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The development of a sensitive method to study volatile organic compounds in gaseous emissions of lung cancer cell linesMaroly, Anupam 29 August 2005 (has links)
The ultimate objective of this research was to develop a low cost, reliable system that
would lead to early detection of lung cancer. Tests involved the quantitation of gaseous
metabolic emissions from immortalized lung cancer cell lines in order to correlate the
chemical markers to be of cancerous origin. The specific aims of the project were the
study of gas emissions in selected cancer cell lines and identification of volatile organic
compounds (VOCs) in them.
Disadvantages of earlier studies were that the measurements were not real time or state
specific so that molecular identification was often inconclusive. Furthermore the methods
of study used in the past were not quantitative, which limited their practicality for
medical applications. We felt the need to prove or disprove these earlier results using a
new technique.
The method we proposed is different and unique when compared to previous methods
because cell lines have not been studied extensively for cancer markers. We have studied
cancer cell lines which are adherent, immortalized cultures originating from primary
tumors obtained from patients with no prior treatment for lung cancer.
We have used an alternative method for the spectrometric analysis and quantitation of the
selected chemical markers. The pre-concentration method involved a Purge and Trap
unit with a thermal desorber where the vapor concentration was enhanced. The
concentrated head space gases were analyzed using a Gas Chromatograph ?? Mass
Spectrometer setup. This setup eliminated the bulky apparatus used in earlier studies. It is
simpler in design and more comprehensive so that external factors such as patient??s diet,
habitat and lifestyle do not contribute to our study of recognition of cancer markers.
Based on the results obtained in the above experiments, a more comprehensive,
inexpensive study of lung cancer related markers could be made.
The first section, after giving an introduction to lung cancer, goes on to explain the
background work done by other researchers on cancer. The third section gives a detailed
explanation of the experimental setup. This is followed by all the tests conducted with
corresponding results. The final section deals with the conclusions drawn from all
experiments.
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Oxidation characteristics of fluorine-, nitrogen-, and sulfur-containing organic compounds by UV/O3Chang, Ken-Lin 10 September 2007 (has links)
DMSO (dimethyl sulfoxide) is a liquid with a high boiling point (189 oC) that has been extensively utilized in various industries owing to its ability to dissolve various organic and inorganic compounds. DMSO is increasingly being adopted as a detergent or a photo-resistant stripping solvent in manufacturing semiconductors and liquid crystal displays (LCD). Therefore, DMSO is now a major component of wastewater. The biological treatment of DMSO-containing wastewater generates noxious DMS (dimethyl sulfide) and other compounds that may cause odor problems. Also having a high water solubility and a moderate boiling point (110 oC), tetrafluoro propanol (TFP) has been extensively applied in the manufacture of CD-R and DVD-R, due to its ability to dissolve organic dyes. The spin coating process produces a large amount of wastewater containing TFP. No reports have been written on the biodegradability of TFP to the authors¡¦ knowledge. Additionally, HMDS (hexamethyldisilazane) has been extensively used in life science microscopy and material science. For instance, the semiconductor industry employs HMDS to promote the adhesion of photo-resistant material to oxide(s). HMDS is classified as a carcinogen, and has an ammonia odor. Condensing incinerators have been found to be unsuitable for treating HMDS-containing waste gases, because of the formation of silicon dioxide, which blocks porous adsorbents. Biological treatment also appears to be unpromising due to its low water solubility and limited biodegradability.
This investigation evaluates the feasibility, effectiveness and oxidation characteristics of aqueous DMSO, TFP and gaseous HMDS (hexamethyldisilazane) by UV/O3 processes. A reactor made entirely of acrylic plastic with an effective volume of 10 L was employed for the reactions. The tested VOCs concentrations were adjusted to 400¡V890mg/L and 772¡V887 mg/L for DMSO and TFP, respectively, and the gas (ozone-enriched air) flow rate was controlled at 3L/min. The effects of various solution pH values (acidic, alkaline, uncontrolled), solution temperatures (26 oC, 37 oC, 48 oC and 60 oC), and UV wavelengths (254 nm and 185+254 nm) on the removal of tested VOCs were studied . Additionally, the operation costs of treating DMSO and TFP by UV/O3 were estimated.
Experimental results demonstrate that acidic conditions (pH = 3.6) favored the degradation of DMSO, and that the removal efficiency could reach 95% at a volumetric UV intensity P/V of 2.25 W/L and a reaction time of 120 min. However, alkaline conditions (pH = 9.5) favored the decomposition of TFP, with the removal efficiency reaching 95% at P/V = 2.5 W/L and a reaction time of 60 min. Both DMSO and TFP exhibited zero-order degradation kinetics when sufficient ozone was supplied. Raising the oxidation temperature did not increase the UV/O3 oxidation of TFP in the tested concentration and temperature ranges. Operation costs of the UV/O3 per unit volume of wastewater with DMSO or TFP are comparable to those of the methods described in the literature.
For the gaseous HMDS oxidation, two batch reactors with effective volumes of 1.2 and 5.8 L were used employed with the decomposition occurred under UV (185+254 nm) irradiation and UV (254 nm)/O3 processes. Tests were performed with initial HMDS concentrations of 32¡V41mg/m3 under various initial ozone dosages (O3 (mg)/HMDS (mg) =1¡V5), atmospheres (N2, O2, and air), temperatures (28 oC, 46 oC, 65 oC and 80 oC), relative humilities (20%, 50%, 65% and 99%) and volumetric UV power inputs (0.87 W/L, 1.74 W/L, 4.07 W/L and 8.16 W/L) to assess their effects on the HMDS degradation rate.
Results of this study demonstrate that the decomposition rates for the UV (185+254 nm) irradiation exceeded those for the UV (254 nm)/O3 process for all conditions. UV (185+254 nm) decompositions of HMDS displayed apparent first-order kinetics. A process with irradiation of UV (185+254 nm) to HMDS in air saturated with water at temperatures of 46¡V80 oC favors the HMDS degradation. With the above conditions and a P/V of around 8 W/L, k≈ 0.20 s−1, and over 90% of the initial HMDS was degraded in a time of 12s. The main mechanisms for the HMDS in wet air streams irradiated with UV (185+254 nm) were found to be caused by OH free radical oxidation produced from photolysis of water or O (1D) produced from photolysis of oxygen. Economic evaluation factors of UV (185+254 nm) and UV (254 nm)/O3 processes at various UV power inputs were also estimated.
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Treatment of Volatile Organic Compounds by a Regenerative Catalytic OxidizerLin, Chien-hung 24 July 2009 (has links)
Abstract
Isopropyl alcohol¡]IPA¡^and toluene are extensively used in industry as solvents. They are all highly toxic to animals and humans. Accordingly, IPA and toluene are strongly associated with problems of VOCs. In first step catalytic incineration was adopted to decompose IPA and toluene in laboratory, and the second step for a pilot-scale regenerative catalytic oxidizer ¡]RCO¡^were adopted to decompose mixture VOCs in real soil herein.
The screening test of catalytic activity and the influences of the operational parameters on IPA and toluene removal efficiencies were widely discussed through catalytic incinerations of IPA and toluene in laboratory. The more effective and cheaper catalysts through above discussions of catalytic incineration were selected. And they were utilized in an pilot scale RCO as follows to investigate their performance in VOCs oxidation and RCO operations in THC removal of contamination soils. The achievements of this study are summarized as follows:
¡]1¡^Cu/Mn and Cu/Co gravel catalytic incinerations of isopropyl alcohol
The results demonstrated that 10 wt% Cu0.6Co0.4 catalyst was the most effective because the CO2 yield reached 95 % under the following operating conditions; a temperature of 425oC, an inlet IPA concentration of 2500 ppm, an oxygen concentration of 21%, and a space velocity of 13500 hr-1. Additionally, the stability test results indicated that the 10 wt% Cu0.6Co0.4 catalyst exhibited excellent stability at both low and high conversion of IPA.
¡]2¡^20% Cu/Mn aluminum oxide catalytic incinerations of toluene
The conversion for toluene reached 95% when the Cu/Mn catalyst was used with a metal ratio of 1:1 and 20% loading at 350¢XC, an influent toluene concentration of 1000 ppm, oxygen concentration of 21%, a space velocity of 12000 hr-1, and relative humidity of 26%. The long-term test was proceeded for seven days at a constant influent toluene concentration of 1000 ppm, constant oxygen concentration of 21%, constant space velocity of 12000 hr-1 and constant relative humidity of 26%. The SEM results indicated the Cu/Mn catalyst was quite stable at 350¢J.
¡]3¡^RCO testing for a copper/manganese catalyst of gaseous toluene
The Cu/Mn (20wt%) catalyst was selected as the best one, because it converted 95% of the toluene at 400¢J. The results also indicating that the Cu/Mn catalyst was quite stable at 400¢J.
(4) RTO treatment of VOCs with SVE system
The conversion for VOCs reached 80% at 900¢XC, an influent VOCs concentration of 450-2000 ppm and a gas flow rate of 0.5 m3/min.The Thermal Recovery Efficiency¡]TRE¡^was approximately 86-90% in a RTO operated at 800-900¢J.
(5)RCO treatment of VOCs with SVE system¡]10 wt% Cu0.6Co0.4 gravel catalyst¡^
The 10 wt% Cu0.6Co0.4 gravel catalyst was the poverty active, because it converted 65% of the VOCs by SVE system operated at 650¢J.
(6)RCO treatment of VOCs with SVE system¡]20% Cu/Mn aluminum oxide catalytst¡^
The 20% Cu/Mn aluminum oxide catalytic was the best choice, because it converted 95% of the VOCs at 650¢J, an influent VOCs concentration of 450-10000 ppm and a gas flow rate of 0.5-1.5 m3/min. The SEM results indicated that the conversion of VOCs decay did not clearly vary at 650¢J, also indicating that the Cu/Mn catalyst selected was quite stable. The TRE was approximately 90% in a RCO¡]20% Cu/Mn aluminum oxide catalytic¡^operated at 650¢J.
(7)RCO treatment of VOCs with SVE system¡]20% Cu/Mn gravel catalytst¡^
The 20% Cu/Mn gravel catalytst was the best selection , because it converted 95% of the VOCs at 600¢J, an influent VOCs concentration of 450-10000 ppm and a gas flow rate of 0.5-1.5 m3/min. The SEM results indicated that the conversion of VOCs decay did not clearly vary at 600¢J, also indicating that the Cu/Mn catalyst selected was quite stable. The TRE was approximately 90% in a RCO¡]20% Cu/Mn gravel catalytic¡^operated at 600¢J.
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Evaluating the design of emissions trading programs using air quality modelsThompson, Tammy Marie 13 August 2012 (has links)
In order to meet the US EPA's National Ambient Air Quality Standards as set under the provisions of the Clean Air Act, states and regions throughout the United States are designing cap and trade programs aimed at reducing the emissions of the two dominant precursors for ozone, nitrogen oxides (NOx) and Volatile Organic Compounds (VOCs). While emission cap and trade programs are becoming more common, relatively few analyses have examined the air quality implications of moving emissions from one location to another (due to trading of emissions between facilities), from one sector to another (due to the use of technologies such as Plug-in Electric Hybrid Vehicles - PHEVs), and changing the temporal distribution of emissions (through emissions trading among facilities with different temporal profiles). This thesis will examine, in detail, the air quality implications of two emission cap and trade programs. The first program is a NOx trading program that covers Electricity Generating Units (EGUs) in the Northeastern United States. Results show that refining the temporal limits on this cap and trade program, by charging facilities more to emit NOx on days when ozone is most likely to form, has the potential to significantly reduce NOx emissions and ozone concentrations. Additionally, this research also shows that, for this region, the spatial redistribution of NOx emissions due to trading leads to greater ozone reductions than similar amounts of NOx emission reductions applied evenly across all facilities. Analyses also indicate that displacing emissions from the on-road mobile sector (vehicles) to the EGU sector through the use of PHEVs decreases ozone in most areas, but some highly localized areas show increases in ozone concentration. The second trading program examined in this thesis is limited to Houston, Texas, where a VOC trading program is focused on a sub-set of four Highly Reactive Volatile Organic Compounds (HRVOCs), which have been identified as having substantial ozone formation potential. Work presented in this thesis examined whether this trading program, in its current form or in an expanded form, could lead to air pollution hot spots, due to spatial reallocation of emissions. Results show that the program as currently designed is unlikely to lead to ozone hot spots, so no further spatial limitations are required for this program. Expanding the trading to include Other VOCs, fugitive emissions and chlorine emissions, based on reactivity weighted trading, is also unlikely to lead to the formation of ozone hot spots, and could create more flexibility in a trading market that is currently not very active. Based on these air quality modeling results, policy suggestions are provided that may increase participation in the trading market. These case studies demonstrate that use of detailed air analyses can provide improved designs for increasingly popular emission cap and trade programs, with improved understanding of the impacts of modifying spatial and temporal distributions of emissions. / text
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New Strategies for the Detection of <i>Fusarium</i> Infection and Mycotoxin Contamination of Cereals and MaizeBecker, Eva-Maria 14 May 2013 (has links)
Phytopathogene <i>Fusarium</i> spp.treten weltweit in landwirtschaftlichen Kulturen auf und führen häufig zur Ertragsreduktion, Verschlechterung der Produktqualität sowie Kontaminationen der Erntegüter mit toxischen Sekundärmetaboliten, sog. Mykotoxinen. Die durch <i>Fusarium spp.</i> hervorgerufene partielle Taubährigkeit (FHB) des Weizens und anderer Getreidearten sowie die <i>Fusarium</i> Kolbenfäule an Mais sind aus ökonomischer Sicht von besonderer Bedeutung. Im Rahmen dieser Arbeit wurde die Verwendung von volatilen organischen Verbindungen (VOCs) zur Detektion von Fusariosen an Sommerweizen und Hybridmais unter Gewächshausbedingungen untersucht. Maiskolben wurden mit <i>F. graminearum</i>, <i>F. verticillioides</i> und <i>F. subglutinans</i> infiziert, während Weizenähren mit Sporensuspensionen von <i>F. graminearum</i>, <i>F. avenaceum</i> und <i>F. poae</i> inokuliert wurden. Auch Mischinfektionen wurden durchgeführt. Für die Sammlung der VOCs wurde ein statisches Verfahren (Festphasenmikroextraktion, SPME) sowie ein dynamisches Verfahren (open-loop stripping, OLS) eingesetzt. Die Analyse erfolgte in beiden Fällen mittels GC-MS. Ein nichtparametrischer Test (Kruskal-Wallis) wurde zur Identifikation von spezifischen volatilen Markern herangezogen. Auf diese Weise konnte an Mais ein Set aus 27 volatilen Biomarkern für die Infektion mit <i>Fusarium</i> spp. ermittelt werden. Die Kombination der VOCs ermöglichte hier die Unterscheidung zwischen Infektionen mit <i>F. graminearum</i> und <i>F. verticillioides</i>. An Weizen konnte ein Set aus 13 charakteristischen VOCs für den <i>Fusarium</i> Befall ermittelt werden. Die selektierten volatilen Marker beinhalteten sowohl einfache Moleküle mit 5 bis 8 Kohlenstoffatomen (C<sub>5</sub> - C<sub>8</sub>), welche häufig von Pflanzen und Mikroorganismen emittiert werden, als auch infektionsspezifische Sesquiterpene (C<sub>15</sub>H<sub>24</sub>). In Zeitreihenversuchen konnte gezeigt werden, dass ein Großteil der relevanten VOCs bereits nach kurzer Zeit emittiert wird. So waren in Mais volatile Biomarker detektierbar, bevor Symptome am Kolben erkennbar waren (4 – 8 Tage nach der Inokulation). Ein Monitoring von VOC Profilen im Hinblick auf volatile Marker könnte eine schnelle und nicht-destruktive Detektion von <i>Fusarium</i> Infektionen (ggf. auch Risikoabschätzung zur Mykotoxinbelastung), z.B. im Feld oder Lager, ermöglichen. Hierfür stehen transportable Detektoren zur Verfügung. Das makrozyklische Lacton Zearalenon (ZEN) wird von mehreren <i>Fusarium</i> spp. produziert und besitzt eine östrogene Wirkung auf den menschlichen und tierischen Organismus. Schweine gelten diesbezüglich als besonders anfällig. ZEN wird in gemäßigten Klimazonen regelmäßig in Lebens- und Futtermitteln nachgewiesen. Bislang wurden zahlreiche Bioassays für die Detektion von ZEN beschrieben. Sie basieren meist auf den menschlichen Östrogenrezeptoren α und β und reagieren unspezifisch auf eine Vielzahl von östrogenen Substanzen (z.B. Genistein, 17β-Estradiol). Die vorliegende Arbeit beschreibt erstmalig ein Bioassay zur spezifischen Detektion von ZEN sowie dem kritischen Metabolit α-Zearalenol (α-ZOL). Das Assay basiert auf einer <i>zes2::gfp</i> Mutante des Mykoparasiten <i>Gliocladium roseum</i> und ermöglicht eine Detektion von ZEN in Feldproben (z.B. kontaminierter Mais). Schritte zur Probenvorbereitung und Extraktion, einschließlich Aufreinigung mit Immunoaffinitätssäulen, sowie die Kultur des Inditaktorstammes wurden optimiert. Das Assay eignet sich für die qualitative Detektion von ZEN in einem weiten Konzentrationsbereich sowie für eine quantitative ZEN Bestimmung in kontaminierten Mais Feldproben im Bereich zwischen 0,9 mg kg<sup>-1</sup> und 90 mg kg<sup>-1</sup>. Neben der Detektion in Feldproben, konnte das Bioassay erfolgreich für ein Screening von Pilzstämmen zur Identifikation von ZEN-Produzenten eingesetzt werden. Das hier beschriebene <i>G. roseum zes2::gfp</i> Bioassay kann mit einer einfachen Laborausstattung durchgeführt werden und eignet sich möglicherweise für die Anwendung in Entwicklungsländern.
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Biofiltro su suaktyvinta pušų žievių įkrova tyrimai ir taikymas orui valyti / Research on and application of the biofilter with activated pine bark charge for air purificationVaiškūnaitė, Rasa 02 June 2004 (has links)
To fill in this niche and to make the development of ecological biotechnologies more intense in Lithuania, a biofilter with the activated pine-bark charge has been designed at the Department of Environment Protection of Vilnius Gediminas Technical University; besides, complex research on biological air purification processes have been carried out with the help of this biofilter. Using biologically activated pine-bark charge in the developed filter, to carry out biological air purification research and to evaluate the efficiency of the theoretical and practical methods and its application. The fractionated charge of coniferous bark has been used in the special equipment with natural microflora cultivated for air purification from volatile organic compounds; and the potential of the employment of the developed equipment has been fully evaluated after theoretical and experimental researches and mathematical modelling. The experimental researches and their results prove that development and use of biofilters for air purification from volatile organic compounds at various production enterprises of Lithuania is promising. Its implementation is especially promoted by comparatively low capital and operation costs of air purification, high air purification efficiency and strict norms of pollutants emitted into the air set in the European Union.
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Biofiltro su suaktyvinta pušų žievių įkrova tyrimai ir taikymas orui valyti / Research on and applocation of the biofilter with activated pine bark charge for air purificationVaiškūnaitė, Rasa 07 June 2004 (has links)
To fill in this niche and to make the development of ecological biotechnologies more intense in Lithuania, a biofilter with the activated pine-bark charge has been designed at the Department of Environment Protection of Vilnius Gediminas Technical University; besides, complex research on biological air purification processes have been carried out with the help of this biofilter. Using biologically activated pine-bark charge in the developed filter, to carry out biological air purification research and to evaluate the efficiency of the theoretical and practical methods and its application. The fractionated charge of coniferous bark has been used in the special equipment with natural microflora cultivated for air purification from volatile organic compounds; and the potential of the employment of the developed equipment has been fully evaluated after theoretical and experimental researches and mathematical modelling. The experimental researches and their results prove that development and use of biofilters for air purification from volatile organic compounds at various production enterprises of Lithuania is promising. Its implementation is especially promoted by comparatively low capital and operation costs of air purification, high air purification efficiency and strict norms of pollutants emitted into the air set in the European Union.
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Oro taršos lakiaisiais organiniais junginiais tyrimas ir jos mažinimas naftos terminaluose / Research of pollution by volatile organic compounds in ambient air and its reduction in oil terminalsPaulauskienė, Tatjana 23 July 2008 (has links)
Disertacijoje nagrinėjama naftos ir jos produktų garavimo terminaluose problema. Pagrindinis disertacijos tikslas – įvertinti atmosferos taršą lakiaisiais organiniais junginiais (LOJ) naftos terminaluose, nustatyti meteorologinių elementų ir krovos indikatoriaus įtaką LOJ koncentracijos kitimui pažemės atmosferos sluoksnyje. Darbe sprendžiami keli pagrindiniai uždaviniai: ištirti LOJ pasiskirstymą pažemės atmosferos sluoksnyje už naftos terminalų teritorijos skirtingais metų sezonais atsižvelgiant į meteorologinius elementus ir krovos indikatorių; sudaryti skaitinį modelį, leidžiantį prognozuoti LOJ, i��siskyrimus iš esamų, ir rekonstruojamų terminalų, sklaidą uosto zonoje; remiantis tyrimų rezultatais ir jų analize, pasiūlyti technologinius sprendimus sumažinti ar išvengti LOJ emisijos į atmosferą naftos terminaluose. / This day environment pollution research and modern environment protection technology installation became a prior aspect not only in our country, but also in the whole world. The intensification and development of the industrial processes has a negative impact on human’s health and environment. As a result, it increases waste products accumulation. It also has a disbalance of natural processes and reckless waste of natural resources. All of the above can cause greenhouse effect formation. Because of intensive expansion of energy, in industrial and transportation sectors, there is significant increase in atmosphere pollution in last decade. The West part of Lithuania is one most polluted area by volatile organic compounds (VOCs), because there is a location of oil production and refinery industry, as well as intensive development of oil terminals. The problem is becoming more serious and relevant when these objects are located near urban areas.
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Research of pollution by volatile organic compounds in ambient air and its reduction in oil terminals / Oro taršos lakiaisiais organiniais junginiais tyrimas ir jos mažinimas naftos terminaluosePaulauskienė, Tatjana 23 July 2008 (has links)
This day environment pollution research and modern environment protection technology installation became a prior aspect not only in our country, but also in the whole world. The intensification and development of the industrial processes has a negative impact on human’s health and environment. As a result, it increases waste products accumulation. It also has a disbalance of natural processes and reckless waste of natural resources. All of the above can cause greenhouse effect formation. Because of intensive expansion of energy, in industrial and transportation sectors, there is significant increase in atmosphere pollution in last decade. The West part of Lithuania is one most polluted area by volatile organic compounds (VOCs), because there is a location of oil production and refinery industry, as well as intensive development of oil terminals. The problem is becoming more serious and relevant when these objects are located near urban areas. / Disertacijoje nagrinėjama naftos ir jos produktų garavimo terminaluose problema. Pagrindinis disertacijos tikslas – įvertinti atmosferos taršą lakiaisiais organiniais junginiais (LOJ) naftos terminaluose, nustatyti meteorologinių elementų ir krovos indikatoriaus įtaką LOJ koncentracijos kitimui pažemės atmosferos sluoksnyje. Darbe sprendžiami keli pagrindiniai uždaviniai: ištirti LOJ pasiskirstymą pažemės atmosferos sluoksnyje už naftos terminalų teritorijos skirtingais metų sezonais atsižvelgiant į meteorologinius elementus ir krovos indikatorių; sudaryti skaitinį modelį, leidžiantį prognozuoti LOJ, išsiskyrimus iš esamų, ir rekonstruojamų terminalų, sklaidą uosto zonoje; remiantis tyrimų rezultatais ir jų analize, pasiūlyti technologinius sprendimus sumažinti ar išvengti LOJ emisijos į atmosferą naftos terminaluose.
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Impact of Biogas Digesters on Health and Quality of Life Measures of Kenyan FarmwomenDohoo, Carolyn 05 August 2011 (has links)
Women living in rural Kenya rely on wood for cooking and are exposed to elevated amounts of wood smoke. The objective of this thesis was to assess the health and quality of life benefits of installing biogas digesters on rural Kenyan dairy farms. Thirty-one farms with biogas digesters and 31 farms without digesters (referent group) were assessed for wood utilization practices, basic respiratory and self-reported health, and exposure to volatile organic compounds (VOCs). Women with biogas digesters spent less time and money acquiring wood, and less time exposed to wood smoke (p<0.01). Multivariable linear regression showed associations between daily wood consumption and having a biogas digester, family size, and number of cows. Individual VOCs were lower in cookhouses on biogas farms (p<0.001) and women with biogas digesters reported fewer respiratory symptoms. Biogas digesters are one technology that can reduce reliance on wood fuel and reduce exposures to harmful wood smoke.
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