In situ stabilization of trace metals in a copper-contaminated soil using P-spiked Linz-Donawitz slag

Purpose  

A former wood exploitation revealing high Cu and As concentration of the soils served as a case study for assisted phytoextraction.     

Transfer of radiocarbon liquid releases from the AREVA La Hague spent fuel reprocessing plant in the English Channel

The recent risk assessment by the North-Cotentin Radioecology Group (, 1999) outlined that (14)C has become one of the major sources of the low dose to man through seafood consumption. It was recommended that more data should be collected about (14)C in the local marine environment. The present study aims to respond to this recommendation. The estimation of (14)C activity in marine species is based on concentration factor values. The values reported here ranged from 1x10(3) to 5x10(3)Bqkg(-1)ww/BqL(-1). A comparison was made between the observed and predicted values. The accuracy of (14)C activity calculations was estimated between underestimation by a factor of 2 and over-estimation by 50% (95% confidence interval). However, the use of the concentration factor parameter is based on the biological and seawater compartments being in steady state. This assumption may not be met at short distances from the point of release of discharges, where rapid changes in seawater concentration may be smoothed out in living organisms due to transfer kinetics. The data processing technique, previously published by Fiévet and Plet (2003. Estimating biological half-lives of radionuclides in marine compartments from environmental time-series measurements. Journal of Environmental Radioactivity 65, 91-107), was used to deal with (14)C transfer kinetics, and carbon half-lives between seawater and a few biological compartments were thus estimated.     

Radon, helium and CO2 measurements in soils overlying a former exploited oilfield, Pechelbronn district, Bas-Rhin, France

The Pechelbronn oilfield (Rhine Graben, France), where mining activity ended in the 1960s, has been used for waste disposal for twenty years. Since the wastes are varied, work is underway to identify the discharged materials and their derivatives, as well as to locate and quantify potential discharge sites. Two major goals were assigned to the present work. The first was to identify or refine the location of hidden structures that could facilitate gas emanation up to the surface, by studying soil gas concentrations (mainly ²²²Rn, CO₂, CH₄ and helium) and carbon isotope ratios in the CO₂ phase. The second was devoted to examining, from a health and safety viewpoint, if the use of the oilfield as a waste disposal site might have led to enhanced or modified gas emanation throughout the area.It appeared that CO₂ and ²²²Rn evolution in the whole area were similar, except near some of the faults and fractures that are known through surface mapping and underground observations. These ²²²Rn and CO₂ anomalies made it possible to highlight more emissive zones that are either related to main faults or to secondary fractures acting as migration pathways. In that sense, the CO₂ phase can be used to evaluate ²²²Rn activities distant from tectonic structures but can lead to erroneous evaluations near to gas migration pathways. Dumping of wastes, as well as oil residues, did not appear to have a strong influence on soil gaseous species and emanation. Similarly, enhanced gas migration due to underground galleries and exploitation wells has not been established. Carbon isotope ratios suggested a balance of biological phenomena, despite the high CO₂ contents reached. Other monitored gaseous species (N₂, Ar, H₂ and alkanes), when detected, always showed amounts close to those found subsurface and/or in atmospheric gases.     

Towards a general relationship between climate change and biodiversity: an example for plant species in Europe

Climate change is one of the main factors that will affect biodiversity in the future and may even cause species extinctions. We suggest a methodology to derive a general relationship between biodiversity change and global warming. In conjunction with other pressure relationships, our relationship can help to assess the combined effect of different pressures to overall biodiversity change and indicate areas that are most at risk. We use a combination of an integrated environmental model (IMAGE) and climate envelope models for European plant species for several climate change scenarios to estimate changes in mean stable area of species and species turnover. We show that if global temperature increases, then both species turnover will increase, and mean stable area of species will decrease in all biomes. The most dramatic changes will occur in Northern Europe, where more than 35% of the species composition in 2100 will be new for that region, and in Southern Europe, where up to 25% of the species now present will have disappeared under the climatic circumstances forecasted for 2100. In Mediterranean scrubland and natural grassland/steppe systems, arctic and tundra systems species turnover is high, indicating major changes in species composition in these ecosystems. The mean stable area of species decreases mostly in Mediterranean scrubland, grassland/steppe systems and warm mixed forests.     

Prenatal diagnosis of congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency by steroid analysis in the amniotic fluid of mid-pregnancy: Comparison with HLA typing in 17 pregnancies at risk for CAH

Amniotic fluid (AF) levels of 17-hydroxyprogesterone (17OHP) and testosterone (T) were determined at 16–17 weeks in 17 pregnancies at risk for CAH and results compared to 75 normal controls. The fetus was predicted to be unaffected in 12 cases on the findings of normal AF levels of both 17OHP and T and the latter allowed a correct prediction of fetal sex in all instances. HLA typing confirmed normality in 12 cases revealing 5 carriers, 5 homozygous normal and 2 indeterminate. Steroid levels of the 2 groups were similar. Three fetuses were predicted to be CAH affected on unambiguously high levels of 17OHP and T (in female only). HLA typing was in agreement, and the diagnosis was confirmed in 2 abortuses and a female newborn by physical and hormonal studies. In the last 2 cases AF levels of OHP and T were normal but HLA (A/B/C) genotypes were identical to the CAH affected siblings. Normal physical and hormonal findings in the 2 aborted fetuses would exclude the possibility of an in utero virilizing form of CAH. The discrepancy could be explained on the basis that the fetuses had an allelic form of 21-hydroxylase deficiency or on the basis of recombination (not fully tested). It is concluded that a fully informative prenatal diagnosis of CAH should not rely entirely on HLA typing but on hormonal studies.