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The contents of chemical elements in the alluvial soils (Fluvisols) in the middle reaches of the Bolshaya Kokshaga River have been studied, The parent material of these soils inherits its composition from sediments of the Central Russian and Cisuralian mineralogical and geochemical provinces. Limits of the bulk contents of elements and their background concentrations have been established, which forms the basis for the environmental monitoring in the Bolshaya Kokshaga Nature Reserve. In total, 34 elements have been determined in the alluvial soils and sands of shoreline shoals; the most abundant elements with concentrations above 1 g/kg are Si, Al, Fe, Ca, K, Mg, Na, Ti, Mn, P, and S. Element concentrations in different types of soils differ in a statistically significant manner. The highest similarity in the elemental composition is observed for meadow and mucky gley soils. As compared with the alluvial soils, the sands of shoreline shoals display the maximum content of Si and the minimum contents of other elements. Soddy soils are characterized by the low content of all elements, except for Si. Meadow and mucky gley soils accumulate larger amounts of Al, Fe, K, Na, Mg, Ti, Mn, Ba, Cr, Zn, Ni, V and As, while eutrophic peat soils (highly mineralized peat deposits) accumulate more Ca, S, P, Sr, Cl, and Rb. Concentrations of As, Cu, V, P, Zr, Ni, and Zn in the alluvial soils exceed their natural abundance in the Earth crust (clarke values) by 1.5–2 times (Kc = 1.5–2), while concentrations of Al, K, Mg, Ti, Sr, Rb, Na, Cl, and Ca are below their clarke values (Kc < 1); concentrations of other elements are comparable to clarke values. [ABSTRACT FROM AUTHOR]

Regional stream water geochemistry acquired as part of the Tellus programme in Ireland has been analysed to assess its potential for application to environmental assessment and mineral exploration. Interpolated geochemical maps and multivariate statistical analysis, including principal component analysis and random forest classification, demonstrate broad geogenic control of stream water chemistry, with both bedrock and subsoil contributing to the patterns observed. Surface water regulations set Environmental Quality Standard values for individual Priority Substances and Specific Pollutants that may depend on background concentrations and/or water hardness. The high resolution of Tellus stream water data and their location on low-order streams have allowed estimation of background concentrations and water hardness in the survey area, with significant implications for water monitoring programmes. Anthropogenic inputs to stream water in the survey area come mainly from agricultural sources and Tellus data suggest few catchments are unaffected. Comparison of Tellus stream water geochemistry with stream sediment and topsoil geochemistry suggest that stream water geochemistry has strong potential for use in mineral exploration, with the same base metal and gold pathfinder anomalies apparent in all three data sets. Cluster analysis indicates that base metals in stream water are associated with organic matter but statistical analysis may be employed to distinguish mineralization-related signatures. Supplementary material: Comparison of cation/anion associations using Piper plots and principal component analysis is available at https://doi.org/10.6084/m9.figshare.c.5683094 Thematic collection: This article is part of the Hydrochemistry related to exploration and environmental issues collection available at: https://www.lyellcollection.org/cc/hydrochemistry-related-to-exploration-and-environmental-issues [ABSTRACT FROM AUTHOR]

A Human-health Risk Assessment was performed for an agricultural site in North-East Italy undergone digestate application to (i) check the compliance of digestate land spreading with the Italian and European regulations on contaminated agricultural soils and (ii) evaluate how resulting risk estimations can be influenced by the applied modeling assumptions. The assessment estimated the risk related to adults and children intake of Heavy Metals (HM) contained in crops at concentrations estimated by a soil-plant transfer model based on the substance-specific soil-water partition coefficients. Eight different scenarios were investigated, according to different digestate type (from biowaste and agro-industrial byproducts), digestate application techniques and soil background concentrations. Non-risky situations resulted in all scenarios involving digestate application. The totality of calculated non-carcinogenic Hazard Indexes ( H I) and carcinogenic total risk ( RTOT C ) resulted below 0.02 and 3E10−9, respectively. In contrast with the definition, non-carcinogenic risks were associated with the considered soil background concentrations, with H I s up to 1.7 for child receptors, while carcinogenic risk was calculated below the concern threshold (i.e., RTOT C < 10−5). Accordingly, this study highlighted (i) non-concerning situations related with lawful application of digestates and (ii) the need to improve the modeling of bioavailability to plant of HMs background content of soil. [ABSTRACT FROM AUTHOR]

The strengthening of anthropogenic pressure on the catchments of small and medium-sized rivers of the Central Black Earth region of Russia, associated with significant plowing and an increase in the number of livestock complexes, contributes to an increase in the concentrations of organic substances and nutrients in permanent watercourses. At the same time, the sources of their point discharges are absent. This indicates an increase in diffuse pollution of rivers as a result of erosion-hydrological processes in economically developed catchment areas. The case of the formation of catastrophic pollution of the upstream reaches of the Psel (Psyol) River, which led to the mass death of aquatic organisms at the 25 km section of the river, is discussed. It was found that the reason for this is a catastrophic decrease in waterborne oxygen concentrations, caused by a combination of various active water-erosion processes in the plowed catchment area, related to anomalous rainfall, temperature regime, and hydrodynamic characteristics of this section of the river channel. It is shown that in the absence of measures aimed at soil and water protection on the catchments of small rivers of the Central Black Earth regions, in certain weather-climatic conditions, the diffuse water pollution of watercourses may reach a catastrophic level. [ABSTRACT FROM AUTHOR]

This study considers the daily values of gridded concentrations for NO 2 , O 3 , PM 10 and PM 2.5 in London and its surroundings over 2007–2011. A two-step procedure was used for concentration smoothing to observe the urban pollution island. In the first step, the elliptic fit was compared with fits from the Gaussian and Epanechnikov kernels. The results obtained for the Gaussian kernel were used to apply an elliptic fit and a Gaussian directional fit. Lamb weather types were also determined. As a result, the elliptic fit calculated extended concentrations against those calculated with the kernels, and the Gaussian kernel provided a smoother shape. NO 2 and O 3 presented the opposite distribution, and the urban pollution island was defined with contrasted concentration values between the city centre and the surrounding areas. The second smoothing simplified the urban shape and determined the background concentrations. The most frequent type was the anticyclonic, although the most contrasting result was obtained for the anticyclonic type with SE flow, since O 3 values were low compared to the high NO 2 values, thereby revealing pollution transport from the continent under this infrequent type. Finally, the urban pollution island shape is maintained for NO 2 and O 3 under the most frequent weather types. • The urban pollution island is observed for NO 2 and O 3 with smoothed concentrations • Particulate matter presents a weak city-surroundings contrast • The anticyclonic type prevails, whereas wind speed is high in westerly types • Pollution transport from the continent is infrequent • The PM 10 pollution island was observed under certain weather types and concentrations [ABSTRACT FROM AUTHOR]

Research on the concentrations of the metals Cu, Cd, Fe, and Mn showed no significant relationships between metal concentrations in water and in brown algae of the Sea of Japan with background concentrations. A significant correlation between metal concentrations in the environment and in the algae was found for zinc; it was the only metal with a wide variation in concentrations exceeding background levels in the habitat of macrophytes. Correspondingly, the only significant correlation between the bioaccumulation factor (BAF) of seaweeds from the Sea of Japan and the content of this element in seawater was found for zinc. It was shown for all studied metals that the highest and most variable BAF values for algae were observed within the background range of metal concentrations in the aquatic environment, which allows us to express the background range (the range caused by natural conditions) graphically. Thus, the high variability of the BAF values of aquatic organisms in the background environmental conditions necessitates very cautious interpretation of biomonitoring data. [ABSTRACT FROM AUTHOR]

Abstract The objective of this study was to determine the natural concentrations of Hg and Se in 45 representative soil profiles from the Cerrado biome in central Brazil, and to correlate their concentrations with soil chemical and physical characteristics. The study area was composed of three sub-regions: Goiás, Northwest of Minas Gerais, and Minas Gerais Triangle. Selenium and Hg concentrations were determined by acid digestion and atomic absorption spectroscopy. Data were subjected to analysis of variance on the means of the Hg and Se variables within each soil class at two depths, followed by multivariate statistical methods. The Hg concentrations ranged from 15 to 182 μg kg−1 and the Se concentrations ranged from 22 to 72 μg kg−1. The soil characteristics that most contributed to Hg concentrations in the soils, according to principal component analysis, were Fe 2 O 3 , FeO, TiO 2 , pH, P 2 O 5 , and effective CEC. In general, the soils of the Cerrado biome have deficient Se concentrations. The Humic Rhodic Acrustoxes have Hg concentrations above the prevention reference value for soils of Minas Gerais. Highlights • Natural Hg and Se concentrations in Cerrado soils are low. • Concentrations of Hg correlated positively with the main oxides found in tropical soils. • Humic Rhodic Acrustoxes may act as sinks to accumulate Hg. • The soils in this study are considered deficient in Se. [ABSTRACT FROM AUTHOR]

Abstract: Geochemical features of copper and zinc in soils of background landscapes of northeastern European Russia have been revealed. Soils of accumulative landscapes are enriched with copper and zinc compounds compared to those of eluvial landscapes. Humus horizons serve as a geochemical barrier for elements. Analysis of the sorption parameters of humic acids (HAs) shows that the actual content of the studied heavy metals (HMs) in soils is far from the maximum sorption capacity. The contribution of HAs to the total sorption of metals makes up 4% for copper and 21% for zinc. The distribution of HMs among the genetic horizons is more contrast in loamy automorphic soils than in sandy semihydromorphic and hydromorphic soils. Paired correlations have been revealed between the contents of copper and zinc in sandy and loamy soils, which points to the similarity of their biogeochemical migration in landscapes. An actual database has been created, which is foundational to schematic maps of the spatial distribution of elements in background soils. The geochemical assessment of the environmental status of soils has allowed establishing norms for the regional background contents of copper and zinc in taiga and tundra soils. [ABSTRACT FROM AUTHOR]

A study was made of the influence of extraction of lead and zinc ores in the northern part of Vietnam (the Red river basin, Chodon district of Bac Can Province, and the basins of the Dai, Ban Thi, Ta Dieng and Cau rivers). Background concentrations of macro- and microelements and biogenic elements are determined in the river waters and water extracts from bottom sediments of small streams of the study area. A significance exceedance of background concentrations was revealed in stretches of the headwaters of the Ban Thi and Dai rivers caused by a combination of natural and anthropogenic factors. It is established that the river waters near the pollution sources contain increased (compared with the geochemical background) concentrations of Zn, Pb, Fe, Ni, Co, As, Bi, Cd, Cs, Sb, Ag,NO2− and SO42−. The waters are estimated as moderately and heavily polluted, and at the other points as minimally polluted. It is determined that the level of accumulation of matter in water extracts from bottom sediments with respect to the geochemical background in the vicinity of the ore dressing factories corresponds to weakly and heavily polluted bottom sediments, and further downstream, to thy minimum level of pollution. It is shown that the influence of extraction of lead and zinc ores on the state of small streams is observed in stretches as long as 11-12 km (with a maximum in stretches of up to 4.5 km). The mathematical model of Pb and Zn distribution in the river waters of the study area has been developed and tested. [ABSTRACT FROM AUTHOR]

Total gaseous mercury (TGM) data from urban Nanjing, at the western edge of the Yangtze River Delta (YRD) region in China, over nine months, were analyzed for peak and background mercury concentrations. The background concentration of TGM was found to be 2.2 ng∙m−3. In examining episodic influences of free tropospheric air masses on the surface TGM concentrations in Nanjing, we hypothesize heterogeneity in the global distribution of TGM concentrations in the free troposphere. The nine-month averaged diurnal cycles of TGM indicate a strong co-emission with SO2 and an underestimation of greater than 80% TGM emissions in current inventories. Regular peak concentrations of mercury were investigated and the major causes were YRD emissions, transport from rural areas, and monsoonal transport. Transport of rural emissions is hypothesized to be from illegal artisanal small-scale gold mining that are currently missing in the emission inventories. Enhancement of TGM associated with summer monsoon contributed to a maximum TGM concentration in mid-May–early June, an inverse seasonality in comparison to most other observations in China, North America, and Europe.

A rapid, simple yet scientifically sound scheme providing two important types of information used in assessment of estuarine sediments is presented. The mean enrichment quotient (MEQ) (fine contemporary sediment metal concentration/fine fraction background metal concentration) for Cu, Pb and Zn provides the magnitude of human-induced change, (deviation from the pristine condition), while sediment quality guidelines (SQGs) assess the risk posed by sedimentary contaminants to the benthic community. Maximum metal enrichment for sediment in Sydney estuary (Australia) is > 100 times for Cu, Pb and Zn and the MEQ is > 10 times for most of the estuary. Adverse effect on benthic populations due to Cu, Pb and Zn are expected in 2%, 50% and 36% of the waterway, respectively. SQGs for contaminant mixtures predict ~ 2% of the estuary has the highest risk of adverse effects, while 25% has intermediate risk. The scheme is well suited to initial assessments of estuarine sediments worldwide. [ABSTRACT FROM AUTHOR]

Results of soil cover studies in different regions of the Russian North from the Kola Peninsula in the West and the Chuckchi Peninsula in the East are presented. Toxic metal distribution in soils (podzols, cryosols, histosols of different types) of both impact (technogenically disturbed) and background regions were studied. HCl and ammonium acetate (A/A) buffers were used as the extraction agent followed by atomic absorption spectrometry. More than 100 field sites were studied. It was demonstrated that microelement soil content is closely connected with that of parent rocks which differ in different regions. Noticeable increase of heavy metals (Cu, Ni, Co, Pb, Zn etc.) in the upper soil horizons is marked near large industrial sites (up to 20 km from the source of pollution) sometimes exceeding background for more than 10–100 times. Each region and soil type has its own background concentration level. That is why no general superregional background concentration patterns may be revealed based on numerous soil sampling in different regions of the discussed territory. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess levels of dioxins (polychlorinated dibenzo-p-dioxins and dibenzofurans, PCDD/Fs) and dioxin-like polychlorinated biphenyls (PCBs) (DL-PCBs) in food of animal origin produced in the Netherlands, including potential trends in time. Test results from about 2500 samples of animal derived food products (beef, veal, lamb, chicken, pork, deer, milk and eggs), sampled for the National Residue Monitoring Plan from 2001–2011, were evaluated. Most samples were screened with a bioassay and, if suspected, analysed by GC-HRMS. The fraction of samples which were non-compliant with European maximum levels was rather low, being below 1% for most food products, except for lamb. Exceedance of action levels was particularly observed for lamb and beef. To obtain an insight into background levels, a randomly taken part of the samples was directly analysed by GC-HRMS. In general, only minor decreases in mean PCDD/F and DL-PCB concentrations could be observed for the period 2001–2011. This may be due to a plateauing of current background levels but also to factors like the sensitivity of the analytical method. [ABSTRACT FROM PUBLISHER]

Since 2009, the measurement of the background concentration of the fine particle fraction has been a part of the climate-monitoring program of the German Meteorological Service (DWD). These particles are of high health relevance as a critical air pollutant affecting processes like the scattering and absorption of solar radiation and influencing cloud formation and visibility. At 12 weather stations, the coarse (2.5 to 10 l m) and the fine particle fractions (PM2.5) are measured by means of passive and active samplers. First results are presented for the mass concentrations of coarse and fine particles as well as for the black carbon (BC) content and the concentration of certain inorganic ions of fine particles. There is not only a seasonal correlation between the fraction of fine and coarse particles, but also a correlation with the location (urban background or rural background). With the help of light microscopy, coarse particles can be differentiated for a geogenic (predominantly wind blown mineral and sea salt particles of natural origin and road abrasion) and for an anthropogenic opaque component (combustion residues, e.g. fly ash and non-exhaust vehicle emissions, e.g. abrasion particles of brakes and tires). Measuring the fine fraction and the coarse fraction separately instead of PM10 allows for a better source allocation and thus is a more appropriate method for the improvement of the air quality in, e.g. low emission zones.

Copper distribution, natural background and contamination levels in sediments of the Galician rias were assessed from 389 surface sediment samples and five sediment cores. The natural reference concentration of copper can be estimated using the Cu-Fe relationship obtained from preindustrial sediments of rias: [Cu (mg kg–1)] / [Fe (g kg–1)] = 0.55. Severe copper contamination was mainly observed in the harbour, fishing ports and shipyards near shore areas of the Galician coast. Therefore, the rias of Ferrol and Vigo were the most environmentally disturbed, while the northern Galician rias were the least disturbed. The Galician case can be seen as the type of copper contamination due to maritime activities observed in other world harbours.

This work evaluates the mercury (Hg) contamination status (sediments and biota) of the Bijagós archipelago, off the coast of Guinea-Bissau. Sediments exhibited very low concentrations (< 1–12 ng g −1 ), pointing to negligible sources of anthropogenic Hg in the region. Nevertheless, Hg is well correlated to the fine fraction, aluminium, and loss on ignition, indicating the effect of grain size and organic matter content on the presence of Hg in sediments. Mercury in the bivalves Tagelus adansoni and Senilia senilis did not vary considerably among sites, ranging within narrow intervals (0.09–0.12 and 0.12–0.14 μg g −1 (dry weight), respectively). Divergent substrate preferences/feeding tactics may justify slight differences between species. The value 11 ng g −1 is proposed as the sediment background concentration for this West-African coastal region, and concentrations within the interval 8–10 ng g −1 (wet weight) may be considered as reference range for S. senilis and T. adansoni in future monitoring studies. [ABSTRACT FROM AUTHOR]

Metals such as arsenic (As), cadmium (Cd), copper (Cu), chromium (Cr), nickel (Ni), lead (Pb), vanadium (V), have been determined in species of Mediterranean marine organisms collected from areas supposed to be at background contamination levels. The Inductively Coupled Plasma Mass Spectrometry (ICP-MS) approach was adopted for the determination of all the metals. Arsenic, Cd and Pb determined in the 42 samples, do not exceed the pertinent maximum level except a sample of hake. In wild fish, the concentration range for Cr, Ni, V and Cu was, respectively: 0.07–0.09, 87.6–124, 0.022–0.075 and 0.79–1.74 μg/g fresh weight (fw). The farmed fish samples show concentration levels below the wild fish ones, except for Cr which range at the same levels. Cadmium and Pb show a high sample number under the quantification limit. The elements do not bio-magnify among the species considered and appear to show low variations in relation to organisms’ position in the food chain and at sampling sites. [ABSTRACT FROM AUTHOR]

[Display omitted] • Background trace metal concentrations were determined for marine sediments. • Higher accumulation rates of trace elements occurred since the 1950 s. • Concentrations of some trace metals were above the threshold effect level. • There is no evidence for human-mediated heavy metal contamination. Trace elements are pollutants that can be released into the environment and cause adverse effects to ecosystems and human health. Once released into the environment, they can be dispersed by the wind and deposited in soils and sediments of both marine and inland aquatic systems. After entering the food web, trace elements can accumulate at harmful concentrations in higher trophic levels, including humans. Background concentrations of trace elements such as As, Co, Cr, Cu, Ni, Pb, V and Zn were measured in sediment cores from pristine marine environments near Panama. Temporal records of trace element concentrations and fluxes were determined for the period 1906 to 2017, using the 210Pb dating technique. Higher accumulation rates of trace elements since the 1950s were attributed to an increase in human activities and climate shifts. The enrichment factor in cores was < 2, indicating there has been no substantial human-mediated contamination, and that trace elements were derived mainly from lithogenic sources. Nevertheless, the Threshold Effect Level and Probable Effect Level (TEL and PEL) indicated that Cr, Cu, As, and Ni can pose a risk to biota and therefore to humans, even at natural concentrations. Periodic monitoring of marine environments is recommended to minimize human health risks, reduce detrimental effects to biota, and promote monitoring of human activities that have the potential to cause trace metal contamination. [ABSTRACT FROM AUTHOR]

Implementation of geological CO 2 storage requires monitoring for potential leakage, with an essential part being establishment of baseline CO 2 in soil gas. CO 2 concentrations and weather parameters were monitored for ∼2 years at three locations in the Netherlands. CO 2 concentrations in soil ranged from 0.1 to 28% and were variable with site, depth and soil type. Statistical models (based on weather parameters) corresponded well with the measured CO 2 time-series, having best fit with soil temperature. This method can detect large CO 2 anomalies, however not smaller leakages. The monitoring method is robust and low-maintenance, making it a relatively low-cost surveillance possibility. [ABSTRACT FROM AUTHOR]

The unit area background discharges of total nitrogen from the catchment areas of some unmonitored and partially monitored rivers of the Gulf of Finland basin and background concentrations of total nitrogen in waters of these rivers were estimated. [ABSTRACT FROM AUTHOR]

Data on fluorine concentration in water in the Middle Klyaz'ma Basin during summer low-water period have been obtained. Fluorine background concentration has been determined in streams (Klyaz'ma R., small rivers, and creeks), water bodies (drainage ditches, lakes), and subsoil waters. Anthropogenic fluorine hydrochemical anomalies have been determined and localized with respect to urbanized industrial areas. An assumption has been made and experimentally substantiated, according to which fluorine concentration in subsoil water is governed by the processes of its distribution between water and host rocks. It has been established that the interaction of soils with snowmelt water and alluvial deposits with river water in neutral and acid media is accompanied by fluorine removal from solution, while in a weakly alkaline medium, fluorine passes from solid phase into solution. The effect of dissolved organic matter on the process of fluorine leaching from rock minerals also depends, primarily, on the equilibrium pH value: in weakly alkaline media, the presence of organic acids contributes to fluorine mobilization, while in weakly acid media, it reduces mobilization rate. [ABSTRACT FROM AUTHOR]

Total gaseous mercury (TGM) data from urban Nanjing, at the western edge of the Yangtze River Delta (YRD) region in China, over nine months, were analyzed for peak and background mercury concentrations. The background concentration of TGM was found to be 2.2 ng·m-3. In examining episodic influences of free tropospheric air masses on the surface TGM concentrations in Nanjing, we hypothesize heterogeneity in the global distribution of TGM concentrations in the free troposphere. The nine-month averaged diurnal cycles of TGM indicate a strong co-emission with SO2 and an underestimation of greater than 80% TGM emissions in current inventories. Regular peak concentrations of mercury were investigated and the major causes were YRD emissions, transport from rural areas, and monsoonal transport. Transport of rural emissions is hypothesized to be from illegal artisanal small-scale gold mining that are currently missing in the emission inventories. Enhancement of TGM associated with summer monsoon contributed to a maximum TGM concentration in mid-May--early June, an inverse seasonality in comparison to most other observations in China, North America, and Europe. [ABSTRACT FROM AUTHOR]

The evaluation of the background flow modules of total (unfiltered) phosphorus catchment areas a number of uncontrolled and partially controlled drainage basin of the Baltic Sea and the background concentrations of total phosphorus in the waters of the rivers under consideration. [ABSTRACT FROM AUTHOR]

A comprehensive environmental evaluation was completed on 20 metals: two reference metals (Fe, Al) and several minor trace metals (As, Ba, Co, Cr, Cu, Mn, Ni, Pb, V, and Zn) for surface soils and sediments collected from 50 sites in Everglades National Park (ENP), the coastal fringes of Biscayne National Park (BNP), and Big Cypress National Preserve. Samples were prepared by acid digestion (EPA3050) and analyzed by ICP/MS detection (EPA6020). Although no widespread contamination was detected across the two parks and one preserve, there were some specific areas where metal concentrations exceeded Florida's ecological thresholds, suggesting that some metals were of concern. A screening-level evaluation based on a proposed effect index grouped trace metals by their potential for causing negligible, possible, and probable effects on the biota. For example, Cu in BNP and Cr and Pb in ENP were considered of concern because their adverse effect likelihood to biota was assessed as probable; consequently, these trace metals were selected for further risk characterization. Also, stations were ranked based on a proposed overall contamination index that showed that: site BB10 in BNP and sites E3 and E5 in ENP had the highest scores. The first site was located in a marina in BNP, and the other two sites were along the eastern boundary of ENP adjacent to current or former agricultural lands. An assessment tool for south Florida protected lands was developed for evaluating impacts from on-going Everglades restoration projects and to assist State and Federal agencies with resource management. The tool consists of enrichment plots and statistically derived background concentrations based on soil/sediment data collected from the two national parks and one preserve. Finally, an equally accurate but much simplified approach is offered for developing enrichment plots for other environmental settings. [ABSTRACT FROM AUTHOR]

Heavy metals occur naturally in soil, at concentrations that depend on the parent material from which the soil was formed, the processes of formation, and the composition and the proportion of the components of its solid phase. Quantifying these concentrations is important for environmental studies of soil contamination and pollution, and choosing the methods for doing so is a key step in establishing heavy metal contents in soil samples. We evaluated two digestion methods (aqua regia and EPA 3051, both microwave oven-assisted) for assessing pseudo-total concentrations of Cd, Co, Cr, Cu, Ni, Pb and Zn in the surface layer (0-20 cm) of soil samples from the Brazilian agricultural frontier in the southwestern Amazon. Nineteen composite samples of the most representative soil classes for the states of Mato Grosso and Rondônia were collected under native vegetation undisturbed by human intervention. Canonical discriminant analysis and principal component analysis were used for multivariate exploration of the data. Aqua regia extracted higher amounts of Co, Ni, Pb, and Zn than EPA 3051, while levels of Cr and Cu did not differ between methods. In general, aqua regia recovered more of the metals when compared to reference soil samples. [ABSTRACT FROM AUTHOR]

The aim of this research paper is the introduction of a novel mathematical approach to improve the accuracy of the results of air pollution dispersion models based on the calibration of input background concentrations. Using the Dunkirk area of the City of Nottingham in the UK as a case study, an air pollution model in ADMS-Roads was created for developing the mathematical approach. The iterative application of this approach to the input background concentrations effectively reduced the error between not only the annual mean, but also the hourly, calculated and monitored air pollution concentrations. The traffic flow profiles of the modelled road network were included in the air pollution model and their impact on the model results, after the application of the calibration approach, was investigated. The inclusion of the traffic flow profiles reduced further the error between the hourly, but not the annual means of, calculated and monitored concentrations. [ABSTRACT FROM AUTHOR]

Abstract: This study provides data concerning the hydrography and water chemistry of the Atlantic region between 29–38° N and 27–31° W, and establishes background values for dissolved Cu, Cd, Pb and As. Three water masses were identified: the Eastern North Atlantic Central Water (ENACW), the Mediterranean Water (MW) and the North Atlantic Deep Water (NADW). The ENACW exhibits a clear meridional gradient of temperature and salinity, with comparatively high values at the southern sites and lower values on the Azores platform. The ENACW, which includes the euphotic zone, also had comparatively high concentrations of oxygen and lower concentrations of nutrients and metals. The Cu, Cd and Pb results suggest that new background concentrations for OSPAR Region V (the Wider Atlantic) should be established as follows: 0.15–13nM for Cu, 0.05–1.4nM for Cd and 0.03–5nM for Pb. The background concentrations of As for OSPAR Region V should be 7–28nM. [Copyright &y& Elsevier]

The concentration of nitrogen dioxide (NO) in background air varies temporally and spatially and is influenced by meteorological and anthropogenic factors. Background concentrations used in local air quality modelling studies have a significant effect on the accuracy of the overall result and when based on short-term monitoring data, variation in concentrations with air mass history is often unaccounted for. The current paper presents a powerful tool for the quantification and separation of local and regional air mass effects on background air quality. The origin of and the regions traversed by an air mass prior to reaching a receptor has been modelled using HYsplit-4. Trajectories (between 12 and 96 h duration) were defined based on the frequency with which they passed into 16 predefined compass quadrants and each represented as a vector. Using this vector as the predictor variable and the background concentration as the response variable, non-parametric regression using a Gaussian kernel function was carried out. A graphical output indicated the trajectory direction of maximum NO concentration, while allowing distinction to be made between spurious and true peaks. In all cases, air mass history was found to have a statistically significant effect on NO concentrations. Incorporating emissions data into the analysis local and regional effects were separated and quantified. It was found that emissions in the UK and Europe have a significant effect on background NO concentrations in Ireland and in some instances supersede domestic emissions. The methods can be used to identify source regions, separate local and regional effects and improve predictions of background concentrations based on limited monitoring data. In particular, the results highlight the importance of considering air mass history when assessing background concentration levels for use in local air quality modelling studies. [ABSTRACT FROM AUTHOR]

Abstract: Thirty soil profiles from the agricultural area of Fray Mamerto Esquiú (Catamarca, Argentina) were investigated, and the variability in the natural background levels of seven heavy metals (e.g., Cd, Cr, Cu, Mn, Ni, Pb and Zn) was examined. Sampling sites with minimal anthropogenic influence were selected, and soil profile samples were analysed for major and trace element content. The soil samples were collected from every horizon in each profile, and the samples were digested using the aqua regia and DTPA methods for pseudototal and available heavy metals, respectively. A clear distinction was found between the metal content of the soils developed in each Reference Soil Group: the A-horizon reflects the complex interplay between the atmosphere, biosphere and lithosphere; the B-horizon can be used to study the influence of soil-forming processes; and the C-horizon represents the composition of the parent material at each sample site. The occasional or continuous addition of sediments to soil profiles, as well as organic matter accumulation and humification, make up the soil-forming processes of the greatest importance to the distribution of pseudototal heavy metals. The upper limits of the background levels, which help distinguish between natural and anomalous element concentrations, are presented. The heavy metal with the greatest number of samples and slight enrichment anomalies is Cd. Slight enrichment anomalies in Cd, Cr, Cu, Pb and Zn were detected in profile 29, confirming anthropogenic contamination. The results of this study confirm the importance of the local determination of background concentrations. The percentage of organic matter is the determining factor in the presence and distribution of the metals (Cu, Fe, Mn and Zn) available in the soils of the studied area, the top horizon having the greatest accumulation. ZnDTPA is the only available metal that also shows differences associated with soil salinity. However, the geochemical soil conditions imply low extractability, suggesting the plants in Fray Mamerto Esquiú have difficulty with micronutrient absorption. [Copyright &y& Elsevier]

Abstract: The seasonal intensive field measurements of gaseous and particulate polycyclic aromatic hydrocarbons (PAHs) were carried out at the Gosan international background site from November 2001 to August 2003. The annual average concentrations of gaseous and particulate PAHs are 1.4ngm−3 and 2.9ngm−3 (∑14PAH), respectively. Distinct seasonal variations exist with the highest concentration in winter and the lowest concentration in summer. In comparison with other places in Korea and other countries, the most distinguishing features at Gosan are the significantly low concentrations of low-molecular weight gaseous PAHs. In addition, noticeably high particulate PAH concentrations measured at urban and background areas in Korea could represent the regional characteristics of East Asia under the influence of high emission from China. The BaP equivalent concentrations (BaPeq) at Gosan, which are based on the US EPA’s toxicity equivalency factors for carcinogenic PAHs, are much higher than those at coastal or background sites in USA and Europe, and even comparable with that at urban sites in Europe. The possibility of more aged PAHs in the atmosphere associated with the long range transport of PAHs during winter period was suggested. It was found that larger fraction of non-exchangeable PAHs had strong influence to the gas/particle partitioning of PAHs at Gosan. [Copyright &y& Elsevier]

This study is focused on the assessment of potential health benefits by meeting the air quality limit values (2008/50/CE) for short-term PM10 exposure. For this purpose, the methodology of the WHO for Health Impact Assessment and APHEIS guidelines for data collection were applied to Porto Metropolitan Area, Portugal. Additionally, an improved methodology using population mobility data is proposed in this work to analyse number of persons exposed. In order to obtain representative background concentrations, an innovative approach to process air quality time series was implemented. The results provide the number of attributable cases prevented annually by reducing PM10 concentration. An intercomparison of two approaches to process input data for the health risk analysis provides information on sensitivity of the applied methodology. The findings highlight the importance of taking into account spatial variability of the air pollution levels and population mobility in the health impact assessment. [ABSTRACT FROM AUTHOR]

Abstract: Background concentrations of nitrogen dioxide (NO2) are not constant but vary temporally and spatially. The current paper presents a powerful tool for the quantification of the effects of wind direction and wind speed on background NO2 concentrations, particularly in cases where monitoring data are limited. In contrast to previous studies which applied similar methods to sites directly affected by local pollution sources, the current study focuses on background sites with the aim of improving methods for predicting background concentrations adopted in air quality modelling studies. The relationship between measured NO2 concentration in air at three such sites in Ireland and locally measured wind direction has been quantified using nonparametric regression methods. The major aim was to analyse a method for quantifying the effects of local wind direction on background levels of NO2 in Ireland. The method was expanded to include wind speed as an added predictor variable. A Gaussian kernel function is used in the analysis and circular statistics employed for the wind direction variable. Wind direction and wind speed were both found to have a statistically significant effect on background levels of NO2 at all three sites. Frequently environmental impact assessments are based on short term baseline monitoring producing a limited dataset. The presented non-parametric regression methods, in contrast to the frequently used methods such as binning of the data, allow concentrations for missing data pairs to be estimated and distinction between spurious and true peaks in concentrations to be made. The methods were found to provide a realistic estimation of long term concentration variation with wind direction and speed, even for cases where the data set is limited. Accurate identification of the actual variation at each location and causative factors could be made, thus supporting the improved definition of background concentrations for use in air quality modelling studies. [Copyright &y& Elsevier]

Geochemical background concentrations of potentially harmful elements and species (PHES) may have a high spatial variability and their natural levels can be higher than those caused by anthropogenic sources of pollution. Therefore, the use of a threshold value for assessing contamination can be inadequate and local variability should be considered. In Europe, soil quality standards are widely variable. In Italy concentration levels exceeding threshold values (TVs) are allowed only if the natural concentrations for a given area are higher than those specified by law. For sediments, in Italian law TVs have not been yet established but TVs with local validity are used for contamination assessment in areas with different geochemistry. A short outline of the worldwide regulatory frameworks is presented with the intent of singling out suitable approaches and priority actions needed to tackle the weak points in law, following the indications of the scientific community and stressing the importance of assessing the real hazard using tools for the evaluation of site-specific mobility and toxicity of PHES. Cases of areas with high PHES background concentration are presented as evidence of this widespread phenomenon and of the need to find effective approaches and solutions. [ABSTRACT FROM AUTHOR]

Data on concentrations of heavy metals (As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, V and Zn) in moss collected on the lightly industrialized territory of Lithuania and on the highly industrialized territory of the Czech Republic in 1995, 2000 and 2005 is used to separate the background and anthropogenic contributions to heavy metal concentrations in moss. The distribution of the concentration logarithms allowed us to determine a background mode, and to estimate the background concentration of heavy metals from this mode. The method was then applied for an estimation of the contribution of local sources to the total pollution level in both countries. The average concentrations and the background modes of heavy metals in Lithuania and in the Czech Republic were very similar, except in the case of vanadium, where the background concentration was higher in Lithuania than in the Czech Republic. For most elements, the background concentration in moss had a decreasing tendency in Lithuania and in the Czech Republic between 1995 and 2005, though the concentration of Cu and Hg increased in Lithuania. The variability of chromium concentration in moss differed from the remaining investigated elements in the Czech Republic, and it was expressed as a bimodal lognormal distribution. This variability may be due to simultaneous contamination of moss by chromium from soil and from industrial sources of pollution. [Copyright &y& Elsevier]

Abstract: The concentrations of twenty four chemical elements in the surface layer of natural desert soils and the cultivated farmland soils were measured at a desert-oasis ecotone in the middle of Heihe river basin, north-west China. Background values were estimated for (a) major elements (Si 335.3 g kg−1, Al 49.4 g kg−1, Fe 19.1 g kg−1, Ca 29.4 g kg−1, Mg 8.9 g kg−1, K 20.1 g kg−1, Na 17.5 g kg−1 and P 0.338 g kg−1), (b) heavy metals and non-metals (Cr 55.8 mg kg−1, Mn 404.8 mg kg−1, Ni 17.7 mg kg−1, Cu 5.1 mg kg−1, Zn 33.7 mg kg−1, Pb 15.5 mg kg−1 and As 5.2 mg kg−1) and (c) other trace elements (Ti 2.0 mg kg−1, V 55.3 mg kg−1, Co 5.7 mg kg−1, Rb 82.4 mg kg−1, Sr 232.9 mg kg−1, Y 14.7 mg kg−1, Zr 194.9 mg kg−1, Nb 7.8 mg kg−1 and Ba 720.6 mg kg−1). After natural desert soil was cultivated for agricultural use, significant changes in element concentrations occurred under tillage, irrigation and fertilisation management. Compared to natural soil, the for the levels of Si, K, Na, Sr, Zr and Ba decreased, and no changes were observed for Rb, while the values of the other 17 elements increase in agricultural soil from 1.2 to 3.5 times. However, their absolute concentrations are still low, suggesting that the arable soil in this region remains comparatively a clean soil. The increased silt, clay and organic carbon content, under long-term irrigation, enriched the fine-grained materials, and application of fertilisers and manure contributed to the accumulation of most elements in arable soil. The accumulation of elements in agricultural soil increased with increasing cultivation years and extent of soil development. [Copyright &y& Elsevier]

Abstract: The CALINE4 model is widely used to predict the effect of vehicle emissions on ambient concentrations close to roadways. It requires an evaluation of the rate at which different air pollutants are emitted by vehicles, taking into account things such as vehicle flow, velocity, type and age. For Europe the databases of the COmputer Program to calculate Emissions from Road Transport (COPERT) are combined with local vehicle details to obtain site-specific emission factors for dispersion modelling. The ability of CALINE4 to predict the spatial variation of hydrocarbon concentrations downwind of a motorway is assessed, as is the accuracy of COPERT III composite emission factors for several hydrocarbon compounds. The concentrations of seven traffic-associated compounds is found at three locations downwind and upwind of a motorway. Modelled and measured background-corrected downwind concentrations are compared on three bases: daily peak hour concentrations, mean concentrations, and a set of model evaluation parameters. [Copyright &y& Elsevier]

Osmium (Os) concentrations and 187Os/188Os isotope abundance ratios are presented for sedimentary materials, soils, humus, plants, mushrooms, mosses and lichens collected in the vicinity of the town of Luleå, Northeast Sweden, the data for biological specimens being the first reported. Contributions from sampling and varying exposure time to the observed environmental variability were evaluated. Sedimentary materials (from both fresh and brackish water) are most elevated in radiogenic 187Os, followed by inorganic soil horizons, mushrooms and humus. The Os isotopic compositions of plants, mosses and lichens are much less radiogenic, with mean 187Os/188Os lying within a relatively narrow 0.3–0.6 range. Significant temporal variations in Os concentrations and isotopic compositions of plant samples are attributed to integrative uptake of airborne Os with non-radiogenic composition. Measured Os concentrations in biological matrices increase in the order: small shrub leaves (blueberry and lingonberry)≤spruce needles≤mushrooms≤tree leaves≤pine needles

Osmium (Os) concentrations and 187Os/188Os isotope abundance ratios measured in epiphytic lichens from Northeast Sweden have been used for the identification of anthropogenic emission sources of this element. Based on isotope abundance ratios and similarities in spatial distributions between Os and chromium, smelters operated on chromium ores from Kemi deposits have shown to be the most important factor affecting the airborne Os burden in the region. The extent of the exposure is reflected by lichen concentrations near the source exceeding those from remote areas by a factor of 1000. Contributions from metal foundries processing iron, copper, lead and zinc ores can also be seen, though, because of lower Os concentrations in the feedstock, on a considerably lower scale. Masked by these industrial emissions in the studied area, the impact of Os originating from automotive catalytic converters cannot be resolved at present. [Copyright &y& Elsevier]

Trace elements may present an environmental hazard in the vicinity of mining and smelting activities. However, the factors controlling their distribution and transfer within the soil and vegetation systems are not always well defined. Total concentrations of up to 15,195 mg . kg –1 As, 6,690 mg . kg–1 Cu, 24,820 mg . kg–1 Pb and 9,810 mg . kg–1 Zn in soils, and 62 mg . kg–1 As, 1,765 mg . kg–1 Cu, 280 mg . kg–1 Pb and 3,460 mg . kg –1 Zn in vegetation were measured. However, unusually for smelters and mines of a similar size, the elevated trace element concentrations in soils were found to be restricted to the immediate vicinity of the mines and smelters (maximum 2–3 km). Parent material, prevailing wind direction, and soil physical and chemical characteristics were found to correlate poorly with the restricted trace element distributions in soils. Hypotheses are given for this unusual distribution: (1) the contaminated soils were removed by erosion or (2) mines and smelters released large heavy particles that could not have been transported long distances. Analyses of the accumulation of trace elements in vegetation (median ratios: As 0.06, Cu 0.19, Pb 0.54 and Zn 1.07) and the percentage of total trace elements being DTPA extractable in soils (median percentages: As 0.06%, Cu 15%, Pb 7% and Zn 4%) indicated higher relative trace element mobility in soils with low total concentrations than in soils with elevated concentrations. [ABSTRACT FROM AUTHOR]

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Abstract: It is important to establish contaminant levels that are normally present in soils to provide baseline data for pollution studies. Mercury is a toxic element of concern. This study was aimed at assessing baseline mercury levels in soils in Flanders. In a previous study, mercury contents in soils in Oost-Vlaanderen were found to be significantly above levels reported elsewhere. For the current study, observations were extended over two more provinces, West-Vlaanderen and Antwerpen. Ranges of soil Hg contents were distinctly higher in the province Oost-Vlaanderen (interquartile range from 0.09 to 0.43mg/kg) than in the other provinces (interquartile ranges from 0.7 to 0.13 and 0.7 to 0.15mg/kg for West-Vlaanderen and Antwerpen, respectively). The standard threshold method was applied to separate soils containing baseline levels of Hg from the data. Baseline concentrations for Hg were characterised by a median of 0.10mg Hg/kg dry soil, an interquartile range from 0.07 to 0.14mg/kg and a 90% percentile value of 0.30mg/kg. The influence of soil properties such as clay and organic carbon contents, and pH on baseline Hg concentrations was not important. Maps of the spatial distribution of Hg levels showed that the province Oost-Vlaanderen exhibited zones with systematically higher Hg soil contents. This may be related to the former presence of many small-scale industries employing mercury in that region. [Copyright &y& Elsevier]

Abstract: Background concentration values of trace elements were determined for soils in the southern part of the Grand Duchy of Luxembourg, which are developed on the Bituminous shale (BS), the so-called “Bifrons” shale, and the “Minette” (M) Fe-oolitic sandstone substrates. Sampling sites with minimal anthropogenic influence were selected, and soil profile samples were analysed for major and trace element contents. A clear distinction is seen between the trace element content of the soils developed on the Minette sandstone on the one hand and those developed on shales on the other hand. For the Minette soil samples, most elements are present in concentrations exceeding those reported in literature for soils developed upon sandstones, with, for example, values of up to 278 mg kg−1 As (median value 123 mg kg−1), 287 mg kg−1 Cr (median value 126 mg kg−1), and 95 mg kg−1 Co (median value 33 mg kg−1). In the shale soil samples, concentrations are generally lower except for Cu and Mo. These elements reach maxima of up to 66 mg kg−1 Cu (median value 41 mg kg−1) and 59 mg kg−1 Mo (median value 26 mg kg−1). The results confirm the importance of determining background concentrations locally. Bivariate analysis shows a linear relationship between Fe content and elements such as As, Co, and Ni for the Minette soils. No relationship is found between trace element concentrations and clay or organic carbon (OC) content, but this could be due to the limited variation of these factors among the studied soils. A reconnaissance study with regard to the availability of the trace elements in the Minette soil samples shows that these elements are quite immobile and hence of minimal threat to the ecosystem. [Copyright &y& Elsevier]

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Copyright of Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The concentrations of Cd, Co, Cu, Ni, Pb and Zn were determined in the Antarctic copepods Rhincalanus gigas (Brady, 1883), Calanus propinquus (Brady, 1883), Calanoides acutus (Giesbrecht, 1902), Metridia curticauda (Giesbrecht, 1889) and Metridia gerlachei (Giesbrecht, 1902). Samples were taken at seven different stations between 18.01.1999 and 19.02.1999. Metal concentrations in biological tissue were determined by graphite furnace atomic absorption spectroscopy (GFAAS) with Zeeman background correction and by flame AAS (air–acetylene) with deuterium background correction. We found high mean Cd concentrations in the Metridia species of about 10 μg Cd g−1 and 3–6 μg Cd g−1 in the other copepods. Co and Pb concentrations were low in all species investigated (<0.1 μg Co g−1 and <1 μg Pb g−1). Zn concentrations were high in M. gerlachei and R. gigas (518 and 430 μg Zn g−1). In comparison to copepods from Arctic Seas (Fram Strait, Greenland Sea) and the North Sea, Cd and Cu concentrations appear higher in Antarctic copepods, while Ni and Pb concentrations are similar in both polar regions and Pb concentrations are higher in the North Sea. Variability between species and different regions are discussed. [Copyright &y& Elsevier]