Observation of changes in urinary excretion of thorium in humans following ingestion of a therapeutic soil

The study investigated the changes in urinary thorium excretion by humans following ingestion of a therapeutic soil, which contains about 10 ppm of thorium. This well-known healing earth in Germany has been considered as an alternative medicine for diarrhoea and gastric hyper-acidity. Six adult volunteers ingested this therapeutic soil in varying quantities for 1-15 days at levels approximating those described in the package insert of the medicine (10-60 g of soil per day). The subjects ingested about 0.1-0.6 mg of thorium daily, which is 100-600 times higher than the normal daily intake of about 1 microg thorium in Germany. All 24-h urine samples collected from the subjects during pre-ingestion, ingestion and post-ingestion periods of the soil were analyzed for (232)Th using inductively coupled plasma mass spectrometry (ICP-MS). The measured excretion values varied in a wide range. Apparently, the high thorium amounts administered did not increase the (232)Th excretion in urine as expected, suggesting that this soil ingestion will not result in a considerably higher and harmful uptake of thorium into the human body.     

Advanced techniques in air pollution†

Specific usage of neutron activation analysis, charged particle analysis, y photons analysis, G.C.M.S. coupling, stable isotope dilution techniques, are discussed.

Dust collected on filters, oxygenated compounds in exhaust gases from car engines, nitrogen oxides, have thus been determined.

Special calibration methods for ozone, and remote detection by Lidar Raman are also described.     

First evidence of large-scale PAH trends in French soils

Polycyclic aromatic hydrocarbons (PAHs) are widespread organic pollutants. Soils are a reservoir of PAHs because some soil constituents favour PAH accumulation. Therefore, soil is a key indicator of the degree of contamination. So far, studies mapping soil PAH levels over large territories are very rare. Here, we report the first nation-wide maps of soil PAHs in France. Results were obtained within the French National Soil Monitoring Network, which is the first European network monitoring systematically soil PAHs. We used advanced geostatistics to map PAH distribution over the whole French territory. Our results show clear trends of PAH levels at the nation scale. For instance, the highest PAH levels are found in Northern and Eastern France. This high contamination is explained by the intense industrial activity of these regions during the last century. High levels of PAH are also found near some coastlines. This observation could be explained by long-range atmospheric transportation. In addition, we found that light PAHs are rarely found in French topsoils.     

Developing a common currency for stable isotope analyses of nesting marine turtles

Understanding geospatial linkages is critical to the development of appropriate management and conservation strategies for migratory species. Stable isotope analysis is a powerful tool that is performed routinely across taxa to unravel migratory connectivity. Marine turtles are a highly migratory and widely distributed taxon, but are largely studied at breeding areas. Isotopic values of several slow turnover rate tissues have been used to identify often distant foraging areas. However, as more isotopic data from various tissues become available, the relationships between tissues need to be calculated to permit meta-analyses to elucidate isotopic patterns across broader spatiotemporal scales. We used several commonly collected tissues (blood, skin, fresh eggs and unhatched eggs) collected simultaneously from loggerhead turtles (Caretta caretta) to develop a common currency for stable isotope analysis studies conducted on the nesting beach. We found highly significant relationships between the tissue signatures (r ² ranged from 0.83 to 0.96) and developed equations to convert isotopic values from one tissue to another. We examined inter- and intra-clutch isotopic variability and found that a single sampling event over the 4-month nesting season adequately defined the loggerhead female foraging area. Consequently, we propose using unhatched eggs as a common currency in stable isotope studies of nesting loggerheads. Unhatched eggs represent a noninvasive and nondestructive method that enables more extensive (both numerically and spatially) sampling. Given similar physiologies, analogous relationships might be derived in other sea turtle species.     

Maryland Biological Stream Survey: A State Agency Program to Assess the Impact of Anthropogenic Stresses on Stream Habitat Quality and Biota

The Maryland Department of Natural Resources is conducting the Maryland Biological Stream Survey, a probability-based sampling program, stratified by river basin and stream order, to assess water quality, physical habitat, and biological conditions in first through third order, non-tidal streams. These streams comprise about 90% of all lotic water miles in the state. About 300 sites (75 m segments) are being sampled during spring and summer each year. All basins in the state will be sampled over a three-year period, 1995-97. MBSS developments in 1995-96 included (1) an electrofishing capture efficiency correction method to improve the accuracy of fish population estimates, (2) two indices of biotic integrity (IBI) for fish assemblages to identify degraded streams, and (3) land use information for catchments upstream of sampled sites to investigate associations between stream condition and anthropogenic stresses. Based on fish IBI scores at 270 stream sites in six basins sampled in 1995, 11% of non-tidal stream miles in Maryland were classified as very poor, 15% as poor, 24% as fair, and 27% as good. IBIs have not yet been developed for stream sites with catchment areas less than 120 hectares (23% of non-tidal stream miles). IBI scores declined with stream acid neutralizing capacity (ANC) and pH, an association that was also evident for fish species richness, biomass, and density. Low IBI scores were associated with several measures of degraded stream habitat, but not with local riparian buffer width. There was a significant negative association between IBI scores and urban land use upstream of sampled sites in the only extensively urbanized basin assessed in 1995. Future plans for the MBSS include (1) identifying all benthic macroinvertebrate samples to genus, (2) developing benthic macroinvertebrate, herpetofaunal, and physical habitat indicators, and (3) enhancing the analysis of stream condition-stressor associations by refining landscape metrics and using multi-variate techniques.     

Maryland Biological Stream Survey: Development of a Fish Index of Biotic Integrity

As a step towards determining the extent of degradation in non-tidal streams, a multi-metric Index of Biotic Integrity (IBI) based on fish assemblages was developed for the Maryland Biological Stream Survey (MBSS). The MBSS is a probability-based statewide sampling program designed to assess the status of biological resources and to evaluate the effects of anthropogenic activities. We used data from 419 MBSS sites sampled in 1994-95 to develop the IBI. Two distinct geographic strata, corresponding with ecoregional and physiographic boundaries, were identified via cluster analysis and multivariate analysis of variance (MANOVA) as supporting distinctly different species groups. Reference conditions were based on minimally degraded sites. We quantitatively evaluated the ability of various attributes of the fish assemblage (candidate metrics) to discriminate between these reference sites and sites known to be degraded, using statistical tests and classification efficiency. Provisional formulations of the IBI were selected for each region based on high classification efficiency and broad representation of fish assemblage attributes. Fish IBI scores for 1995 MBSS sites spanned a wide range of biological conditions, from good to very poor. Over all six basins sampled in 1995, half of the stream miles fell into the range of good to fair. Roughly 25% of stream miles showed some degradation. The IBI will be used in conjunction with physical and chemical data to answer critical questions about the health of Maryland streams and the relative impacts of human-induced stresses on the state's aquatic systems.     

Different Pla Grafting Techniques on Chitosan

PLA grafting on chitosan has been successfully prepared with two different methods: a direct grafting method and the ROP method. The thermal properties showed that the copolymerization of PLA on the chitosan’s chain by direct grafting is more thermostable than the one obtained by the ROP method.     

Coupling occurs before breakdown during biotransformation of Acid Blue 62 by white rot fungi

Only few data exist on the metabolites produced during the biotransformation of anthraquinonic dyes by white rot fungi (WRF). During the biotransformation of an anthraquinonic dye Acid Blue 62 (ABu62) using Pycnoporus sanguineus MUCL 41582 strain, it was previously demonstrated that the blue colour of the medium turned to red before complete dye decolourisation. To better understand the phenomenon, this study carried out ABu62 biotransformation with five different WRF strains (Coriolopsis polyzona MUCL 38443, Perenniporia ochroleuca MUCL 41114, Perenniporia tephropora MUCL 41562, P. sanguineus MUCL 38531 and Trametes versicolor MUCL 38412) and compared with P. sanguineus MUCL 41582 previously described. A multi-methodological approach (using capillary electrophoresis, mass spectrometry, HPLC, UV, NMR and IR spectroscopies) was developed to characterise the metabolites involved and monitor their apparition. Seven metabolites were commonly found with all strains, suggesting a common metabolic pathway for ABu62 biotransformation. During the first days, dimer and oligomers of the initial ABu62 molecule were observed: the main one absorbed in the 500nm region, explaining the red colour appearance of the medium. This main metabolite was made up of two molecules of ABu62 linked by an azo bond, minus a cyclohexyl moiety. After a longer incubation time, breakdown products were observed. Based on these products characterizations, a bioconversion pathway was proposed.