Home About us Contact
|
Home About us Contact | ||
|
|
||
Air Quality (air + quality)
Kinds of Air Quality Selected AbstractsIndoor Air Quality in the 21st Century: Search for ExcellenceINDOOR AIR, Issue 2 2000P. OLE FANGER Abstract Field studies demonstrate that there are substantial numbers of dissatisfied people in many buildings, among them those suffering from sick building syndrome (SBS) symptoms, even though existing standards and guidelines are met. The reason is that the requirements specified in these standards are rather low, allowing a substantial group of people to become dissatisfied and to be adversely affected. A paradigm shift from rather mediocre to excellent indoor environments is foreseen in the 21st century. Based on existing information and on new research results, five principles are suggested as elements behind a new philosophy of excellence: 1) better indoor air quality increases productivity and decreases SBS symptoms; 2) unnecessary indoor pollution sources should be avoided; 3) the air should be served cool and dry to the occupants; 4) "personalized air", i.e. a small amount of clean air, should be served gently, close to the breathing zone of each individual; and 5) individual control of the thermal environment should be provided. These principles of excellence are compatible with energy efficiency and sustainability. [source] The Watershed Deposition Tool: A Tool for Incorporating Atmospheric Deposition in Water-Quality Analyses,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 4 2009Donna B. Schwede Abstract:, A tool for providing the linkage between air and water-quality modeling needed for determining the Total Maximum Daily Load (TMDL) and for analyzing related nonpoint-source impacts on watersheds has been developed. Using gridded output of atmospheric deposition from the Community Multiscale Air Quality (CMAQ) model, the Watershed Deposition Tool (WDT) calculates average per unit area and total deposition to selected watersheds and subwatersheds. CMAQ estimates the wet and dry deposition for all of its gaseous and particulate chemical species, including ozone, sulfur species, nitrogen species, secondary organic aerosols, and hazardous air pollutants at grid scale sizes ranging from 4 to 36 km. An overview of the CMAQ model is provided. The somewhat specialized format of the CMAQ files is not easily imported into standard spatial analysis tools. The WDT provides a graphical user interface that allows users to visualize CMAQ gridded data and perform further analyses on selected watersheds or simply convert CMAQ gridded data to a shapefile for use in other programs. Shapefiles for the 8-digit (cataloging unit) hydrologic unit code polygons for the United States are provided with the WDT; however, other user-supplied closed polygons may be used. An example application of the WDT for assessing the contributions of different source categories to deposition estimates, the contributions of wet and dry deposition to total deposition, and the potential reductions in total nitrogen deposition to the Albemarle-Pamlico basin stemming from future air emissions reductions is used to illustrate the WDT capabilities. [source] Determination of aerial microbiological contamination in scholastic sports environmentsJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2003C. Dacarro Abstract Aims: To assess the microbiological indoor air quality (IAQ) of high school and college gyms during physical training lessons and to evaluate the effective microbiological exposure of students. Methods and Results: Air samples from 11 high school and college gyms of Pavia, Italy were collected. Total bacterial counts, total fungal counts and characterization of fungal taxa were determined. Air quality was evaluated using three microbiological contamination indices: the global index of microbiological contamination per m3 (GIMC per m3), the index of mesophilic bacterial contamination (IMC) and the amplification index (AI). Conclusions: This work testifies that air contamination in indoor gyms is always superior to that of the outdoor environment. Nevertheless, students are exposed to relatively low concentrations of airborne micro-organisms. The highest values of fungal counts and GIMC per m3 (>14 661) were observed between April and October when the central heating systems were switched off. The lowest fungal counts were detected in modern buildings equipped with forced ventilation systems. From qualitative aeromycological studies, 45 fungal taxa were identified, and different potentially allergenic species were isolated. Significance and Impact of the Study: The standardization of air sampling methods and the correct evaluation of aeromicrobiological results allow the classification of indoor air healthiness. The proposed microbiological contamination indices together with the characterization of airborne fungal taxa are useful tools for detailed description of IAQ. [source] Assessment and management of air quality in a mining areaENVIRONMENTAL QUALITY MANAGEMENT, Issue 4 2003S.K. Chaulya First page of article [source] Network bias in air quality monitoring designENVIRONMETRICS, Issue 7 2008Nicola Loperfido Abstract We develop a statistical model for the bias resulting from designing an air quality monitoring network with the aim of finding large values, and then using the data obtained in studies of health effects of air quality. Appropriate conditional distributions are shown to be well-known generalizations of the normal one. Theoretical results are applied to an ozone monitoring network in the state of Washington, USA. Copyright © 2008 John Wiley & Sons, Ltd. [source] Analysis of air quality monitoring networks by functional clusteringENVIRONMETRICS, Issue 7 2008R. Ignaccolo Abstract Air quality monitoring networks are important tools in management and evaluation of air quality. Classifying monitoring stations via homogeneous clusters allows e dentification of similarities in pollution, of representative sites, and of spatial patterns. Instead of summaries by statistical indicators, we propose to consider the air pollutant concentrations as functional data. We then classify using functional cluster analysis, where Partitioning Around Medoids (PAM) algorithm is embedded. The proposed data analysis approach is applied to the air quality monitoring network in Piemonte (Northern Italy); we consider the three more critical pollutants: NO2, PM10, and O3. Copyright © 2008 John Wiley & Sons, Ltd. [source] A high frequency kriging approach for non-stationary environmental processesENVIRONMETRICS, Issue 5 2001Montserrat Fuentes Abstract Emission reductions were mandated in the Clean Air Act Amendments of 1990 with the expectation that they would result in major reductions in the concentrations of atmospherically transported pollutants. The emission reductions are intended to reduce public health risks and to protect sensitive ecosystems. To determine whether the emission reductions are having the intended effect on atmospheric concentrations, monitoring data must be analyzed taking into consideration the spatial structure shown by the data. Maps of pollutant concentrations and fluxes are useful over different geopolitical boundaries, to discover when, where, and to what extent the U.S. Nation's air quality is improving or declining. Since the spatial covariance structure shown by the data changes with location, the standard kriging methodology for spatial interpolation cannot be used because it assumes stationarity of the process. We present a new methodology for spatial interpolation of non-stationary processes. In this method the field is represented locally as a stationary isotropic random field, but the parameters of the stationary random field are allowed to vary across space. A procedure for interpolation is presented that uses an expression for the spectral density at high frequencies. New fitting algorithms are developed using spectral approaches. In cases where the data are distributed exactly or approximately on a lattice, it is argued that spectral approaches have potentially enormous computational benefits compared with maximum likelihood. The methods are extended to interpolation questions using approximate Bayesian approaches to account for parameter uncertainty. We develop applications to obtain the total loading of pollutant concentrations and fluxes over different geo-political boundaries. Copyright © 2001 John Wiley & Sons, Ltd. [source] Seasonal patterns in biomass smoke pollution and the mid 20th-century transition from Aboriginal to European fire management in northern AustraliaGLOBAL ECOLOGY, Issue 2 2007David M. J. S. Bowman ABSTRACT Aim, Globally, most landscape burning occurs in the tropical savanna biome, where fire is a characteristic of the annual dry season. In northern Australia there is uncertainty about how the frequency and timing of dry season fires have changed in the transition from Aboriginal to European fire management. Location, In the tropical eucalypt savannas that surround the city of Darwin in the northwest of the Northern Territory of Australia. Methods, Our study had three parts: (1) we developed a predictive statistical model of mean mass (µg) of particulates 10 µm or less per cubic metre of air (PM10) using visibility and other meteorological data in Darwin during the dry seasons of 2000 and 2004; (2) we tested the model and its application to the broader air shed by (a) matching the prediction of this model to PM10 measurements made in Darwin in 2005, (b) matching the predictions to independent measurements at two locations 20 km to the north and south of Darwin and (c) matching peaks in PM10 to known major fire events in the region (2000,01 dry seasons); and (3) we used the model to explore changes in air quality over the last 50 years, a period that spans the transition from Aboriginal to European land management. Results, We demonstrated that visibility data can be used reliably as a proxy for biomass burning across the largely uncleared tropical savannas inland of Darwin. Validations using independent measurements demonstrated that our predictive model was robust, and geographically and temporally representative of the regional airshed. We used the model to hindcast and found that seasonal air quality has changed since 1955, with a trend to increasing PM10 concentrations in the early dry season. Main conclusions, The results suggest that the transition from Aboriginal to European land management has been associated with an increase in fire activity in the early months of the dry season. [source] Effects on perceived air quality and symptoms of exposure to microbially produced metabolites and compounds emitted from damp building materialsINDOOR AIR, Issue 2 2009A. -S. First page of article [source] Influence of ozone-limonene reactions on perceived air qualityINDOOR AIR, Issue 3 2006G. Tamás First page of article [source] Achieving ,excellent' indoor air quality in commercial offices equipped with air-handling unit , respirable suspended particulateINDOOR AIR, Issue 2 2006K. S. Lam First page of article [source] Relationship between outdoor and indoor air quality in eight French schoolsINDOOR AIR, Issue 1 2005P. Blondeau First page of article [source] The effects of indoor air quality on performance and productivityINDOOR AIR, Issue 2004D. P. Wyon First page of article [source] Ventilation filters and indoor air quality: a review of research from the International Centre for Indoor Environment and EnergyINDOOR AIR, Issue 2004G. Clausen First page of article [source] Organic compounds as indicators of air pollutionINDOOR AIR, Issue 2003L. Mølhave Abstract The most important indoor air pollutants have already been addressed with individual national guidelines or recommendations. However, an international set of guidelines or recommendations for indoor air quality (IAQ) is needed for these pollutants based on general and uniform rules for setting such standards. A major research need exist on the less adverse pollutants before recommendations or guidelines can be established. In the interim period a precaution principle should lead to an ALARA principle for these secondary causalities. It should be noted that volatile organic compound (VOC) as an IAQ problem still is in the end of a phase of ad hoc solutions, in the middle of a research phase and only in the beginning of a regulatory phase. Any final official regulation in this area will have to be tentative and the final regulation must await further research. Total volatile organic compound (TVOC) is an indicator for the presence of VOC indoors. The TVOC indicator can be used in relation to exposure characterization and source identification but for VOCs only, not as an indictor of other pollutants and their health effects. In risk assessment the TVOC indicator can only be used as a screening tool and only for sensory irritation. [source] ESTIMATING THE GENERAL EQUILIBRIUM BENEFITS OF LARGE CHANGES IN SPATIALLY DELINEATED PUBLIC GOODS*INTERNATIONAL ECONOMIC REVIEW, Issue 4 2004Holger Sieg The purpose of this article is to report a new approach for measuring the general equilibrium willingness to pay for large changes in spatially delineated public goods such as air quality. We estimate the parameters of a locational equilibrium model and compute equilibria for alternative scenarios characterizing the availability of public goods within a system of communities. Welfare measures take into consideration the adjustments of households in equilibrium to nonmarginal changes in public goods. The framework is used to analyze willingness to pay for reductions in ozone concentrations in Southern California between 1990 and 1995. [source] A cost-effective operating strategy to reduce energy consumption in a HVAC systemINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 6 2008Nabil Nassif Abstract The operation of the building heating, ventilating, and air conditioning (HVAC) system is a critical activity in terms of optimizing the building's energy consumption, ensuring the occupants' comfort, and preserving air quality. The performance of HVAC systems can be improved through optimized supervisory control strategies. Set points can be adjusted by the optimized supervisor to improve the operating efficiency. This paper presents a cost-effective building operating strategy to reduce energy costs associated with the operation of the HVAC system. The strategy determines the set points of local-loop controllers used in a multi-zone HVAC system. The controller set points include the supply air temperature, the supply duct static pressure, and the chilled water supply temperature. The variation of zone air temperatures around the set point is also considered. The strategy provides proper set points to controllers for minimum energy use while maintaining the required thermal comfort. The proposed technology is computationally simple and suitable for online implementation; it requires access to some data that are already measured and therefore available in most existing building energy management and control systems. The strategy is evaluated for a case study in an existing variable air volume system. The results show that the proposed strategy may be an excellent means of reducing utility costs associated with maintaining or improving indoor environmental conditions. It may reduce energy consumption by about 11% when compared with the actual strategy applied on the investigated existing system. Copyright © 2007 John Wiley & Sons, Ltd. [source] Developing a new cost-efficient control strategy for an actual confectionery plant through the combined exploitation of experimental and numerical analysisINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 6 2003Piero Lunghi Abstract Achieving energy absorption reductions while improving indoor air quality is a major task when designing new air conditioning systems. A cost-effective way to improve energy efficiency without compromising the thermal comfort consists of developing better control. In the present work, an extensive experimental campaign has been coupled with a theoretical analysis with an effective approach. A simulation tool has been implemented and, through its predictions, an efficient control strategy has been developed in a system that resulted in significant energy savings and environmental benefits. Copyright © 2003 John Wiley & Sons, Ltd. [source] Effect of ventilation strategies on air contaminant concentrations and energy consumption in buildingsINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 12 2001Ismail M. Budaiwi Abstract Considering the diversity of indoor contaminant characteristics and generation patterns, finding an appropriate ventilation strategy that can secure acceptable indoor air quality with minimum energy consumption is a challenging task for HVAC system designers and operators. This study theoretically models and investigates the impact of various ventilation strategies on contaminant concentration behaviour and corresponding ventilation cooling energy requirements for a single-zone enclosure. Two types of contaminants are considered; carbon dioxide as an occupancy dependent and formaldehyde, which is independent of occupancy. An airflow model is used to predict space pressure and air leakage rates across the enclosure envelope, and an air quality model is used to predict time-varying contaminant concentrations. In addition, a building energy simulation model is utilized to predict the corresponding ventilation cooling energy requirements under hot climatic conditions. Results from this study show that acceptable contaminant concentrations during occupied periods can be achieved by different ventilation strategies but at substantially different ventilation energy requirements. More than 50 per cent reduction in ventilation energy requirements can be obtained while maintaining acceptable IAQ if proper ventilation strategy is employed. Copyright © 2001 John Wiley & Sons, Ltd. [source] Conflict, Collaboration and Climate Change: Participatory Democracy and Urban Environmental Struggles in Durban, South AfricaINTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, Issue 3 2010ALEX AYLETTArticle first published online: 28 JUN 2010 The South Durban Basin on the eastern coast of South Africa is home to both a large-scale petrochemical industry and a highly mobilized residential community. In a conflict cemented by apartheid-era planning, the community's campaigns to improve local air quality provide a test case for the value of conflict for participatory democratic structures. In the context of the work of the International Panel on Climate Change (IPCC), the South Durban Basin also provides an opportunity to push the boundaries of the established links between participation and the design and implementation of responses to a changing climate. Contributing to one of the main themes of the symposium, this article argues that the focus on collaboration and compromise within studies of governance and participation overlooks both the reality of conflict and its potentially positive effects. Addressing this requires particular attention to how power relationships influence processes of governance, and the role of civil society in balancing the influence of the private sector on the state. It also calls for a better understanding of conflict and collaboration as mutually re-enforcing elements of an ongoing and dynamic political process. Together, the elements of this critique help to build a more nuanced view of participatory urban governance: one that both better describes and may better facilitate the ability of urban populations to collectively, effectively and rapidly respond to the challenges of a changing climate. Résumé Le bassin Sud de Durban, situé sur la côte Est de l'Afrique du Sud, abrite à la fois un vaste secteur pétrochimique et une communauté résidentielle particulièrement mobilisée. Dans une lutte cimentée par un urbanisme datant de l'apartheid, les campagnes communautaires pour améliorer la qualité de l'air local testent la valeur de la lutte en faveur de structures démocratiques participatives. De plus, dans le cadre des travaux du Groupe d'experts intergouvernemental sur l'évolution du climat (GIEC), le bassin Sud de Durban offre une occasion de repousser les limites des liens établis entre la participation, d'une part, et l'élaboration et la mise en ,uvre de réponses au changement climatique, d'autre part. Contribuant à l'un des principaux thèmes du symposium, cet article montre que, compte tenu de leur focalisation sur la collaboration et le compromis, les études sur la gouvernance et la participation négligent la réalité de la lutte autant que ses effets positifs potentiels. Pour ce faire, il examine comment les relations de pouvoir modulent les processus de gouvernance ainsi que le rôle de la société civile visant àéquilibrer l'influence du secteur privé sur l'État. Il convient également de mieux appréhender lutte et collaboration comme des composantes qui se nourrissent mutuellement dans un processus politique permanent et dynamique. Les éléments de cette analyse critique, une fois réunis, aident àélaborer une vision plus nuancée de la gouvernance urbaine participative. Cette vision offre une meilleure description et peut faciliter l'aptitude des populations urbaines à réagir de façon collective, efficace et rapide aux défis du changement climatique. [source] Impact of dietary crude protein and amino acids status on performance and some excreta characteristics of broiler chicks during 10,28 days of ageJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 3 2010N. F. Namroud Summary A study was conducted in a completely randomised design to evaluate the effects of providing almost all important essential amino acids (EAA) in low-crude protein (CP) diets equal to that of higher CP diets in broiler chickens. Also the effects of additional mixture of glycine (Gly) and glutamic acid (Glu) or supplementation of excess EAA to low-CP diets on the live performance and excreta characteristics including pH, moisture, nitrogen, uric acid and ammonia concentration were measured to ascertain the optimum CP concentration for the maximum performance and reduced excreta ammonia concentration. Male, broiler chickens growing from 10 to 28 days of age were fed eight experimental diets. Reducing dietary CP below 19% negatively affected performance. Adding the Gly and Glu mixtures to 17% CP diets improved live performance. Reducing CP to 19% with a normal amino acids status declined N, ammonia, uric acid, moisture and pH of excreta significantly. These findings suggest that diminishing dietary CP from 23% to 19% while maintaining adequate EAA levels during 10,28 days of age results in not only a significant decline in N emission, but also a probable reduction in the NH3 volatilisation because of reduction in pH and moisture. Contrary to expectations, reduction of dietary CP below the minimum level (19%) resulted in more ammonia. All these factors may improve on litter and air quality within the housing facility and reduce the ventilation rate required to emit the elevated ammonia gas concentrations. [source] Determination of aerial microbiological contamination in scholastic sports environmentsJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2003C. Dacarro Abstract Aims: To assess the microbiological indoor air quality (IAQ) of high school and college gyms during physical training lessons and to evaluate the effective microbiological exposure of students. Methods and Results: Air samples from 11 high school and college gyms of Pavia, Italy were collected. Total bacterial counts, total fungal counts and characterization of fungal taxa were determined. Air quality was evaluated using three microbiological contamination indices: the global index of microbiological contamination per m3 (GIMC per m3), the index of mesophilic bacterial contamination (IMC) and the amplification index (AI). Conclusions: This work testifies that air contamination in indoor gyms is always superior to that of the outdoor environment. Nevertheless, students are exposed to relatively low concentrations of airborne micro-organisms. The highest values of fungal counts and GIMC per m3 (>14 661) were observed between April and October when the central heating systems were switched off. The lowest fungal counts were detected in modern buildings equipped with forced ventilation systems. From qualitative aeromycological studies, 45 fungal taxa were identified, and different potentially allergenic species were isolated. Significance and Impact of the Study: The standardization of air sampling methods and the correct evaluation of aeromicrobiological results allow the classification of indoor air healthiness. The proposed microbiological contamination indices together with the characterization of airborne fungal taxa are useful tools for detailed description of IAQ. [source] The Role of Environmental Factors in the Causation of Sudden Death in Infants: Two Cases of Sudden Unexpected Death in Two Unrelated Infants Who Were Cared for by the Same BabysitterJOURNAL OF FORENSIC SCIENCES, Issue 6 2007Bennet I. Omalu M.D., M.P.H. Abstract:, We report two cases of sudden unexpected death in two unrelated African American female infants, 2 months and 4 months old. Both infants were attended to by the same babysitter in the same apartment and died 39 days apart in the same bed and in the same bedroom. The autopsy of the first infant revealed sudden unexplained death in an infant. Toxicologic analysis for carbon monoxide (CO) was not performed because it was not suspected. When the second infant died, investigation into the ambient air quality within the apartment revealed high levels of CO emanating from a poorly ventilated and defective hot water heater, which was located across a hallway from the bedroom where the two babies died. CO saturation levels in the postmortem blood samples of the two babies were elevated and were similar (13% and 14%). Nicotine and cotinine were not detected in the blood sample of the two infants. Cherry-red livor mortis was absent. Acute CO intoxication was determined to be the underlying cause of these two unexpected deaths. These two cases underscore the need to integrate ambient air analysis and postmortem CO analysis as routine components of the comprehensive death investigation of infants who die suddenly and unexpectedly. [source] Higher Education Classroom Fail to Meet Needs of Faculty and StudentsJOURNAL OF INTERIOR DESIGN, Issue 2 2000Lennie Scott-Webber Ph.D. OBJECTIVES: The objectives of this study were (1) to determine differences between faculty and student opinions about university classrooms when the User's Environmental Interaction Framework (UEIF) model's quadrants were considered together, (2) to determine the positive, negative, and different effects between these populations within each UEIF quadrant, and (3) to determine faculty and student use. RESEARCH DESIGN: The User's Environmental Framework (UEIF) guided the research at a large university. This framework has four quadrants: environmental/value dimensions, and behavioral/internal responses, prox-emics concepts, and interactional influences. The study had two parts: (1) a 48-question questionnaire, and (2) behavioral observations surveying both faculty and students (120 subjects) who used 15 general purpose classrooms. ANALYSIS: Stepwise Discriminant Analysis determined which subset of questions best separates student from faculty responses. Canonical Discriminant Analysis further explained relationships. KEY FINDINGS: Return rate was 67% and four observations of each classroom were conducted. Faculty and students agreed on the majority of the items. Subjects felt lighting, air quality, maintenance, equipment, and general comfort were adequate. There was a lack of commitment to the classrooms and subjects had little desire to stay in these rooms. Faculty and students disagreed on 10 questions. Faculty felt the classrooms did not convey a positive experience relating to noise control, seating flexibility, and lacked provision for social interaction. Students found signage inadequate and felt classrooms were uninspiring, nonanticipatory, and lacking symbolic meaning. Behavioral observations supported these concerns. CONCLUSION: Results indicate that general purpose classrooms on this campus do not meet all needs of faculty or students. Problem areas can be addressed through thoughtful knowledge-based interior design solutions. "I have to use a lecture format because I can't change the seating around to include group discussion." "I have to send students out into the hallway if I want to utilize a team approach in my teaching, because the seating is fixed." "I have to move the furniture at the front of the room out of my way as it looks like a used furniture store." "Technology is not integrated, nor easily accessible. It is provided ad hoc, and looks it." [source] Driving less for better air: Impacts of a public information campaignJOURNAL OF POLICY ANALYSIS AND MANAGEMENT, Issue 1 2003Gary T. Henry In the wake of the 1990 amendments to the Clean Air Act, localities across the United States initiated public information campaigns both to raise awareness of threats to air quality and to change behavior related to air pollution by recommending specific behavioral changes in the campaign messages. These campaigns are designed to reduce the health hazards associated with poor air quality and to avoid federal sanctions resulting from the failure to meet air quality standards. As in many other communities across the country, a coalition of government agencies and businesses initiated a public information campaign in the Atlanta metropolitan region to reduce certain targeted behaviors, mainly driving. A two-stage model used to analyze data from a rolling sample survey shows that the centerpiece of the information campaign,air quality alerts,was effective in raising awareness and reducing driving in a segment of the population. When the overall information campaign was moderated by employers' participation in programs to improve air quality, drivers significantly reduced the number of miles they drove and the number of trips they took by car on days when air quality alerts were sounded. Public information campaigns can be successful in increasing awareness, but changing well-established behaviors, such as driving, is likely to require institutional mediation to provide social contexts that support the behavioral change, as well. © 2003 by the Association for Public Policy Analysis and Management. [source] Privatization and Equity in Brazil and RussiaKYKLOS INTERNATIONAL REVIEW OF SOCIAL SCIENCES, Issue 4 2002Werner Baer This paper uses cross,national data from happiness surveys, jointly with data on per capita income and pollution, to examine how self,reported well,being varies with prosperity and environmental conditions. This approach allows us to show that citizens care about prosperity and the environment, and to calculate the trade,off people are willing to make between them. The paper finds that the effect of urban air pollution on subjective well,being shows up as a considerable monetary valuation of improved air quality. For instance, a representative German citizen would need to be given more than 1900$ per year in order to accept the typical urban air pollution level prevailing in Japan. The subjective marginal valuation of air pollution is compared with marginal abatement costs from the literature. [source] Induction of purple sulfur bacterial growth in dairy wastewater lagoons by circulationLETTERS IN APPLIED MICROBIOLOGY, Issue 4 2009J.A. McGarvey Abstract Aims:, To determine whether circulation of dairy wastewater induces the growth of phototrophic purple sulfur bacteria (PSB). Methods and Results:, Two dairy wastewater lagoons that were similar in size, geographic location, number and type of cattle loading the lagoons were chosen. The only obvious visual difference between them was that one was stagnant and the water was brown in colour (Farm 1), and the other was circulated and the water was red in colour because of the presence of PSB that contained carotenoid pigments (Farm 2). Both wastewaters were sampled monthly for 3 months and assayed for PSB and extractable carotenoid pigments (ECP). After this point, circulators were placed in the wastewater lagoon on Farm 1, and samples were taken monthly for 9 months and assayed for PSB and ECP. Before the installation of circulators, no PSB-like 16S rRNA sequences or ECP were observed in the wastewater from Farm 1; however, both were observed in the wastewater from Farm 2. After the installation of circulators, statistically greater levels of PSB and extractable carotenoid pigments were observed in the wastewater from Farm 1. Conclusions:, Circulation enhances the growth of PSB in dairy wastewater. Significance and Impact of this Study:, Because PSB utilize H2S and volatile organic acids (VOA) as an electron source for photosynthesis, and VOA and alcohols as a carbon source for growth, the increase in these bacteria should reduce H2S, volatile organic compounds and alcohol emissions from the lagoons, enhancing the air quality in dairy farming areas. [source] Chinese response to allergy and asthma in Olympic athletesALLERGY, Issue 8 2008J. Li China is going to host the Games of the XXIX Olympiad from 8,24 August 2008 in Beijing. The number of athletes and accompanying individuals expected to arrive at China for the Beijing Olympics is estimated at over 10 000 and among them at least 2 000 (20%) are suspected to suffer from respiratory allergies. It is important to monitor the pollen counts and improve air quality in Beijing because Olympic athletes would be exposed to airborne allergens and pollutants during competitions which could hinder peak performance. The main pollen and spore families in Beijing are Artemisia, Ambrosia, Chenopodiaceae and Gramineae. They can reach around 307 000 grains of pollen/1000 m3 of air in August. Economic development in China is usually linked with worsening of air quality. Due to the adoption of various control measures, the ambient air quality in a number of areas in Beijing has actually improved. The ambient air TSP and SO2 levels in Beijing have been decreasing in the last decade. However, ambient air NOx level has been increasing due to the increased number of motor vehicles. Nevertheless, dedicated medical facilities in Beijing will provide medical services to athletes and delegations from all over the world during the Beijing Olympic Games. [source] Occupational therapy adaptation of the home environment in Sweden for people with asthmaOCCUPATIONAL THERAPY INTERNATIONAL, Issue 4 2002Doctoral Candidate, Margot Frisk Occupational Therapist Abstract The purpose of this study was to evaluate changes of lung function, respiratory symptoms and indoor air quality after reducing allergens and indoor pollutants in the home environment of people with asthma (n = 21). A quasi-experimental pre-/post-test design with one group of participants was implemented. The interventions included removal of wall-to-wall carpets (n = 14) or improvement of indoor air exchange (n = 7). Participants' lung function, symptoms, medication and type-1 allergy were recorded before and after the intervention. The indoor environment was monitored at house calls by an occupational therapist using conventional physical, biological and chemical methods. There was an improvement of lung function evidenced by an increased mean Forced Expiratory Volume (FEV1 %) and a reduction of airway obstruction (reversibility, % of baseline value), which indicate an improved asthmatic condition. Lung function assessed by vital capacity, bronchial hyper-responsiveness, mean of Peak Expiratory Flow, symptom score and medicine consumption did not change significantly. There was a tendency that the amount of airborne dust (p=0.06) was reduced in the indoor environment. Relative humidity, carbon dioxide, formaldehyde and house dust mite levels had decreased after the intervention, but not significantly. Asthma symptoms related to the home environment are probably caused by several factors. When people with asthma suffer from increased symptoms in the home, house calls should be performed routinely. Dust samples from beds and carpets for analysis of allergens give information about exposure, and environmental assessments should be performed before interventions. Occupational therapists can make a valuable contribution in evaluating the home environment and suggesting ergonomic adaptations for individuals with asthma. Copyright © 2002 Whurr Publishers Ltd. [source] Effect of temperature, organic amendment rate and moisture content on the degradation of 1,3-dichloropropene in soil,PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 12 2001Robert S Dungan Abstract 1,3-Dichloropropene (1,3-D), which consists of two isomers, (Z)- and (E)-1,3-D, is considered to be a viable alternative to methyl bromide, but atmospheric emission of 1,3-D is often associated with deterioration of air quality. To minimize environmental impacts of 1,3-D, emission control strategies are in need of investigation. One approach to reduce 1,3-D emissions is to accelerate its degradation by incorporating organic amendments into the soil surface. In this study, we investigated the ability of four organic amendments to enhance the rate of degradation of (Z)- and (E)-1,3-D in a sandy loam soil. Degradation of (Z)- and (E)-1,3-D was well described by first-order kinetics, and rates of degradation for the two isomers were similar. Composted steer manure (SM) was the most reactive of the organic amendments tested. The half-life of both the (Z)- and (E)-isomers in unamended soil at 20,°C was 6.3 days; those in 5% SM-amended soil were 1.8 and 1.9 days, respectively. At 40,°C, the half-life of both isomers in 5% SM-amended soil was 0.5 day. Activation energy values for amended soil at 2, 5 and 10% SM were 56.5, 53.4 and 64.5,kJ,mol,1, respectively. At 20,°C, the contribution of degradation from biological mechanisms was largest in soil amended with SM, but chemical mechanisms still accounted for more than 58% of the (Z)- and (E)-1,3-D degradation. The effect of temperature and amendment rate upon degradation should be considered when describing the fate and transport of 1,3-D isomers in soil. Use of organic soil amendments appears to be a promising method to enhance fumigant degradation and reduce volatile emissions. Published in 2001 for SCI by John Wiley & Sons, Ltd [source] | ||||||||||||||||||||||||||||