The influence of a city on element contents of a terrestrial moss (Hylocomium splendens)

Forty terrestrial moss (Hylocomium splendens) samples were collected along a 120-km-long south-north transect running through Norway's largest city Oslo. Concentrations of 29 chemical elements (Ag, Al, Au, Ba, Bi, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, La, Mg, Mn, Mo, Na, Ni, P, Pb, Pt, S, Sb, Sr, Th, Ti, and Zn) and values for loss on ignition (475 degrees C) are reported. Silver (Ag), Al, Au, Bi, Cd, Co, Cr, Cu, Fe, Mo, Ni, Pb, Pt, Sb, Th, Ti, and Zn all show a characteristic Oslo peak when element concentrations are plotted against location of the sample site along the transect. Gold (Au) and Pt show the greatest relative enrichment of all elements in the city (ca. 10x "background"). Titanium (Ti), which is related to local minerogenic dust rather than anthropogenic emissions, shows a significant peak in Oslo. Loss on ignition, a measure of the amount of organic material in a sample, shows a negative peak in Oslo and at sites close to a known dust source. Input of fine dust thus appears to dominate many of the observed element concentrations in moss. The concentrations of Na are clearly influenced by the input of marine aerosols and show decreasing concentrations from south (near Oslo Fjord) to north (inland). The major plant nutrients Ca, K, Mg, P and S, as well as Hg, are the few elements displaying no spatial dependency along the transect. Element concentrations reach background variation levels at a distance of 20-40 km from the city centre.     

Variations in heavy metal concentrations in the moss species Abietinella abietina (Hedw.) Fleisch. according to sampling time,within site variability and increase in biomass

Concentrations of Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mo, Ni, Pb, V and Zn were analysed in the moss Abietinella abietina (Hedw.) Fleisch. to estimate atmospheric heavy metal depositions. Samples were taken at five comparable sites within a radius of 25 m four times during the year 2000 (July 3rd, August 3rd, September 7th, October 3rd). The samples were taken by means of a PVC-tube (r=10 cm) and could therefore be related to aboveground growth and aerial deposition. The investigation showed significant differences between the various sampling times for concentrations of all heavy metals in total but not between concentrations of a single metal. For Cu, Hg, Mo, Pb and Zn temporal variation (=variation between the four times of sampling) was larger than spatial variation (=variation of concentrations between sub-samples at a single sampling time). Growth rates of the mosses differed significantly between sampling times, which reflects the low precipitation at the beginning of the season. Biomass increase, dust and precipitation influenced the metal concentrations. The calculation of deposition rates, which takes growth rates into account, showed significant differences between the various sampling times for Al, Cd, Cr, Cu and Ni, which is controversial to the results obtained from concentrations of these elements. Additionally, the calculation of atmospheric deposition rates showed a constant increase of metal depositions throughout the investigated period, which can not be seen by considering the concentrations only.     

An extended study of heavy metal deposition in Galicia (NW Spain) based on moss analysis

This paper describes the first attempt to determine the levels of heavy metal contamination in Galicia (NW Spain) by analysis of moss species. Samples of Scleropodium purum and Hypnum cupressiforme were collected from 75 sites, in 1995 and 1997, and analysed by atomic absorption spectrophotometry and atomic fluorescence for Al, As, Co, Cr, Cu, Fe, Hg, Ni, Pb and Zn. Comparisons were made between the two moss species used and, for those elements present at different concentrations in the two species, regression lines were made for interspecies calibration. Distribution maps were drawn up for each of the elements according to their concentration in the moss. In certain areas it was possible to relate deposition to the existence of known sources of contamination. The study demonstrates that the highest levels of elements were found in the most heavily industrialised and populated areas. Concentrations of As, Cu, Hg and Ni, recorded during the 1997 sampling were significantly higher than those found in 1995, possibly due to agricultural and industrial activities.     

Concentration and fate of trace metals in Mekong River delta

In the Mekong River delta and its associated coastal zone trace elements concentrations (Cd, Cu, Ni and Pb) were measured in the dissolved phase (DP) during dry (March 1997) and wet (October 1997) seasons. As, Co, Cr, Ni, Pb, and Al were also measured in suspended matter (SM) and total and organic carbon, trace elements (Cd, Cr, Cu, Hg, Mn, Ni, Pb, Zn) and macro elements in superficial sediments (S). Trace metal concentrations in DP and SM during the contrasting hydrological conditions were generally found within the range observed for uncontaminated environment. The average DP concentrations (nM) in the river for March and October are: Cd 0.03 and 0.09, Cu 15 and 14, Ni 7.8 and 8.4, Pb 0.51 and 0.50, respectively. In general there is no significant difference between the concentrations observed during dry and wet season. The evolution of the DP trace metal concentration in the surface water within the salinity gradient suggests no noticeable exchange between the particulate and dissolved phase. This result is in good agreement with those observed in most plume structures studied so far. The average concentrations in the SM (microg/g) (March, October) at the river end-member are: As (24; 11), Co (17; 9), Cr (49; 29), Ni (32; 18), Pb (42; 19) and Al (113,000; 67,000), respectively. All trace elements show higher concentrations in March than in October, with an average increase of two times. This is essentially related to grain size effect since smaller particles were supplied during dry season. These differences are not reflected in the mixing zone, which integrates the seasonal variations. The concentration of major elements (C total, C organic, Si, Al, Ca, K, Fe, Mg, Ti), trace elements (Pb, Zn, Cu, Ni, Mn, Cr, Cd, Hg) in superficial sediments, show similar values during the two seasons and does not show any important variation with depth, indicating either a very fast sedimentation rate and/or the absence of any significant contamination.     

Lichen (Xanthoria parietina) biomonitoring of trace element contamination and air quality assessment in Pisa Province (Tuscany, Italy)

In the northern part of Pisa Province (Tuscany, Italy), the use of lichens as both airborne trace element biomonitors and air quality bioindicators is described. The following elements were analysed in Xanthoria parietina: As, Cd, Cr, Ni, Pb, V, Zn and Hg, and the results are compared with those we previously obtained in Livorno Province (Tuscany) using the same lichen species. The results identify spots of different environmental metal contamination and air quality. Median values of Pb, V and Ni concentrations were much lower than those of Livorno Province, with maximum values even nine times lower. Arsenic contamination was also lower, while Cd, Hg and Zn levels were similar in the two areas. In Pisa Province, the highest levels of contamination were recorded for Zn, Pb, Cr and Ni, and a degree of agreement was found between air quality and metal concentrations in lichens. The air quality in Pisa Province is better than in Livorno Province, even if the different climatic and orographic features of the two areas may influence the presence of lichen species and thus an assessment of air quality.     

The elemental composition and sources of house dust and street dust

The elemental compositions of house dust, street dust and soil have been determined for 26 elements on material collected in Christchurch, New Zealand. The elements Hf, Th, Sc, Sm, Ce, La, Mn, Na, K, V, Al and Fe may be considered to be soil-based and contribute about 45–50% to house dust and 87% to street dust. The elements which are enriched (>3 times) in the dusts relative to the levels found in local soils, are Br, Cu, Cl, Pb, Zn, Cr, Ca, Co, As and Sb in house dust, and Zn, Cr, Cu and Pb in street dust.     

Comparison of the element composition in several plant species and their substrate from a 1500000-km2 area in Northern Europe.

Leaves of 9 different plant species (terrestrial moss represented by: Hylocomium splendens and Pleurozium schreberi; and 7 species of vascular plants: blueberry, Vaccinium myrtillus; cowberry, Vaccinium titis-idaea; crowberry, Empetrum nigrum; birch, Betula pubescens; willow, Salix spp.; pine, Pinus sylvestris and spruce, Picea abies) have been collected from up to 9 catchments (size 14-50 km2) spread over a 1500000 km2 area in Northern Europe. Soil samples were taken of the O-horizon and of the C-horizon at each plant sample site. All samples were analysed for 38 elements (Ag, Al, As, B, Ba, Be, Bi, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Rb, S, Sb, Sc, Se, Si, Sn, Sr, Th, Tl, U, V, Y, Zn and Zr) by ICP-MS, ICP-AES or CV-AAS (for Hg-analysis) techniques. The concentrations of some elements vary significantly between different plants (e.g. Cd, V, Co, Pb, Ba and Y). Other elements show surprisingly similar levels in all plants (e.g. Rb, S, Cu, K, Ca, P and Mg). Each group of plants (moss, shrubs, deciduous and conifers) shows a common behaviour for some elements. Each plant accumulates or excludes some selected elements. Compared to the C-horizon, a number of elements (S, K, B, Ca, P and Mn) are clearly enriched in plants. Elements showing very low plant/C-horizon ratios (e.g. Zr, Th, U, Y, Fe, Li and Al) can be used as an indicator of minerogenic dust. The plant/O-horizon and O-horizon/C-horizon ratios show that some elements are accumulated in the O-horizon (e.g. Pb, Bi, As, Ag, Sb). Airborne organic material attached to the leaves can thus, result in high values of these elements without any pollution source.     

Biomonitoring of metal deposition in northern Spain by moss analysis

The results of the first survey carried out in northern Spain to determine atmospheric deposition of metals by analysis of terrestrial mosses, are described. Samples of different mosses, mainly Hypnum cupressiforme and Scleropodium purum, were collected from 134 sampling sites, between 1995 and 1996. Levels of Al, As, Cr, Cu, Fe, Hg, Ni, Pb and Zn, were determined by flame atomic absorption or atomic fluorescence spectrophotometry. Regression analysis was used to compare the capacity of the selected moss species to accumulate the elements, and intercalibration of accumulation in these species was carried out where necessary. Distribution maps were prepared to allow the zones most affected by metal deposition to be identified and to relate this to known sources of contamination: electricity power stations and other industries (e.g. Hg and Ni), edaphic contamination (e.g. Al and Cr) and road traffic (Pb). Background levels of metals in each species were also determined for the study area.     

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

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

Trophodynamics of mercury and other trace elements in a pelagic food chain from the Baltic Sea

Mercury (Hg) and 13 other trace elements (Al, Ti, V, Cr, Fe, Mn, Co, Ni, Cu, Zn, As, Cd, and Pb) were measured in phytoplankton, zooplankton, mysis and herring in order to examine the trophodynamics in a well-studied pelagic food chain in the Baltic Sea. The fractionation of nitrogen isotopes (δ¹⁵N) was used to evaluate food web structure and to estimate the extent of trophic biomagnification of the various trace elements. Trophic magnification factors (TMFs) for each trace element were determined from the slope of the regression between trace element concentrations and δ¹⁵N. Calculated TMFs showed fundamental differences in the trophodynamics of the trace elements in the pelagic food chain studied. Concentrations of Al, Fe, Ni, Zn, Pb and Cd showed statistically significant decreases (TMF < 1) with increasing trophic levels and thus these trace elements tropically dilute or biodilute in this Baltic food chain. Cu, As, Cr, Mn, V, Ti and Co showed no significant relationships with trophic levels. Hg was unique among the trace elements studied in demonstrating a statistically significant increase (TMF > 1) in concentration with trophic level i.e. Hg biomagnifies in this Baltic food chain. The estimated TMF for Hg in this food chain was comparable to TMFs observed elsewhere for diverse food chains and locations.     

Concentrations of heavy metals and plant nutrients in water, sediments and aquatic macrophytes of anthropogenic lakes (former open cut brown coal mines) differing in stage of acidification.

Concentration of heavy metals (Al, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr, V and Zn) as well as macronutrients (N, P, K, Ca, Mg, S) were measured in water, bottom sediments and plants from anthropogenic lakes in West Poland. The collected plants were: Phragmites australis, Potamogeton natans, Iris pseudoacorus, Juncus effusus, Drepanocladus aduncus, Juncus bulbosus, Phalaris arundinacea, Carex remota and Calamagrostis epigeios. Two reference lakes were sampled for Nymphaea alba, Phragmites australis, Schoenoplectus lacustris, Typha angustifolia and Polygonum hydropiper. These plants contained elevated levels of Cd, Co, Cr, Cu and Mn, and part of the plants contained in addition elevated levels of Mn, Fe, Pb, Ni and Zn. Analyses of water indicated pollution with sulfates, Cd, Co, Ni. Zn, Pb and Cu, and bottom sediments indicated that some of the examined lakes were polluted with Cd, Co and Cr. Strong positive correlations were found between concentrations of Co in water and in plants and between Zn in sediments and plants, indicating the potential of plants for pollution monitoring for this metal. Heavy metal accumulation seemed to be directly associated with the exclusion of Ca and Mg.     

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

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

Mineral content in legumes and nuts: contribution to the Spanish dietary intake

We evaluated the levels of essential elements as Cu, Cr, Fe and Zn, and toxic elements as Al, Ni, Pb and Cd in a total of 40 samples of different legumes and 56 samples of different nuts, that are widely consumed in Spain. These elements were determined in the samples mineralized with HNO(3) and V(2)O(5), using electrothermal atomic absorption spectrometry (ETAAS) as the analytical technique. Reliability of the procedure was checked by analysis of a certified reference material. No matrix effects were observed and aqueous standard solutions were used for calibration. In legumes, the levels ranged from 1.5-5.0 microg Cu/g, 0.05-0.60 microg Cr/g, 18.8-82.4 microg Fe/g, 32.6-70.2 microg Zn/g, 2.7-45.8 microg Al/g, 0.02-0.35 microg Ni/g, 0.32-0.70 microg Pb/g and not detectable-0.018 microg Cd/g. In nuts, the levels ranged from 4.0-25.6 microg Cu/g, 0.25-1.05 microg Cr/g, 7.3-75.6 microg Fe/g, 25.6-69.0 microg Zn/g, 1.2-20.1 microg Al/g, 0.10-0.64 microg Ni/g, 0.14-0.39 microg Pb/g, and not detectable-0.018 microg Cd/g. A direct statistical correlation between Cu-Cr, Zn-Al and Cr-Ni (P<0.05), and Al-Pb (P<0.001), has been found. The growing popularity of these products in recent years on the basis of its nutritional properties and beneficial effects, requires additional data and a periodical control. In addition, the present findings are of potential use to food composition tables.     

Active biomonitoring of element uptake with terrestrial mosses: a comparison of bulk and dry deposition

Moss (Scleropodium purum) transplants were used to study bioconcentration originating from dry and bulk deposition, by measuring the tissue contents of Al, As, Ca, Cu, Fe, Hg, Mn, Ni, Pb, Se and Zn. Furthermore, a laboratory experiment was carried out to determine the sequence of maximum concentration and affinity of Al, Cu, Fe, Hg, Ni, Pb and Zn, in S. purum. We found that in many of the transplants, for the same period of exposure, higher levels of metals were accumulated via dry deposition than via bulk deposition. This result may be explained by the simple washing action of the rain on the surface of the moss, and by the existence of processes that provoke the loss of some of the accumulated elements: intercationic displacement and leaching caused by acid precipitation. Modelling of the final bioconcentration observed, as a balance of inputs and outputs of elements, revealed that this terrestrial moss does not integrate, but rather concentrates atmospheric deposition, and there exists a state of unstable equilibrium between inputs and outputs of elements, a state that is determined by the characteristics of the surrounding environment. On the basis of the results obtained in this study, we can conclude that at present, it is not possible to extrapolate the calibrations between the concentrations of elements accumulated in a certain species of moss to values of atmospheric deposition (bulk deposition) from one place to another with different environmental conditions.     

Biomonitoring of nine elements by the lichen Xanthoria parietina in Adriatic Italy: a retrospective study over a 7-year time span

The results of long-term biomonitoring of nine elements (Cd, Cr, Ni, Pb, V, Cu, Zn, Fe and Al) with the epiphytic lichen Xanthoria parietina over a seven year time span are reported. A total of 51 sampling stations were monitored in two surveys, obtaining information about heavy metal concentrations in a large area characterized by a high impact of industrial and urban sources of air pollution. The results showed that the approach adopted is indeed a reliable tool to assess environmental alteration, pinpointing not only the trends of the nine elements analysed but also their reciprocal correlations. As a consequence it was possible to characterize changes in air pollution composition and the common origin and behavior of several groups of elements.     

Elemental chemistry of four lichen species from the Apostle Islands,Wisconsin, 1987, 1995 and 2001

Four lichen species sampled three times over a 15-year time span at four of the Apostle Islands, Wisconsin were analyzed for 16 chemical elements in order to determine time trends and spatial patterns. Factor analyses of the data revealed that elements associated with soils (Al, Cr, Fe, Na, Ni and S) have increased over the study period, while nutrient and pollutant elements (Cu, K, P, Pb and Zn) have decreased. Four other elements (Ca, Cd, Mg and Mn) were unchanged over time. Cladina rangiferina, a terricolous species, contained the lowest concentrations of all elements, while the corticolous species Evernia mesomorpha was highest in soil elements, Hypogymnia physodes was highest in Ca, Cd, Mg and Mn, and Parmelia sulcata was highest in the nutritional elements. Lichens on islands within 3-4 km of the mainland were highest in soil elements, which decreased with distance from the mainland. Elements that were 18-43% greater on the nearest islands were significantly different between near and far islands. Eight elements (Al, Ca, Cd, K, Mg, Mn, P and S) exceeded enrichment levels for Hypogymnia physodes, suggesting possible contamination problems for this species. Although Pb has decreased significantly over the time period, other elements have increased in the lichens while decreasing in the atmosphere, suggesting that accumulation in the environment is continuing.     

Influence of liming on metal sequestration in lake sediments over recent decades

Sediment profiles from five limed and six reference softwater lakes included in Swedish monitoring programmes were subjected to multi-element analysis to investigate the influence of lime treatment since 1977 on the sequestration of metals in lake sediments. We hypothesised that liming causes increased sedimentation of elements for which the mobility is primarily controlled by pH, e.g. Al, Cd, Co, Ni and Zn, whereas elements that are less influenced by pH fluctuations, e.g. Hg and Pb, are not affected by lime treatment. Further, we introduce a normalisation of metal concentrations with respect to Cu concentration in order to separate the effects of lime treatment from those related to temporal trends in airborne metal deposition or short-term variations in environmental conditions. This approach is shown to emphasise the effect of liming on the sediment accumulation of metals, thus separating it from other sources of variability. We found that liming causes increased sequestration of Al, As, Cd, Co, Fe, Mn, Ni and Zn, in the case of As and Co probably at least partly caused by an increased adsorption to Al, Fe and Mn oxyhydroxides. On the other hand, no influence of lime treatment could be demonstrated for Hg, Pb, Cr, V and P, despite an increase of pH by about two units.     

Investigation of absolute metal uptake efficiency from precipitation in moss

Bioaccumulation of metals in moss was studied by the absolute method using a specially designed 'moss bag' technique. Bulk deposition was collected in open areas along with bulk deposition collected under moss. An absolute uptake efficiency of approximately 60% was obtained, which is in good agreement with the value obtained by a relative method. The absolute uptake efficiency varied between 0 and 92%, hence uptake of metals depends very strongly on microenvironmental conditions which can even cause leaching of metals from moss. The best retained elements were Pb, Ni, Cu and V, while Cd, Cr, Fe and Zn exhibited significantly lower uptake efficiencies. Manganese in all cases showed leaching of the element from moss.     

Deposition of airborne elements from Sembule steel mill surveyed by moss analysis

The local contamination of airborne elements caused by the Sembule steel works was studied by the analysis of Mg, Ca, Fe, Ni, Pb and Cd accumulated in transplanted moss. The concentrations of heavy metals (Fe, Ni, Pb, Cd) and other elements (Mg, Ca) were determined in soil, moss and water collected in the vicinity of Sembule steel mill. Comparison of elemental ratios indicate that there is contamination by heavy metals around this area. Accumulation coefficients have been applied to moss, soil and water data in an attempt to work out the contribution of these elements to water via soil and air. In evaluating Fe, Ni, Pb and Cd contents of river water and soil, a distinction was made between the amounts which are taken up from soil and those reaching the water as air depositions (as measured by use of moss). The calculations indicate that soil contributes 79.4, 96.3, 23.3, 0.50, 14.6 and 30.6 percent of Mg, Ca, Cd, Pb, Ni and Fe, respectively, whereas air deposition contributes 20.6, 3.73, 76.7, 99.5, 85.4 and 69.4 percent, respectively.     

Magnetic properties of terrestrial moss (Hylocomium splendens) along a north-south profile crossing the city of Oslo, Norway

Magnetic measurements are routinely used in geophysics and environmental sciences to obtain detailed information about concentrations and quality of iron minerals. Here, magnetic properties of 38 terrestrial moss samples (Hylocomium splendens) from a ~ 120 km south-north transect through Oslo are studied to gain better insight into the nature and origin of their Fe fraction. The concentration-dependent quantities, magnetic susceptibility k, and isothermal remanent magnetization IRM(700mT) after weight normalization have significantly higher values in urban regions, and parallel the previously found concentration signals of 16 out of 29 chemical elements (Ag, Al, Au, Bi, Cd, Co, Cr, Cu, Fe, Mo, Ni, Pb, Pt, Sb, Ti, and Zn). Because there is no evidence that Hylocomium splendens produces biogenic magnetic remanence carriers, the increase in IRM is attributed to adsorption of dust containing iron oxide minerals. This agrees with previous observations that Ti concentrations, related to local mineral dust, have a peak in Oslo, and at sites close to known dust sources. Scanning electron microscopy images also showed an increased density of minerogenic particles on the moss surfaces in the urban samples, which qualitatively supports the dust based interpretation. The concentration-independent ratios k/Fe and IRM(700mT)/Fe also have extreme values in the urban parts of the transect. This indicates that more of the total iron occurs in magnetically ordered form and in remanence carriers, interpreted as adsorbed dust. In addition, purely magnetic ratios displayed differences in urban and rural areas, indicating that their magnetic dust particles are inherently of different types. Therefore, it is likely that anthropogenic dust sources contribute considerably to the magnetic signal. Urban dust enhancement is not exclusively due to increased erosion, leading to higher loads of geogenic dust in the atmosphere, but also to specific anthropogenic sources from combustion, corrosion, or other synthetic emitters.