Toxic elements in arctic and sub-arctic brown bears: Blood concentrations of As, Cd, Hg and Pb in relation to diet, age, and human footprint.

Contamination with arsenic (As), cadmium (Cd), mercury (Hg) and lead (Pb) is a global concern impairing resilience of organisms and ecosystems. Proximity to emission sources increases exposure risk but remoteness does not alleviate it. These toxic elements are transported in atmospheric and oceanic pathways and accumulate in organisms. Mercury accumulates in higher trophic levels. Brown bears (Ursus arctos), which often live in remote areas, are long-lived omnivores, feeding on salmon (Oncorhynchus spp.) and berries (Vaccinium spp.), resources also consumed by humans. We measured blood concentrations of As, Cd, Hg and Pb in bears (n = 72) four years and older in Scandinavia and three national parks in Alaska, USA (Lake Clark, Katmai and Gates of the Arctic) using high-resolution, inductively-coupled plasma sector field mass spectrometry. Age and sex of the bears, as well as the typical population level diet was associated with blood element concentrations using generalized linear regression models. Alaskan bears consuming salmon had higher Hg blood concentrations compared to Scandinavian bears feeding on berries, ants (Formica spp.) and moose (Alces). Cadmium and Pb blood concentrations were higher in Scandinavian bears than in Alaskan bears. Bears using marine food sources, in addition to salmon in Katmai, had higher As blood concentrations than bears in Scandinavia. Blood concentrations of Cd and Pb, as well as for As in female bears increased with age. Arsenic in males and Hg concentrations decreased with age. We detected elevated levels of toxic elements in bears from landscapes that are among the most pristine on the planet. Sources are unknown but anthropogenic emissions are most likely involved. All study areas face upcoming change: Increasing tourism and mining in Alaska and more intensive forestry in Scandinavia, combined with global climate change in both regions. Baseline contaminant concentrations as presented here are important knowledge in our changing world.

Cu isotopes in marine black shales record the Great Oxidation Event.

The oxygenation of the atmosphere ∼2.45-2.32 billion years ago (Ga) is one of the most significant geological events to have affected Earth's redox history. Our understanding of the timing and processes surrounding this key transition is largely dependent on the development of redox-sensitive proxies, many of which remain unexplored. Here we report a shift from negative to positive copper isotopic compositions (δ(65)CuERM-AE633) in organic carbon-rich shales spanning the period 2.66-2.08 Ga. We suggest that, before 2.3 Ga, a muted oxidative supply of weathering-derived copper enriched in (65)Cu, along with the preferential removal of (65)Cu by iron oxides, left seawater and marine biomass depleted in (65)Cu but enriched in (63)Cu. As banded iron formation deposition waned and continentally sourced Cu became more important, biomass sampled a dissolved Cu reservoir that was progressively less fractionated relative to the continental pool. This evolution toward heavy δ(65)Cu values coincides with a shift to negative sedimentary δ(56)Fe values and increased marine sulfate after the Great Oxidation Event (GOE), and is traceable through Phanerozoic shales to modern marine settings, where marine dissolved and sedimentary δ(65)Cu values are universally positive. Our finding of an important shift in sedimentary Cu isotope compositions across the GOE provides new insights into the Precambrian marine cycling of this critical micronutrient, and demonstrates the proxy potential for sedimentary Cu isotope compositions in the study of biogeochemical cycles and oceanic redox balance in the past.

Sublethal Lead Exposure Alters Movement Behavior in Free-Ranging Golden Eagles.

Lead poisoning of animals due to ingestion of fragments from lead-based ammunition in carcasses and offal of shot wildlife is acknowledged globally and raises great concerns about potential behavioral effects leading to increased mortality risks. Lead levels in blood were correlated with progress of the moose hunting season. Based on analyses of tracking data, we found that even sublethal lead concentrations in blood (25 ppb, wet weight), can likely negatively affect movement behavior (flight height and movement rate) of free-ranging scavenging Golden Eagles (Aquila chrysaetos). Lead levels in liver of recovered post-mortem analyzed eagles suggested that sublethal exposure increases the risk of mortality in eagles. Such adverse effects on animals are probably common worldwide and across species, where game hunting with lead-based ammunition is widespread. Our study highlights lead exposure as a considerably more serious threat to wildlife conservation than previously realized and suggests implementation of bans of lead ammunition for hunting.

Multi-isotopic composition of brown crab (Cancer pagurus) and seafloor sediment from a mine tailing sea disposal impacted fjord ecosystem.

Sea disposal of mine tailings in fjord ecosystems is an important coastal management issue in Norway and occurs at the land-sea interface. Here we studied accumulation of heavy metals in brown crab (Cancer pagurus) and seafloor sediment from Jøssingfjord, Norway during 2018 to evaluate long-term, legacy pollution effects of coastal mine tailing sea disposal activities. Nickel and copper sediment pollution in the mine tailing sea disposal area was classified as moderate and severe, respectively, under Norwegian environmental quality standards, and highlights the persistent hazard and legacy impacts of heavy metals in these impacted fjord ecosystems. Mercury, zinc, and arsenic had stronger affinities to brown crab muscle likely due to the presence of thiols, and availability of metal binding sites. Our multi-isotopic composition data showed that lead isotopes were the most useful source apportionment tool for this fjord. Overall, our study highlights the importance and value of measuring several different heavy metals and multiple isotopic signatures in different crab organs and seafloor sediment to comprehensively evaluate fjord pollution and kinetic uptake dynamics. Brown crabs were suitable eco-indicators of benthic ecosystem heavy metal pollution in a fjord ecosystem still experiencing short- and long-term physical and chemical impacts from coastal mining sea disposal activities.

Isotopic analyses by ICP-MS in clinical samples.

This critical review focuses on inductively coupled plasma mass spectrometry (ICP-MS) based applications for isotope abundance ratio measurements in various clinical samples relevant to monitoring occupational or environmental exposure, human provenancing and reconstruction of migration pathways as well as metabolic research. It starts with a brief overview of recent advances in ICP-MS instrumentation, followed by selected examples that cover the fields of accurate analyte quantification using isotope dilution, tracer studies in nutrition and toxicology, and areas relying upon natural or man-made variations in isotope abundance ratios (Pb, Sr, actinides and stable heavy elements). Finally, some suggestions on future developments in the field are provided.

Multi-Element Assessment of Potentially Toxic and Essential Elements in New and Traditional Food Varieties in Sweden.

With the global movement toward the consumption of a more sustainable diet that includes a higher proportion of plant-based foods, it is important to determine how such a change could alter the intake of cadmium and other elements, both essential and toxic. In this study, we report on the levels of a wide range of elements in foodstuffs that are both traditional and "new" to the Swedish market. The data were obtained using analytical methods providing very low detection limits and include market basket data for different food groups to provide the general levels in foods consumed in Sweden and to facilitate comparisons among traditional and "new" food items. This dataset could be used to estimate changes in nutritional intake as well as exposure associated with a change in diet. The concentrations of known toxic and essential elements are provided for all the food matrices studied. Moreover, the concentrations of less routinely analyzed elements are available in some matrices. Depending on the food variety, the dataset includes the concentrations of inorganic arsenic and up to 74 elements (Ag, Al, As, Au, B, Ba, Be, Bi, Ca, Cd, Co, Cr, Cs, Cu, Fe, Ga, Ge, Hf, Hg, K, Li, Mg, Mn, Mo, Na, Nb, Ni, P, Pb, Rb, S, Sb, Sc, Se, Si, Sn, Sr, Ta, Te, Th, Ti, Tl, U, W, V, Y, Zn, Zr, rare Earth elements (REEs) (Ce, Dy, Er, Eu, Gd, Ho, La, Lu, Nd, Pr, Sm, Tb, Tm, and Yb), platinum group elements (PGEs) (Ir, Os, Pd, Pr, Pt, Re, Rh, Ru, and Pr), and halogens (Br, Cl, and I)). The main focus (and thus the most detailed information on variation within a given food group) is on foods that are currently the largest contributors to dietary cadmium exposure in Sweden, such as pasta, rice, potato products, and different sorts of bread. Additionally, elemental concentrations in selected food varieties regarded as relatively new or "novel" to the Swedish market are provided, including teff flour, chia seeds, algae products, and gluten-free products.

A comprehensive evaluation of sulfur isotopic analysis (δ34S and δ33S) using multi-collector ICP-MS with characterization of reference materials of geological and biological origin.

Sulfur isotope ratios are often used as biogeochemical tracers to gain understanding of abiotic and biological processes involved in the sulfur cycle in both modern and ancient environments. There is however a lack of matrix-matched well-characterized isotopic reference materials that are essential for controlling the accuracy and precision. This study therefore focused on expanding and complementing the currently available sulfur isotope ratio data by providing the bulk sulfur isotopic composition, as determined using multi-collector inductively coupled plasma-mass spectrometry (MC-ICP-MS), for a comprehensive set of commercially and/or readily available biological and geological reference materials. A total 7 isotopic reference materials and 41 elemental reference materials were studied. These reference materials include standards of terrestrial and marine animal origin, terrestrial plant origin, human origin, and geological origin. Different sample preparation protocols, including digestion and subsequent chromatographic isolation of S, were evaluated and the optimum approach selected for each matrix type. For achieving enhanced robustness, the sample preparation and sulfur isotope ratio measurements were done at two different laboratories for selected reference materials, while at one of the laboratories the measurements were additionally performed using two different MC-ICP-MS instruments. Determined δ34SVCDT and δ33SVCDT values compared well between the different laboratories, as well as between the different generation MC-ICP-MS instruments, and for standards that were previously characterized, our data are similar to literature values. The δ34SVCDT ranges determined for the different categories of the reference materials - terrestrial animal origin: +2 to +9‰, marine animal origin: +15 to +20‰, human origin: +6 to +10‰, terrestrial plant origin: -20 to +7‰, and geological origin: -12 to +21‰ - fit the expected values based on previous studies of similar types of matrices well. No significant mass-independent fractionation is observed when considering the expanded uncertainties for Δ33SV-CDT.

Venetian Protected Designation of origin wines traceability: Multi-elemental, isotopes and chemometric analysis.

The traceability and authentication of PDOs wines are important issues for safeguarding their production and distribution systems. This paper evaluated seven Venetian PDO wines, i.e., Amarone, Bardolino, Custoza, Pinot Grigio, Recioto, Soave and Valpolicella. For this purpose, 219 wine samples from the Veneto region were characterised by determining 63 elements and six isotope ratios by HR-ICP-MS and MC-ICP-MS. Chemometric tools highlighted As, Ca, Cs, δ11B and 87Sr/86Sr as the most informative variables to differentiate the PDOs. Seven classification methods, such as Linear Discriminant Analysis, Quadratic Discriminant Analysis, k-Nearest Neighbours, Naïve Bayes, Random Forest, Artificial Neural Networking, and Support Vector Machine were tested and perform a correct classification for Amarone, Bardolino, Pinot Grigio and Recioto PDOs. This paper successfully proposes for the first time advanced traceability tools of seven Venetian PDO by the use of an integrated approach of multi-elemental and isotopes followed by chemometrics analysis.

Managing health risks in urban agriculture: The effect of vegetable washing for reducing exposure to metal contaminants.

A common, yet poorly evaluated, advice to remove contaminants from urban vegetables is to wash the produce before consumption. This study is based on 63 samples of chard, kale, lettuce and parsley that have grown near a heavily trafficked road in the third largest city in Sweden, with one portion of each sample being analysed without first being washed, and the other portion being subjected to common household washing. Concentrations of 71 elements were analysed by ICP-SFMS after a sample digestion that dissolves both the plant tissues and all potentially adhering particles. The results show that the washing effect, or the fraction removed upon washing, varies significantly between elements: from approximately 0 % for K to 68 % for the ∑REEs. Considering traditional metal contaminants, the efficiency decreased from Pb (on average 56 % lost) to Co (56 %) > Cr (55 %) > As (45 %) > Sb (35 %) > Ni (33 %) > Cu (13 %) > Zn (7 %) > Cd (7 %), and Ba (5 %). A clear negative correlation between the washing effect and the different elements' bioconcentration factors shows that the elements' accessibility for plant uptake is a key controlling factor for the degree to which they are removed upon washing. Based on the average washing efficiencies seen in this study, the average daily intake of Pb would increase by 130 % if vegetables are not washed prior to consumption. For the other contaminant metals this increase corresponds to 126 % (Co), 121 % (Cr), 82 % (As), 55 % (Sb), 50 % (Ni), 16 % (Cu), 8 % (Zn), 7 % (Cd) and 5 % (Ba). The advice to wash vegetables is therefore, for many elements, highly motivated for reducing exposure and health risks. For elements which are only slightly reduced when the vegetables are washed, however, advising should rather focus on reducing levels of contamination in the soil itself.

Lead exposure in brown bears is linked to environmental levels and the distribution of moose kills.

Lead (Pb) is heterogeneously distributed in the environment and multiple sources like Pb ammunition and fossil fuel combustion can increase the risk of exposure in wildlife. Brown bears (Ursus arctos) in Sweden have higher blood Pb levels compared to bears from other populations, but the sources and routes of exposure are unknown. The objective of this study was to quantify the contribution of two potential sources of Pb exposure in female brown bears (n = 34 individuals; n = 61 samples). We used multiple linear regressions to determine the contribution of both environmental Pb levels estimated from plant roots and moose (Alces alces) kills to blood Pb concentrations in female brown bears. We found positive relationships between blood Pb concentrations in bears and both the distribution of moose kills by hunters and environmental Pb levels around capture locations. Our results suggest that the consumption of slaughter remains discarded by moose hunters is a likely significant pathway of Pb exposure and this exposure is additive to environmental Pb exposure in female brown bears in Sweden. We suggest that spatially explicit models, incorporating habitat selection analyses of harvest data, may prove useful in predicting Pb exposure in scavengers.

137Cs and isotopic ratios of Pu and U in lichens and mosses from Russian Arctic areas.

Knowledge of past anthropogenic sources of radionuclide contamination in Russian Arctic areas is important to assess the radioecological situation of these less-studied regions. Therefore, we investigated the sources of radionuclide contamination in Russian Arctic in the 1990s. Lichen and moss samples were collected from 1993 to 1996 in Kola Peninsula, Franz Josef Land, and few other locations. The activity concentration of 137Cs was determined from the archived samples by gamma spectrometry in 2020. After radiochemical separation of Pu and U isotopes from the lichens and mosses, mass ratios 240Pu/239Pu, 234U/238U, 235U/238U, and 236U/238U were determined by mass spectrometry. 137Cs activity concentrations at the sampling date were found to vary from 3.1 ± 1.4 (Inari, Finnish-Russian border) to 303 ± 7 (Kola Peninsula) Bq/kg. The ranges of isotopic ratios were 0.0592 ± 0.0007 to 0.253 ± 0.082 for 240Pu/239Pu, (4.89 ± 3.91) × 10-5 to (6.86 ± 0.04) × 10-5 for 234U/238U, 0.0072104(21) to 0.007376(41) for 235U/238U, and from below 1 × 10-7 to (2.65 ± 0.19) × 10-6 for 236U/238U, respectively. Based on the measured isotopic ratios and characteristic isotopic ratios of known contamination sources, the main Pu and U sources in the sampled lichens and mosses are global fallout, the Chernobyl accident, and possibly local nuclear activities. These results contribute to further understanding of past nuclear events and resulting nuclear contamination in Russian Arctic terrestrial areas.

Longitudinal isotope ratio variations in human hair and nails.

Due to the straightforward and non-invasive sampling, ease of transport and long-term storage and access to time-resolved information, determination of element concentrations and isotope ratios in hair and nails finds increasing use. Multi-isotopic information preserved in keratinous tissues allows one to reveal dietary, physiological and environmental influences, but progress in this area is still limited by complicated and time-consuming analytical procedures and challenges in accuracy assessment. In this study, longitudinal distributions of δ34S, 87Sr/86Sr, 207,208Pb/206Pb, δ66Zn, δ56Fe, δ65Cu, δ26Mg, and δ114Cd were obtained for hair and nails collected from nine subjects with different age, biological sex, diet and/or place of residence. For S and Zn, the distribution along hair strands revealed a trend towards a heavier isotopic signature from the proximal to the distal end, with a maximum difference within the hair of a single subject of 1.2‰ (Δ34S) and 0.4‰ (Δ66Zn). For Fe, Cu, Mg and Cd, a shift towards either a lighter (Cu) or heavier (Fe, Mg and Cd) isotopic composition is accompanied by increasing concentration towards the distal hair end, indicating possible isotope fractionation during deposition or external contamination with a different isotopic composition. Pb and Sr isotope ratios are relatively stable throughout the hair strands despite notable concentration increases towards the distal end, likely reflecting external contamination. The isotopic composition of Sr points to tap water as a probable main source, explaining the relative stability of the ratio for individuals from the same geographical location. For Pb, isotopic compositions suggest tap water and/or indoor dust as possible sources. Similar δ34S, 87Sr/86Sr, 207,208Pb/206Pb, δ66Zn, δ56Fe, and δ65Cu observed for hair, fingernails and toenails sampled from the same individual suggest that keratinous tissues are conservative receivers of internal and external inputs and can be used complementary. Seasonal variation in δ34S, 207,208Pb/206Pb, and δ65Cu was observed for fingernails.

Blood, urine, and sweat (BUS) study: monitoring and elimination of bioaccumulated toxic elements.

There is limited understanding of the toxicokinetics of bioaccumulated toxic elements and their methods of excretion from the human body. This study was designed to assess the concentration of various toxic elements in three body fluids: blood, urine and sweat. Blood, urine, and sweat were collected from 20 individuals (10 healthy participants and 10 participants with various health problems) and analyzed for approximately 120 various compounds, including toxic elements. Toxic elements were found to differing degrees in each of blood, urine, and sweat. Serum levels for most metals and metalloids were comparable with those found in other studies in the scientific literature. Many toxic elements appeared to be preferentially excreted through sweat. Presumably stored in tissues, some toxic elements readily identified in the perspiration of some participants were not found in their serum. Induced sweating appears to be a potential method for elimination of many toxic elements from the human body. Biomonitoring for toxic elements through blood and/or urine testing may underestimate the total body burden of such toxicants. Sweat analysis should be considered as an additional method for monitoring bioaccumulation of toxic elements in humans.

Early diagenesis of anthropogenic uranium in lakes receiving deep groundwater from the Kiruna mine, northern Sweden.

The uranium (U) concentrations and isotopic composition of waters and sediment cores were used to investigate the transport and accumulation of U in a water system (tailings pond, two lakes, and the Kalix River) receiving mine waters from the Kiruna mine. Concentrations of dissolved U decrease two orders of magnitude between the inflow of mine waters and in the Kalix River, while the concentration of the element bound to particulate matter increases, most likely due to sorption on iron­manganese hydroxides and organic matter. The vertical distribution of U in the water column differs between two polluted lakes with a potential indication of dissolved U supply from sediment's pore waters at anoxic conditions. Since the beginning of exposure in the 1950s, U concentrations in lake sediments have increased >20-fold, reaching concentrations above 50 µg g-1. The distribution of anthropogenic U between the lakes does not follow the distribution of other mine water contaminants, with a higher relative proportion of U accumulating in the sediments of the second lake. Concentrations of redox-sensitive elements in the sediment core as well as Fe isotopic composition were used to re-construct past redox-conditions potentially controlling early diagenesis of U in surface sediments. Two analytical techniques (ICP-SFMS and MC-ICP-MS) were used for the determination of U isotopic composition, providing an extra dimension in the understanding of processes in the system. The (234 U)/(238 U) activity ratio (AR) is rather uniform in the tailings pond but varies considerably in water and lake sediments providing a potential tracer for U transport from the Kiruna mine through the water system, and U immobilization in sediments. The U mass balance in the Rakkurijoki system as well as the amount of anthropogenic U accumulated in lake sediments were evaluated, indicating the immobilization in the two lakes of 170 kg and 285 kg U, respectively.

Low-level environmental metal pollution is associated with altered gut microbiota of a wild rodent, the bank vole (Myodes glareolus).

Mining and related industries are a major source of metal pollution. In contrast to the well-studied effects of exposure to metals on animal physiology and health, the impacts of environmental metal pollution on the gut microbiota of wild animals are virtually unknown. As the gut microbiota is a key component of host health, it is important to understand whether metal pollution can alter wild animal gut microbiota composition. Using a combination of 16S rRNA amplicon sequencing and quantification of metal levels in kidneys, we assessed whether multi-metal exposure (the sum of normalized levels of fifteen metals) was associated with changes in gut microbiota of wild bank voles (Myodes glareolus) from two locations in Finland. Exposure to increased metal load was associated with higher gut microbiota species diversity (α-diversity) and altered community composition (ß-diversity), but not dispersion. Multi-metal exposure and increased levels of several metals (Cd, Hg, Pb and Se) were associated with differences in the abundance of microbial taxa, especially those within the families Clostridiales vadinBB60 group, Desulfovibrionaceae, Lachnospiraceae, Muribaculaceae and Ruminococcaceae. Our data indicate that even low-level metal pollution can affect the diversity of microbiota and be associated with deterministic differences in composition of host gut microbiota in wild animal populations. These findings highlight the need to study a broader range of metals and their cocktails that are more representative of the types of environmental exposure experienced by wild animals.

High concentrations of lead (Pb) in blood and milk of free-ranging brown bears (Ursus arctos) in Scandinavia.

Exposure to lead (Pb) is a global health problem for both humans and wildlife. Despite a dramatic decline in human Pb exposure following restrictions of leaded gasoline and industry and thereby an overall reduction of Pb entering the environment, Pb exposure continues to be a problem for wildlife species. Literature on scavenging terrestrial mammals, including interactions between Pb exposure and life history, is however limited. We quantified Pb concentration in 153 blood samples from 110 free-ranging Scandinavian brown bears (Ursus arctos), 1-25 years old, using inductively coupled plasma sector field mass spectrometry. We used generalized linear models to test effects of age, body mass, reproduction status and spatial distribution on the blood Pb concentrations of 56 female bears. We sampled 28 females together with 56 dependent cubs and paired their blood Pb concentrations. From 20 lactating females, we measured the Pb concentration in milk. The mean blood Pb concentration was 96.6 µg/L (range: 38.7-220.5 µg/L). Both the mean and range are well above established threshold concentrations for developmental neurotoxicity (12 µg/L), increased systolic blood pressure (36 µg/L) and prevalence of kidney disease in humans (15 µg/L). Lactating females had higher Pb blood concentrations compared to younger, non-lactating females. Blood Pb concentrations of dependent cubs were correlated with their mother's blood Pb concentration, which in turn was correlated with the Pb concentration in the milk. Life-long Pb exposure in Scandinavian brown bears may have adverse effects both on individual and population levels. The high blood Pb concentrations found in brown bears contrast the general reduction in environmental Pb contamination over the past decades in Scandinavia and more research is needed to identify the sources and pathways of Pb exposure in the brown bears.

Sources of contamination and remedial strategies in the multi-elemental trace analysis laboratory.

In theory, state of the art inductively coupled plasma mass spectrometry (ICP-MS) instrumentation has the prerequisite sensitivity to carry out multi-elemental trace analyses at sub-ng L-1 to sub-pg L-1 levels in solution. In practice, constraints mainly imposed by various sources of contamination in the laboratory and the instrument itself, and the need to dilute sample solutions prior to analysis ultimately limit detection capabilities. Here we review these sources of contamination and, wherever possible, propose remedial strategies that we have found efficacious for ameliorating their impact on the results of multi-elemental trace analyses by ICP-MS. We conclude by providing a list of key points to consider when developing methods and preparing the laboratory to routinely meet the demands of multi-elemental analyses at trace analytical levels by ICP-MS.

Spatio-temporal variation of metals and organic contaminants in bank voles (Myodes glareolus).

Environmental contamination with metals and organic compounds is of increasing concern for ecosystem and human health. Still, our knowledge about spatial distribution, temporal changes and ecotoxicological fate of metals and organic contaminants in wildlife is limited. We studied concentrations of 69 elements and 50 organic compounds in 300 bank voles (Myodes glareolus), Europe's most common mammal, sampled in spring and autumn 2017-2018 in five monitoring areas, representing three biogeographic regions. In addition, we compared measured concentrations with previous results from bank voles sampled within the same areas in 1995-1997 and 2001. In general, our results show regional differences, but no consistent patterns among contaminants and study areas. The exception was for the lowest concentrations of organic contaminants (e.g. perfluorooctane sulfonate, PFOS), which were generally found in the northern Swedish mountain area. Concentrations of metals and organic contaminants in adults varied seasonally with most organic contaminants being higher in spring; likely induced by diet shifts but potentially also related to age differences. In addition, metal concentrations varied between organs (liver vs. kidney), age classes (juveniles vs. adults; generally higher in adults) as well as between males and females. Concentrations of chromium and nickel in kidney and liver in the northernmost mountain area were lower in 2017-2018 than in 1995-1997 and in three of four areas, lead concentrations were lower in 2017-2018 than in 2001. Current metal concentrations (except mercury) are not expected to negatively affect the voles. Concentrations of hexachlorobenzene displayed highest concentrations in 2001 in the mountains, while it was close to detection limit in 2017-2018. Likewise, PFOS concentrations decreased in the mountains and in south-central lowland forests between 2001 and 2017-2018. Our results suggest that season, age class and sex need to be considered when designing and interpreting results from monitoring programs targeting inorganic and organic contaminants in wildlife.

Determination of total chlorine and bromine in solid wastes by sintering and inductively coupled plasma-sector field mass spectrometry.

A sample preparation method based on sintering, followed by analysis by inductively coupled plasma-sector field mass spectrometry (ICP-SFMS) for the simultaneous determination of chloride and bromide in diverse and mixed solid wastes, has been evaluated. Samples and reference materials of known composition were mixed with a sintering agent containing Na(2)CO(3) and ZnO and placed in an oven at 560 degrees C for 1h. After cooling, the residues were leached with water prior to a cation-exchange assisted clean-up. Alternatively, a simple microwave-assisted digestion using only nitric acid was applied for comparison. Thereafter the samples were prepared for quantitative analysis by ICP-SFMS. The sintering method was evaluated by analysis of certified reference materials (CRMs) and by comparison with US EPA Method 5050 and ion chromatography with good agreement. Median RSDs for the sintering method were determined to 10% for both chlorine and bromine, and median recovery to 96% and 97%, respectively. Limits of detection (LODs) were 200mg/kg for chlorine and 20mg/kg for bromine. It was concluded that the sintering method is suitable for chlorine and bromine determination in several matrices like sewage sludge, plastics, and edible waste, as well as for waste mixtures. The sintering method was also applied for determination of other elements present in anionic forms, such as sulfur, arsenic, selenium and iodine.

Assessment of the LeadCare® Plus for Use on Scandinavian Brown Bears (Ursus arctos).

Lead (Pb) exposure is associated with adverse health effects in both humans and wildlife. Blood lead levels (BLL) of sentinel wildlife species can be used to monitor environmental lead exposure and ecosystem health. BLL analyzers, such as the LeadCare®, are validated for use in humans, assessed for use in some avian species and cattle, and are increasingly being used on wildlife to monitor lead exposure. The LeadCare® analyzers use a technique called anodic stripping voltammetry (ASV). Species-specific conversion equations have been proposed to approximate the levels found with gold standard measuring methods such as inductively coupled plasma mass spectrometry (ICP-MS) because the ASV method has been shown to underestimate BLL in some species. In this study we assessed the LeadCare® Plus (LCP) for use on Scandinavian brown bears (Ursus arctos). LCP measurements were correlated with ICP-MS with a Bland-Altman analyzed bias of 16.3-22.5%, showing a consistent overestimation of BLL analyzed with LCP. Based on this analysis we provide conversion equations for calculating ICP-MS BLL based on the LCP results in Scandinavian brown bears. Our study shows that the LeadCare® Plus can be used for monitoring of lead exposure by approximating gold standard levels using conversion equations. This enables comparison with other gold standard measured BLL within the observed range of this study (38.20-174.00 µg/L). Our study also found that Scandinavian brown bears are highly exposed to environmental lead.