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• 38 tree species were tested for the phytomanagement of different marginal lands. • O. carpinifolia performed well on the three sites compared to the nursery standard. • The PTE contents in the trees strongly differed depending on the species. • S. aquatica grandis exhibited the highest accumulation capacity at the three sites. The use of fast-growing trees producing a high quantity of biomass can bring significant practical and economic benefits to the reclamation of marginal lands. The present study aims to identify new shrub/tree species to offer a wider range of shrubs/trees useful for phytomanagement practices. We implemented three experimental sites in France of 1 ha each (Thann, Carrières-sous-Poissy and Leforest) contaminated by different potentially toxic elements (PTE) with a total of 38 different tree species. After two years of growth, the element concentrations in stem and leaf biomasses, tree survival rate and growth of plants were assessed. Although the three sites had elevated concentrations of total PTE and nutrients in their soil, the element contents in the trees strongly differed depending on the species. Alnus subcordata , Platanus orientalis , Ulmus pumila , Ostrya carpinifolia and the Acer species appeared to be well adapted to the drastic conditions of the sites and presented the lowest PTE concentrations in their aboveground biomass. Conversely, the Salix , Populus , Betula and Quercus species, especially Salix aquatica grandis , exhibited the highest accumulations of Cd, Zn and/or Mn at the three sites. Inoculation with the endomycorrhizal fungus Rhizophagus irregularis did not have a significant impact on the growth of the tree species at the three sites after two growing seasons. Overall, the present study offers two options for the phytomanagement of marginal lands. The first option is based on the production of clean biomass, which is useful for plant-based industrial processes (e.g., biomaterials, bioenergy) that could valorize this biomass. The second option is based on the production of TE-enriched biomass that could be better exploited in the eco-catalysis process. [ABSTRACT FROM AUTHOR]

Environmental risk assessment of contaminated soils should ideally be carried out with complementary approaches (chemical and biological) conducted in situ and ex situ. While biological methods based on the assessment of effect and bioaccumulation in bioindicators exist for soil fauna organisms, such as land snails, the methodology is currently limited in the field to 14 metallic elements (MEs). To provide new relevant tools to the stakeholders of polluted fields, the aim of this work is to determine ex situ threshold guide values (ex situ TGVs) , for 15 MEs, 16 polycyclic aromatic hydrocarbons (PAHs) and 7 polychlorinated biphenyls (PCBs). These ex situ TGVs are the usual concentration of contaminants found in the viscera of the bioindicator Cantareus aspersus after 28 days of exposure to uncontaminated soils. The second objective was to assess and validate the relevance of these ex situ TGVs for the interpretation of contamination levels in various European contaminated soils based on global index calculations: i) The sum of the excess of transfers (SETs) and ii) the weighted SETs based on the general toxicity points of each contaminant used to evaluate the risk of transferred MEs, PAHs and PCBs (ERITMEs, ERITPAHs and ERITPCBs, respectively). In addition, the influence of soil physico-chemical properties on accumulation was modelled to better understand their roles in bioavailability. The presented ex situ TGV and the associated indicators (the global sum of the excess of transfers and global ecotoxicological risk) provide a basis by which stakeholders can prioritize the management of polluted soils depending on the risk they may represent. The determination of ex situ TGVs for organic and inorganic compounds provides new tools to characterize excess contaminant transfers, and it will also allow the use of snails for ERAs, notably for common pollutants, such as PAHs and PCBs for which guide values are not available. Unlabelled Image • Threshold guide values (TGVs) available for 38 organic and inorganic contaminants. • TGVs will help in the assessments of the contamination levels and bioavailability. • TGVs guide stakeholders in their choice of polluted soil management practices. [ABSTRACT FROM AUTHOR]

• Influence of soil parameters (e.g., organic matter) on human oral bioaccessibility. • Influence of soil parameters (e.g., organic matter) on bioavailability to snails. • Strong relationships between oral bioaccessibility and bioavailability to snails. • Proposed models to link bioaccessibility to humans and bioavailability to snails. Human health risk assessment (HHRA) and ecotoxicological risk assessment (ERA) of contaminated soils are frequently performed separately and based on total soil concentrations without considering the concepts of mobility, bioaccessibility and bioavailability. However, some chemical and biological assays rarely used in combination can be applied to more accurately assess the exposure of organisms to metal(loid)s and thus to better estimate the links between soil contamination and effects. For humans, the unified bioaccessibility method (UBM) assesses oral bioaccessibility, while for soil fauna such as land snails, the bioaccumulation test reflects the bioavailability of contaminants. The aim of this study is to explore the relationship between oral bioaccessibility and the bioavailability of arsenic, cadmium and lead in twenty-nine contaminated soils. The results show a modulation of bioaccumulation and bioaccessibility of metal(loid)s by soil physicochemical parameters (organic matter especially). For the three metal(loid)s studied, strong relationships were modelled between the UBM and snail tests (0.77 < r² adj. <0.95), depending on the parameters of the linear regressions (contaminant and phases of the UBM test). The original models proposed demonstrate the feasibility of linking bioaccessibility to humans and bioavailability to snails and the relevance of their association for an integrative risk assessment of contaminated soils. [ABSTRACT FROM AUTHOR]