Evaluation of uptake of the cytostatic methotrexate in Elliptio complanata mussels by LC–MS/MS

Environmental Science and Pollution Research - Aquatic organisms are continuously exposed to emerging contaminants coming from urban effluents of wastewater treatment plants. The contamination of...     

Prenatal diagnosis of respiratory chain deficiency by direct mutation screening

Respiratory chain deficiency (RCD) is responsible for a clinically heterogeneous group of early-onset untreatable disorders. Enzymological prenatal diagnosis (PD) can only be offered to a fraction of families. Moreover, due to the two-fold genetic origin of the respiratory chain (nuclear and mitochondrial DNA) and owing to the large number of nuclear genes involved in the respiratory chain assembly, maintenance and functioning, the identification of the disease causing gene in a given family remains challenging. Here, we report on PD of RCD by direct screening of NDUFV1, SDH-Fp, SCO1 and SURF1 mutations in five unrelated families with complex I, II and IV deficiency, respectively. The identification of the disease-causing gene in a given family with RCD is a major issue to provide both adequate genetic counselling and early, reliable PD. Copyright © 2001 John Wiley & Sons, Ltd.     

Exposure to particulate matter in traffic: A comparison of cyclists and car passengers

Emerging evidence suggests that short episodes of high exposure to air pollution occur while commuting. These events can result in potentially adverse health effects. We present a quantification of the exposure of car passengers and cyclists to particulate matter (PM). We have simultaneously measured concentrations (PNC, PM2.5 and PM10) and ventilatory parameters (minute ventilation (VE), breathing frequency and tidal volume) in three Belgian locations (Brussels, Louvain-la-Neuve and Mol) for 55 persons (38 male and 17 female). Subjects were first driven by car and then cycled along identical routes in a pairwise design. Concentrations and lung deposition of PNC and PM mass were compared between biking trips and car trips.Mean bicycle/car ratios for PNC and PM are close to 1 and rarely significant. The size and magnitude of the differences in concentrations depend on the location which confirms similar inconsistencies reported in literature. On the other hand, the results from this study demonstrate that bicycle/car differences for inhaled quantities and lung deposited dose are large and consistent across locations. These differences are caused by increased VE in cyclists which significantly increases their exposure to traffic exhaust. The VE while riding a bicycle is 4.3 times higher compared to car passengers. This aspect has been ignored or severely underestimated in previous studies. Integrated health risk evaluations of transport modes or cycling policies should therefore use exposure estimates rather than concentrations.     

Uptake of Cd(II) and Pb(II) by microalgae in presence of colloidal organic matter from wastewater treatment plant effluents

The present study addresses the key issue of linking the chemical speciation to the uptake of priority pollutants Cd(II) and Pb(II) in the wastewater treatment plant effluents, with emphasis on the role of the colloidal organic matter (EfOM). Binding of Cd(II) and Pb(II) by EfOM was examined by an ion exchange technique and flow field-flow fractionation coupled to inductively coupled plasma mass spectrometry in parallel to bioassays with green microalga Chlorella kesslerii in ultrafiltrate (<1 kDa) and colloidal isolates (1 kDa to 0.45 μm). The uptake of Cd by C. kesslerii was consistent with the speciation analysis and measured free metal ion concentrations, while Pb uptake was much greater than that expected from the speciation measurement. Better understanding of the differences in the effects of the EfOM on Cd(II) and Pb(II) uptake required to take into account the size dependence of metal binding by EfOM.     

DEVELOPMENT AND EVALUATION OF MULTIPLE‐OBJECTIVE DECISION‐MAKING METHODS FOR WATERSHED MANAGEMENT PLANNING1

ABSTRACT: Making decisions for environmental management is a complex task due to the multiplicity and diversity of technological choices. Furthermore, the exploitation of natural resources and the preservation of the natural environment imply objectives that are often in conflict within a sustainable development paradigm. Managers and other decision makers require techniques to assist them in understanding strategic decision making. This paper illustrates the use of a multiple‐objective decision‐making methodology and an integrative geographical information system‐based decision‐making tool developed to help watershed councils prioritize and evaluate restoration activities at the watershed level. Both were developed through a multidisciplinary approach. The decision‐making tool is being applied in two watersheds of Oregon's Willamette River Basin. The results suggest that multiple‐objective methods can provide a valuable tool in analyzing complex watershed management issues.     

Effect of nonylphenol surfactants on fungi following the application of sewage sludge on agricultural soils

The effect of nonylphenol on fungi following the application of contaminated sewage sludge on agricultural soil was studied in laboratory experiments. Nonylphenol bioavailability and adsorption were determined in the soil alone and soil-sludge mixtures. Mixing the soil with sludge made it possible to measure the nonylphenol concentration in the soil solution, which comprised between 6.6 x 10(-6) and 3.8 x 10(-7) M, according to the sludge. We then examined the dose-response relationship between nonylphenol concentration in the culture medium and both biomass production and germination rate of the spores from several strains of filamentous fungi. When applied in this range of concentration, nonylphenol was without noticeable short-term effect on these endpoints. Long-term exposure of fungi to nonylphenol was also assessed. The most intensive effect was a strong stimulation of spore production and germination in Fusarium oxysporum Schlechtendahl. Biomass production by the Fusarium strains also increased. Finally, nonylphenol was shown to induce laccase production in Trametes versicolor. We conclude that the potential of nonylphenol to adversely affect several soil fungi remains low.