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[en] This paper evaluates approaches to calculate acceptable loads for metal deposition to forest ecosystems, distinguishing between critical loads, stand-still loads and target loads. We also evaluated the influence of including the biochemical metal cycle on the calculated loads. Differences are illustrated by examples of Cd, Cu, Pb and Zn for a deciduous forest on five major soil types in the Netherlands. Stand-still loads are generally lower than critical loads, which in turn are lower than the target loads indicating that present levels are below critical levels. Uncertainties in the calculated critical loads are mainly determined by the uncertainty in the critical limits and the chemical speciation model. Including the metal cycle has a small effect on the calculated critical loads. Results are discussed in view of the applicability of the critical load concept for metals in future protocols on the reduction in metal emissions. - Critical load methods for metals can be used to assess future risks due to metal inputs.
[en] Air pollution by particulate matter is well linked with anthropogenic activities; the global economic crisis that broke out in the last year may be a proper indicator of this close relationship. Some economic indicators show the regional effects of the crisis on the Cantabria Region. The present work aims to evaluate the impact of the economic crisis on PM10 levels and composition at the major city of the region, Santander. Some metals linked to anthropogenic activities were measured at Santander and studied by Positive Matrix Factorization; this statistical analysis allowed to identify three main factors: urban background, industrial and molybdenum-related factor. The main results show that the temporal trend of the levels of the industrial tracers found in the present study are well agree with the evolution of the studied economic indicators; nevertheless, the urban background tracers and PM10 concentration levels are not well correlated with the studied economic indicators. - Highlights: → The impact of the crisis is higher on the PM-bound metal levels than on the PM levels. → The crisis effects on the trace metal associated to the urban background are negligible. → The temporal trend of the industrial trace metals levels and the studied economic indicators is similar. → The crisis effects on the main industrial tracer levels in PM2.5 and PM10 are similar. - The study presents an evaluation of the economic crisis impact on PM levels and composition at a coastal urban area in the Region of Cantabria (Northern Spain).
[en] The response of specific groups of organisms, like Collembola to atmospheric nitrogen (N) deposition is still scarcely known. We investigated the Collembola community in a subalpine forest (Alptal, Switzerland) as subjected for 12 years to an experimentally increased N deposition (+25 on top of ambient 12 kg N ha-1 year-1). In the 0-5 cm soil layer, there was a tendency of total Collembola densities to be lower in N-treated than in control plots. The density of Isotomiella minor, the most abundant species, was significantly reduced by the N addition. A tendency of lower Collembola group richness was observed in N-treated plots. The Density-Group index (dDG) showed a significant reduction of community diversity, but the Shannon-Wiener index (H') was not significantly affected by the N addition. The Collembola community can be considered as a bioindicator of N inputs exceeding the biological needs, namely, soil N saturation. - Collembola community, which was significantly affected by a long-term N addition experiment, can be considered as a bioindicator of N saturation.
[en] The aim of this study is to assess the relevance and the potential of Posidonia oceanica as a tracer of past mercury contamination. Shoots were collected on two sites, an impacted site, Rosignano (Tuscany, Italy), and a pristine site, Tonnara (Corsica, France). Lepidochronology was used to measure mercury concentrations in living sheaths and in the corresponding dead sheaths. The results show that there is an overestimation of mercury concentrations in dead sheaths (because of the degradation of this tissue due to its ageing), overestimation which stabilizes itself from the third lepidochronological year onwards (trend significant only for Rosignano). Thus, it is possible to estimate previous mercury concentrations and to date a contamination, by measuring mercury concentration in the dead sheaths of a given lepidochronological year and by taking into account the degradation of the sheaths. Therefore, Posidonia oceanica can be used to reconstruct the evolution of the past mercury contamination. - Posidonia oceanica sheaths allow to reconstruct the evolution of the past mercury contamination
[en] To determine background values of the 252 chemical compounds listed in Dutch legislation, a survey was designed with the aim of estimating percentiles of the cumulative frequency distributions and areal fractions exceeding the former, legislative reference values. Sampling locations were selected by probability sampling, so that in estimating the target quantities no model assumptions on the spatial variation were required, and valid estimates could be obtained by design-based inference. Strata in random sampling were formed by overlaying an aggregated soil map and land use map. For most of the heavy metals the areal fraction with concentrations in the topsoil (0-10 cm) exceeding the reference value was smaller than the allowable maximum of 5%. For these compounds a background value was determined smaller than the reference value. Exceptions were V, Co, Ba and Cu, for which a background value was defined (slightly) larger than the reference value. - Legislative background values can be best derived by probability sampling and design-based estimation.
[en] Introduction: Exposure to particulate matter with diameter ≤10 μm (PM10) entails well documented adverse effects on human health. In the last decade, concentration of PM10 in Lombardy (10 million inhabitants), Italy, has been gradually decreasing. We evaluated how the mortality burden due to PM10 varied in that same period. Methods: We focused on 13 areas of the Region in 2003–2014: 11 cities with more than 50,000 inhabitants, 1 smaller alpine town and 1 agricultural province. For each area, we collected PM10 annual average concentrations and natural mortality data, and we used the posterior area-specific effects from a previous Bayesian meta-analysis to estimate the short-term impact of PM10 on mortality, in terms of deaths attributable (AD) to annual average exposures exceeding the WHO threshold of 20 μg/m3. Results: PM10 annual average values showed a non-homogenous decreasing trend in the investigated time period in most of the areas. Overall, the population-weighted exposure levels decreased, except for a peak in 2011, but never met the WHO threshold. In 2003–2006, PM10 levels were responsible, on average, for 343.0 annual AD from natural causes that decreased to 253.5 in 2007–2010 and to 208.3 in 2011–2014. Overall we estimated that PM10 was responsible for about 1% of all natural deaths (min-max range: 0.86%–1.42%); the impact was heterogeneous among areas. Conclusions: By collecting routinely available data for the most populated areas in Lombardy, we returned a picture of air pollution and health trends in the last decade. Notwithstanding the observed reduction in PM10 between 2003 and 2014 and the resulting decline in the number of AD, the impact is still relevant. Hence, appropriate policies for emission reduction could have a further beneficial effect on population health. Studies based on routine data and local effect estimates are recommended to properly inform the policy-making process. - Highlights: • PM10 concentrations in Lombardy, Italy have gradually decreased in the last decade. • We quantified PM10 impact on mortality as number of attributable deaths (AD). • Estimated annual AD were 343 in 2003–2006, 254 in 2007–2010, 208 in 2011–2014. • The reduction in PM10 paralleled the number of AD in 2003–2014. • Studies based on routine data can properly inform the policy-making process. - Using routine data and local effect estimates, we present trends of PM10 and its impact on mortality in 2003–2014 in Lombardy, Italy, providing evidence to inform the policy-making process.
[en] The Sao Domingos mine (Portugal) is, potentially, a good site for ecotoxicological studies, due to a pH and metal gradient of acid mine drainage. In this study, the toxicity of several mine sediments was evaluated using the aquatic oligochaete Lumbriculus variegatus as a test organism. Our hypothesis was that exposure to contaminated sediments would cause behavioural early warning responses in L. variegatus. Five sites, with pH ranging from 2.5 to 6.5, and with associated metals, were investigated. The results showed poor sediment quality in most of the collected sediments and Fe, S and As were the dominant elements in the samples. High mortalities were observed, ranging from 32.6 to 100%, indicating severe contamination. The collected sediments did not support good L. variegatus growth and significantly changed its behaviour. Early warning responses consisted of decreased locomotion and decreased peristaltic movements. A behaviour inhibition will affect the ecosystem balance by limiting the organisms' ability to avoid capture, which leads to a higher risk of predation. - Behavioural responses of the aquatic oligochaeta Lumbriculus variegatus may be used to detect early warning responses.
[en] Site-specific or soil type-specific ambient background concentrations (ABCs) of trace metals in soils are needed for risk assessment. We investigated three different methods for estimating ABCs in soils using a dataset of 5691 soil samples from England and Wales. The concentrations of Co, Cr and Ni were strongly associated with Al and Fe, and multiple regressions explained 62-85% of their variation, and Al and Fe can therefore be used to predict ABCs for these metals. Soil texture had a major influence on the concentrations of Cd, Co, Cr, Cu, Ni and Zn, and the medians were 3-5 fold higher in clayey than in sandy soils. This was used to predict texture-specific ABCs. Lead concentration was higher in acidic peaty soils than in other soils. A probability graph method was used to estimate ABC for Pb in a population of relatively uncontaminated soils. Potential applications of ABCs are discussed. - Ambient background concentrations of Cd, Co, Cr, Cu, Ni, Pb and Zn in surface soils are estimated using the soil inventory data for England and Wales
[en] Sixty moss samples were taken along transects of nine roads in Austria. The concentrations of 17 elements in four moss species were determined. There was a high correlation between several elements like Cu/Sb (0.906), Ni/Co (0.897) or Cr/V (0.898), indicating a common traffic-related source. Enrichment factors were calculated, showing highest enrichment levels for: Cr, Mo, Sb, Zn, As, Fe, V, Cu, Ni, and Co. For these elements, road traffic has to be assumed as a source, which is confirmed by a significant negative correlation of the concentrations in mosses to the distance from the road for most of these metals. The rate of decrease followed a log-shaped curve at most of the investigated transects, although the decline cannot be explained by a single model. Multiple regression analysis highlighted traffic density, distance from and elevation of the road as the most influencing factors for the deposition of the investigated elements. Heavy duty vehicles (HDVs) and light duty vehicles (LDVs) showed different patterns. A comparison of sites likely to be influenced by traffic emissions with average values for the respective regions showed no significant differences for road distances of more than 250 m. Nevertheless, at heavily frequented roads, raised deposition of some elements was found even at a distance of 1000 m. - Cr, Mo, Sb, Zn, As, Fe, V, Cu, Ni, and Co were identified as road traffic emissions and were mainly deposited within a distance of 250 m from major roads
[en] Fragments of antifouling paint and environmental geosolids have been sampled from the island of Malta and analysed for total and bioaccessible metals. Total concentrations of Ba, Cd, Cu, Pb, Sn and Zn were two to three orders of magnitude higher in spent antifouling composites relative to respective values in background soils and road dusts. Paint fragments were visible in geosolids taken from the immediate vicinity of boat maintenance facilities and mass balance calculations, based on Ba as a paint tracer, suggested that the most contaminated soils, road dusts and boatyard dusts contained about 1%, 7% and 9%, respectively, of antifouling particles. Human bioaccessibilities of metals were evaluated in selected samples using a physiologically based extraction technique. Accessibilities of Cd, Cu, Pb and Zn in the most contaminated solids were sufficient to be cause for concern for individuals working in the boat repair industry and to the wider, local community. - Geosolids near boat maintenance facilities are contaminated by antifouling paint particles containing high concentrations of bioaccessible metals.