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1.
The institutional and legislative framework of Swedish environmental protection is presented with special reference to the role of consultation in the policy process. The functions and duties of the National Environment Protection Board, the Franchise Board for Environment Protection, the Environment Advisory Board, and the Product Control Board are outlined. The main thrust of the 1969 Environment Protection Act, the 1972 Hazardous Products Control Act, and the environmental impact assessment requirements of the Planning and Building Legislation is presented. The character of consultation within this framework is also discussed, with reference to the role of public participation and of organized regulated interests. It is found that the main functions of consultation in policy-making are “feeding back on former policy,” “foreseeing future policies,” and “canvassing for consensus.” In the stage of policy clarification, consultation is found to be a means of “catering for compliance” and “creating coherence.” In policy implementation, consultation is an important means of gathering information from parties possibly affected by implementative decisions.  相似文献   

2.
Laboratory studies carried out in sound chambers give experimental support to the theory that fatigue and wakefulness could be influenced by sound and hearing. The tiring effect is more pronounced during exposure to low frequency noise compared to higher frequencies. A tiring effect was observed at lower levels above the hearing perception curve. As expected, when the sound pressure level was raised or the frequency was increased, stress reactions and alertness was a more frequently occurring effect. The laboratory findings were supported by a field study carried out on lorry drivers. The tiring effect was more pronounced when driving lorries generating higher levels of low-frequency noise compared to lorries generating lower levels.  相似文献   

3.
The identification of characteristics of noise-susceptible (S) or noise-resistant (R) individuals is necessary for the development of noise-susceptibility risk profiles. Fifty-six naval aviators, categorized as having either incurred a hearing loss, i.e., hearing threshold levels (HTLs) > 40 dB at 4–8 kHz or retained normal hearing, i.e., HTLs ≤ 25 dB at 125 Hz-8 kHz, after thousands of flight hours were compared along several auditory and non-auditory dimensions. A number of variables occurred differentially in the two groups: Minimal Auditory Intensity Differential (MAID) scores at 2 kHz (p < 0.01) and 4 kHz (p < 0.001); iris pigmentation (blue eyes were over-represented in the S group; p < 0.05); systolic blood pressure (sitting; S group was higher; p < 0.05); calcium, albumin, and LDH levels (higher in the R group; p < 0.05); and present tobacco usage (more S aviators were currently smokers; p < 0.05). The S population also tended (p < 0.10) to exhibit elevated cholesterol and triglyceride levels as well as higher contralateral acoustic reflexes, and to have fewer individuals who had never smoked. Although no classic profile of the S or R individual definitely emerged, results suggested that at least one measurement device (MAID test) may serve as an “early warning” of imminent noise-induced damage. Further research, however, is required to test this possibility.  相似文献   

4.
Air pollution has been associated with an increased incidence of respiratory disease. However, significant differences may exist between air pollution levels measured at conventional fixed monitoring stations and actual levels inhaled by a subject. Furthermore, studies of effects of air pollution might best be done using asthmatics as study subjects, since they have irritable airways. This is a preliminary report of a study using a control and asthmatic group in which effects of air pollution are assessed by sympton and medication diaries and simple pulmonary function tests. Air pollution exposure is measured using a small portable sampler for particulates, SO2 and NO2; these samplers are carried by the subject (“personal”) and are situated inside and outside the home. Levels obtained are compared to data obtained from the same type of sampler located at a fixed monitoring station. Preliminary analysis of the data shows that the levels of pollutants are low and there are significant differences between the four air pollution measurements, with weak correlations among the various measurements. In this preliminary report, change in pulmonary function during the day correlates only with personal NO2 measurements. This suggests the need for estimating air pollution exposure using “personal” samplers, when investigating health effects.  相似文献   

5.
Results from a two-box model for calculation of tracer gas concentrations in rooms are given and consequences of different definitions of “ventilation efficiency” are discussed. Results from three different series of experiments are presented. The first two series were dilution experiments; examples of the results are given and discussed. The third series of tests was performed with one person working at a desk in the test room. Above the person;s head, a tracer gas (N2O) was injected into the convection plume, with as low momentum as possible. Starting with zero concentration, a test continued until steady-state conditions were established for the concentration levels in the different parts of the room. The tests included simulation of summer, autumn/spring, and winter daytime conditions. The results indicate a tendency towards lower tracer gas concentrations in the “breathing zone” when the supply air (typical flow rate equivalent to two air changes per hour) is brought into the room at a low level as compared to a high level close to the ceiling. The exhaust air terminal device in all tests was situated high in the “corridor” wall.  相似文献   

6.
A complete assessment of the health effects of diesel emissions must take into account the possible chemical transformations (and associated biological impacts) of particulate organic matter (POM) due to reactions with the many gaseous copollutants which have now been unambiguously demonstrated to be present in atmospheres burdened by photochemical air pollution. These copollutants include the “trace” species, nitric (HNO3) and nitrous (HONO) acids, the nitrate radical (NO3), formaldehyde (H2CO) and formic acid (HCOOH), as well as the criteria pollutants, ozone (O3) and nitrogen dioxide (NO2). Techniques for establishing the atmospheric concentrations of the trace pollutants (and their spatial and temporal variations) are briefly described, and we present results of investigations into the reactions of polycyclic aromatic hydrocarbons (PAH) coated on filters and exposed to ambient concentrations of O3 and NO2. Environmental health implications of these results are discussed and include the potential for sampling “artifacts” and their possible effects on the correlation (or lack thereof) between ambient PAH levels and urban lung cancer rates, as well as the problems associated with understanding the appropriate POM “dose” to be employed in animal testing and assessments of impacts on human health.  相似文献   

7.
The theory of competing risks cannot be based entirely on the analysis of postmortem pathology data. It is necessary also to know the prevalence and residence times of the diseases in question, separately and jointly, in the living population at risk. It is also necessary to have a conceptual model of the transition process from health to disease, or from one disease state to another, within the organism, so that the formal transition probabilities estimated from epidemiological data can be interpreted in biophysical terms as arising from changes in the physico-chemical state of the organism. This paper offers such a model for transition processes arising from fluctuations of physiological state (for example, lapse into diabetic coma or insulin shock as a result of extreme high or low excursions of the blood sugar level). A Gaussian fluctuation process is postulated, and the transition probability, or incidence rate, is calculated as the frequency with which the state variable fluctuates beyond a specified distance, Λ, from the mean state. An explicit solution is given for the limiting, but biologically reasonable, case that such an excursion is a rare event. In this case, the transition probability varies exponentially for linear displacement of Λ or of the dispersion of fluctuations, σ. If Λ decreases, and/or σ increases, as a linear function of age, this model yields an exponential (Gompertzian) relation of disease incidence to age. Generalization to more than one variable is accomplished by introducing the concept of a mortality potential surface, in which the disease transitions are geometrized as saddle points, or “passes”, on the surface.  相似文献   

8.
The relationship between the odor strength of total air samples and the odor strengths of the constituents was investigated in three field experiments in an office building and a new preschool. The odor strength was scaled by magnitude estimation according to a master scale principle which results in comparable values for the total and the constituent odors. Between 60 and 120 chemical components were detected by GC/FID in the indoor air samples (N = 66). Most (81%) of the detected components in an air sample were odorous, even though most of them were of the low concentrations. By a method of pattern analysis, chemical as well as odor patterns of indoor air were found to be characteristics of different buildings. From the odor patterns (POG), the “odor print” of the outdoor air associated with the buildings was also recognized in the indoor air. Thus, the “odor print” of an air sample is different from its “chemical print”. A model was found that predicts the overall odor strength of an air sample from the number of FID-detected components most frequently reported to have a strong odor.  相似文献   

9.
10.
In the past, most emphasis in planning for and response to an emergency situation has been placed on selected protective measures in the early phase of an emergency to keep the doses received below levels where severe deterministic health effects can be excluded and/or where the risk of stochastic effects in the population is considered “acceptable”. Less emphasis has been placed on the development of comprehensive protection strategies which include considerations of the consequences of all exposure pathways and all phases, e.g. long-term rehabilitation. In its new publication 103, ICRP proposed a coherent conceptual framework for protection in all types of exposure situations including “emergency exposure situations” and “existing exposure situations”. In the context of developing protection strategies for these exposure situations, the Commission recommends that national authorities set reference levels between, typically, 20 mSv and 100 mSv annual effective dose (emergency exposure situation) and 1 mSv and 20 mSv (existing exposure situation). In order to optimise protection strategies, it is necessary to identify the dominant exposure pathways, the timescales over which the dose will be received, and the effectiveness of available protection options. The characteristics of the development and implementation of such protection strategies is described.  相似文献   

11.
Although the “two stage” electrostatic precipitator concept was first developed in 1910, until recently most of their use was confined to in-plant air cleaning. In the last decade, plate type designs have been modified to make them suitable for industrial applications involving organic emissions, most notably in asphalt saturating, plastic curing, food processing, printing, textile finishing, and heat treating industries. However, plate type designs are inadequate in applications where very high loading and/or high particulate content are involved.Tubular design with wider spacing and higher voltages incorporates the best features of both the single stage and two stage type precipitators. These units have been used in molybdenum roasting, zirconium calcining, ammonia scrubbing of oxides of sulfur, meat broiling, foundry exhaust, etc.The paper discusses design parameters, field test data, and operating data on these units. Comparisons with single-stage type precipitators are made wherever applicable. Advantages and disadvantages of two stage precipitators are also discussed.  相似文献   

12.
13.
The opacity and emission performance of two “identical” cold-side precipitators at a power plant utilizing a Western coal source was investigated through an extensive test program. The test program included establishment of outlet emission versus opacity correlations for the two “identical” units, correlation of rapper strategy (frequency and amplitude) with opacity, and correlation of power-off rapping strategy with opacity. Analysis of the test program data demonstrates that the opacity-emission correlations from the two “identical” units can be significantly different. The potential reasons for the differences between the two units are identified and examined in light of the test program data. Strong correlation of opacity with rapping strategy was developed from the test program. Results demonstrate that an automatic power-off rapping technique can significantly enhance precipitator performance on ash from Western coal.  相似文献   

14.
As a guide to the possible effects of a CO2-induced warming on the cryosphere, we review the effects of three warm periods in the past, and out theoretical understanding of fluctuations in mountain glaciers, the Greenland and Antarctic ice sheets, ground ice, sea ice and seasonal snow cover. Between 1890 and 1940 A.D. the glaciated area in Switzerland was reduced by over 25%. In the Hypsithermal, at about 6000 BP, ground ice in Eurasia retreated northward by several hundred kilometres. In the interglacial Stage 5e, at about 120 000 BP, global sea-level rose by over 6 m. Fluctuations of mountain glaciers depend on mesoscale “weather” and on their mechanical response to it. Any melting of the Greenland ice sheet is likely to be slow in human terms. The West Antarctic ice sheet (its base below sea-level) is susceptible to an ungrounding, and such an event may have been the cause of the sea-level rise above. The East Antarctic ice sheet is susceptible to mechanical “surges”, which might be triggered by a warming at its margin. Both an ungrounding and a surge might occupy less than 100 yr, and are potetially the most important ice changes in human terms. Modelling studies suggest that a 5°C warming would remove the Arctic pack ice in summer, and this may be the most significant effect for further climatic change.  相似文献   

15.
Environmental fate of and toxicity data for ammonium ethyl carbamoylphosphonate [fosamine ammonium], N-(phosphonomethyl)glycine [glyphosate], and 3-cyclohexyl-6-(dimethylamino)-1-methyl-1,3,5-triazine-2,4(1H, 3H)-dione [hexazinone] which appear promising for vegetation control in forestry are reviewed. None of the three herbicides is very persistent in soil, with half-lives reported of about 7–10 days for fosamine ammonium, 8–19 weeks for glyphosate, and 1–6 months for hexazinone, depending on soil type and climatic conditions. Degradation in soil is primarily via microbial routes. Whereas hexazinone is a very mobile herbicide (with mobility dependent on soil type), fosamine ammonium and glyphosate are strongly adsorbed and not readily leached in many soil types. Based on bioassay results, the three herbicides exhibit “very low” to “low” toxicity. Fosamine ammonium is not mutagenic and was not teratogenic when fed to pregnant rats at 10,000 ppm. Data on hexazinone indicate no carcinogenic effect in rats, negative in bacterial and mammalian point mutation assays, and not embryotoxic or teratogenic at up to 5000 ppm in diet of rats. The three herbicides have minimum-to-nil effect on soil microorganisms and exhibit little or no potential for bioaccumulation. Limitations of the available data are discussed and suggestions are made for future studies.  相似文献   

16.
With the aim of supporting decision makers to manage contamination in freshwater environments, an innovative expert decision support system (EDSS) was developed. The EDSS was applied in a sediment quality assessment along the Bormida river (NW, Italy) which has been heavily contaminated by an upstream industrial site for more than a century. Sampling sites were classified by means of comparing chemical concentrations with effect-based target values (threshold and probable effect concentrations). The level of each contaminant and the combined toxic pressure were used to rank sites into three categories: (i) uncontaminated (8 sites), (ii) mildly contaminated (4) and (iii) heavily contaminated (19). In heavily contaminated sediments, an environmental risk index (EnvRI) was determined by means of integrating chemical data with ecotoxicological and ecological parameters (triad approach). In addition a sediment risk index (SedRI) was computed from combining chemical and ecotoxicological data. Eight sites exhibited EnvRI values ≥ 0.25, the safety threshold level (range of EnvRI values: 0.14–0.31) whereas SedRI exceeded the safety threshold level at 6 sites (range of SedRI values: 0.16–0.36). At sites classified as mildly contaminated, sublethal biomarkers were integrated with chemical data into a biological vulnerability index (BVI), which exceeded the safety threshold level at one site (BVI value: 0.28). Finally, potential human risk was assessed in selected stations (11 sites) by integrating genotoxicity biomarkers (GTI index falling in the range 0.00–0.53). General conclusions drawn from the EDSS data include: (i) in sites classified as heavily contaminated, only a few exhibited some significant, yet limited, effects on biodiversity; (ii) restrictions in re-using sediments from heavily contaminated sites found little support in ecotoxicological data; (iii) in the majority of the sites classified as mildly contaminated, tested organisms exhibited low response levels; (iv) preliminary results on genotoxicity biomarkers indicate possible negative consequences for humans if exposed to river sediments from target areas.  相似文献   

17.
This paper re-proves and generalizes results by Hardin and Sweet on the time to absorption in certain Markov chains by using a theorem on the time to extinction in multitype branching processes. Renaming “absorption” as “death” and “state immediately before absorption” as “cause of death” makes possible an interpretation in terms of competing risks. This is of very limited value, however, due to the rather severe mathematical restrictions on the Markov chains at hand.  相似文献   

18.
19.
The very significant impact of European legislation (Directive 91/414/EEC) on the authorization of plant protection products is reviewed herein, which has resulted in withdrawal of 704 active substances (AS) out of 889 assessed so far. The list of currently approved 276 AS includes 194 AS “existing” in the market before 1993 and 82 “new” AS introduced during the last 15 years. Results of toxicity characterization of the approved AS are also summarized, utilizing several well-known databases. Although significant data gaps exist for a rather large part of the approved AS, it is found that 84 AS are positive for at least one health effect (after chronic and/or acute exposure) including carcinogenicity, reproductive and neuro-developmental disorders, as well as endocrine disruption. The toxicity characterization results of this study are compared to those of recent assessments by other organizations (KemI, the Swedish Chemicals Agency, and the Pesticide Safety Directorate of the UK), where interpretation and use is made of AS “cut-off” criteria foreseen in new EU legislation. These studies report a comparatively smaller AS number with positive toxicity characterization. The possibility of some additional AS withdrawal in the near future, combined with the rather small rate of new AS introduction (approx. 5 per year) suggest that the list of approved AS over the next 10–15 years may not change very drastically. Consideration of the above trends is necessary and instructive in evaluating results of existing health impact assessment (HIA) studies, as well as in planning new ones. Due to the very drastic change in the number and type of marketed AS, that took place within the past 8–9 years, it is suggested that new HIA studies (based on epidemiological data after year 2000) should focus on a rather short time frame and, therefore, on appropriate cohort groups, e.g. young children. For the same reason, results of epidemiological studies of the past (involving banned AS) should be carefully interpreted and used with caution.  相似文献   

20.
The decrease of foliar activity in vegetation after its initial contamination by foliar deposition is termed “field loss” (Chamberlain, 1970). This work investigated further laboratory data concerning field loss of 134Cs, 137Cs, 85Sr, 133Ba and 123mTe deposited on grassland (Madoz-Escande et al., 2005). Treatments consisted in rainfall scenarios cumulating 14 mm per week, combining two levels of intensity (8 or 30 mm/h) and two levels of frequency/precocity (late once or early twice-a-week). The time course of field loss was monitored in the edible tissues which were sampled by mowing between the rainfalls. Data were analyzed with an offset exponential loss model which is applicable to chronic contamination and is consistent with approaches adopted in radiological assessment models. Its parameters were estimated by the maximum-likelihood method, and their accuracy was determined by nonparametric boostrap. Radionuclide and rainfall conditions significantly affected the estimated rate (λ1) and extent (A1) of field loss. Field loss rate (λ1) and nonentrainable fraction (1 − A1) varied by a factor 1.5–3. Cesium was very mobile but persistent. On the contrary Tellerium was found less labile, but eventually was almost completely eliminated. Strontium and Barium had intermediate behaviors. Field loss was more efficient for moderate late once-a-week rainfalls (8 mm/h). Higher rainfall intensity reduced more the radionuclides losses than higher rainfall frequency/precocity. This paper reports statistically relevant effects that should be considered for more realistic assessments.  相似文献   

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