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991.
Loes M.J. Geelen Mark A.J. Huijbregts Henri den Hollander Ad M.J. Ragas Hans. A. van Jaarsveld Dick de Zwart 《Atmospheric environment (Oxford, England : 1994)》2009,43(9):1613-1621
This paper evaluates the ranking of 21 priority air pollutants with three indicator schemes: environmental pressure indicator (EPI), environmental quality indicator (EQI), and human health effect indicator (HEI). The EPI and EQI compare the emissions and concentrations with the target emissions and target concentrations, respectively. The HEI comprehends the steps from cause (i.e. national emissions) to effect (i.e. human health effects), and is the total human health burden, expressed in Disability Adjusted Life Years per year of exposure (DALYs year?1). We estimated a health burden in the Netherlands of 41 × 103 DALYs year?1 caused by Dutch air emissions of PM10 and its precursors in the year 2003. The burden due to 17 carcinogenic substances emitted to air, was much lower (140 DALYs year?1). In contrast, when the same substances were evaluated regarding environmental pressure and environmental quality, carbon tetrachloride (pressure) and benzo[a]pyrene (quality) were of highest importance, whereas the importance of PM10 was substantially lower. This result is remarkable, because for the majority of substances evaluated, the target concentrations and target emissions are based on preventing human health damage. The differences in relevance are explained by the different weighting of interests in the indicators. The HEI is based on concentration–response relations, whereas the EPI and EQI also depend on other, policy-based, principles and on technical feasibility. Therefore, to effectively prioritize emission reduction measures in policy-making, substances should not only be evaluated as to whether emission targets and environmental quality targets are reached, but they should be evaluated regarding their human health impact as well. In this context, the HEI is a suitable indicator to evaluate the human health impact. 相似文献
992.
Gregory L. Brinkman Jana B. Milford James J. Schauer Martin M. Shafer Michael P. Hannigan 《Atmospheric environment (Oxford, England : 1994)》2009,43(12):1972-1981
Personal exposure to fine particulate matter (PM2.5) is due to both indoor and outdoor sources. Contributions of sources to personal exposure can be quite different from those observed at ambient sampling locations. The primary goal of this study was to investigate the effectiveness of using trace organic speciation data to help identify sources influencing PM2.5 exposure concentrations. Sixty-four 24-h PM2.5 samples were obtained on seven different subjects in and around Boulder, CO. The exposure samples were analyzed for PM2.5 mass, elemental and organic carbon, organic tracer compounds, water-soluble metals, ammonia, and nitrate. This study is the first to measure a broad distribution of organic tracer compounds in PM2.5 personal samples. PM2.5 mass exposure concentrations averaged 8.4 μg m?3. Organic carbon was the dominant constituent of the PM2.5 mass. Forty-four organic species and 19 water-soluble metals were quantifiable in more than half of the samples. Fifty-four organic species and 16 water-soluble metals had measurement signal-to-noise ratios larger than two after blank subtraction.The dataset was analyzed by Principal Component Analysis (PCA) to determine the factors that account for the greatest variance. Eight significant factors were identified; each factor was matched to its likely source based primarily on the marker species that loaded the factor. The results were consistent with the expectation that multiple marker species for the same source loaded the same factor. Meat cooking was an important source of variability. The factor that represents meat cooking was highly correlated with organic carbon concentrations (r = 0.84). The correlation between ambient PM2.5 and PM2.5 exposure was relatively weak (r = 0.15). Time participants spent performing various activities was generally not well correlated with PCA factor scores, likely because activity duration does not measure emissions intensity. The PCA results demonstrate that organic tracers can aid in identifying factors that influence personal exposures to PM2.5. 相似文献
993.
McCreanor L Tsuji LJ Wainman BC Martin ID Weber JP 《Environmental monitoring and assessment》2008,140(1-3):211-222
Abandoned military sites in northern North America are relics of the Cold War and sources of polychlorinated biphenyls (PCBs).
In the late 1990s, the Canadian federal and provincial governments began the cleanup of the mid-Canada radar line in Ontario,
Canada. The first site to be remediated was Site 050 (Fort Albany First Nation) in 2001; however, the community remains concerned
that contaminants may have moved prior to, during, and after remediation into the Albany River directly adjacent to Site 050.
Thus, the Albany River was monitored (1999, 2001, 2002) during the remediation process to determine if the cleanup itself
further contaminated the aquatic compartment, using leeches (Haemopis spp.) as bioindicators. Few organochlorines were found in leeches at levels higher than the detection limit, aside from PCBs.
Leech data from the present study indicated that PCB levels were significantly higher near Site 050 than the control site
upstream, indicating point source contamination from Site 050. The temporal trend in leech contaminant data indicated an increase
in PCB contaminant load from 1999 (pre-remediation) to 2001 (immediately post-remediation), but this difference was not statistically
significant due to high variances. Nevertheless, logit log-linear contingency modeling did reveal that immediately after cleanup
(2001), contaminants (CBs 99, 118, 128, 156, 170, 183) in leeches were detected significantly more frequent than expected.
When taken together, leech body burden and frequency of detection data suggest that the remediation process itself further
contaminated the aquatic environment, if only temporarily. Lastly, the removal of the terrestrial source of PCBs during remediation
did remove the source of aquatic contaminants in that body burden of contaminants in leeches were significantly lower a year
after cleanup. 相似文献
994.
Aigars J Müller-Karulis B Martin G Jermakovs V 《Environmental monitoring and assessment》2008,138(1-3):313-326
Two approaches for setting ecological class boundaries, response curves and a simplified mathematical boundary-setting protocol,
were tested for coastal, transitional and open waters in the Gulf of Riga, Baltic Sea. The simplified mathematical boundary-setting
protocol defines acceptable ecological status based on expert judgment by a uniform relative deviation from reference conditions.
In contrast, response curves derive class boundary definitions from observed changes in biological quality elements along
environmental pressure gradients for class boundary definitions. Identification of relevant environmental pressures for the
construction of response curves was based on a conceptual model of eutrophication in the Gulf of Riga. Response curves were
successfully established for summer chlorophyll a and transparency, as well as for macrozoobenthos abundance in the Central
Gulf, macrozoobenthos biotic coefficient in the Southern Gulf, and maximum depth of phytobenthos in the Northern Gulf. In
the Gulf of Riga response curves almost always permitted a larger deviation from reference conditions than the 50% deviation
applied for the simplified mathematical boundary-setting protocol. The case study clearly demonstrated that class boundary
definitions should take into account the sensitivity of the target water body. Also, the class boundaries for different ecological
quality elements were internally more consistent than those derived by the simplified mathematical boundary-setting protocol. 相似文献
995.
Glas B Stenberg B Stenlund H Sunesson AL 《Journal of environmental monitoring : JEM》2008,10(11):1297-1303
This article addresses problems that complicate attempts to compare methods when several factors may be associated with an effect, but it is not known which factors are relevant. Chemicals that may contribute to 'sick building syndrome' (SBS), and thus should be sampled in investigations of SBS, are not currently known. A study was undertaken to compare the utility of three adsorbents (Carbopack B, Chromosorb 106 and Tenax TA) for detecting differences in personal chemical exposure to volatile organic compounds in indoor air, between persons with and without SBS symptoms (cases and controls). On the basis of office workers' responses to a questionnaire, 15 cases and 15 controls were chosen. They simultaneously carried diffusive samplers with adsorbents during a week at work, and the acquired samples were analysed by gas chromatography/mass spectrometry (GC/MS). The adsorbents were then compared in terms of their ability to separate cases and controls in partial least square discriminant analysis (PLS-DA) models. This method of comparison takes into account detected differences in chemical exposure between cases and controls measured with the different adsorbents. Tenax TA gave the best PLS-DA models for separating cases and controls, but a combination of measurements with Tenax TA and Carbopack B gave better PLS-DA models than models based on measurements from either adsorbent alone. Adding measurements from Chromosorb 106 did not improve the results. 相似文献
996.
997.
Mahmoudkhani M Wilewska-Bien M Steenari BM Theliander H 《Waste management (New York, N.Y.)》2008,28(1):133-141
A standard leaching test method (EN 12457-3) was compared with a modified pHstat-column leaching test method with respect to leaching information obtained for aggregates composed of different alkaline solid wastes. In addition to a different experimental set-up, the major dissimilarity between the two test methods was the chemical equilibrium condition, i.e., in the first test the system approaches equilibrium while in the second test the system is far from equilibrium conditions. The leaching trends of sodium, calcium, chloride, sulfate and cadmium were studied. Results showed that these two test methods were comparable in respect to the total amount sodium and sulfate leached. It was also concluded that the two test methods provide different information for the constituents for which dissolution reaction is highly dependent on pH and other experimental conditions, e.g., flow rate. It was found that a batch test can be used in order to investigate the total amount leached, while a modified column-pHstat test generates more detailed results on leaching trends of some constituents. 相似文献
998.
Powlson DS Addiscott TM Benjamin N Cassman KG de Kok TM van Grinsven H L'Hirondel JL Avery AA van Kessel C 《Journal of environmental quality》2008,37(2):291-295
Is nitrate harmful to humans? Are the current limits for nitrate concentration in drinking water justified by science? There is substantial disagreement among scientists over the interpretation of evidence on the issue. There are two main health issues: the linkage between nitrate and (i) infant methaemoglobinaemia, also known as blue baby syndrome, and (ii) cancers of the digestive tract. The evidence for nitrate as a cause of these serious diseases remains controversial. On one hand there is evidence that shows there is no clear association between nitrate in drinking water and the two main health issues with which it has been linked, and there is even evidence emerging of a possible benefit of nitrate in cardiovascular health. There is also evidence of nitrate intake giving protection against infections such as gastroenteritis. Some scientists suggest that there is sufficient evidence for increasing the permitted concentration of nitrate in drinking water without increasing risks to human health. However, subgroups within a population may be more susceptible than others to the adverse health effects of nitrate. Moreover, individuals with increased rates of endogenous formation of carcinogenic N-nitroso compounds are likely to be susceptible to the development of cancers in the digestive system. Given the lack of consensus, there is an urgent need for a comprehensive, independent study to determine whether the current nitrate limit for drinking water is scientifically justified or whether it could safely be raised. 相似文献
999.
Robert Mc Morran Martin F. Price Charles R. Warren 《Journal of Environmental Planning and Management》2008,51(2):177-199
Concepts of wild land have recreational, ecological and cultural dimensions, and place varying emphasis on physical landscape attributes and the perceptions of users. In Scotland, national and NGO policies show reasonable consistency in interpreting and defining ‘wild land’, emphasising the (perception of) lack of current human influence as a key criterion. This research used semi-structured interviews with key individuals and a questionnaire survey of land managers to evaluate concepts and perceptions of wild land in Scotland. Recognising that the conceptual and spatial definition of wild land is a key issue, a new typology is proposed. Weaknesses in the policy framework, as well as key potential threats to, and opportunities associated with, wild landscapes are identified. Management initiatives are fitted to the typology and divided into four management themes. Key recommendations are: (i) that national policy for wild landscapes needs to incorporate criteria, which recognise the multiple values deriving from such areas; and (ii) that future research should combine user group preferences with physical attribute information in determining what constitutes wild landscapes. 相似文献
1000.
Impact of using paper mill sludge for surface-mine reclamation on runoff water quality and plant growth 总被引:1,自引:0,他引:1
Paper mills generate large amounts of solid waste consisting of fibrous cellulose, clay, and lime. Paper mill sludge (PMS) can improve reclamation of surface-coal mines where low pH and organic-carbon levels in the spoil cover material can inhibit revegetation. When applied at high rates, however, PMS may adversely impact the quality of surface runoff. Therefore, we applied PMS at 0, 224, and 672 dry Mg ha(-)(1) to 22.1 x 4.6-m plots at a recently mined site and monitored runoff for a total of 13 mo. The zero-rate plots served as controls and received standard reclamation consisting of mulching with hay and fertilization at planting. Compared to the control plots, PMS reduced runoff fourfold to sixfold and decreased erosion from 47 Mg ha(-1) to <1 Mg ha(-1). Most of the reduction occurred in the 2.5 mo before the plots were planted. Flow-weighted average dissolved oxygen concentrations in runoff from plots at the 224 and 672 Mg ha(-1) rates, however, were much lower (=0.4 vs. 8.2 mg L(-1)) and chemical oxygen demand (COD) was much higher for the 672 Mg ha(-1) rate plots than the control plots during the pre-plant period (7229 vs. 880 mg L(-1)). There were few noteworthy differences in water quality among treatments post-planting, but plant dry-matter yields were greater for the PMS plots than for the controls. The 672 Mg ha(-1) rate did not increase COD or nutrient loads compared to the 224 Mg ha(-1) rate and may have more persistent beneficial effects by increasing soil organic carbon levels and pH to a greater extent. 相似文献