Accumulation Of Trace Elements Research Articles

Cadmium accumulation, translocation factor, and health risk potential in a wastewater-irrigated soil-wheat (Triticum aestivum L.) system

The accumulation of trace elements in wastewater-irrigated soils may introduce them to the food chain and therefore can threaten human health. The present study investigated the accumulation, translocation factor, and health risk potential of cadmium (Cd) in a soil-wheat system irrigated with treated wastewater compared with a reference soil (irrigated with fresh water). All treated wastewater-irrigated soils showed significantly higher levels of electrical conductivity (EC) than that of reference soil by 75–143%. Irrigation with treated wastewater increased both available and total Cd content in soil by 2–4 times. In all irrigated sites, Cd content was about twice as great as the maximum acceptable rate. Bioconcentration factor (BCF) and translocation factor (TF) indicated that Cd was mainly accumulated in the roots (BCF = 2.2–3.1), while little mobilization from roots to stems and grains was noted (TFshoot/root = 0.07–0.21; TFgrain/root = 0.18–0.24). The average hazard quotient (HQ) for different age groups of the population varied in the range of 0.1–1.0, implying low non-carcinogenic health risk of Cd to local wheat-consuming residents. The risk of Cd to cause carcinogenic health risk (CR) was in the range of 1 × 10-5 to 1 × 10-4, indicating low to moderate potential risk. CR for different age groups was in the order: individuals above 18 years old > individuals 7–18 years old > individuals 0–6 years old. For reducing potential health risks to local people, it is imperative to continuously monitor heavy metal levels in the wheat-soil system and urgently adopt more efficient managerial strategies to reduce Cd contamination.

Biomonitoring environmental status in semi-enclosed coastal ecosystems using Zostera noltei meadows

Semi enclosed waters, such as estuaries and lagoons, are vulnerable ecosystems that are experiencing persistent trace element (TE) contamination. Seagrasses have been reported worldwide as valuable bioindicator species for coastal contamination monitoring purpose. This is, to our knowledge, the first time the TE contamination of semi-enclosed ecosystems has been monitored along the full latitudinal gradient of the Moroccan Atlantic coast. In these ecosystems, the dominant seagrass species is Zostera noltei. 23 TEs (Fe, Al, Cr, Mn, Co, Ni, V, Cu, Zn, Sr, Li, As, Ag, Cd, Sn, Sb, Mo, Ba, Ti, Pb, U, Bi and Hg) and four major elements (Na, Mg, K, Ca) were measured in sediments and seagrass leaf samples were collected upstream and downstream of five semi-enclosed areas. They contrasted in both climatic conditions and levels of environmental contamination. The Trace Element Pollution Index (TEPI) and the Trace Element Spatial Variation Index (TESVI) were calculated from chemical element concentrations in the samples. Of the five semi-enclosed areas, Sidi Moussa lagoon’s sediments were the most contaminated (TEPI = 1.18). The TESVI differed highly between chemical elements among the five water bodies for sediments and seagrass leaves, the highest spatial variability being for Ag (TESVI = 72.01 and 21.05 respectively). For Z. noltei leaves, a latitudinal gradient of TE accumulation was recorded. A high bioconcentration factor (BCF > 1) for Cd, Mo, Sb, Ag, Zn and U indicated that the sediments were efficiently uptaken by the seagrass. Significant correlations (p < 0.05) between levels of Cd, Ag, Fe, Al, Ba, Hg, Mn and Zn in sediments and in Z. noltei leaves indicated similar contamination occurrences in both environmental matrices and their bioavailability for seagrasses. Overall, leaf TE bioconcentration among and within the study sites resulted from differences in element bioavailability and environmental conditions (climatic context, hydrological conditions and human impact). Ultimately, Z. noltei is a useful bioindicator of Cd, Mo, Sb, Ag, Zn, U, Al, Fe, Mn, Ba and Hg contamination in sediments.

Detection of trace elements in freshwater macrobenthic invertebrates of different functional feeding guilds: A case study in Northeast Italy

Trace elements are common contaminants in aquatic ecosystems; their detection in biota yields information on their availability in the environment and provides an indirect indication of freshwater ecological status. We analyzed samples of freshwater macrobenthic invertebrates from six watercourses in Friuli Venezia-Giulia (Northeast Italy) to verify whether trace elements accumulation is related to their ecological status sensu Water Framework Directive (WFD), and to determine tropic level influences on the accumulation of 18 trace elements in macrobenthic communities. Observed concentrations could be in line with results of ecological status assessment defined by the WFD, in fact two sites classified as “Moderate” had the highest trace elements content. The genus Calopteryx (Odonata, predator) was positively correlated with Be, Cr, Fe, Mn, Mo, Ni, Sn, and V (ρS range 0.777–0.844). Positive correlations were also determined for the genus Rhyacophila (Trichoptera, predator) with Cu (ρS=0.757), suggesting bioaccumulation in macroinvertebrate tissue. Ephemeroptera of the genus Caenis (collector-gatherers) were positively correlated with Be, Fe, Mn, Pb, Sb, and V (ρS range 0.757–0.802), indicating that ingestion of sediment is the most effective uptake of these metals.Results of this study, albeit preliminary, showed that trace elements detection in aquatic macrobenthic invertebrates is a useful analysis for obtaining information about the status of freshwater course. Our study provides evidence for a greater accumulation of trace elements in predators and collector-gatherers, suggesting that the tropic level of macrobenthic communities influence the accumulation of trace elements.

Accumulation of trace elements in feathers of the Kentish plover Charadrius alexandrinus

A non-invasive study of trace element accumulation in tail feathers of the Kentish plover (Charadrius alexandrinus) was performed along the coastline of the northern littoral strip of the Venice Lagoon, with the aim to verify whether contamination may be a factor affecting conservation status of Kentish plover populations.Body burdens in feathers of 11 trace elements including toxic metals/metalloids and essential elements (As, Cd, Co, Cr, Cu, Hg, Ni, Pb, Se, V, Zn) were quantified by ICP-MS, then concentrations were normalized to feather's age calculated using ptilochronology in order to obtain daily deposition rates.Mercury emerged as a major threat to the conservation of the species, since average feather concentration was clearly above the adverse-effect threshold associated with impairment in the reproductive success in a number of bird species. Also Cd and Se occurred at levels that may impact on the conservation status of the studied species at local scale, even if to a lesser extent than Hg.Gender-related differences in trace element accumulation emerged only for As, although for this element the risks associated to environmental exposure seem to be negligible.

Levels of heavy metals in the straightfin barb Enteromius paludinosus (Peters 1852) from River Malewa, Naivasha, Kenya.

There have been several studies on heavy metals in Lake Naivasha. However, none of them has reported the levels of mercury (Hg), arsenic (As), and chromium (Cr). Moreover, there are no studies on the heavy metals' concentrations in the straightfin barb (Enteromius paludinosus, Peters 1852), a fish species that hosts a parasite (Ligula intestinalis), the latter having been reported to have a high ability to absorb heavy metals from its host. This paper therefore addresses the accumulation of heavy metals, namely arsenic (As), chromium (Cr), lead (Pb), and mercury (Hg) in the tissues of straightfin barb, Enteromius paludinosus (Peters 1852) from the mouth of River Malewa in Lake Naivasha, Kenya. A total of 1307 fish were collected during the month of November 2017. Water samples, sediment samples, 25 fish muscle tissues, and its endoparasite, the cestode Ligula intestinalis, were isolated, and heavy metal concentrations were determined using the thermal-electron atomic absorption spectrophotometer at the Lake Nakuru Water Quality Testing Laboratory. The concentrations of heavy metals in the sediment were below the lowest effect level in sediment, threshold effect concentration in sediment, severe effect concentration in sediment, and the shale values of sedimentary rocks thus showing no sign of pollution. In the muscle tissues of the fish, As, Cr, Pb, and Hg showed high levels with mean concentrations of 5.0696, 22.0854, 45.2108, and 1.5458mg/kg ww, respectively. Bioconcentration factors further supported the observation that trace element accumulation was higher in fish compared with sediment and water. The target hazard quotients of As, Cr, Pb, and Hg obtained for both the female and male were > 1 indicating a possible health risk associated with the consumption of E. paludinosus. The bioaccumulation factors (BAFs) for L. intestinalis were 2.4093, 2.1873, 5.8601, and 5.1395 for As, Cr, Pb, and Hg, respectively, indicating the potential of the cestode in the accumulation of heavy metals from the host; hence, it can be used as an accumulation bioindicator.

Trace elements sorption by bentonite in the presence of bacteria

Sorption of lead and copper by calcium bentonite, living and destroyed cells of gram-positive bacteria Bacillus subtilis, as well as in systems including the clay mineral and one of the biotic components in the concentration range of the elements from 25 to 250 μM was studied. The effect of acidity on the biosorption of trace elements was shown. The maximum biosorption of lead and copper was observed at pH 6 and reached 0.72 and 0.52 mM/g of dry matter, respectively. At pH 6 the maximum biosorption by the destroyed cells was also observed — 0.81 mM/g of lead and 0.71 mM/g of copper. Accumulation of trace elements by living and destroyed cells significantly exceeded their sorption by calcium bentonite. In the ternary systems, including bentonite and bacterial cells or bentonite and cell debris, there was an increase in the sorption of lead and copper compared to bentonite alone. At the same time, the sorption of trace elements by a mixture of bentonite and cell fragments was lower than the additively calculated sorption by the individual components for both lead and copper at all concentrations studied. A similar pattern was observed for the system of living cells and bentonite for copper and living cells and bentonite for lead at low metal concentrations.

Bryophytes as a bioindicator for atmospheric deposition in different coastal habitats (a case study in the Russian sector of the Curonian Spit, South-Eastern Baltic)

ABSTRACTThe paper describes the characteristics of accumulation of trace elements (iron (Fe), manganese (Mn), nickel, zinc (Zn), strontium (Sr), rubidium (Rb), bromine (Br) and calcium (Ca)) in moss of the natural systems of the Curonian Spit. These coastal marine ecosystems are highly susceptible to transformation by both natural and anthropogenic factors affecting the element concentration in bryophytes. The method employed to determine elemental composition of moss is X-ray fluorescence spectrometry. To explain the variations in the experimental data, the primary results were processed using descriptive statistics, correlation analysis and principal component analysis. The contamination factor was calculated. The correlation and principal component analysis revealed three factors. This may be owing to the effects of wind transport, atmospheric deposition, marine aerosol and leaching from plant residues.

Spatial and interspecies differences in concentrations of eight trace elements in wild freshwater fishes at different trophic levels from middle and eastern China

There have been numerous studies on concentrations of trace elements in aquatic ecosystems, but few have been conducted at a large spatial scale. This study collected 410 samples of five wild freshwater fishes at different trophic levels from middle and eastern China. Concentrations of eight trace elements, chromium (Cr), iron (Fe), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), lead (Pb) and cadmium (Cd) and stable isotope ratios (δ13C and δ15N) were determined in dorsal muscle of fishes. Spatially, concentrations of trace elements were least in fishes from the Hai River Basin, while those in fishes from the Taihu Lake Basin were greatest. The carnivorous topmouth culter and omnivorous common carp and crucian carp accumulated greater amounts of trace elements than did the planktivorous silver carp and bighead carp. Trophic biomagnification was for Cu, Fe and Zn, but not for Cr, Ni, As, Pb and Cd. Concentrations of As in 15 muscle samples (3.7%) from Taihu Lake Basin exceeded the guidelines (1.0 mg/kg, wet mass) provided by FAO/WHO (2014), while the total target hazard quotient (TTHQ) values were <1.0, indicating no obvious non-carcinogenic risks to humans that consume those fishes. However, people who consume larger amounts of fish products, or people who are vulnerable, such as pregnant women, children and people with poor health, might be at greater risk. Also, exposure to trace metals through other routes cannot be ignored. Accumulations of trace elements in Chinese freshwater fishes were affected by both geographical conditions and human activities.

Spatial distribution of soil trace element concentrations along an urban-rural transition zone in the black soil region of northeastern China

Urbanization is an important process that changes land use pattern and the sustainability of agroecosystems in the urban-rural transition zone. Through intensified anthropogenic activity, urbanization magnifies trace element (TE) inputs into soils and alters the balance of soil element fluxes. This study aims to investigate the effects of urbanization on the spatial dynamics of soil HMs in peri-urban zones and the distinct behaviors of TEs in response to urban sprawl. An area (15 km × 16 km) in the Chinese northeastern black soil region was selected to represent a typical urban-rural transition feature that received heavy impact by urbanization in last decade. Two hundred topsoil samples were taken from locations dominated by Phaeozem soils and analyzed for total Zn, Cu, As, Pb, Cd, Cr, Ni, and Hg. Principal component analysis (PCA) was used to distinguish the probable sources of TE inputs into the soils. The overall TE pollution of soils was evaluated by the Nemerow comprehensive pollution index. Inverse distance weighting algorithm combined with autocorrelation analysis was used to analyze the spatial patterns of soil TE distribution. The mean concentrations of the studied TEs, with the exception of Hg and As, were higher than their background values, and their concentrations were always higher in the part closer to the urbanized area. Soil pollution assessment shows that the overall pollution status was moderate, but for Cd and Cu, numerous hotspots were identified due to the overuse of agrochemicals. PCA showed that Cu, Zn, Pb, and Cd as the first component were due to urbanization and agronomic practices, whereas As, Ni, and Cr as a second group were primarily of lithogenic origin, partly due to urbanization, and Hg was related to the atmospheric deposition of industrial waste gas. Increasing urban sprawl in the study area resulted in higher TE concentrations in the southern part of the region than the northern part, confirming the positive effect of urbanization on excessive soil TE accumulation. Although the pollution status was not yet serious, with the current rate of urban growth, arable soils in the peri-urban area will continuously be contaminated and control measures must be taken to prevent the cumulative impact on human health.

Urban Allotment Gardens for the Biomonitoring of Atmospheric Trace Element Pollution.

This study evaluates the results of the characterization of air pollution in urban green areas using edible plants. To this purpose, we examined the effect of location (i.e., three different levels of pollution), substrate (peat moss and vermiculite), and plant species (oilseed rape [ L.] and kale [ L.]) on the accumulation of trace elements on leaves. A total of 36 samples of unwashed leaves were digested with HNO-HO and analyzed for 27 elements by inductively coupled plasma mass spectrometry. Considering the location, plants exposed next to the road showed higher contents of traffic-related elements, and additionally, outdoors samples were enriched in marine aerosol ions. Cadmium and Pb concentrations did not exceed the European legal maximum levels for vegetables, so their consumption would be safe for human health. Results support the hypothesis that edible plants such as kale and rapeseed could be used as bioindicators of atmospheric pollution.

Assessment of trace elements pollution in the sea ports of New South Wales (NSW), Australia using oysters as bioindicators

In this study Sydney rock oysters (S. glomerata) from six major sea ports of NSW, Australia were used as bioindicators to assess the distribution and levels of trace element accumulation in the ports. Substantial enrichment of Cu, Pb and Zn in the oysters of the sea ports were detected when compared to their background samples and the US Environmental Protection Agency (USEPA) provisional tolerable intake standard. Enrichment of As, Al, Fe, Mn, Br, Sr were also found in the oysters at the port areas. The bioconcentration ratios of the trace elements illustrated significant Fe, Cu, Zn, As, Mn, Al, Pb and Cr accumulation in S. glomerate. The biota sediment accumulation factor suggested Cu, Mn and Zn accumulation at two of the ports (Port Yamba and Botany), indicating availability of these metals in the oysters as strong metal accumulators. In addition, integrated metal contamination illustrated notable Fe, Zn, Cu and Al contamination at port environment, whereas cluster analysis portrayed interconnection between the contaminants and the study sites.

Trace Element Uptake by Herbaceous Plants from the Soils at a Multiple Trace Element-Contaminated Site.

The uptake of trace elements by wild herbaceous plants in a multiple trace element-contaminated site was investigated. The bioaccumulation factor (BF) of trace elements was markedly variable among the different plant species. On average, the BF for various trace elements was in the following decreasing order: Zn > Cu > Mn > Ni > As > Pb > Cr. The translocation factor among the investigated plant species was also considerably variable and showed the following decreasing order: Mn > Zn > Ni > Cu > Cr > As > Pb. Several hyperaccumulating plants were identified: Artemisia vulgaris for As, Mn and Zn, Phalaris arundinacea for Mn and Ni, Heracleum sphondylium for Cr and Zn, and Bistorta officinalis for Mn and Zn. The marked accumulation of trace elements in the plant tissue suggests that the site may not be suitable for urban agricultural production. The plant tissue-borne trace elements could affect microbial activities and consequently interfere with the ecosystem functioning in the affected areas.

Criterion for the assessment of the ecological condition of bottom sediments (on the example of the Brest region)

Geochemical parameters of bottom sediments allow quick estimating the state of the environment within the catchment of watercourses, as the composition of bottom sediments inherits the geochemical features of the components of the surrounding landscape. New data on the content of trace elements, sulfates, chlorides, nitrates, petroleum products, synthetic surfactants and phenols in the bottom sediments, obtained during complex geochemical studies in the Brest region, are presented. The concentration levels of the determined ingredients for sediments of the main types of reservoirs were determined. The maximum accumulation of nitrogen compounds, chlorides, phosphates and trace elements (nickel, cobalt, vanadium, chromium, copper, zinc and manganese) was marked in the sediments of rivers, while sulfates and lead are concentrated to a greater extent in the bottom sediments of the drainage channels. The map of pollution of bottom deposits of the territory of the Brest region of scale 1:200000 was constructed. It was found that the geochemical state of bottom sediments in the reservoirs of the Brest region is mainly in satisfactory condition, the degree of pollution by heavy metals was estimated as permissible with only 3.0 % belonging to the category of dangerous pollution level.

High-resolution elemental mapping of the root-rhizosphere-soil continuum using laser-induced breakdown spectroscopy (LIBS)

Understanding the complex chemical nature of root-soil interactions is essential for building the next generation of sustainable agricultural systems and facilitating long-term environmental remediation strategies. Techniques currently suited to investigate spatial controls on nutrient exchange in plant rhizospheres, however, are hindered by limitations in throughput, cost, analytical scope, and sample preparation needs. We describe here a method for rapid, high-resolution (∼100 μm), multi-element imaging of both organic content and inorganic constituents in root-rhizosphere-soil systems using laser-induced breakdown spectroscopy (LIBS). A switchgrass assemblage (Panicum virgatum) was grown in compact rhizotrons containing a sandy loam Alfisol from the Kellogg Biological Station (KBS), Michigan, USA. Root-soil samples were extracted using custom plastic coring devices for live root sampling and a modified drill press for sectioning frozen stabilized soil. A 266 nm, Nd:YAG laser was rastered over ∼10 mm2 sample surfaces and broadband spectra from single-pulse ablations were collected and mapped to discrete XY spatial coordinates for simultaneous imaging of 17 macronutrients, micronutrients and matrix elements. In order to rapidly process LIBS raster data and investigate chemical trends in the rhizosphere, an open-source Python module was developed, in which we used a novel calibration-free masking algorithm (based on principal components analysis (PCA) of normalized spectral intensities) to discriminate soil mineral grains, root fragments, and associated rhizosphere regions. We observed fine-scale chemical gradients within only a millimeter of switchgrass roots, consistent with rhizodeposition of organic compounds and proximal uptake of inorganic nutrients. Detection of trace element and carbon accumulations with diagnostic spectral signatures in the rhizosphere suggested the presence of residues (detritusphere) that could serve as sites of preferential microbial accumulation. These results highlight potential applications of LIBS within the growing field of spatially-resolved plant-soil analysis and extend its versatile imaging capabilities to the complex root-rhizosphere-soil network.

Age and diet-specific trace element accumulation patterns in different tissues of chub (Squalius cephalus): Juveniles are useful bioindicators of recent pollution

Chub (Squalius cephalus L. 1758) specimens of three age groups with different types of diet were collected in November 2013 in the River Szamos/Someş, Hungary. The Ca, K, Mg, Na, Cd, Cr, Cu, Fe, Mn, Pb, Sr and Zn concentrations were analyzed in the muscle, gills and liver samples of chub by microwave assisted plasma-atomic emission spectrometry (MP-AES). The Kruskal–Wallis test revealed significant differences among different age groups based on the trace element concentrations in the liver, muscle and gills. The trace element concentration pattern in muscle and liver of different age groups differed, may be according to the different diet types of the groups. Meanwhile no differentiation among the age groups based on the trace element concentration in the gills was observed, probably because the pattern of trace elements in the gills is related to the habitat preference, which does not differ during the life-span of chub. In contrast to expectations, trace element concentrations in juveniles were the highest in most cases, certainly because of their specific diet, relatively fast metabolic rate and inadequately developed detoxification system. Only the copper concentrations in liver increased with fish age. Considerable concentrations of trace elements in the tissues of juveniles were observed in the case of elements whose concentrations in the River Szamos were higher in 2013 than in previous years. According to this phenomenon, trace element patterns in the tissues of juveniles may be good indicators of recent pollution of watercourses.

Zn, Co, Cr, As, and genotoxic effects in the ichthyofauna species from polluted and non-polluted/protected estuaries of the São Paulo coast, Brazil

Abstract: The human impact on estuarine regions results in an increasing concentration of trace elements in the environment, exposing aquatic organisms. In this study, Zn, Co, Cr, and As were determined in the muscle tissue of some fish species from Santos-Sao Vicente (SSV), a recognized polluted region, and in the Cananeia estuary (CAN). Genotoxicity was also determined for the evaluation of the chronic effect on ichthyofauna, to enlarge the bank of environmental data regarding the effects of pollution, and to suggest other fish bioindicator species that may contribute to monitoring programs. The obtained data showed a similar profile of an accumulation of Co and Zn in Micropogonias furnieri and Chaetodipterus faber, where: Santos Bay > CAN > inner area of SSV. A low frequency of micronucleus was observed. However, in general, fish from the inner area of the SSV estuary presented more nuclear abnormalities than fish from Santos Bay and CAN. In the inner area of SSV, Centropomus paralelus and Diapterus rhomneus showed more changes than other fish species. It was possible to consider that the habits of each species, contributed to a different profile of trace element accumulation, followed by the chemical components in the organism offering different vulnerability.

Accumulation of trace elements by corn (Zea mays) under irrigation with treated wastewater using different irrigation methods

Treated wastewater reuse for irrigation has gained a greater significance as an alternative resource to meet the growing water demands for agriculture and reduce the pressure on limited existing fresh water. However, this reuse needs adapted management in order to avoid environmental and health risks. An experiment was conducted in a greenhouse to evaluate the effect of different irrigation methods on the Metallic Trace elements and metals concentrations of a Tunisian soil (pH = 8.6) and corn when using treated wastewater. Four irrigation methods: surface irrigation, sprinkler irrigation, drip irrigation and subsurface drip irrigation, and two water qualities were used: treated wastewater and fresh water. Samples of soil and corn were analyzed for several Metallic Trace elements. Results for soil showed that treated wastewater increased electrical conductivity, nutrients and metallic trace elements. The highest levels of salinity and Metallic Trace elements were recorded with using surface irrigation and the lowest were noticed by using subsurface drip irrigation. Whereas the highest levels of nutrients elements were recorded by using subsurface drip irrigation. Results for corn showed that irrigation with treated wastewater improved corn biomass, increased nutrient elements, nitrate reductase activity and chlorophyll content. The concentrations of Metallic Trace elements in different parts of corn were significantly higher under treated wastewater irrigation than fresh water irrigation and were reduced in case of subsurface drip irrigation. Among studied metals, Nickel concentration exceeded the permissible limits of 10 mg kg−1. Bio-concentration factor values were, in order, Iron > Zinc > Nickel > Copper > lead > Cadmium, whereas, translocation factor values were, in order, Copper > Zinc > Cadmium > iron > lead > Nickel. Because of translocation factor < 1 and bio-concentration factor ≥ 0.2, maize could be considered as both an excluder and an accumulator plant. Results of this study indicate that the use of subsurface drip irrigation decreased the amount of soil and corn contamination by Metallic Trace elements.

Sediment and biota trace element distribution in streams disturbed by upland industrial activity.

Extensive industrial areas in headwater stream watersheds can severely impact the physical condition of streams and introduce contaminants. We compared 3 streams that received stormwater runoff and industrial effluents from industrial complexes to 2 reference streams. Reference streams provide a benchmark of comparison of geomorphic form and stability in coastal plain, sandy-bottomed streams as well as concentrations of trace elements in sediment and biota in the absence of industrial disturbance. We used crayfish (Cambarus latimanus, Procambarus raneyi, Procambarus acutus) and crane fly larvae (Tipula) as biomonitors of 15 trace elements entering aquatic food webs. Streams with industrial areas were more scoured, deeply incised, and less stable. Sediment organic matter content broadly correlated to trace element accumulation, but fine sediments and organic matter were scoured from the bottoms of disturbed streams. Trace element concentrations were higher in depositional zones than runs within all streams. Despite contaminant sources in the headwaters, trace element concentrations were generally not elevated in sediments of the eroded streams. However, element concentrations were frequently elevated in biota from these streams with taxonomic differences in accumulation amplified. In eroded, sand-bottomed coastal plain streams with unstable sediments, single snapshots of sediment trace element concentrations did not characterize well bioavailable trace elements. Biota that integrated exposures over time and space within their home ranges better detected bioavailable contaminants than sediment. Environ Toxicol Chem 2019;38:115-131. © 2018 SETAC.

Major and Trace Element Compositions of Hummocky Frozen Peatlands in the Forest–Tundra of Northeastern European Russia

The major and trace element compositions of stratified frozen peatlands in the forest–tundra of Northeastern European Russia were determined for the first time. The upper level of trace element accumulation was confined to the active (seasonally thawed) layer owing to airborne contamination over a long time span and related to the bioaccumulation of Hg, Cd, Pb, Cu, and other heavy metals (HMs) by plants and humus materials. The character of element accumulation and migration in the active layer is controlled by the stability of HM humates. Under high-acidity conditions, HMs are highly mobile and migrate to the lower boundary of the active layer, which is indicated by an increase in the fraction of water-soluble forms of a number of elements. Analysis with a scanning electron microscope revealed the presence of spherical and semispherical particles up to 1 μm in size containing Pb, Zn, Cr, and Ni in the upper peat levels, which indicates an anthropogenic source of their input owing to long-distance and local transport of air masses. The central level of element accumulation was confined to peat layers in the permafrost zone (60–120 cm), where enrichment in As and Cd relative to the mean contents in the Earth’s crust (and approximate permissible concentrations, APC, for soils) and accumulation of Fe, Al, S, and siderophile elements were observed. The source rocks of the peatlands are loams enriched in Cd, Zn, and As. The statistical analysis of relations of the contents of major and trace elements in the stratified peat horizons with the composition of peat-forming materials showed a significant contribution of the biogenic accumulation of elements.

Assessment of trace elements pollution in sea ports of New South Wales (NSW), Australia using macrophytobenthic plant Ecklonia radiata as a bio-indicator

In this study seaweeds (Ecklonia radiata) from six major sea ports of NSW, Australia were used as a bioindicator to assess the distribution and levels of trace elements accumulation in the ports compared to the background ecosystem. Bioconcentration ratio (BCR), biota sediment accumulation factor (BSAF), enrichment factor, multivariate statistical analysis and hierarchical cluster analysis were used to identify trace elements contamination. The results illustrate BCRs of Al, Fe, Mn, Zn, Pb, Cu, As and Ba in E. radiata whereas the BASFs portray boron enrichment in all sea ports along with bioaccumulation of As in Port Jackson and Pb in Port Botany. However, trace elements variations between studied and background locations was found to be significant for Port Kembla and Newcastle. The principal component analysis result explained four principal groups with 76.25% cumulative variance. Cluster analysis was further performed to detect major groups of elements and sites to portray interconnection between the contaminants and the locations.