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191.
The scientific field of impact assessment encompasses various ‘traditions’, each reflecting a set of particular policy objectives. This paper analyses two types of impact assessment. Regulatory impact analysis focuses on better regulation and competitiveness, while sustainability assessment fosters a holistic approach centred on the values of sustainable development. Through an analysis of the political discourses at the level of the European Union and at the sub-national level of the Flemish Region of Belgium, elements of convergence between the better regulation and sustainable development discourse are identified. The paper analyses how integrated impact assessment can be an integrative tool that allows to merge both discourses and to implement them in day-to-day decision-making. The potential of the existing Flemish regulatory impact analysis framework to be the starting point of an integrated assessment scheme for sustainable development is advocated and motivated.  相似文献   
192.
Water-soluble synthetic polymers are extensively used in cosmetics, detergents and paints. Many end up in wastewater and, later on, in wastewater-treatment plants. In order to gain an insight into their fate in such plants, fluorescence and radioactivity labelings were compared using a lab-scale reactor designed to mimic industrial conditions. Two fermentation media were considered, namely a mixture of E402 and E204 micro-organisms and an activated sludge collected from a water-treatment plant located in the south of France. A sample of low molar mass commercial poly(acrylic acid) (PAA) was labeled by radioactivity with tritium and by coupling the 6-aminofluorescein fluorescent dye. Labeled PAA-containing sludges were allowed to ferment. To monitor the fate of the polymers, aliquots of the fermented mixtures were withdrawn at selected times and centrifuged. Liquid and solid phases were analyzed by scintigraphy or UV spectrometry, depending of the labeling techniques. Both techniques led to similar distributions, c.a. 75% in the supernatant and 25% in the solid phase. Distributions remained constant during the biological tests. There was no degradation of the commercial PAA after aqueous size exclusion chromatography (SEC), in agreement with literature. These features showed that fluorescence-labeling can be used instead of the complex and expensive radiolabeling. The validated fluorescence-based method was then applied to a linear poly(acrylic acid) synthesized by ATRP and labeled with 6-aminofluorescein. There was no significant difference between the commercial and the linear poly(acrylic acid)s. In contrast, a linear PAA with 5% of tert-butyl ester repeating units was predominantly found in the solid phase although adsorption or absorption by micro-organisms could not be demonstrated. The method based on fluorescence labeling should be applicable to other water soluble polymers provided that the dye remains attached to the polymer as it was the case for the studied poly(acrylic acid)s.  相似文献   
193.
Many governmental air pollution control agencies are confronted with a shortage of manpower, both in terms of numbers of people and qualifications of available staff members. This paper discusses a number of techniques which may be used to relieve this manpower shortage. The techniques are discussed in terms of collaboration between state and local agencies; organizational structures which make maximum use of scarce categories of people; program policies which conserve the time of agency staff; operating schemes which save travel time and minimize skills required; and working tools that can be used to get the greatest production with available personnel.  相似文献   
194.
An epidemiological survey was conducted in the Seine estuary and in two smaller and relatively preserved estuaries on the French Atlantic coast in order to estimate the occurrence of liver lesions in European flounder, Platichthys flesus, and also to seek putative risk factors for the recorded pathologies. Four hundred and seventy-eight fish of both sexes and of different size ranges were sampled in the three studied areas, 338 of which in the Seine estuary. All fish were examined for histopathological liver lesions, while DNA adducts and otoliths were analyzed on a subsample. Five categories of hepatic lesions were recorded with the following prevalence for the Seine estuary: 36.7 % inflammations, 8 % parasites (mainly encysted nematodes), 6.5 % foci of cellular alteration (FCA), 5.3 % foci of necrosis or regeneration (FNR), and 1.5 % tumors. Inflammation occurrence increased according to age, contrary to parasitic infestations and FCA which were more prevalent in young fish, notably those of <1 year old (group 0). Tumors were only observed in females of more than two winters. Females exhibited a higher prevalence of tumors (3.0 %) and FCA (6.5 %) than males (0 and 2.6 %, respectively). Parasitic and infectious lesions and FNR were equally distributed in males and females. The prevalence of FNR was also shown to vary according to sampling season, with significantly more occurrences of liver necrosis in the fish collected in summer than in spring. Spatial differences were observed with a higher occurrence of encysted parasites in flounders from the upper Seine estuary, while inflammations predominated in flounders living downstream. Temporal trends were also noted, with an increased prevalence of parasitic infestations, inflammations, and FCA in the 2002–2003 period in comparison to the 1996–1997 one. The three flounder populations from the Seine estuary (Normandy), Ster estuary (Brittany), and Bay of Veys (Normandy) showed different spectra of hepatic lesions. Flounders from the Bay of Veys had relatively few liver lesions as compared to flounders from the two other estuaries. Flounders from the Ster estuary exhibited the highest prevalence of parasites (37.2 %) and inflammations (51.1 %). Finally, FCA and liver tumors occurred at very similar levels in both flounder populations from the Seine and the Ster estuaries. Group 0 flounders inhabiting the upper Seine estuary were more prone to parasitic and pre-neoplastic hepatic lesions and had higher levels of liver DNA adducts than the older ones living downstream. It was postulated that group 0 European flounders may serve as valuable bioindicators for assessing the quality of estuarine waters and the health status of euryhaline fish populations.  相似文献   
195.
Physiological and genetic responses of age 0+ Platichthys flesus were investigated in the eutrophicated and moderately contaminated Vilaine estuary, during a 6-month survey. The main objective of this study was to explore the biological responses of fishes during their juvenile period in an estuarine system in order to detect a possible selective pressure induced by the environmental stress. Our results showed a general convergence in physiological responses along the survey: an increase in genotoxicity was associated with an increase in mRNA expression of ATPase and betaine homocysteine methyltransferase. These results could suggest an increase of cellular damage, energetic request, and detoxification rate related to the growing exposure time to stress. Considering the aging of the cohort, the genetic characteristics of the Vilaine flounder cohort came closer to the one observed in a highly stressed system, the Seine estuary, suggesting a potential selective pressure mainly induced by the chemical stress.  相似文献   
196.
Extensive air pollution studies have been completed in Nashville. One part of the study involved collection of opinions from nearly 8000 people. Opinions were solicited relative to awareness and concern about possible adverse effects of air pollution on health, property, materials, and aesthetics. Responses of the interviewed people are related to several types of pollutant measurements. The results indicate widespread concern about air pollution, and the degree of concern is, in general, closely related to the degree of air contamination experienced by interviewed people. Methodology is discussed, data are analyzed statistically, and conclusions are presented.  相似文献   
197.
In recent decades, many toxicological tests based on in vivo or in vitro models, mainly from mammalian (rat–mouse) and fish species, were used to assess the risks raised by contact or ingestion of molecules of pharmaceutical, agricultural, or natural origin. But no, or few, in vitro tests using other non-mammalian models such as bird have been explored despite their advantages: the embryonic gonads of birds have a high plasticity of development sensitive to estrogen, and sperm production is nearly two times faster than in rodents. Hence, we have established an in vitro culture of germ cells and somatic cells from chicken post-natal testis, and we have evaluated the sensitivity against the endocrine disruptor compound mono-(2-ethylhexyl) phthalate (MEHP) in comparison to previous studies using rodent and human models. After 96 h of exposure in presence of 10 μM MEHP, chicken seminiferous tubules cultures present a structural alteration, a reduction in cell proliferation and in germ cells population. Apoptosis of germ and somatic cells increases in presence of 1 μM MEHP. Furthermore, MEHP does not affect inhibin B and lactate production by Sertoli cells. These results are in accordance with previous studies using rat, mice, or human culture of testicular cells and in similar range of exposures or even better sensitivity for some “end-points” (biological parameters). In conclusion, the establishment of this postnatal testicular cells culture could be considered as an alternative method to in vivo experiments frequently used for evaluating the impact on the terrestrial wildlife species. This method could be also complementary to mammal model due to the limiting number of animals used and its elevated sensitivity.  相似文献   
198.
199.
Living or formerly living organisms are being used to obtain information on the quality of the general health status of our environment by bioindication and biomonitoring methods for many decades. Thus, different roads toward this common scientific goal were developed by a lot of different international research groups. Global cooperation in between various scientific teams throughout the world has produced common ideas, scientific definitions, and highly innovative results of this extremely attractive working field. The transdisciplinary approach of different and multifaceted scientific areas—starting from biology, analytical chemistry, via health physics, up to social and economic issues—have surpassed mental barriers of individual scientists, so that “production” of straightforward common results related to the influence of material and immaterial environmental factors to the well-being of organisms and human life has now reached the forefront of international thinking. For the further sustainable development of our common scientific “hobby” of bioindication and biomonitoring, highest personal energy has to be given by us, being teachers to our students and to convince strategically decision makers as politicians to invest (financially) into the development of education and research of this innovative technique. Young people have to be intensively convinced on the “meaning” of our scientific doing, e.g., by extended forms of education. One example of multilingual education of students on a global scale and perspective is given here, which we started about 3 years ago.  相似文献   
200.
Within the framework of the MYTIOR project in 2009, heavy metals and organic compounds contaminations were assessed in transplanted mussels in 16 different stations along the coasts of Libya. These stations were located at miles offshore industrial/urban sources but in open sea providing original results related to the background contamination rather than linked to a specific coastal source of pollutants. Results indicated mercury (Hg, 0.045–0.066 mg/kg dry weight (dw)), lead (Pb, 0.44–0, 71 mg/kg dw) and copper (Cu, 3.56–4.21 mg/kg dw) were in the same range or at lower value than control for all stations. Chromium (Cr) in Meleta (3.08 mg/kg dw) and Bomba (3.80 mg/kg dw) and Cadmium values in all stations (1.21–2.41 mg/kg dw) were above control. Meleta, stations from the gulf of Syrt and the three eastern stations were the most affected stations by nickel (max at 5.83 mg/kg dw in Syrt) when zinc was in the same range (141–197 mg/kg dw) and above the control (92 mg/kg dw) at all stations. Polycyclic aromatic hydrocarbon (PAH) levels were found in the range of 16.8–42.8 mg/kg (dry weight) indicating low levels along the Libyan coast with acenaphthene and benzo (a, b, k) pyrenes detected mainly in western Libya. The study of PAH ratios indicated a mixed petrogenic/pyrolytic origin. The only polychlorinated biphenyls (PCBs) found in Libya were PCB 101 in one location and PCB 153 in Tripoli, Garrapoli, Syrt, Ras Lanuf and Benghazi (1.2–1.9 μg/kg dw). Insecticides were lower than control in all stations except DDT, only detected in Misratah (3.5 μg/kg dw). Overall, the results indicated a low background contamination and a low pollution extent according to the environmental pressure occurring offshore the Libyan coast.  相似文献   
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