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231.
Use of fipronil {5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-trifluoromethyl)sulfinyl]-1H-pyrazole-3-carbonitrile CAS 120068-37-3} topical pet products on dogs and cats introduces low level residues into residences. Distribution and fate studies of fipronil on pets and in residences were performed to evaluate potential determinants of human exposure. Fipronil, desulfinyl fipronil, fipronil sulfone and fipronil sulfide were measured on hair clippings and brushed hair. The derivatives usually represented <10% of fipronil applied. Cotton gloves worn over impervious nitrile gloves, cotton cloths placed indoors in locations frequented by pets, and cotton socks worn by residents as direct dosimeters collected fipronil and its derivatives listed above in low amounts during 4-week study periods. Subsequent acid hydrolysis urine biomonitoring did not reveal significant excretion of biomarkers at ppb levels. The human exposure potential of fipronil is low relative to levels of health concern.  相似文献   
232.
Volatile organic compounds can contribute to the failure of electronic equipment in both switching offices and data centers. They can also be useful indicators of ventilation needs. Only within the past decade have ambient concentrations of volatile organics been measured routinely. In standard sampling approach, a pump is used to pull a known volume of air through an adsorbent. This study examines a sampling procedure that does not use a pump, but instead depends on molecular diffusion for eventual contact between the vapor phase compounds and the charcoal sorbent (passive sampling). The technique is both simpler and less expensive than active sampling with a pump. This method has been validated for low-level sampling over extended time intervals. This study demonstrates that collected amounts vary linearly with airborne concentrations for sampling intervals in excess of four weeks: even after eight weeks of sampling at typical ambient concentrations, the amount of material collected does not approach the capacity of the sorbent. The method is applicable for concentrations spanning six orders of magnitude; reproducibility averages 13 percent of the mean value; and the sensitivity is excellent (0.06 μg/m3 or roughly 0.015 ppbv for a compound with a molecular weight of 100). The procedure has already been used successfully to monitor indoor air quality at almost a dozen telephone office and data center sites.  相似文献   
233.
ABSTRACT

We conducted a multi-pollutant exposure study in Baltimore, MD, in which 15 non-smoking older adult subjects (>64 years old) wore a multi-pollutant sampler for 12 days during the summer of 1998 and the winter of 1999. The sampler measured simultaneous 24-hr integrated personal exposures to PM25, PM10, SO4 2-, O3, NO2, SO2, and exhaust-related VOCs.

Results of this study showed that longitudinal associations between ambient PM2.5 concentrations and corresponding personal exposures tended to be high in the summer (median Spearman's r = 0.74) and low in the winter (median Spearman's r = 0.25). Indoor ventilation was an important determinant of personal PM2.5 exposures and resulting personal-ambient associations. Associations between personal PM25 exposures and corresponding ambient concentrations were strongest for well-ventilated indoor environments and decreased with ventilation. This decrease was attributed to the increasing influence of indoor PM2 5 sources. Evidence for this was provided by SO4 2-measurements, which can be thought of as a tracer for ambient PM25. For SO4 2-, personal-ambient associations were strong even in poorly ventilated indoor environments, suggesting that personal exposures to PM2.5 of ambient origin are strongly associated with corresponding ambient concentrations. The results also indicated that the contribution of indoor PM2.5 sources to personal PM2.5 exposures was lowest when individuals spent the majority of their time in well-ventilated indoor environments.

Results also indicate that the potential for confounding by PM2.5 co-pollutants is limited, despite significant correlations among ambient pollutant concentrations. In contrast to ambient concentrations, PM2.5 exposures were not significantly correlated with personal exposures to PM2.5-10, PM2.5 of non-ambient origin, O3, NO2, and SO2. Since a confounder must be associated with the exposure of interest, these results provide evidence that the effects observed in the PM2.5 epidemiologic studies are unlikely to be due to confounding by the PM2.5 co-pollutants measured in this study.  相似文献   
234.
Collaborative problem solving has increasingly become important in the face of the complexities in the management of resources, including protected areas. The strategy undertaken by Girringun Aboriginal Corporation in north tropical Queensland, Australia, for developing co-management demonstrates the potential for a problem solving approach involving sequential initiatives, as an alternative to the more familiar negotiated agreements for co-management. Our longitudinal case study focuses on the development of indigenous ranger units as a strategic mechanism for the involvement of traditional owners in managing their country in collaboration with government and other interested parties. This was followed by Australia's first traditional use of marine resources agreement, and development of a multi-jurisdictional, land to sea, indigenous protected area. In using a relationship building approach to develop regional scale co-management, Girringun has been strengthening its capabilities as collaborator and regional service provider, thus, bringing customary decision-making structures into play to 'care for country'. From this evolving process we have identified the key components of a relationship building strategy, 'the pillars of co-management'. This approach includes learning-by-doing, the building of respect and rapport, sorting out responsibilities, practical engagement, and capacity-building.  相似文献   
235.

Agricultural systems have become increasingly industrialized and mechanized, relying on machinery and chemical inputs, rather than people and natural processes, to increase yields of food. The trend towards an increasingly globalised food system encourages unsustainable transportation of food around the world. Agricultural intensification and the globalisation of the agrofood chain has resulted in adverse environmental, social and economic consequences impeding moves towards sustainability. Organic farming can overcome many of the environmental problems associated with agricultural intensification. However, it does not have the potential to fully address the social and economic problems caused by the globalisation of the food system. Organic farming must be combined with local and regional sourcing of food products, for instance through forms of direct marketing of organic produce. Direct marketing schemes such as farmers' markets, food box delivery schemes and community-supported agriculture are all projects which, if managed with sustainability as the prime objective, have the potential to move towards a more socially, environmentally and economically sustainable agrofood system.  相似文献   
236.
Humanitarian food assistance aims to meet short‐term emergency needs, yet often it is sustained over many years and develops its own systems and infrastructure that interact with local governance and local communities. This paper explores the links between participation and local governance, as well as the implications for exclusion of certain groups, the dignity of those involved, and protection issues. The paper proposes a framework for reviewing the governance functions and capacities of local Food Relief Committees, based on the following criteria: accountability; gender equity; legitimacy and authority; representativeness; responsiveness; and transparency. A case study of the Darfur region reviews how local governance evolves as a result of both the wider conflict and of adapting to the international humanitarian system, itself a form of governance. The paper concludes by proposing three strategies for enhancing participation and applying lessons learned: improved analysis of participation; linking programming strategies and protection; and taking account of governance functions and capacities.  相似文献   
237.
Conservation of migratory species exhibiting wide-ranging and multidimensional behaviors is challenged by management efforts that only utilize horizontal movements or produce static spatial–temporal products. For the deep-diving, critically endangered eastern Pacific leatherback turtle, tools that predict where turtles have high risks of fisheries interactions are urgently needed to prevent further population decline. We incorporated horizontal–vertical movement model results with spatial–temporal kernel density estimates and threat data (gear-specific fishing) to develop monthly maps of spatial risk. Specifically, we applied multistate hidden Markov models to a biotelemetry data set (n = 28 leatherback tracks, 2004–2007). Tracks with dive information were used to characterize turtle behavior as belonging to 1 of 3 states (transiting, residential with mixed diving, and residential with deep diving). Recent fishing effort data from Global Fishing Watch were integrated with predicted behaviors and monthly space-use estimates to create maps of relative risk of turtle–fisheries interactions. Drifting (pelagic) longline fishing gear had the highest average monthly fishing effort in the study region, and risk indices showed this gear to also have the greatest potential for high-risk interactions with turtles in a residential, deep-diving behavioral state. Monthly relative risk surfaces for all gears and behaviors were added to South Pacific TurtleWatch (SPTW) ( https://www.upwell.org/sptw ), a dynamic management tool for this leatherback population. These modifications will refine SPTW's capability to provide important predictions of potential high-risk bycatch areas for turtles undertaking specific behaviors. Our results demonstrate how multidimensional movement data, spatial–temporal density estimates, and threat data can be used to create a unique conservation tool. These methods serve as a framework for incorporating behavior into similar tools for other aquatic, aerial, and terrestrial taxa with multidimensional movement behaviors.  相似文献   
238.
A formal model for consensus and negotiation in environmental management   总被引:8,自引:0,他引:8  
Environmental management decisions typically lie at the interface of science and public policy. Consequently, these decisions involve a number of stakeholders with competing agendas and vested interests in the ultimate decision. In such cases, it is appropriate to adopt formal methods for consensus building to ensure transparent and repeatable decisions. In this paper, we use an environmental management case study to demonstrate the utility of a mathematical consensus convergence model in aggregating values (or weights) across groups. Consensus models are applicable when all parties agree to negotiate in order to resolve conflict. The advantage of this method is that it does not require that all members of the group reach agreement, often an impossible task in group decision making. Instead, it uses philosophical foundations in consensus building to aggregate group members' values in a way that guarantees convergence towards a single consensual value that summarizes the group position. We highlight current problems with ad hoc consensus and negotiation methods, provide justification for the adoption of formal consensus convergence models and compare the consensus convergence model with currently used methods for aggregating values across a group in a decision making context. The model provides a simple and transparent decision support tool for group decision making that is straightforward to implement.  相似文献   
239.
The persistence of glyphosate and its primary metabolite AMPA (aminomethylphosphonic acid) was monitored in two areas in Southern Greece (Peza, Crete and Chora Trifilias, Peloponnese) with a known history of glyphosate use, and the levels of residues were linked to spray operators’ activities in the respective areas. A total of 170 samples were collected and analysed from both areas during a 3-year monitoring study. A new method (Impact Assessment Procedure - IAP) designed to assess potential impacts to the environment caused by growers’ activities, was utilised in the explanation of the results. The level of residues was compared to the predicted environmental concentrations in soil. The ratio of the measured concentrations to the predicted environmental concentrations (MCs/PECs) was >?1 in Chora the first 2 years of sampling and <?1 in the third year, whilst the MCs/PECs ratio was <?1 in Peza, throughout the whole monitoring period. The compliance to the instructions for best handling practices, which operators received during the monitoring period, was reflected in the amount of residues and the MCs/PECs ratio in the second and especially the third sampling year. Differences in the level of residues between areas as well as sampling sites of the same area were identified. AMPA persisted longer than the parent compound glyphosate in both areas.  相似文献   
240.
公用事业已经对环境质量产生重要的影响,特别是在市区.初看起来,放宽限制或公用事业的私有化似乎提供不了任何环境效益.然而,如果在一个合适的管理法律体制内发生这样一个变化,结果实际上是提高了人们对可持续发展的注意.关于这一点,给出了一个关于改善公路运输的可持续发展性机会的实例研究.  相似文献   
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