Anthropogenic impacts in North Poland over the last 1300 years--a record of Pb, Zn, Cu, Ni and S in an ombrotrophic peat bog

Eutrophication and contamination dynamics of Schweriner See, NE-Germany, during the past 670 years - A multi-proxy approach on lacustrine surface sediments and sediment cores

A multi-proxy study on sedimentary records from Schweriner See (See = lake), NE-Germany, covering the past 670 years (from 1350 CE to today) combined with sediment surface samples to better understand lake internal dynamics enables to reconstruct local and supra-regional eutrophication and contamination trends. Our approach shows that a thorough understanding of depositional processes is crucial for core site selection since at Schweriner See wave- and wind-induced processes in shallow water areas (e.g. reworking) or carbonate precipitation resulting from groundwater inflow may have altered the desired (in this case anthropogenic) signal. In Schweriner See both eutrophication and contamination have been directly influenced by sewage and population dynamics of the city of Schwerin and its surroundings. A higher population density resulted in increased sewage volume, which was discharged directly into Schweriner See since 1893 CE. Maximum eutrophication was reached in the 1970s but a solid improvement in water quality only occurred after the German reunification (1990) as a combined result of a decrease in population density and the connection of all households to a new sewage treatment plant, which stopped the discharge of sewage waters into Schweriner See. These counter measurements were traced within the sediment records. Eutrophication and contamination trends were detected within the lake basin as shown by remarkable similarities in signals between several sediment cores. To get an understanding of regional contamination tendencies east of the former inner German border in the recent past we compared our results with sediment records from the southern Baltic Sea area, which show similar contamination trends.

Spatial and temporal trends in δ66Zn and 206Pb/207Pb isotope ratios along a rural transect downwind from the Upper Silesian industrial area: Role of legacy vs. present-day pollution

Transect sampling is an under-exploited tool in isotope studies of atmospheric pollution. Few studies have combined Zn and Pb isotope ratios to investigate whether atmospheric pollution at a receptor site is dominated by a different anthropogenic source of each of these toxic elements. It has been also unclear whether pollution abatement strategies in Central Europe have already resulted in regionally well-mixed background isotope signature of atmospheric Zn and Pb. Zinc and lead isotope ratios were determined in snow collected along a rural transect downwind from the Upper Silesian industrial area (southern Poland). Spatial and temporal gradients in δ⁶⁶Zn and ²⁰⁶Pb/²⁰⁷Pb ratios at four sites were compared with those of ore and coal collected in eight Czech and Polish mining districts situated at distances of up to 500 km. Snow pollution was extremely high 8 km from Olkusz in 2011 (1670 μg Zn L^-1; 240 μg Pb L^-1), sharply decreased between 2011 and 2018, and remained low in 2019-2021. Snow pollution was lower at sites situated 28-68 km from Olkusz. Across study sites, mean δ⁶⁶Zn and ²⁰⁶Pb/²⁰⁷Pb ratios of snow were -0.13‰ and 1.155, respectively. With an increasing distance from Olkusz, the δ⁶⁶Zn values first increased and then decreased, while the ²⁰⁶Pb/²⁰⁷Pb ratios first decreased and then increased. The δ⁶⁶Zn values in snow plotted closer to those of Upper Silesian ores (-0.20‰) than to the δ⁶⁶Zn values of Upper Silesian stone coal (0.52‰), showing predominance of smelter-derived over power-plant derived Zn pollution. The ²⁰⁶Pb/²⁰⁷Pb ratios of Upper Silesian coal (1.171) and Upper Silesian ores (1.180) were higher compared to those of snow. A²⁰⁶Pb/²⁰⁷Pb vs.²⁰⁸Pb/²⁰⁷Pb plot identified legacy pollution from leaded gasoline as the low-radiogenic mixing end-member. Across the transect sites, only the last sampling campaign exhibited a high degree of isotope homogenization for both Zn and Pb.

The multi-isotope biogeochemistry (S, C, N and Pb) of Hypogymnia physodes lichens: air quality approach in the Świętokrzyski National Park, Poland

The isotope biogeochemistry of bioindicators has widely demonstrated its added value in environmental issues by allowing to precisely identify sources of contamination. Most of the studies are based on studying one or two isotope systematics. Here, we are presenting an innovative multi-proxy approach that combines chemistry with both stable (C, S, N) and radiogenic (Pb) isotope systematics. Using Hypogymnia physodes bioindicators, we evaluated air quality in the complex environment of the Świętokrzyski National Park (ŚNP, Poland) with the ultimate objective of isotopically identifying the sources responsible for the observed contamination. Combining the isotope systematics showed that home heating is a major source of contamination in winter, whereas the contribution of road traffic increases during the summer. Pb isotope ratios identified industrial activities as the major source of this metal in the atmosphere.

Effect of peat organic matter on sulfide weathering and thallium reactivity: Implications for organic environments

Weathering of Tl-containing sulfides in a model (12-week) peat pot trial was studied to better understand their geochemical stability, dissolution kinetics, alteration products and the associated release and mobility of anthropogenic Tl in organic environments. We also present the effect of industrial acid rainwater on sulfide degradation and Tl migration in naturally acidic peat. Sphalerite (ZnS) was much less stable in peat than other Tl-containing sulfides (galena and pyrite), and thus acted as a major phase responsible for Tl mobilization. Furthermore, Tl incongruently leached out over Zn from ZnS, and accumulated considerably more in the peat solutions (≤5 μg Tl/L) and the peat samples (≤0.4 mg Tl/kg) that were subjected to acid rain watering compared to a deionized H₂O regime. This finding was in good agreement with the absence of secondary Tl-containing phases, which could potentially control the Tl flux into the peat. The behavior of Tl was not as conservative as Pb throughout the trial, since a higher peat mobility and migration potential of Tl was observed compared to Pb. In conclusion, industrial acid precipitations can significantly affect the stability of ZnS even in acidic peat/organic environments, making it susceptible to enhanced weathering and Tl release in the long term.

Thallium and lead variations in a contaminated peatland: A combined isotopic study from a mining/smelting area

Vertical profiles of Tl, Pb and Zn concentrations and Tl and Pb isotopic ratios in a contaminated peatland/fen (Wolbrom, Poland) were studied to address questions regarding (i) potential long-term immobility of Tl in a peat profile, and (ii) a possible link in Tl isotopic signatures between a Tl source and a peat sample. Both prerequisites are required for using peatlands as archives of atmospheric Tl deposition and Tl isotopic ratios as a source proxy. We demonstrate that Tl is an immobile element in peat with a conservative pattern synonymous to that of Pb, and in contrast to Zn. However, the peat Tl record was more affected by geogenic source(s), as inferred from the calculated element enrichments. The finding further implies that Tl was largely absent from the pre-industrial emissions (>~250 years BP). The measured variations in Tl isotopic ratios in respective peat samples suggest a consistency with anthropogenic Tl (ε²⁰⁵Tl between ~ -3 and -4), as well as with background Tl isotopic values in the study area (ε²⁰⁵Tl between ~0 and -1), in line with detected ²⁰⁶Pb/²⁰⁷Pb ratios (1.16-1.19). Therefore, we propose that peatlands can be used for monitoring trends in Tl deposition and that Tl isotopic ratios can serve to distinguish its origin(s). However, given that the studied fen has a particularly complicated geochemistry (attributed to significant environmental changes in its history), it seems that ombrotrophic peatlands could be better suited for this type of Tl research.

Temporal Archive of Atmospheric Microplastic Deposition Presented in Ombrotrophic Peat

Ombrotrophic peatland-fed solely from atmospheric deposition of nutrients and precipitation-provide unique archives of atmospheric pollution and have been used to illustrate trends and changes in atmospheric trace element composition from the recent decadal to the Holocene period. With the acknowledgment of atmosphere plastic pollution, analysis of ombrotrophic peat presents an opportunity to characterize the historical atmospheric microplastic pollution prevalence. Ombrotrophic peatland is often located in comparatively pristine mountainous and boreal areas, acting as sentinels of environmental change. In this paired site study, a Sphagnum ombrotrophic peat record is used for the first time to identify the trend of atmospheric microplastic pollution. This high altitude, remote location ombrotrophic peat archive pilot study identifies microplastic presence in the atmospheric pollution record, increasing from <5(±1) particles/m²/day in the 1960s to 178(±72) particles/m²/day in 2015-2020 in a trend similar to the European plastic production and waste management. Compared to this catchment's lake sediment archive, the ombrotrophic peat core appears to be effective in collecting and representing atmospheric microplastic deposition in this remote catchment, collecting microplastic particles that are predominantly ≤20 μm. This study suggests that peat records may be a useful tool in assessing the past quantities and trends of atmospheric microplastic.

Comment on: "A novel approach to peatlands as archives of total cumulative spatial pollution loads from atmospheric deposition of airborne elements complementary to EMEP data: Priority pollutants (Pb, Cd, Hg)" by Ewa Miszczak, Sebastian Stefaniak, Adam Michczyński, Eiliv Steinnes and Irena Twardowska

A recent paper by Miszczak et al. (2020) examines metal contamination of mires in Poland and Norway. The authors conclude that lead (Pb) records in ombrotrophic peatlands cannot be used to reconstruct the chronological history of anthropogenic activities due to post-depositional mobility of the metal. We contest this general conclusion which stands in contrast with a significant body of literature demonstrating that Pb is largely immobile in the vast majority of ombrotrophic peatlands. Our aim is to reaffirm the crucial contribution that peat records have made to our knowledge of atmospheric Pb contamination. In addition, we reiterate the necessity of following established protocols to produce reliable records of anthropogenic Pb contamination in environmental archives.

Reply to the comments on "A novel approach to peatlands as archives of total cumulative spatial pollution loads from atmospheric deposition of airborne elements complementary to EMEP data: Priority pollutants (Pb, Cd, Hg)" by V. De Vleeschouwer et al

In the comments by De Vleeschouwer et al. (2020) on a recent paper by Miszczak et al. (2020), two major issues were critically discussed: (1) the behavior of lead in ombrotrophic peatlands, with particular regard to the possible lead vertical mobility/immobility; (2) lead data use to accurately reconstruct historical contamination. The authors stated that "some of the conclusions reached by Miszczak et al. (2020) are based on misinterpretation or incorrect sampling and data analyses approaches". A reply to comments emphasises that these topics are not an issue of the paper. Its major idea was to use the unique natural systems (that are ombrotrophic peat bogs) as complete and reliable inventories for the assessment of cumulative loads of airborne element deposition independently upon its chronology. The results of a study conducted on ten ombrotrophic peat bogs in Norway and Poland showed a striking quantitative precision of such assessment. This has led to the idea of including ombrotrophic peat bogs into the EMEP network as tools for the completion of spatial distribution data on the fugitive element deposition. It would be helpful if a bigger number of experienced and widely recognized researchers take part in such project. Simultaneously, the analysis of source data, own results and case studies makes clear that the information regarding ombrotrophic peat properties is still insufficient to reconstruct precisely the chronology of metal contamination records, despite the development of high resolution sampling and analytical techniques and interpretational approaches. The clarification of some seemingly biased records would help to elucidate unexplained or unusual lead behavior in some outstanding cases. These cases demonstrate also that despite over 40 years of studies there are still the substantial gaps in our knowledge that need to be filled up.

A novel approach to peatlands as archives of total cumulative spatial pollution loads from atmospheric deposition of airborne elements complementary to EMEP data: priority pollutants (Pb, Cd, Hg)

A novel approach to using peatlands for assessment of cumulative contributions from long-range transport of pollutants (LRTP) - airborne trace elements - to spatial pollution was exemplified in evaluating retrospective atmospheric deposition of priority pollutants (Pb, Cd, Hg) in peat bogs in Norway in areas minor affected by local sources of pollution and in NW Poland located on the way of possible LRTP from Poland to Norway. Peat from the corresponding ¹⁴C-dated layers of five ombrotrophic bogs in each country, was analysed for trace element contents. Pollutant concentrations/load distribution along the peat profiles related to bulk density has given a clear evidence of uneven density-dependent temporal vertical migration of all studied elements that distorts the chronology of their deposition. Much higher loads of Pb, Cd and Hg in southern Norwegian bogs than in bogs located in NW Poland proved transboundary transport from neighbouring highly industrialized European countries to be much more significant contributor to high deposition of the priority pollutants in this area and rather excludes LRTP from Poland as a major source of total land pollution in southernmost Norway. The study showed excellent applicability of peat bogs for the exact assessment of retrospective cumulative pollutant loads from LRTP, but not for the identification of deposition chronology. Combining the use of ombrotrophic peat bogs as tools for retrospective monitoring of cumulative land pollution with airborne elements with current LRTP data within the Cooperative Programme for Monitoring and Evaluation of the Long-Range Transmission of Air Pollutants in Europe (EMEP) may provide a complete reliable picture of the effect of anthropogenic emissions on soil quality and create a foundation of optimum environmental policy and activities in this field.

Trace metals as markers for historical anthropogenic contamination: Evidence from the Peshawar Basin, Pakistan

Trace element concentrations in the youngest Holocene sedimentary archives, historical mining, and archaeological sites are reliable indicators for historical anthropogenic contamination. The Pleistocene-Holocene strata and the overlying archaeological sites of the Peshawar Basin, NW Pakistan provide sedimentary archives to explore historical anthropogenic controls on the distributions of trace elements. The basin with 2500 y of human civilization was sampled using archaeological trenches at Gor Khuttree and Hund, and six sections of youngest Pleistocene-Holocene strata along river banks. Geochemical analysis of high-resolution samples were conducted for both the lacustrine-floodplain sediments and archaeological sites. Results from various horizons of the archaeological sites provide signals for anthropogenic control on the distribution of As, Zn, Cu, Mo, Pb, Hg, Ag, and Au during the Meghalayan Stage of Holocene that gain progressive strength since the 18th century. The geochemical proxies negate direct mining of Cu-Pb and Zn in the area. The consistent, anthropogenic Ag and Au contribution to the system throughout the basin's archaeological history is a significant finding. When correlated against the anthropogenic mercury contamination, it appears that Hund was a major silver-gold panning site throughout its known history whereas Gor Khuttree was the major silver-gold processing center. The Peshawar Basin anthropogenic signals contribute to widespread European early Anthropocene signals at around 2000 BP related to the Greek and Roman mining. Signals during the Hindu Shahi period correlate well with the Medieval period mining and smelting peak signals observed in Europe and China. Hg, Ag, and Au concentrations in the area since the start of the 19th century CE correlates to the start of industrialisation. During the mid-20th century, these geochemical signals from the Gor Khuttree reflect anthropogenic contributions to the local system and correlate to the suggested base of a formalised Anthropocene.

Evidence for the onset of mining activities during the 13th century in Poland using lead isotopes from lake sediment cores

Efforts to study how human activities have influenced the environment since the end of the Roman period to present day are lacking for North Central Europe. Here, we present new lead (Pb) isotope data determined from two sediment cores collected from ancient lakes spanning the last 1500 years, located in the Kuyavian-Pomeranian Voivodeship, Poland. Study sites at Radzyń Chełmiński and Rywałd were used to differentiate Pb sources. Radzyń Chełmiński is located in the vicinity of a late Medieval Teutonic Order castle and town, while Rywałd is situated within a relatively pristine area until the 19th century when it became used for agricultural purpose. Core samples were analyzed for Pb concentration and isotopes (²⁰⁶Pb, ²⁰⁷Pb, ²⁰⁸Pb). Bayesian modeling was used to isolate the anthropogenic signal at each site over time. For both sites, Pb enrichment factors relative to titanium (Ti) and upper continental crust values range from 13 to 159. Lead isotopic ratios range from background, pre-anthropogenic local values (²⁰⁶Pb/²⁰⁷Pb = 1.31 ± 0.03‰, ²⁰⁸Pb/²⁰⁶Pb = 1.97 ± 0.04‰) to anthropogenic values (SW Poland coal, ore, slag ²⁰⁶Pb/²⁰⁷Pb = 1.17 ± 0.01‰, ²⁰⁸Pb/²⁰⁶Pb = 2.09 ± 0.01‰). Modeled anthropogenic contribution varies greatly over time, ranging from 14 to 100%. At Radzyń Chełmiński, modeled anthropogenic Pb contribution and measured Pb concentration follow similar trends. However, at Rywałd, from around A.D.1000 to 1400 CE these profiles diverge significantly. Our new insights highlight different sources of Pb from the 12th century to present day: (1) short range agricultural activities from the town, and (2) long range mining activities. Additionally, prior to the 12th century, our data suggest continental anthropogenic activity possibly favored by a warmer climate.

Historical trends of anthropogenic metals in sediments of Jiaozhou Bay over the last century

Reconstructing heavy metal historical trends are essential for better understanding anthropogenic impact on marine ecosystems. In this work, the ecological risk and sources of Cr, Mn, Ni, Cu, Zn, As, Cd, and Pb in Jiaozhou Bay were studied and the anthropogenic metal emissions was also quantified. The ecological risk was mainly caused by Cd, As and Cu, which presented an increasing trend with increased anthropogenic activities since the 1950s. The statistical analysis show that Cr, Mn, Ni, Cu and Zn were primarily from natural sources. Cadmium and Mn might originate from both natural and anthropogenic sources. Arsenic and Pb were sourced from agricultural activities and atmospheric precipitation, respectively. The anthropogenic flux of Cr, Mn, Ni, Cu, Zn, As, Cd and Pb were 138, 586, 63, 66, 161, 35, 0.31 and 44 mg/m²/a since the 1950s. Over 40.0% of Cu and As were quantified from anthropogenic emissions since the 1950s.

Atmospheric metal pollution records in the Kovářská Bog (Czech Republic) as an indicator of anthropogenic activities over the last three millennia

Three peat cores were extracted from the Kovářská Bog in the central Ore Mountains to study anthropogenic pollution generated by mining and metallurgy. The core profiles were ¹⁴C dated, and concentrations of selected elements were determined by ICP MS and HG-AAS. Principal component analysis indicated that Pb, Cu, As and Ag may be useful elements for the reconstruction of historical atmospheric pollution. Total and anthropogenic accumulation rates (ARs) of Pb, Cu and As estimated for the last ca. 3500years showed similar chronologies, and revealed twelve periods of elevated ARs of Pb, As and Cu related to possible mining and metallurgic activities. In total, four periods of elevated ARs of Pb, Cu and As were detected during the Middle and Late Bronze Ages, including a distinct Late Bronze Age pollution event between 1030BCE and 910BCE. The Iron Age included three episodes of increased ARs of Pb and As; the first and the most distinctive episode, recorded between 730 and 440BCE, was simultaneous with the Bylany culture during the Hallstatt Period. The Roman Age was characterized by one pollution event, two events were detected in the Middle Ages, and the last two during the modern period. Enhanced element ARs in the late 12th and 15th centuries clearly documented the onset of two periods of intense mining in the Ore Mountains. Metal ARs culminated in ca. 1600CE, and subsequently decreased after the beginning of the Thirty Years' War. The last boom of mining between 1700CE and 1830CE represented the last period of important metallurgical operations. Late Medieval and modern period metal ARs are in good agreement with written documents. Earlier pollution peaks suggest that local metal production could have a much longer tradition than commonly believed; however, archaeological or written evidence is scarce or lacking.

Recent atmospheric metal deposition in peatlands of northeast China: A review

China is one of the fastest-growing economies of the late 20th and early 21st centuries, and heavy metal emissions have increased in parallel with rapid industrialization and urbanization. Over the last decade, several studies of geochemical records from peat have reconstructed changes in atmospheric metal pollution in China. We review the peat records that detail the history of atmospheric metal pollution over the last two centuries in NE China. The ecological risk (ER) of accumulated metals and their potential eco-toxicological effects, through threshold and probable effect concentrations (TEC and PEC), are also evaluated. Peat records of metals show an increase of pollution loads in the environment over the pre-industrial level during the past two centuries, with an unprecedented increase in China over the last 60 years. There is generally good agreement between geochemical peat records from NE China and others records elsewhere in China. However, some discrepancies are observed especially with Hg records from lake sediments. These discrepancies could be explained by several factors, including post-depositional processes or uncertainties arising from dating methods. The ecological risk of heavy metals is found to be relatively weak in the remote and high-altitude environment in NE China. Although, most metals are under the TEC, Pb concentrations usually surpass it and are getting close to the PEC which indicates increasing ecological risks. Some areas of improvement have been highlighted such as the need for more long-term studies on atmospheric metals and a greater number of Pb isotopes records to better capture the long history of human activity and the spatial variability in metal deposition of the region.

Quantitative assessment of Pb sources in isotopic mixtures using a Bayesian mixing model

Lead (Pb) isotopes provide valuable insights into the origin of Pb within a sample, typically allowing for reliable fingerprinting of their source. This is useful for a variety of applications, from tracing sources of pollution-related Pb, to the origins of Pb in archaeological artefacts. However, current approaches investigate source proportions via graphical means, or simple mixing models. As such, an approach, which quantitatively assesses source proportions and fingerprints the signature of analysed Pb, especially for larger numbers of sources, would be valuable. Here we use an advanced Bayesian isotope mixing model for three such applications: tracing dust sources in pre-anthropogenic environmental samples, tracking changing ore exploitation during the Roman period, and identifying the source of Pb in a Roman-age mining artefact. These examples indicate this approach can understand changing Pb sources deposited during both pre-anthropogenic times, when natural cycling of Pb dominated, and the Roman period, one marked by significant anthropogenic pollution. Our archaeometric investigation indicates clear input of Pb from Romanian ores previously speculated, but not proven, to have been the Pb source. Our approach can be applied to a range of disciplines, providing a new method for robustly tracing sources of Pb observed within a variety of environments.

Anthropogenic- and natural sources of dust in peatland during the Anthropocene

As human impact have been increasing strongly over the last decades, it is crucial to distinguish human-induced dust sources from natural ones in order to define the boundary of a newly proposed epoch - the Anthropocene. Here, we track anthropogenic signatures and natural geochemical anomalies in the Mukhrino peatland, Western Siberia. Human activity was recorded there from cal AD 1958 (±6). Anthropogenic spheroidal aluminosilicates clearly identify the beginning of industrial development and are proposed as a new indicator of the Anthropocene. In cal AD 1963 (±5), greatly elevated dust deposition and an increase in REE serve to show that the geochemistry of elements in the peat can be evidence of nuclear weapon testing; such constituted an enormous force blowing soil dust into the atmosphere. Among the natural dust sources, minor signals of dryness and of the Tunguska cosmic body (TCB) impact were noted. The TCB impact was indirectly confirmed by an unusual occurrence of mullite in the peat.

Isotopic Composition of Pb in Peat and Porewaters from Three Contrasting Ombrotrophic Bogs in Finland: Evidence of Chemical Diagenesis in Response to Acidification

The isotopic composition of Pb was determined in Finnish peat bogs and their porewaters from Harjavalta (HAR, near a Cu-Ni smelter), Outokumpu (OUT, near a Cu-Ni mine), and Hietajärvi (HIJ, a background site). At HIJ and OUT, the porewaters yielded similar concentrations (0.1-0.7 μg/L) and isotopic composition ((206)Pb/(207)Pb = 1.154-1.164). In contrast, the peat profile from HAR yielded greater concentrations of Pb in the porewaters (average 2.4 μg/L), and the Pb is less radiogenic ((206)Pb/(207)Pb = 1.121-1.149). Acidification of the bog surface waters to pH 3.5 by SO2 emitted from smelting (compared to pH 4.0 at the control site) apparently promotes the dissolution of Pb-bearing aerosols, as well as desorption of metals from the surfaces of these particles and from the peat matrix. Despite this, the chronology of anthropogenic, atmospheric deposition for the past millenium recorded by the isotopic composition of Pb in all three peat bogs is remarkably similar. While the immobility of Pb in the peat cores may appear inconsistent with the elevated porewater Pb concentrations, Pb concentrations in the aqueous phase never amount to more than 0.01% of the total Pb at any given depth so that the potential for migration remains small. The low rates of vertical water movement in bogs generally combined with the size of the metal-containing particles in solution may be additional factors limiting Pb mobilization.

Peatland Microbial Communities as Indicators of the Extreme Atmospheric Dust Deposition

We investigated a peat profile from the Izery Mountains, located within the so-called Black Triangle, the border area of Poland, Czech Republic, and Germany. This peatland suffered from an extreme atmospheric pollution during the last 50 years, which created an exceptional natural experiment to examine the impact of pollution on peatland microbes. Testate amoebae (TA), Centropyxis aerophila and Phryganella acropodia, were distinguished as a proxy of atmospheric pollution caused by extensive brown coal combustion. We recorded a decline of mixotrophic TA and development of agglutinated taxa as a response for the extreme concentration of Al (30 g kg^-1) and Cu (96 mg kg^-1) as well as the extreme amount of fly ash particles determined by scanning electron microscopy (SEM) analysis, which were used by TA for shell construction. Titanium (5.9 %), aluminum (4.7 %), and chromium (4.2 %) significantly explained the highest percentage of the variance in TA data. Elements such as Al, Ti, Cr, Ni, and Cu were highly correlated (r > 0.7, p < 0.01) with pseudostome position/body size ratio and pseudostome position. Changes in the community structure, functional diversity, and mechanisms of shell construction were recognized as the indicators of dust pollution. We strengthen the importance of the TA as the bioindicators of the recent atmospheric pollution.

Anthropogenic lead concentrations and sources in Baltic Sea sediments based on lead isotopic composition

The Gulf of Gdańsk is influenced by heavy metals of anthropogenic origin. In this study, temporal concentration changes of Pb, Zn, Cd, and Cu were studied in six, 50 cm long sediment cores. The main aim of the study was to concentrate on the history of Pb fluxes and Pb isotopic composition ((206)Pb/(207)Pb and (208)Pb/(206)Pb) to trace Pb sources. The lowest Pb concentrations (19 μg g(-1)) were measured in sediments deposited circa 1860, while the highest Pb concentrations (63-147 μg g(-1)) were measured in sediments deposited between 1960s and 70s. Pre-industrial Pb fluxes were 7 Pb m(2)year(-1), while after WWII they reached 199 Pb m(2)year(-1). Highest (206)Pb/(207)Pb ratios (∼1.22) were measured in the oldest sediment layers, and the lowest (206)Pb/(207)Pb ratios (∼1.165) were measured in the sediments deposited in 1970s-90s. During the period of highest Pb contamination, the anthropogenic Pb fraction reached up to 93%. A general discussion of the Pb sources, emissions, and loads for Poland is included.

High-resolution reconstruction of atmospheric deposition of trace metals and metalloids since AD 1400 recorded by ombrotrophic peat cores in Hautes-Fagnes, Belgium

The objective of our study was to determine the trace metal accumulation rates in the Misten bog, Hautes-Fagnes, Belgium, and assess these in relation to established histories of atmospheric emissions from anthropogenic sources. To address these aims we analyzed trace metals and metalloids (Pb, Cu, Ni, As, Sb, Cr, Co, V, Cd and Zn), as well as Pb isotopes, using XRF, Q-ICP-MS and MC-ICP-MS, respectively in two 40-cm peat sections, spanning the last 600 yr. The temporal increase of metal fluxes from the inception of the Industrial Revolution to the present varies by a factor of 5-50, with peak values found between AD 1930 and 1990. A cluster analysis combined with Pb isotopic composition allows the identification of the main sources of Pb and by inference of the other metals, which indicates that coal consumption and metallurgical activities were the predominant sources of pollution during the last 600 years.

Isotopic identification of natural vs. anthropogenic lead sources in marine sediments from the inner Ría de Vigo (NW Spain)

San Simón Bay, the inner part of the Ría de Vigo (NW Spain), an area previously identified as highly polluted by Pb, was selected for the application of Pb stable isotope ratios as a fingerprinting tool in subtidal and intertidal sediment cores. Lead isotopic ratios were determined by inductively coupled plasma mass spectrometry on extracts from bulk samples after total acid digestion. Depth-wise profiles of (206)Pb/(207)Pb, (206)Pb/(204)Pb, (207)Pb/(204)Pb, (208)Pb/(204)Pb and (208)Pb/(207)Pb ratios showed, in general, an upward decrease for both intertidal and subtidal sediments as a consequence of the anthropogenic activities over the last century, or centuries. Waste channel samples from a nearby ceramic factory showed characteristic Pb stable isotope ratios different from those typical of coal and petrol. Natural isotope ratios from non-polluted samples were established for the study area, differentiating sediments from granitic or schist-gneiss sources. A binary mixing model employed on the polluted samples allowed estimating the anthropogenic inputs to the bay. These inputs represented between 25 and 98% of Pb inputs in intertidal samples, and 9-84% in subtidal samples, their contributions varying with time. Anthropogenic sources were apportioned according to a three-source model. Coal combustion-related emissions were the main anthropogenic source Pb to the bay (60-70%) before the establishment of the ceramic factory in the area (in the 1970s) which has since constituted the main source (95-100%), followed by petrol-related emissions. The Pb inputs history for the intertidal area was determined for the 20th century, and, for the subtidal area, the 19th and 20th centuries.

Lead contamination and source in Shanghai in the past century using dated sediment cores from urban park lakes

Lead contamination becomes of importance to urban resident health worldwide, especially for child health and growth. Undisturbed lake sediment cores are increasingly employed as a useful tool to backdate environmental contamination history. Five intact sediment cores collected from lakes in five urban parks were dated using (210)Pb and analyzed for total Pb content and isotope ratio to reconstruct the Pb contamination history over the last century in Shanghai, China. Total Pb content in the sediment cores increased by about 2- to 3-fold since 1900s. The profile of Pb flux in each sediment core revealed a remarkable increase of Pb contamination in Shanghai over the past century, especially in the latest three decades when China was experiencing a rapid economic and industrial development. Significant correlations were found between Pb fluxes in sediment cores and Pb emission from coal combustion in Shanghai. Coal combustion emission dominated anthropogenic Pb sources during the past century contributing from 52% to 69% of total Pb in cores, estimated by a three-end member model of Pb isotope ratios. Leaded gasoline emission generally contributed <30% of total Pb, which was banned by 1997 in the Shanghai region. Our results implicate that coal combustion-based energy consumption should be replaced, or at least partially replaced, to reduce health risks of Pb contamination in Shanghai.

Contrasting controls on arsenic and lead budgets for a degraded peatland catchment in Northern England

Atmospheric deposition of trace metals and metalloids from anthropogenic sources has led to the contamination of many European peatlands. To assess the fate and behaviour of previously deposited arsenic and lead, we constructed catchment-scale mass budgets for a degraded peatland in Northern England. Our results show a large net export of both lead and arsenic via runoff (282 ± 21.3 gPb ha(-1) y(-1) and 60.4 ± 10.5 gAs ha(-1) y(-1)), but contrasting controls on this release. Suspended particulates account for the majority of lead export, whereas the aqueous phase dominates arsenic export. Lead release is driven by geomorphological processes and is a primary effect of erosion. Arsenic release is driven by the formation of a redox-dynamic zone in the peat associated with water table drawdown, a secondary effect of gully erosion. Degradation of peatland environments by natural and anthropogenic processes has the potential to release the accumulated pool of legacy contaminants to surface waters.

Experimental evidence for mobility/immobility of metals in peat

The biogeochemical cycles of most toxic metals have been significantly altered by anthropogenic activities. Anaerobic, rain-fed organic soils are believed to record historical changes in atmospheric pollution. Suspected postdepositional mobility of trace elements, however, hinders the usefulness of peat bogs as pollution archives. To lower this uncertainty, we quantified the mobility of six trace metals in peat during an 18-month field manipulation. A replicated, reciprocal peat transplant experiment was conducted between a heavily polluted and a relatively unpolluted peatland, located 200 km apart in the Czech Republic (Central Europe). Both peatlands were Sphagnum-derived, lawn-dominated, and had water table close to the surface. A strikingly different behavior was observed for two groups of elements. Elements of group I, Fe and Mn, adjusted their abundances and vertical patterns to the host site, showing an extremely high degree of mobility. In contrast, elements of group II, Pb, Cu, Zn, and Ti, preserved their original vertical patterns at the host site, showing a high degree of immobility. Our experimental results suggest that not just lead, but also copper and zinc concentration profiles in peat are a reliable archive of temporal pollution changes within a wide pH range (2.5-5.8).

Atmospheric Pb and Ti accumulation rates from Sphagnum moss: dependence upon plant productivity

The accumulation rates of atmospheric Pb and Ti were obtained using the production rates of Sphagnum mosses collected in four ombrotrophic bogs from two regions of southern Germany: Upper Bavaria (Oberbayern, OB) and the Northern Black Forest (Nordschwarzwald, NBF). Surfaces of Sphagnum carpets were marked with plastic mesh and one year later the production of plant matter was harvested. Metal concentrations were determined in acid digests using sector field ICP-MS employing well established analytical procedures. Up to 12 samples (40 x 40 cm) were collected per site, and 6-10 sites were investigated per bog. Variations within a given sampling site were in the range 2.3-4x for Pb concentrations, 1.8-2.5x for Ti concentrations, 3-8.3x for Pb/Ti, 5.6-7.8x for Pb accumulation rates, and 2.3-6.4x for Ti accumulation rates. However, the median values of these parameters for the sites (6-10 per bog) were quite consistent. The mosses from the bogs in NBF exhibited significantly greater productivity (187-202 g m(-2) a(-1)) compared to the OB peat bogs (71-91 g m(-2) a(-1)), and these differences had a pronounced effect on the Pb and Ti accumulation rates. Highly productive mosses showed no indication of a "dilution effect" of Pb or Ti concentrations, suggesting that more productive plants were simply able to accumulate more particles from the air. The median rates of net Pb accumulation by the mosses are in excellent agreement with the fluxes obtained by direct atmospheric measurements at nearby monitoring stations in both regions (EMEP and MAPESI data).