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We show that participatory research approaches can be a useful tool across disciplines and data collection methods to explore the socio-exposome near one of the largest industrial harbors in Europe. We analyzed resident involvement in each project and their capacity to affect structural changes. Longitudinal participatory environmental monitoring studies on lichens, petunias, aquatic systems and groundwater were conducted under the program VOCE (Volunteers for the Citizens' Observation of the Environment), which mobilized nearly 100 volunteers to collect and report data. A community-based participatory health survey, Fos EPSEAL was also carried out during the same period. We describe citizens' involvement in each study following Davis and Ramirez-Andreotta's (2021) 'best practice' grid. We also use residents' insights to refine understanding of the socio-exposome. The region is significantly impacted by industrial pollution and fenceline communities are disproportionately exposed. The community-based participatory health survey documented negative health outcomes among the residents, including a higher prevalence of chronic symptoms and diabetes (e.g., 11.9%) in the Fos-Berre Lagoon region than in other communities. This methodology shows the benefits of the co-production of knowledge in environmental health: not only does it enable epistemological transformations favorable to the vulnerable population, but it also triggered public action (i.e., media and public authorities' attention leading to official expertise reports, filing of collective complaints before the courts). This body of multiple participatory research studies over time is a useful approach to better understand the socio-exposome and health issues in an industrial zone. [Display omitted] • Participatory research is a useful tool to investigate the socio-exposome. • Long-term and highly participatory research resulted in structural changes. • Air, soil, water, fauna, flora and humans are impacted by industrial pollution. • Symptoms and diabetes (12% vs. 8%) were elevated in the fenceline zone. [ABSTRACT FROM AUTHOR] more...

This study proposes global threat scores to prioritize the harmfulness of anthropogenic fine and ultrafine metallic particles (FMP) emitted into the atmosphere at the global scale. (Eco)toxicity of physicochemically characterized FMP oxides for metals currently observed in the atmosphere (CdO, CuO, PbO, PbSO 4 , Sb 2 O 3 , and ZnO) was assessed by performing complementary in vitro tests: ecotoxicity, human bioaccessibility, cytotoxicity, and oxidative potential. Using an innovative methodology based on the combination of (eco)toxicity and physicochemical results, the following hazard classification of the particles is proposed: CdCl 2 ~CdO>CuO>PbO>ZnO>PbSO 4 >Sb 2 O 3 . Both cadmium compounds exhibited the highest threat score due to their high cytotoxicity and bioaccessible dose, whatever their solubility and speciation, suggesting that cadmium toxicity is due to its chemical form rather than its physical form. In contrast, the Sb 2 O 3 threat score was the lowest due to particles with low specific area and solubility, with no effects except a slight oxidative stress. As FMP physicochemical properties reveal differences in specific area, crystallization systems, dissolution process, and speciation, various mechanisms may influence their biological impact. Finally, this newly developed and global approach could be widely used in various contexts of pollution by complex metal particles and may improve risk management. [ABSTRACT FROM AUTHOR] more...

Highlights: [•] Green manures plants were tested for quality restoration of soils polluted by metal(loid)s. [•] Bioavailability and ecotoxicity of metal(loid)s were measured. [•] Borage and mustard improve polluted soil quality. [•] Phytoremediation decreases ecotoxicity and quantity of bioaccessible metal(loid)s. [Copyright &y& Elsevier] more...

The ultimate strength of bolted and dowelled connections in timber members at ambient temperatures have been assessed using Johansen’s yield equations in Europe and USA. More recently, several researchers have begun to investigate the strength of bolted and dowelled connections at elevated temperatures. Research has been carried out at the University of Canterbury to investigate the application of Johansen’s yield equations to the prediction of the failure strength of bolted connections in fire conditions. A series of single bolted connections using steel side plates was heated at constant temperature for several hours, then loaded to failure and used to determine the embedment strength of the wood over a range of temperatures from ambient to 300°C. The temperature-dependent embedment strengths are employed in Johansen’s equations for connections using a central steel plate as well as connections using steel and wood side members. Comparisons are also being made with the results of several similar connections tested in fire conditions and show considerable promise for predicting failure of such joints. A proposal for implementation of an easy-to-use approach for the prediction of the fire resistance of bolted joints is discussed in the paper, based on an extension of the Johansen’s yield equations to fire conditions, including a model for the variation of the embedment strength with temperature. [ABSTRACT FROM AUTHOR] more...

The effectiveness of a constrained-layer damping treatment in dissipating energy and thereby augmenting the system damping is contingent on the viscoelastic polymer having a fairly significant value of material loss factor. A monolithic viscoelastic polymer tends to be lossy over a fairly narrow temperature range, corresponding to the material being in the transition state. At temperatures below this range, the viscoelastic polymer displays glassy behavior, whereas for higher temperatures, it displays rubbery behavior. In either case, the material loss factor reduces sharply and the effectiveness of the damping treatment is severely degraded. A gradient viscoelastic polymer layer, for which the properties vary through the thickness of the layer, can increase the temperature range of effectiveness of the damping treatment. This is because different regions through the thickness enter transition at different temperatures, and so the gradient polymer as a whole provides damping augmentation over a broader temperature range. Classical constrained-layer damping treatments with monolithic polymeric damping layers routinely assume a uniform shear strain through the thickness of the damping layer. However, because the shear modulus of the gradient viscoelastic polymer can vary by up to two-three orders of magnitude through the thickness, the shear strain can also be expected to vary substantially through the thickness. Consequently, a new analysis is developed with the gradient viscoelastic polymer modeled as comprising N discrete sublayers, each with its distinct properties and each assigned an independent shear degree of freedom. Simulation results are presented for a gradient polymer comprising N = 2 discrete sublayers. The results of the study are used to understand the underlying physics. It is seen that ideally, the glassy temperature of the two sublayers should be approximately similar. Further, the treatment is most effective if the sublayer that goes into glass transition at higher temperatures has a lower rubbery modulus than the sublayer going into glass transition at lower temperatures. [ABSTRACT FROM AUTHOR] more...

The extensive use of pesticides combined with their persistence in the environment requires new methodologies to assess more effectively the population exposure to pesticides via air pollution. Biomonitoring pesticides with lichens has been poorly documented, although it represents a complementary approach to the usual active samplings, with an exposure to pesticides accumulated and integrated over several months. An optimized extraction procedure from the lichen Xanthoria parietina followed by a gas chromatographic-tandem mass spectrometric analysis is proposed here to quantify simultaneously 48 pesticides considered in France as priority active substances to monitor in the air. This method has been applied to lichen samples collected in 24 sites in southern France covering urban, industrial, and agricultural areas in order to identify potential contrasts related to anthropogenic activities. Fifteen pesticides (six fungicides, five insecticides, and four herbicides), including four active compounds currently banned by EU legislation, were detected in at least one site. Lindane, diflufenican, difenoconazole, and boscalid were the most common pesticides found in all sites. Urban sites appeared generally less contaminated compared to industrial and rural ones, but a strong heterogeneity was noticed between locations. The biomonitoring with lichens revealed unexpected contaminated areas, partly due to the use of herbicides for vegetation control in industrial and railway installations. The spatial distribution also suggests an input of pesticides by atmospheric transport at the local and regional scales., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.) more...

2,4,6-tribromophenol (TBP) is implied in the production of brominated flame retardants but is also a major chlorination by-product in seawater. A growing number of studies indicate that TBP is highly toxic to the marine biota, but the contribution of anthropogenic sources among natural production is still under question concerning its bioaccumulation in marine organisms. Here, several water sampling campaigns were carried out in the industrialized Gulf of Fos (northwestern Mediterranean Sea, France) and clearly showed the predominant incidence of industrial chlorination discharges on the TBP levels in water, at the 1-10 ng L -1 level in average and reaching up to 580 ng L -1 near the outlets. The bioaccumulation of TBP was measured in 90 biota samples from the Gulf of Fos. The concentrations found in European conger muscle tissues (140-1000 ng g -1 lipid weight, in average), purple sea urchin gonads (830-880 ng g -1 lipid weight, in average), and Mediterranean mussel body (1500-2000 ng g -1 lipid weight, in average) were above all published references. Significant correlations with fish length (European conger) and gonad somatic index (purple sea urchin) were also identified. Comparatively, fish, urchins and mussels from other Mediterranean sites analyzed within this study showed a lower bioaccumulation level of TBP, consistently with what found elsewhere. Industrial outflows were thus identified as hotspots for TBP in seawater and marine organisms. The environmental risk assessment indicated a high potential toxicity in the industrial Gulf of Fos, in particular near the outlets, and a limited threat to human but toxicological references are lacking., (Copyright © 2022 Elsevier Ltd. All rights reserved.) more...

Objectives: We sought to determine whether the residents living closer to the core industrial zone (Fos-sur-Mer) had higher trace metals blood and urinary levels than residents who lived further away (Saint-Martin-de-Crau)., Materials and Methods: As part of The INDEX study, we measured the following trace metals into blood and urine samples of 138 participants (80 in the core industrial zone and 58 in the reference area): Antimony, Arsenic, Cadmium, Chromium, Cobalt, Mercury, Nickel, Lead and Vanadium. Participants were recruited using a stratified random sampling method and had to meet the following inclusion criteria: 30-65 years old, living in the area since at least 3 years, not working in the industrial sector, non-smoker. We used single-pollutant multivariate linear regression models, using substitution when censored data were under 15 % and Tobit models alternatively, adjusting for personal physiological, social, dietary, housing characteristics and leisure activities. We also measured these trace metals in samples of lichens (Xanthoria parietina) and atmospheric particles (PM 2.5 )., Results: We showed higher lichen and air levels of several metals (Cd, Cr, Co, Ni and Pb) in the exposed area. Living close to the core industrial zone was significantly associated with an increase in blood levels of lead (adjusted geometric mean = 17.2 [15.8-18.7] vs 15.1 [13.7-16.7] µg.L -1 , p < 0.05). We report significant increase of some metals urinary levels among residents of the industrial port zone, as the result of the use of the environment, itself contaminated by industrial activities: dietary history of self-consumption of vegetables (Cadmium), eggs and poultries (Vanadium). However, Vanadium levels were greater among self-consumers of poultry in the reference area and gardeners had circulatory levels of Lead greater than non-gardeners only in the reference area. Consumption of non-local sea-products increased the level of Cadmium., Conclusions: These results brought interesting clues, in complement to national programs, regarding the exposure to trace metals of residents living in a major industrial harbor., (Copyright © 2022 Elsevier GmbH. All rights reserved.) more...

The bioaccumulation of metals (As, Cd, Co, Cr, Cu, Ni, Pb, Sb, V, Zn, Al, Fe) and organochlorine compounds (PCDD-Fs and PCBs) was assessed in soils and vegetables of 3 sites of contrasted anthropogenic influence (rural and industrial-urban areas). Cultivated soils in industrial areas exhibited diffuse pollution in organochlorine pollutants (PCBs and PCDD-Fs). The pollutant levels encountered in vegetables were always lower than the EU regulatory or recommended values. However, the contents measured in vegetables cultivated near industrialized areas were significantly higher than those observed in rural areas. This was notably the case for Co, Cd, Cr, Ni, Pb, V, NDL- and DL-PCB, PCDD, and PCDF. The leaf pathway appeared as the main absorption pathway for many contaminants. The results suggested that population exposure to pollutants was mainly caused by vegetable ingestion. In the vegetables and soils, the toxicity was mainly caused by the V, Co, Cd, and Pb contents to which can be added As and PCDD-Fs for soils. Therefore, the proximity of vegetable crops to highly anthropised areas has led to long-term exposure of vegetables and soils to air pollutants, leading to an accumulation in the food chain and thus a risk for human health., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.) more...

The bioaccumulation of PAHs and metal elements in the indigenous lichens Xanthoria parietina was monitored during two years at a quarterly frequency, in 3 sites of contrasted anthropic influence. The impact of the meteorological factors (temperature, relative humidity, rainfall, wind speed) was first estimated through principal component analysis, and then by stepwise multilinear regressions to include wind directions. The pollutants levels reflected the proximity of atmospheric emissions, in particular from a large industrial harbor. High humidity and mild temperatures, and in a lower extent low wind speed and rainfall, also favored higher concentration levels. The contributions of these meteorological aspects became minor when including wind direction, especially when approaching major emission sources. The bioaccumulation integration time towards meteorological variations was on a seasonal basis (1-2 months) but the wind direction and thus local emissions also relied on a longer time scale (12 months). This showed that the contribution of meteorological conditions may be prevalent in remote places, while secondary in polluted areas, and should be definitely taken into account regarding long-term lichen biomonitoring and inter-annual comparisons. In the same time, a quadruple sampling in each site revealed a high homogeneity among supporting tree species and topography. The resulting uncertainty, including sampling, preparation and analysis was below 30% when comfortable analytical conditions were achieved. Finally, the occurrence of unexpected events such as a major forest fire, permitted to evaluate that this type of short, although intense, events did not have a strong influence on PAH and metals bioaccumulation by lichen., (Copyright © 2021. Published by Elsevier B.V.) more...

This study aimed at elucidating the long-term efficiency of soil remediation where chemical stabilization of arsenic (As) contaminated soil using zerovalent iron (Fe) amendments was applied. A combination of chemical extraction and extended X-Ray absorption fine structure (EXAFS) spectroscopy technique was applied on soils collected from five laboratory and field experiments in Sweden and France. All soils were treated with 1 wt% of zerovalent Fe grit 2-15 years prior to the sampling. The results indicate that all studied soils, despite the elapsed time since their amendment with Fe grit, had substantial amounts of ferrihydrite and/or lepidocrocite. These metastable and the most reactive Fe (oxyhydr)oxides (mainly ferrihydrite) were still present in substantial amounts even in the soil that was treated 15 years prior to the sampling and contributed most to the As immobilisation in the amended soils. This increases confidence in the long-term efficiency of As immobilisation using zerovalent Fe amendments. Both applied methods, sequential extraction and EXAFS, were in line for most of the samples in terms of their ability to highlight As immobilisation by poorly crystalline Fe phases., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.) more...

Water chlorination is the most widely used technique to avoid microbial contamination and biofouling. Adding chlorine to bromide-rich waters leads to the rapid oxidation of bromide ions and leads to the formation of brominated disinfection by-products (bromo-DBPs) that exert adverse effects on various biological models. Bromo-DBPs are regularly encountered within industrialized embayments, potentially impacting marine organisms. Of these, bromoform, tribromoacetic acid and tribromophenol are among the most prevalent. In the present study, we tested the potential toxicity and genotoxicity of these disinfection by-products, using sea urchin, Paracentrotus lividus, embryos. We highlighted that tribromophenol showed higher toxicity compared to bromoform and tribromoacetic acid. Furthermore, a synergistic effect was detected when tested in combination. Pluteus cells exposed for 1 h to mixtures of DBPs at several concentrations demonstrated significant DNA damage. Finally, when compared to a non-exposed population, sea urchins living in a bromo-DPB-polluted area produced more resistant progenies, as if they were locally adapted. This hypothesis remains to be tested in order to better understand the obvious impact of complex bromo-DBPs environments on marine wildlife. more...

We conducted a dendrochemical study in order to evaluate the exposure of territories and populations to different types of pollutants and to characterise the history of pollution in one of the most intensely industrialised areas of Europe: the industrial port zone of Fos, also heavily urbanised. To perform the study, two tree species have been selected, Pinus halepensis and Populus nigra, on a rural plot located roughly 20 km away from the industrial harbour, an urban plot located in the city of Fos-sur-Mer and an industrial plot. Our study indicated that poplar was a more relevant model for the dendrochemical studies, exhibiting a higher bioaccumulation capacity than pine except for Hg, Sb and Mn. Moreover, thanks to this work, we observed significant exposure of the trees in the urban and industrial areas to As, Cd, Co, Cu, Mo, Sb, Zn, Al, Ca, and Mg, highlighting the exposure of the territory and populations living in the vicinity of the industrial harbour. The temporal variability of the concentrations measured in the tree rings corresponds to the increasing industrialisation of the territory as well as to the evolution of the industrial processes. Thus, this project highlighted the exposure of the Gulf of Fos to atmospheric emissions (industrial, road and urban) of the industrial harbour as well as the changes over time. It also pointed out the relevance of using dendrochemistry to measure atmospheric exposure of metals and metalloids and its temporal variability., (Copyright © 2018 Elsevier Ltd. All rights reserved.) more...

Lichen samples from contrasted environments, influenced by various anthropic activities, were investigated focusing on the contaminant signatures according to the atmospheric exposure typologies. Most of the contaminant concentrations measured in the 27 lichen samples, collected around the industrial harbor of Fos-sur-Mer (France), were moderate in rural and urban environments, and reached extreme levels in industrial areas and neighboring cities (Al up to 6567 mg kg -1 , Fe 42,398 mg kg -1 , or ΣPAH 1417 μg kg -1 for example). At the same time, a strong heterogeneity was noticed in industrial samples while urban and rural ones were relatively homogeneous. Several metals could be associated to steel industry (Fe, Mn, Cd), road traffic, and agriculture (Sb, Cu, Sn), or to a distinct chemical installation (Mo). As well, PCDFs dominated in industrial samples while PCDDs prevailed in urban areas. The particularities observed supported the purpose of this work and discriminated the contributions of various atmospheric pollution emission sources in lichen samples. A statistical approach based on principal component analysis (PCA) was applied and resolved these potential singularities into specific component factors. Even if a certain degree of mixing of the factors is pointed out, relevant relationships were observed with several atmospheric emission sources. By this methodology, the contribution of industrial emissions to the atmospheric metal, PAH, PCB, and PCDD/F levels was roughly estimated to be 60.2%, before biomass burning (10.2%) and road traffic (3.8%). These results demonstrate that lichen biomonitoring offers an encouraging perspective of spatially resolved source apportionment studies. more...

At the global scale, foliar metal transfer occurs for consumed vegetables cultivated in numerous urban or industrial areas with a polluted atmosphere. However, the kinetics of metal uptake, translocation and involved phytotoxicity was never jointly studied with vegetables exposed to micronic and sub-micronic particles (PM). Different leafy vegetables (lettuces and cabbages) cultivated in RHIZOtest® devices were, therefore, exposed in a greenhouse for 5, 10 and 15days to various PbO PM doses. The kinetics of transfer and phytotoxicity was assessed in relation to lead concentration and exposure duration. A significant Pb accumulation in leaves (up to 7392mg/kg dry weight (DW) in lettuce) with translocation to roots was observed. Lead foliar exposure resulted in significant phytotoxicity, lipid composition change, a decrease of plant shoot growth (up to 68.2% in lettuce) and net photosynthesis (up to 58% in lettuce). The phytotoxicity results indicated plant adaptation to Pb and a higher sensitivity of lettuce in comparison with cabbage. Air quality needs, therefore, to be considered for the health and quality of vegetables grown in polluted areas, such as certain megacities (in China, Pakistan, Europe, etc.) and furthermore, to assess the health risks associated with their consumption., (Copyright © 2016. Published by Elsevier B.V.) more...

At the global scale, high concentrations of particulate matter (PM) enriched with metal(loid)s are currently observed in the atmosphere of urban areas. Foliar lead uptake was demonstrated for vegetables exposed to airborne PM. Our main objective here was to highlight the health risk associated with the consumption of vegetables exposed to foliar deposits of PM enriched with the various metal(loid)s frequently observed in the atmosphere of urban areas (Cd, Sb, Zn and Pb). Leaves of mature cabbage and spinach were exposed to manufactured mono-metallic oxide particles (CdO, Sb2O3 and ZnO) or to complex process PM mainly enriched with lead. Total and bioaccessible metal(loid) concentrations were then measured for polluted vegetables and the various PM used as sources. Finally, scanning electronic microscopy coupled with energy dispersive X-ray microanalysis was used to study PM-phyllosphere interactions. High quantities of Cd, Sb, Zn and Pb were taken up by the plant leaves. These levels depended on both the plant species and nature of the PM, highlighting the interest of acquiring data for different plants and sources of exposure in order to better identify and manage health risks. A maximum of 2% of the leaf surfaces were covered with the PM. However, particles appeared to be enriched in stomatal openings, with up to 12% of their area occupied. Metal(loid) bioaccessibility was significantly higher for vegetables compared to PM sources, certainly due to chemical speciation changes. Taken together, these results confirm the importance of taking atmospheric PM into account when assessing the health risks associated with ingestion of vegetables grown in urban vegetable crops or kitchen gardens. more...

We investigate the effect of both foliar and root uptake of a mixture of metal(loid)s on the fatty acid composition of plant leaves. Our objectives are to determine whether both contamination pathways have a similar effect and whether they interact. Lactuca sativa L. were exposed to fine process particles enriched with metal(loid)s in an industrial area. Data from a first experiment were used to conduct an exploratory statistical analysis which findings were successfully cross-validated by using the data from a second one. Both foliar and root pathways impact plant leaf fatty acid composition and do not interact. Z index (dimensionless quantity), weighted product of fatty acid concentration ratios was built up from the statistical analyses. It provides new insights on the mechanisms involved in metal uptake and phytotoxicity. Plant leaf fatty acid composition is a robust and fruitful approach to detect and understand the effects of metal(loid) contamination on plants., (Copyright © 2013 Elsevier Ltd. All rights reserved.) more...

Due to diffuse atmospheric fallouts of process particles enriched by metals and metalloids, polluted soils concern large areas at the global scale. Useful tools to assess ecotoxicity induced by these polluted soils are therefore needed. Earthworms are currently used as biotest, however the influence of specie and earthworm behaviour, soil characteristics are poorly highlighted. Our aim was therefore to assess the toxicity of various polluted soils with process particles enriches by metals and metalloids (Pb, Cd, Cu, Zn, As and Sb) collected from a lead recycling facility on two earthworm species belonging to different ecological types and thus likely to have contrasted behavioural responses (Eiseina hortensis and Lumbricus terrestris). The combination of behavioural factors measurements (cast production and biomass) and physico-chemical parameters such as metal absorption, bioaccumulation by earthworms and their localization in invertebrate tissues provided a valuable indication of pollutant bioavailability and ecotoxicity. Soil characteristics influenced ecotoxicity and metal uptake by earthworms, as well as their soil bioturbation., (Copyright © 2013 Elsevier Ltd. All rights reserved.) more...

In order to revegetate an industrial soil polluted by trace metals and metalloids (As, Pb, Cu, Cd, Sb), the impact of pollution on three plant species, Solanum nigrum and Agrostis capillaris, both native species in an industrial site, and Vicia faba, a plant model species, is studied. Following the study of soil pollution from the industrial wasteland of Auzon, it appears that the As is the principal pollutant. Particular attention is given to this metalloid, both in its content and its speciation in the soil that the level of its accumulation in plants. In V. faba and A. capillaris, the trace metals and metalloids inhibit the biomass production and involve a lipid peroxidation in the leaves. Furthermore, these pollutants cause a photosynthesis perturbation by stomatal limitations and a dysfunction of photosystem II. Whatever the plant, the As content is less than 0.1 percent of dry matter, the majority of As absorbed is stored in the roots which play the role of trap organ. In parallel, the culture of S. nigrum decreases significantly the exchangeable and weakly adsorbed fraction of As in rhizospheric soil. This study has highlighted the ability of tolerance to trace metals of S. nigrum and to a lesser extent A. capillaris. Our data indicate that V. faba is not tolerant to soil pollution and is not a metallophyte species., (Copyright © 2012 Elsevier Inc. All rights reserved.) more...

Mine wastes have been considered as a source of heavy metal (HM) contamination in the environment and negatively impact many important ecosystem services provided by soils. Plants like Miscanthus, which tolerate high HM concentrations in soil, are often used for phytoremediation and provide the possibility to use these soils at least for the production of energy crops. However, it is not clear if plant growth at these sites is limited by the availability of nutrients, mainly nitrogen, as microbes in soil might be affected by the contaminant. Therefore, in this study, we investigated in a greenhouse experiment the response of ammonia-oxidizing microbes in the root-rhizosphere complex of Miscanthus × giganteus grown in soils with different levels of long-term arsenic (As) and lead (Pb) contamination. Quantitative PCR of the ammonia monooxigenease gene (amoA) was performed to assess the abundance of ammonia-oxidizing bacteria (AOB) and archaea (AOA) at two different points of plant growth. Furthermore, bulk soil samples before planting were analyzed. In addition, terminal restriction fragment length polymorphism (T-RFLP) analysis was used to investigate the diversity of archaeal amoA amplicons. Whereas high concentrations of As and Pb in soil (83 and 15 g/kg, respectively) resulted independent from plant growth in a clear reduction of AOA and AOB compared to the control soils with lower HM contents, in soils with contamination levels of 10 g/kg As and 0.2 g/kg Pb, only AOB were negatively affected in bulk soil samples. Diversity analysis of archaeal amoA genes revealed clear differences in T-RFLP patterns in response to the degree of HM contamination. Therefore, our results could clearly prove the different response patterns of AOA and AOB in HM-contaminated soils and the development of archaeal amoA phylotypes which are more tolerant towards HMs in soil samples from the areas that were impacted the most by mining waste, which could contribute to functional redundancy of ammonia-oxidizing microbes in soils and stability of nitrification pattern. more...