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461.
Annoyance produced by air pollution has been suggested as a useful proxy for determining ambient air pollution exposure. However, most of the studies, to date, have focused on nitrogen dioxide and sulphur dioxide, with no work done on volatile organic compounds (VOC). This study is aimed at examining the associations between odour annoyance and VOC in ‘Chemical Valley’, Sarnia, Ontario, Canada. Annoyance scores were extracted from a community health survey (N?=?774), and exposures to VOC were estimated from respondents’ six-digit alphanumeric postal codes using land use regression models. Univariate analyses were used to explore the relationships between odour annoyance and modelled pollutants, whilst multivariate ordinal logistic regression was utilized to examine the determinants of odour annoyance. The results indicate that odour annoyance is significantly associated with modelled benzene, toluene, ethylbenzene, o-xylene and (m?+?p)?xylene (BTEX) pollutants. The findings also show that the determinants of odour annoyance in the context of VOC include gender, number of relatives in the community, perception of air pollution, community satisfaction, medical checkups, ability to cope with daily life demands and general symptoms. When compared, the analysis indicates that Sarnia residents respond to considerably lower BTEX concentrations than the allowable ‘safe’ levels in the province of Ontario. In general, the results exhibit a dose–response gradient with annoyance score increasing with rising modelled pollutant concentrations. The observed relationships suggest that odour annoyance might be a function of true exposure and may serve as a proxy for air quality and ambient air pollution monitoring. However, questionnaire-based odour annoyance scores need to be longitudinally validated across different geographical scales and pollutants if they are to be adopted at the national level.  相似文献   
462.
Considerable research indicates that a wide range of socio-economic factors influence attitudes and perceptions about environmental hazards and risks, and that social trust in those who manage a hazard is strongly correlated to judgements about risks and benefits. We suggest that there are three steps that lead to environmental risk perceptions: acquisition of information, interpretation and synthesis of different pieces of information, and understanding of that information in light of previous knowledge, perceptions, or attitudes. In this study we presented 211 college students in the sciences and non-sciences with ecological and exposure information using text, tables and maps to examine the factors that affect information acquisition and interpretation concerning ecological issues at a fictitious hazardous waste site. Students were allowed about an hour to read the materials and answer questions. The percent of students answering each question correctly varied from 4 to 82%, indicating that some questions were extremely difficult to answer. We attributed these differences to variations in the number of places information was presented (in text, tables, maps, or a combination) and the complexity of the information (how many pieces of information were required to answer the question correctly). The correlation between the number of students answering each question correctly and these combined measures (frequency, complexity) was −0.72. Thus, although there were differences in accuracy concerning ecological information as presented in this study, the major differences were accounted for by how the information was presented, and how much information was required. This suggests that risk communicators should carefully determine which ecological information is critical for the target audience, and ensure that it is presented several times (in different forms). That a lower percentage of people correctly answered questions that required synthesizing several pieces of information suggests that this complexity should be reduced where possible, or that the pieces of information should be tied clearly to the conclusion. Self-declaration of effort and perceptions of safety of the site did not markedly influence the relationship between accuracy, difficulty of finding information, and complexity of information. Other possible confounding variables (i.e., science vs non-science major) only accounted for about 27% of the variation in student’s overall score on ecological questions; age, ethnicity, and gender did not enter as significant variables. We cannot manage environmental hazards with appropriate stakeholder input unless we understand how to present environmental information to achieve a full understanding. Protection of human health and the environment requires that people understand ecological and exposure information, particularly on buffer lands.  相似文献   
463.
Water levels of Lake Sevan (Armenia) were artificially lowered by nearly 20?m between 1949 and 1997. Lowered water levels, combined with increased eutrophication, were associated with seasonally anoxic conditions (lasting 1-4?months) near the bottom of the profundal zone each year during 1976-2004. In addition, the extents of the macrophyte zone and of certain substrate types were severely reduced following drawdown. Maximal depth of occurrence decreased by 2-44?m for at least for 50 species of benthic macroinvertebrates between 1982 and 2004 compared to 1937-1961. Species richness of benthic macroinvertebrates declined from 25 to three species at depths where seasonal anoxia occurred. Total biomass increased by a factor of 10 from the period 1928-1948 to 1976-1979 then declined by a factor of 3 to 4 between 1987 and 2004. Energy flow through detritivores was more than tripled during 1976-2004 compared to 1928-1971, a result of increased plankton primary production. In contrast, energy flow through herbivorous benthic macroinvertebrates decreased by a factor of nearly 5, due to reduced areal coverage of macrophytes. Energy flow through filter feeders did not change over the time period examined, but energy flow through the entire zoobenthos community was nearly tripled. The biomasses of Oligochaeta, Chironomidae, and total zoobenthos showed a delayed response to changes in primary production of 7-9, 2, and 2-4?years, respectively. These patterns may provide a basis to predict results of restoration efforts based on the abundance of the zoobenthos in future years as the level of the lake is restored and water quality improves.  相似文献   
464.
In this paper, we assess the status of the air quality in the Lake Baikal region which is strongly influenced by the presence of anthropogenic pollution sources. We combined the local data, with global databases, remote sensing imagery and modelling tools. This approach allows to inventorise the air-polluting sources and to quantify the air-quality concentration levels in the Lake Baikal region to a reasonable level, despite the fact that local data are scarcely available. In the simulations, we focus on the month of July 2003, as for this period, validation data are available for a number of ground-based measurement stations within the Lake Baikal region.  相似文献   
465.
466.
An explosion in a petrochemical plant in Jilin in the northeast of China on 13 November 2005 was responsible for the discharge of large quantities of benzene and nitrobenzene into Songhua River. This endangered the water supply of Harbin city and influenced the daily life for millions of people. The dispersion-advection equation was solved analytically and numerically and used to simulate the concentration of benzene and nitrobenzene in the Songhua River after the accident. Both solutions gave practically identical results. The main elimination process for both compounds was volatilization. The model results are quite close to the results obtained by measurements at monitoring stations. Arrival time of the pollutant wave, peak concentrations and end of the pollutant wave at Harbin and along the river were predicted successfully. The peak concentrations of nitrobenzene at Harbin were more than 30 times above the permissible limits for drinking water.  相似文献   
467.
The animal husbandry industry is a major emitter of ammonia (NH3), which is a precursor of fine particulate matter (PM2.5)--arguably, the number-one environment-related public health threat facing the nation. The industry is also a major emitter of methane (CH4), which is an important greenhouse gas (GHG). We present an integrated process model of the engineering economics of technologies to reduce NH3 and CH4 emissions at dairy operations in California. Three policy options are explored: PM offset credits for NH3 control, GHG offset credits for CH4 control, and expanded net metering policies to provide revenue for the sale of electricity generated from captured methane (CH4) gas. Individually these policies vary substantially in the economic incentives they provide for farm operators to reduce emissions. We report on initial steps to fully develop the integrated process model that will provide guidance for policy-makers.  相似文献   
468.
Extensive forms of resource use are rarely subject to detailed environmental and social assessment. This paper outlines a potential methodology for assessment of the social impacts of extensive resource use activities based on the Pressure-State-Impact-Response (PSIR) model of integrated indicator development. It then tests this methodology through a case study of changed water flow regimes in Central Queensland's Fitzroy River catchment. While resource degradation associated with interruptions to flow was expected to force all resource users to face higher costs and greater uncertainty, negative social impacts were particularly concentrated among vulnerable groups and downstream industries. Extension of the PSIR framework and methodology proved useful in linking social and biophysical research and would thus appear to offer some potential as a model for incorporating social concerns within natural resource decision making.  相似文献   
469.

Introduction

Each year, there are at least 100,000,000 occupational accidents and 100,000 occupational deaths in the world. In the United States, one of the safest countries in the world in which to work, there were more than 5,400 workplace fatalities and 5.9 million workplace injuries in 2007. The cost to American industry and taxpayers is estimated to be at least $170 billion per year. Further, as illustrated by accidents such as Three Mile Island and Bhopal, industrial accidents potentially impact a much wider sphere than that of the injured worker and his or her employer. As the repercussions of organizational accidents reverberate through organizations and are felt from human resources to accounting, firms are beginning to incorporate messages of safety in their missions and strategies. As firms organize to achieve safer work environments, they are faced with decisions on how to structure their activities in terms of, among other things, size and differentiation.

Method

This paper explores the impact on accident rates of size and differentiation at the corporate and mine levels of mining companies in an effort to create a framework for thinking about organizational accidents from a structural perspective.

Results

The results suggest that larger mines are safer than smaller mines, and that mines with less task diversity are safer than mines with greater task diversity. The results also suggest that at the corporate level, task diversity decreases mine accidents. These results may help mining executives and engineers structure their corporate activities and individual mines more effectively to help reduce accidents.  相似文献   
470.
This paper details the distribution of Cu, Pb and Zn in aquatic systems draining Mount Isa Ag-Cu-Pb-Zn Mine in arid northern Queensland, Australia. Sediment-metal concentrations in the <2mm grain-size fraction adjacent to and downstream of the mine significantly exceed background concentrations (Cu, 159; Pb, 36; Zn, 86 ppm) as well as Australian government sediment quality low trigger guidelines (Cu, 65; Pb, 50; Zn, 200 ppm). Overbank sediments are more contaminated than channel sediments with mean values of Cu, 480; Pb, 540; Zn, 750 ppm. Mean concentrations in cut riverbank samples from the <2mm fraction were Cu, 195; Pb, 724; Zn, 807 ppm. Corresponding <180 microm samples returned concentrations of Cu, 321; Pb, 995; Zn, 1110 ppm. Delivery of contaminants during wet seasons from Mount Isa Mine and historically contaminated riverbanks remains an ongoing issue. The ease of dust entrainment in arid zones means that sediments enriched in toxic concentrations of metals may be widely dispersed and ultimately ingested and absorbed by biota.  相似文献   
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