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International audienceConsidering the limited number of bioindicators available to assess soil quality, a national research programme was set up in France to develop such indicators (2006-2012), the "Bioindicator" programme. This programme tested 47 biological parameters (i.e. microorganisms, fauna, flora) including earthworms, in several sites differing in terms of land use, contamination type - PAHs or metals - and pollution levels. The present study proposes some study objectives for bioindicator approaches, based on the earthworm results from the programme. Therefore, different earthworm descriptors were tested at the community level (e.g. abundance, biomass, species and functional structures, and ecological traits) as well as the organism level (i.e. measuring the metallothionein coding gene expression level in earthworms). The present results, obtained from the programme's spring 2009 sampling campaign, discriminated among the different descriptors and showed that earthworm and endogeic abundance as well as the individual weight of endogeics seem to be good indicators in non-contaminated (cultivated) sites, while the ecological structure, namely the proportion of anecic vs. endogeic species, and the proportion of non-vulnerable species should be used as indicators of contaminated soils. Furthermore, the first results obtained for Lumbricus terrestris and L. rubellus rubellus are encouraging as they show that metallothionein expression increases in metal-contaminated soils. The relevance of these descriptors, which have to be considered in study objectives, requires the analysis of 2010 results

Bacteriophages are potentially useful models for studying the fate and transport of pathogenic enteric viruses and other biocoUoids through soil and ground water. To be useful for this purpose they must be capable of surviving for significant periods in ground water and demonstrate low adsorption to soil surfaces. The purpose of this study was to evaluate the survival of two bacteriophages which have been shown to adsorb poorly to soils, i.e. the Escherichiacoli phages MS-2 and PRD-1 which infect Salmonellatyphimurium. Samples of ground water from various regions of North America were inoculated with the test phages and incubated at temperatures near the ambient ground water temperature of the collection site. At 7°C no significant inactivation of the phages occurred over a period of 80 days. At higher temperature (10 to 23°C) PRD-1 was far more resistant to inactivation than MS-2, persisting for periods of 7 to 10 times longer in most water samples.

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As a part of an air-pollution biomonitoring survey, a procedure using inductively coupled plasma-mass spectrometry (ICP-MS) and microwave digestion was developed to achieve a high sample throughput and guarantee the accuracy of the results. This article presents an analytical method to measure 22 trace elements. As, Ba, Cd, Ce, Co, Cr, Cs, Cu, Fe, Hg, La, Mo, Ni, Pb, Rb, Sb, Sr, Th, Tl, U, V, W were analyzed in 563 mosses collected in France. The digestion was performed in polytetrafluoroethylene (PTFE) vessel using the mixture HNO3-H2O2-HF. The data were reprocessed taking into account the drift curve calculated for each element. The detection limits (DL) calculation was based on the standard deviations of the reagent blanks concentrations. The DL varied from one batch to another, because of the heterogeneity of the mosses' elemental contents. The DL ranged between 0.001 microg/g (Cs, Tl) and 70 microg/g (Fe) and were mainly around 0.01 microg/g (As, Cd, Ce, Co, Hg, La, Mo, Sb, Sr, U, V, W). The detection limits obtained were in agreement with the concentrations observed in the samples, except for Hg and Ni. The reproducibility between duplicates and the analytical precision were near 10%. The procedure was tested with the mosses' reference materials.