the Portuguese coast between 1995 and 1998. Nitric acid was used to extract the metals from the tissues for analysis by inductively-coupled plasma/atomic emission spectroscopy (ICP/AES). Those metals with relatively higher concentrations included Fe, Zn and Hg, particularly in liver. Other metals including Cr, Ni and Cd tended to show much lower levels, or were even undetected (e.g. Co). Different metals seemed to show different temporal trends, although due to substantial variations of the mean concentrations for each year obtained, such temporal pattern has to be studied further. Total Hg concentration in the kidney, muscle and particularly liver, were higher in females than in males. Total Hg concentrations in all the organs increased with body length of dolphins, whilst those of Zn and Cu in muscle decreased with dolphin length. A strong correlation was found between essential metals Zn and Cu in muscle, possibly resulting from sequestration of these metals by metallothionein. In addition, significant co-associations existed between the same metal (e.g. Hg, Sn and Zn) in different organs.     

Metals contained and leached from rubber granulates used in synthetic turf areas

The aim of this study was to quantify metals contained in and leached from different types of rubber granulates used in synthetic turf areas. To investigate the total content of metals, ca 0.5 g of material was added with HNO₃, HF and HClO₄ and microwave digested with power increasing from 250 W to 600 W. Leachates were prepared by extraction of about 5.0 g of material at room temperature for 24 h in an acidic environment (pH 5). Leaching with deionized water was also performed for comparison. Aluminium, As, Ba, Be, Cd, Co, Cr, Cu, Hg, Fe, Li, Mg, Mn, Mo, Ni, Pb, Rb, Sb, Se, Sn, Sr, Tl, V, W and Zn were quantified by high-resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) and ICP optical emission spectrometry (ICP-OES).Results indicated that the developed method was accurate and precise for the multi-element characterization of rubber granulates and leachates. The total amount and the amount leached during the acidic test varied from metal to metal and from granulate to granulate. The highest median values were found for Zn (10,229 mg/kg), Al (755 mg/kg), Mg (456 mg/kg), Fe (305 mg/kg), followed by Pb, Ba, Co, Cu and Sr. The other elements were present at few units of mg/kg. The highest leaching was observed for Zn (2300 μg/l) and Mg (2500 μg/l), followed by Fe, Sr, Al, Mn and Ba. Little As, Cd, Co, Cr, Cu, Li, Mo, Ni, Pb, Rb, Sb and V leached, and Be, Hg, Se, Sn, Tl and W were below quantification limits. Data obtained were compared with the maximum tolerable amounts reported for similar materials, and only the concentration of Zn (total and leached) exceeded the expected values.     

The use of lichen (Cetraria nivalis) and moss (Rhacomitrium lanuginosum) as monitors for atmospheric deposition in Greenland

Concentrations of Pb, Cd, Hg, Zn, Cu, Cr, Ni, As, V, Al and Fe are reported from soil, humus, moss (Rhacomitrium lanuginosum) and lichen (Cetraria nivalis) sampled at four locations in Greenland. For Al, Fe, Cr and V the levels in soil were highest followed by humus and R. lanuginosum and with the lowest levels in C. nivalis. The same was true for Pb, Cu and Ni but without as great a difference between medias. For Cd and Hg, the lowest levels were found in soil. For Zn and As, the media with highest levels differed between locality. Data were examined by a principal component analysis. Three principal components explained 87% of the total variation. The dominant elements in the first component were Fe, Al, V, Ni, Cr, Cu and Pb. This component is interpreted as a soil dust factor. The concentrations in R. lanuginosum and C. nivalis of these elements are believed to be highly influenced by soil dust. Pb concentrations in moss and lichen may also be influenced by other sources as Pb also had some correlation's with the third component. Zn and Cd and to a lesser extent. As were the dominant elements in the second component. The third component was highly dominated by Hg with a lesser influence of Pb and As, Zn, Cd and Hg concentrations in R. lanuginosum and C. nivalis are believed to be influenced by other sources than soil dust which may be long-range atmospheric transport. In general, both the within locality and the between locality variability in the values of the three components decreased in the order soil, humus, R. lanuginosum and C. nivalis. The lichen C. nivalis is looked at as an indicator with greater potential for monitoring atmospheric deposition of elements than the moss R. lanuginosum.     

Selenium in soils,spermatophytes and bryophytes around a Zn-Pb smelter,New South Wales,Australia

Blood and serum samples from 372 15-year-old adolescents were collected in two cities in Sweden and analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The objective was to (1) determine the levels of 13 elements in blood and serum from the teenagers; and (2) for each element, investigate the correlation between the concentrations in blood and serum. The concentrations in blood and serum were generally in line with that usually reported for the essential elements Co, Cu, Zn and Se, and generally low for the 'non-essential' elements Cd, Hg, Pb. The median concentrations were in blood and serum, respectively: of Co 0.31 and 0.48 microg/l, Cu 0.92 and 1.0 mg/l, Zn 6.1 and 0.99 mg/l, Se 110 and 100 microg/l, Rb 2.8 and 0.24 mg/l, Hg 1.1 and 0.44 microg/l, Pb 16 and 0.33 microg/l. The median concentration of W in blood was <0.2 microg/l (below the detection limit) and in serum 0.087 microg/l. The median concentrations of Cd, Rh, Pd, Pt and Tl were below the detection limits. Statistically significant correlations were found between the concentrations in blood and serum for Co, Cu, Zn, Se, Rb, W, Hg and Pb. The levels presented in this study constitute baseline levels or levels generally not exceeded in adolescents for 13 elements, including essential, ubiquitous toxic, and rare elements.     

Life history as a source of variation for persistent organic pollutant (POP) patterns in a community of common bottlenose dolphins (Tursiops truncatus) resident to Sarasota Bay, FL

As apex predators within coastal ecosystems, bottlenose dolphins (Tursiops truncatus) are prone to accumulate complex mixtures of persistent organic pollutants (POPs). While substantial variations in POP patterns have been previously observed in dolphin populations separated across regional- and fine-scale geographic ranges, less is known regarding the factors influencing contaminant patterns within localized populations. To assess the variation of POP mixtures that occurs among individuals of a population, polychlorinated biphenyl (PCB), organochlorine pesticide (OCP) and polybrominated diphenyl ether (PBDE) concentrations were measured in blubber and milk of bottlenose dolphins resident to Sarasota Bay, FL, and principal components analysis (PCA) was used to explain mixture variations in relation to age, sex and reproductive maturity. PCA demonstrated significant variations in contaminant mixtures within the resident dolphin community. POP patterns in juvenile dolphins resembled patterns in milk, the primary diet source, and were dominated by lower-halogenated PCBs and PBDEs. A significant correlation between principal component 2 (PC2) and age in male dolphins indicated that juvenile contaminant patterns gradually shifted away from the milk-like pattern over time. Metabolically-refractory PCBs significantly increased with age in male dolphins, whereas PCBs subject to cytochrome p450 1A1 metabolism did not, suggesting that changes in male POP patterns likely resulted from the selective accumulation of persistent POP congeners. Changes to POP patterns were gradual for juvenile females, but changed dramatically at reproductive maturity and gradually shifted back towards pre-parturient profiles thereafter. Congener-specific blubber/milk partition coefficients indicated that lower-halogenated POPs were selectively offloaded into milk and changes in adult female contaminant profiles likely resulted from the offloading of these compounds during the first reproductive event and their gradual re-accumulation thereafter. Overall, these results indicate that significant variations in contaminant mixtures can exist within localized populations of bottlenose dolphins, with life history factors such as age and sex driving individual differences.     

Rapid multielement analysis of oyster and cockle tissue using x-ray fluorescence spectrometry,with application to reconnaissance marine pollution investigations

Forty-two elements in four standard reference materials and oyster and cockle tissue were analysed by the X-ray fluorescence spectrometry (XRF) method. Comparisons between certified values for standard reference materials and those of the authors indicate that XRF is suitable for determining Ba, Br, Cu, Fe, Mn, Pb, Rb, Sr, and Zn in organic matrix. Results for As, Cd, Cr, and Ni indicate that XRF is not reliable when analysing within approximately 2 mg kg⁻¹ of the detection limits for these elements.XRF has been used to show that cockles accumulate Fe, Hg, I, Pb, Sr, Ti and Zn and oysters accumulate Cr, Cu, Fe, La, Ni, Ti, Yb, and Zn in moderately polluted areas. Values for As, Cu, Fe, Hg, Ni, Pb, Ti and Zn have been verified using atomic absorption spectroscopy. Whilst Hg was successfully determined, its limit of detection using XRF (9 mg kg⁻¹) is too high if results are to be compared with the commonly used health standard for Hg in edible marine biota (0.5 mg kg⁻¹ wet wt.). XRF has the capacity however to give an accurate linear response to a broad range of elements in approximately the 0–500 mg kg⁻¹ range and is sensitive to much higher values without further sample manipulation. Hence, XRF has potential to be employed more extensively than is presently the case for elemental monitoring in broad-ranging reconnaissance marine pollution studies.     

Trace element concentrations in blood of harbor seals (Phoca vitulina) from the Wadden Sea

Concentrations of 23 elements (Be, Al, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Mo, Pd, Cd, Sn, Pt, Pb) were evaluated in whole blood samples of live harbor seals (Phoca vitulina) from two different locations in the Wadden Sea, the Lorenzenplate in Germany, and the Danish island R?m?. Elemental blood levels were compared to data from literature of seals, other marine mammals and humans. While homeostatically controlled elements showed no differences, concentrations of As, Cr, Mn, Mo, Se, and V were higher than human levels. Furthermore, animals from both locations showed significant geographical differences in whole blood concentrations of Al, Mn, Cu, and Pt. These findings could be explained by differences in feeding areas. The element pattern was not affected by gender. In conclusion, these findings indicate an impact of the environment on biochemical blood parameters of the harbor seals. The significant differences of elements in blood samples of two groups of seals, which were associated with geographical variations of prey support the use of element pattern in blood as tool for investigation of environmental impact on seals.     

Trace element concentrations in hair of healthy Chinese centenarians

Trace element concentrations, as indicators of micronutrient status of healthy centenarians, have not been widely analyzed. This study aimed to assess trace element concentrations in the hair of healthy centenarians. The effects of gender and age on element concentrations were also investigated. Eleven trace elements (Al, Ba, Cd, Cr, Cu, Fe, Mo, Pb, Se, Sr and Zn) in the scalp hair of 107 healthy Chinese centenarians were examined. The overall reference values (RVs) in mg/kg for the hair concentrations of trace elements in centenarians were as follows: Al, 14.95; Ba, 2.68; Cd, 0.06; Cr, 0.59; Cu, 6.21); Fe, 19.37; Mo, 0.50; Pb, 4.64; Se, 0.37; Sr, 4.84; and Zn, 154.37. Data analysis found that only Cu and Zn concentrations show a normal distribution, and there is no significant difference between males and females in any element except Zn. However, the levels of Al, Cd, Cr, Fe, Mo, Pb decrease and the levels of Ba, Cu, Se, Sr, Zn increase with age in the centenarian cohort. Results also revealed that sufficient Zn and Se concentrations as well as low exposure to heavy metals pollution contribute to the longevity of centenarians. The results imply the possibility of manipulating trace element concentrations, especially Zn and Se concentrations in tissues, as a means for therapeutic modality in geriatric disease.     

Trace elements, PCBs and organochlorine pesticides in New Zealand common dolphins (Delphinus sp.)

Trace elements, polychlorinated biphenyls (PCBs) and organochlorine (OC) pesticide levels were determined in tissues collected from stranded and bycaught common dolphins (Delphinus sp.) from New Zealand waters between 1999 and 2005. The concentrations of mercury (Hg), selenium (Se), chromium (Cr), zinc (Zn), nickel (Ni), cadmium (Cd), cobalt (Co), manganese (Mn), iron (Fe), copper (Cu), tin (Sn), lead (Pb), arsenic (As) and silver (Ag) were determined in blubber, liver and kidney tissue. PCBs (45 congeners) and a range of OC pesticides including dieldrin, hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) and its metabolites DDE and DDD were determined in blubber samples. Cr and Ni were not detected in any of the samples and concentrations of Co, Sn and Pb were generally low. Concentrations of Hg ranged from 0.17 to 110 mg/kg wet weight. Organochlorine pesticides dieldrin, HCB, o,p'-DDT and p,p'-DDE were present at the highest concentrations. Sum DDT concentrations in the blubber ranged from 17 to 337 and 654 to 4430 microg/kg wet weight in females and males, respectively. Similarly, Sigma45CB concentrations ranged from 49 to 386 and 268 to 1634 microg/kg wet weight in females and males, respectively. The mean transmission of SigmaDDTs and ICES7CBs between a genetically determined mother-offspring pair was calculated at 46% and 42%, respectively. Concentrations of organochlorine pesticides determined in the present study are within similar range to those reported for Hector's dolphins (Cephalorhyncus hectori) from inshore New Zealand waters.     

Atmospheric pollution for trace elements in the remote high-altitude atmosphere in central Asia as recorded in snow from Mt. Qomolangma (Everest) of the Himalayas

A series of 42 snow samples covering over a one-year period from the fall of 2004 to the summer of 2005 were collected from a 2.1-m snow pit at a high-altitude site on the northeastern slope of Mt. Everest. These samples were analyzed for Al, V, Cr, Mn, Co, Ni, Cu, Zn, As, Rb, Sr, Cd, Sb, Pb, and Bi in order to characterize the relative contributions from anthropogenic and natural sources to the fallout of these elements in central Himalayas. Our data were also considered in the context of monsoon versus non-monsoon seasons. The mean concentrations of the majority of the elements were determined to be at the pg g(-1) level with a strong variation in concentration with snow depth. While the mean concentrations of most of the elements were significantly higher during the non-monsoon season than during the monsoon season, considerable variability in the trace element inputs to the snow was observed during both periods. Cu, Zn, As, Cd, Sb, and Bi displayed high crustal enrichment factors (EF(c)) in most samples, while Cr, Ni, Rb, and Pb show high EF(c) values in some of the samples. Our data indicate that anthropogenic inputs are potentially important for these elements in the remote high-altitude atmosphere in the central Himalayas. The relationship between the EF(c) of each element and the Al concentration indicates that a dominant input of anthropogenic trace elements occurs during both the monsoon and non-monsoon seasons, when crustal contribution is relatively minor. Finally, a comparison of the trace element fallout fluxes calculated in our samples with those recently obtained at Mont Blanc, Greenland, and Antarctica provides direct evidence for a geographical gradient of the atmospheric pollution with trace elements on a global scale.     

Concentrations of 17 elements, including mercury, in the tissues, food and abiotic environment of Arctic shorebirds

Exposure to contaminants is one hypothesis proposed to explain the global decline in shorebirds, and is also an increasing concern in the Arctic. We assessed potential contaminants (As, Be, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Sb, Se, Tl, V, and Zn) at a shorebird breeding site in Nunavut, Canada. We compared element levels in soil, invertebrates and shorebird blood to assess evidence for bioconcentration and biomagnification within the Arctic-based food chain. We tested whether elements in blood, feathers and eggs of six shorebird species (Pluvialis squatarola, Calidris alpina, C. fuscicollis, Phalaropus fulicarius, Charadrius semipalmatus, and Arenaria interpres) were related to fitness endpoints: adult body condition, blood-parasite load, egg size, eggshell thickness, nest duration, and hatching success. To facilitate comparison to other sites, we summarise the published data on toxic metals in shorebird blood and egg contents.Element concentrations and invertebrate composition differed strongly among habitats, and habitat use and element concentrations differed among shorebird species. Hg, Se, Cd, Cu, and Zn bioconcentrated from soil to invertebrates, and Hg, Se and Fe biomagnified from invertebrates to shorebird blood. As, Ni, Pb, Co and Mn showed significant biodilution from soil to invertebrates to shorebirds. Soil element levels were within Canadian guidelines, and invertebrate Hg levels were below dietary levels suggested for the protection of wildlife. However, maximum Hg in blood and eggs approached levels associated with toxicological effects and Hg-pollution in other bird species. Parental blood-Hg was negatively related to egg volume, although the relationship varied among species. No other elements approached established toxicological thresholds. In conclusion, whereas we found little evidence that exposure to elements at this site is leading to the declines of the species studied, Hg, as found elsewhere in the Canadian Arctic, is of potential concern for breeding bird populations.     

Short-term variability of dissolved trace element concentrations in the Marne and Seine rivers near Paris

The concentrations of dissolved trace elements (Li, B, Mn, Cu, As, Rb, Sr, Mo, Cd, Ba, Pb) in the Marne and Seine rivers in the Paris urban area were monitored over a 2-year period. The resulting data indicated moderate contamination of waters by the most toxic elements (Cu, As, Cd and Pb). The River Marne upstream and the River Seine downstream of the city of Paris displayed similar concentrations. However higher fluxes of trace elements were observed in the Seine than in the Marne due to their different discharges. Li, B, Rb, Sr and Ba concentrations were correlated with river discharge and concentrations were higher during high river flow. This was interpreted as a dilution by discharge from a major natural or anthropogenic source. Mn, Cu, Mo, Cd and Pb concentrations were not correlated with discharge. Dissolved Mn, Cu and Cd increased rapidly in summer, whereas the concentration of Mo decreased. These variations were attributed to redox processes. During summer when the dissolved oxygen concentrations decrease, Mn, Cu, Cd and Pb are released into solution whereas Mo is immobilised. Like metals, variations in arsenic contents were not linked with discharge. Its similarity with phosphate distribution suggests similar controls involving phytoplankton uptake and release from sediments through organic matter mineralization.     

Elemental contamination of Japanese women's hair from historical samples

Japanese women's hair, which had been cut in the past and preserved was examined for the presence of 12 elements (Na, K, Mg, Ca, Sr, Mn, Fe, Cu, Zn, Hg, Pb and P). Elevated levels of Fe, Mn, Cu, Pb and Hg (inorganic mercury) were conspicuous in the samples cut in the period 1880-1929 and used as hair pieces (kamoji). The effects of washing on element concentration depended on both the method of washing and the type of element. The least effective was washing with acetone and water, compared with two other methods involving anionic or non-ionic surface active agents. The most resistant elements to washing were Pb, Hg, Cu and Zn. From the intercorrelation of element content and factor analysis, by examining the diminution of contents by washing and by comparing the detected levels with the values measured on contemporary Japanese women's hair, the contribution of exogenous contamination to hair levels was found to be very strong for Fe, Mn, Cu, Hg (inorganic mercury), and Pb, moderate for Na and Zn, and negligible for Ca, Mg, Sr, K, Hg (organic mercury), and P.     

Trace element levels in whole blood of riparian villagers of the Brazilian Amazon

Monitoring the nutritional status of essential elements is of critical importance in human health. However, trace element concentrations in biological fluids are affected by environmental and physiological parameters, and therefore considerable variations can occur between specific population subgroups. Brazil is a large country with much food diversity. Moreover, dietary habits differ from north to south. As an example, the traditional populations of the Brazilian Amazon basin are heavily dependent on fish, fruits, vegetables and manioc for their daily sustenance. However, very few studies have examined to what extent these diets reflect adequate nutritional status for essential elements. Then, in the present study we have evaluated the levels of some trace elements (Cu, Co, Zn Sr, and Rb) in the whole blood of a riparian Brazilian Amazonian population and estimated the influence of age and gender on levels and inter-element interactions in the same population. For this, 253 subjects, aged 15 to 87, from 13 communities situated on the banks of the Tapajós, one of the major tributaries of the Amazon, were randomly selected. The values found for cobalt, copper and strontium in whole blood are in the same range as in other populations. On the other hand, the levels of rubidium and zinc may be considered higher. Moreover, gender was shown to influence Zn and Cu levels while age influenced the concentrations of Sr and Rb in men and Cu in women. Given the scarcity of studies examining nutritional status in traditional communities of the Amazon, our study is the first to provide relevant insight into trace element values in this region and inter-element interactions. This paper is also of particular importance for future studies looking at the possible protective effects of traditional Amazon riparian diets against mercury intake from fish consumption.     

Atmospheric heavy metal deposition in Finland during 1985-2000 using mosses as bioindicators

Heavy metal deposition and changes in the deposition patterns were investigated on the basis of surveys carried out in 1985, 1990, 1995 and 2000. The concentrations of 10 elements (Cd, Cr, Cu, Fe, Ni, Pb, Zn and V; and As and Hg since 1995) were determined on moss (Hylocomium splendens, Pleurozium schreberi) samples collected from the same permanent sample plots in each survey. The heavy metal concentrations, apart from those in southernmost Finland and close to a number of major emission sources, were relatively low. The mean concentrations of all the heavy metals decreased during the period covered by the surveys. The metals that showed the strongest decrease in concentration since 1985 were Pb (78%), V (70%) and Cd (67%). The concentrations of the other heavy metals decreased by 16-34%. The concentrations of Cr, Cu and Ni were clearly associated with local emission point sources and changes in emission levels. The concentrations of As and Hg, which were measured for the first time during the 1995 survey, decreased on the average by 26% and 10%, respectively.     

Distribution of some trace metals in Lochnagar, a Scottish mountain lake ecosystem and its catchment

Anthropogenic trace metals enter the entire ecosystem of Lochnagar solely through atmospheric deposition. Trace metals, including Hg, have been monitored in atmospheric deposition and lake water, and measured in catchment vegetation, aquatic plants and zooplankton, revealing contamination levels in the ecosystem. Furthermore, 17 sediment cores were taken from different areas of the lake. Hg, Pb, Cd, Zn and Cu were analysed in all the cores, which show that the sediments have been heavily contaminated by these trace metals since the 1860s. The distribution of trace metals in the lake sediments was found to be heterogeneous, with concentrations in the surface sediments varying significantly: 110-250 ng/g, 100-360 microg/g, 39-180 microg/g, 0.3-1.9 microg/g and 8-25 microg/g for Hg, Pb, Zn, Cd and Cu, respectively. Trends in the concentration profiles for different trace metals in the same core are different, as are the trends of the profiles for the same metal in different cores. Hence, a single sediment core cannot represent the pollution history of the whole lake. As the soils and sediments contain a high proportion of plant debris and the debris has a high affinity for Hg, resulting in Hg enrichment. Hg was measured in plant debris (> 63 microm) separated from catchment soils and lake sediments. Plant debris may play an important role in storing and transferring Hg in this ecosystem.     

Kidney and liver levels of some major, minor and trace elements in two Ontario communities

The contents of Ag, As, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Mo, Na, Ni, P, Pb, Se, Sr, Th, Ti and Zn in 143 autopsied liver and kidney specimens from two Ontario communities (Kingston and Ottawa) were determined using the techniques of inductively-coupled plasma--atomic emission spectrometry, and electrothermal atomization--atomic absorption spectrometry coupled with hydride evolution (As, Se), reduction--aeration (Hg), or solvent extraction (Pb). The majority of samples came from individuals older than 50 y. In general, the data for the various elements were independent of age or sex but showed some dependence on location for elements such as Cu, Fe, K, Mg, Mn, Na, P, Se and Zn. Despite these differences the elemental values of the liver and kidney samples from both the communities were within the normal range.