Wood Stove Use Research Articles

Environmental Tobacco Smoke, Woodstove Heating and Risk of Asthma Symptoms

The effect of common indoor combustion heating sources on childhood asthma is not well described. The objective was to determine if the use of woodstoves in the home or other factors such as environmental tobacco smoke exposure were associated with the frequency of asthma-related symptoms among children in a rural community. Having a person in the household who smoked was associated with a more than doubling in risk for wheezing and other asthma-related symptoms. The use of woodstoves or other types of heating in the homes of children was not associated with reported wheezing during the winter.

Enhancement of Thermal Efficiency of Traditional Indian Cooking Furnace (Chulha)

Energy is the prime mover of economic growth and it is a wheel of modern economy. Future economic growth crucially depends on the long-term availability of energy, and cost of sources, availability, accessibility, and environmental friendly. India is a developing country and it needs more energy to accelerate the rate of development. India has the sixth position in the total energy consumption in the world. The energy resource is constant but energy consumption increases day by day. So each country requires more energy efficient equipment for the development and to save energy consumption. There are three ways for efficient energy conversion (a) Discover new energy resource (b) To minimize the energy losses (c) waste heat recovery. Here every human needs the energy for cook food. In India 74% population of India lives in villages and uses the conventional resources e.g. wood, cow dung and agriculture waste and available of bio-mass. So, I select rural area where mostly use bio-mass fuel, like wood and agriculture waste. The chulha (wood stove) use as a cook furnace for bio-mass in rural area. The traditional chulha give low thermal efficiency. In view of conservation of wood fuel and reduction of smoke from the kitchens of rural. In view of conservation of wood fuel and reduction of smoke from the kitchens of rural India, the Ministry of Non-conventional Energy Sources(MNES), Government of India, launched a National Programme on Improved Chullhas(NPIC) during 1984- 85. The NPIC measure traditional Chullhas have thermal efficiency is 8 to 10 percent but in my modified model, thermal efficiency has improved by 15 to 17 percent through extra supply of air. The thermal efficiency of modified chulha over the conventional chulha is 7 % to 9% more. In my modified model do not create pollution into environment due to complete combustion of fuel.

PRELIMINARY INVESTIGATION OF EXCESS RESPIRATORY DISEASE HOSPITALISATIONS DOWNWIND OF AN URBAN PETROCHEMICAL COMPLEX

In the course of environmental impact hearings to review the siting of a new plastics plant, protesting citizens living adjacent to the existing Montreal (Canada) petroleum refinery/chemical complex where the plant was to be situated, invoked data showing that rates of hospitalisation for respiratory disease were already higher in their neighbourhood than elsewhere. The Montreal Public Health Department initiated a joint medical/environmental assessment to verify the citizens' complaints and to better characterise respiratory disease rates as related geographically to the industrial zone. Methods We extracted all hospitalisations by discharge diagnosis, by age, and street address for Montreal residents(population 2,000,000) during 1995–2000, identified neighbourhood-level rates of adult smoking and residential wood stove use, and classified neighbourhoods by their distance from and downwind position relative to the refinery/chemical complex. Results The two neighbourhoods (each of around 50,000 inhabitants) most subject to winds blowing off the complex are suburban in character, with adult residents whose educational status is slightly lower and mean family income somewhat higher than that of Montreal as a whole. Among children of 6 months-4years old, rates of hospitalisation for disease not associated with the respiratory system were slightly greater (RR = 1.33, 1.11) in the downwind neighbourhoods than for all of Montreal; for respiratory diseases overall, relative rates for the two neighbourhoods were 1.71 and 1.45. Excesses were also seen for acute hospitalisations related to pneumonia and to chronic pulmonary disease among neighbourhood residents aged over 60 years. While the proportion of adults smoking was somewhat higher in the neighbourhoods of concern than elsewhere, risk assessment assuming an RR of 2.0 for a parent who smokes, explained only 9% of the excess in children's respiratory hospitalisations. And while levels of SO2 were higher downwind of the refinery/chemical complex, the gradient was small and concentrations well below those associated with health effects in other situations. Conclusion The geographically-based excess of respiratory hospitalisations is not easily explained by community level exposure surrogates. We have initiated a migrant study and additional monitoring coupled with time-series analysis of hospitalisations to further assess the linkage of respiratory effects to emissions from local industry.

Infant respiratory symptoms associated with indoor heating sources.

This study examined the effects of indoor heating sources on infant respiratory symptoms during the heating season of the first year of life. Mothers delivering babies between 1993 and 1996 at 12 hospitals in Connecticut and Virginia were enrolled. Daily symptom and heating source use information about their infant was obtained every 2 weeks during the first year of life. Heating sources included fireplace, wood stove, kerosene heater, and gas space heater use. Four health outcomes were analyzed by reporting period: days of wheeze, episodes of wheeze, days of cough, and episodes of cough. A large percentage of infants had at least one episode of cough (88%) and wheeze (33%) during the heating season of the first year of life. Wood stove, fireplace, kerosene heater, and gas space heater use was intermittent across the study period. In adjusted Poisson regression models controlling for important confounders, gas space heater use was associated with episodes and days of wheeze. Wood stove use was associated with total days of cough, and kerosene heater use was associated with episodes of cough. Fireplace use was not associated with any of the respiratory symptoms. Use of some heating sources appears related to respiratory symptoms in infants.

The role of woodstoves in the etiology of nasal polyposis.

To determine the role of environmental pollutants in the etiology of nasal polyposis. Case-control study. A community-based hospital practice in the Gaspesian peninsula in rural northeastern Quebec. Fifty-five case patients with nasal polyposis and 55 age-matched control subjects without nasal polyposis who were seen at one physician's practice (J.K.) from March 1, 1998, to December 19, 1998. Exposure to woodstoves, indoor tobacco smoke, and pets and occupational exposures to noxious inhalant compounds. Forty-five (82%) of the cases, but only 14 (25%) of the controls, reported using woodstoves, yielding a crude odds ratio (OR) of 13.1. The corresponding risk associated with occupational exposure to noxious inhalant compounds was also high (OR, 6.1). When adjusted in various ways for the presence of other factors, these ORs remained high and statistically significant. For woodstove use, the point estimates of the ORs were consistently above 10, with the lower limits of 95% confidence intervals above 5. For occupational exposures to noxious inhalant compounds, the various adjusted OR estimates were above 6, with the lower limits above 1.5. There is a strong association between the use of woodstoves as a principal source of heating and the development of nasal polyposis. Occupational exposures to noxious inhalant compounds (other than tobacco smoke) also play an important role in its etiology.

Wood stove heating, asthma and allergies

In two German studies household wood or coal stove use was negatively associated with atopic sensitization and allergic rhinitis in childhood. Wood stove heating is strongly related to ‘traditional lifestyle’ and therefore subjected to confounding factors possibly yet not known. The study was conducted to study these factors and the independent impact of early exposure to wood stove heating on subsequent asthma and atopic disease. In a questionnaire survey among 10 667 Finnish university students aged 18–25 years, we investigated the association between wood stove heating at age 0–6 years and asthma and allergies up to young adulthood. Adjustment was made for factors related to the heating system and atopic disorders by using multivariate regression. Unadjusted lifetime prevalence rates for physician-diagnosed asthma, allergic rhinoconjunctivitis, atopic dermatitis and self-reported wheezing were lower among subjects with wood stove heating compared to other heating systems. There was a significant negative association between childhood wood stove heating and allergic rhinitis or conjunctivitis in the univariate model (OR 0·61, 95% CI 0·61–0·91), but not for the other diseases. The significant association disappeared in the multivariate analysis after adjusting for various family, indoor and outdoor (adjusted OR 0·96, 95% CI 0·77–1·20) factors. The association between wood stove heating and allergic rhinoconjunctivitis was mainly confounded by childhood residential environment, especially the farm environment. Farm environment was found to be the main confounding factor related to association between wood stove heating and asthma, and atopic diseases.

A Current Assessment of Rurally Linked Exposures as Potential Risk Factors for Sarcoidosis

PURPOSE: To identify and quantify the risk of developing sarcoidosis associated with specific rural exposures previously recognized as potential risk factors for this disease. METHODS: A matched case-control design was carried out with a 2-to-1 ratio of controls to cases. Case exposure histories were determine from a detailed questionnaire collecting self-reported information covering the period from birth through disease development and comparing that to exposure histories for the corresponding period in age-, race-, and gender-matched controls identified using Random Digit Dial survey methodology. Conditional logistic regression was used to analyze the matched data while controlling for several baseline variables. RESULTS: A number of exposures were found to be univariately associated with the development of sarcoidosis including: the use of wood stoves, the use of fireplaces, the use of nonpublic water supplies, and living or working on a farm. A dose-response gradient was detected from exposure to wood stoves and fireplaces continued to be significantly associated with sarcoidosis in multivariable models. CONCLUSIONS: The results of this study provide further support for the hypothesis that behaviors associated with rural living play some role in the development of sarcoidosis. This study further suggests that exposures involving the handling or burning of wood such as using wood stoves or fireplaces for home heating may, in part, explain this rural association.

Indoor Risk Factors for Asthma and Wheezing among Seattle School Children

Indoor risk factors for physician-diagnosed asthma and wheezing in the past 12 months without previous asthma diagnosis were assessed in a survey of parents of 5-9-year-old Seattle primary school students. Among the 925 respondents, 106 (11%) reported a physician diagnosis of asthma, 66 (7%) had wheezing without diagnosis, and 753 (82%) were asymptomatic. After adjusting for age, sex, gender, ethnicity, medical history, socioeconomic status (SES) and parental asthma status, an increased risk of physician diagnosis of asthma was associated with household water damage, the presence of one or more household tobacco smokers, and at least occasional environmental tobacco smoke (ETS) exposure. Similarly, an increased risk of wheezing in the past 12 months among children without diagnosed asthma was associated with household water damage, presence of one or more household tobacco smokers, and occasional or more frequent ETS exposure. No increased risk of either condition was associated with gas, wood, or kerosene stove use, household mold, basement water, or wall/window dampness. Similarities in the indoor risk factors patterns between diagnosed asthma and wheezing without diagnosis suggested a similar etiology of these two conditions. The slightly higher association between ETS and asthma may indicate that parents of diagnosed asthmatics were more conscious of ETS, and were more likely to prohibit household smoking by resident smokers. Future research is needed to quantify which aspects of household water damage are related to respiratory illness.

Indoor air pollution and asthma. Results from a panel study.

Although there is abundant clinical evidence of asthmatic responses to indoor aeroallergens, the symptomatic impacts of other common indoor air pollutants from gas stoves, fireplaces, and environmental tobacco smoke have been less well characterized. These combustion sources produce a complex mixture of pollutants, many of which are respiratory irritants. We report here results of an analysis of associations between indoor pollution and several outcomes of respiratory morbidity in a population of adult asthmatics residing in the Denver, Colorado, metropolitan area. A panel of 164 asthmatics recorded in a daily diary the occurrence of several respiratory symptoms, nocturnal asthma, medication use, and restrictions in activity, as well as the use of gas stoves, wood stoves, or fireplaces, and exposure to environmental tobacco smoke. Multiple logistic regression analysis suggests that the indoor sources of combustion have a statistically significant association with exacerbations of asthma. For example, after correcting for repeated measures and autocorrelation, the reported use of a gas stove was associated with moderate or worse shortness of breath (OR, 1.60; 95% CI, 1.11-2.32), moderate or worse cough (OR, 1.71; 95% CI, 0.97-3.01), nocturnal asthma (OR, 1.01; 95% CI, 0.91-1.13), and restrictions in activity (OR, 1.47; 95% CI, 1.0-2.16). Among this panel of relatively moderate to severe asthmatics, the respiratory irritants produced by several domestic combustion sources were associated with increased morbidity.

Immunologic biomarkers associated with an acute exposure to exothermic byproducts of a ureaformaldehyde spill.

A community was exposed for several days to formaldehyde (HCHO), hexamethylenetetramine, trimethylamine, and paraformaldehyde emitted from an overheated tanker car containing ureaformaldehyde resin. Residents experienced acute HCHO symptoms at the time of the accident. Many developed chronic, multiple organ health complaints. Three years following the accident, exposed subjects were compared to residents of a nearby unexposed community for the following immunological parameters: white blood cell count, total lymphocyte count, percent and total lymphocyte subsets (CD5, CD4, CD8, CD19, CD25, and CD26 cells), prevalence of autoantibodies, and antibodies to HCHO-human serum albumin (HCHO-HSA) conjugate. The data were adjusted for gender, age, history of smoking, mobile home residency, and use of wood stoves. There was a statistically significant difference for the following: elevated percent and absolute numbers of CD26 cells (p less than 0.0001); autoantibodies (p less than 0.004), and greater titers of isotypes IgG (p less than 0.0005) and IgM (p less than 0.005) to HCHO-HSA. It is concluded that the exposed subjects had an activated immune system in addition to the elevated autoantibodies. Also, isotypes to HCHO-HSA resulted from the exposure and no other sources, such as smoking, mobile home residency, and use of wood stoves.

The Effect of Wood and Coal Stoves on Household Use of Electricity

Since the energy crises of the 1970s, price increases have induced many forms of electric energy saving by households. Among these is the use of wood and coal stoves, which are an important alternative space heating system in regions where these fuels are readily available. A stove may substitute to various degrees for the major heating system built into the dwelling, depending on the characteristics of the dwelling and household usage patterns. The study of detailed household data makes it both possible and desirable to give wood and coal stoves adequate consideration. The reduction in electric energy consumption of a household due to the use of a stove is estimated in this study to exceed the average kilowatt-hour (kWh) use of a wide range of electric appliances that are more usually treated in electricity demand studies.' The decision to install a stove and the decision determining the level of operation of a stove are related to, among other things, the price of electricity. When the price of electricity increases, other things being equal, stove ownership and use increase and electric heating consumption is suppressed. The aim of this paper is to quantify these effects, which are part of the long-term adjustment to an electric price increase. The results obtained here ultimately bear upon utility rate and system planning decisions, and also upon questions of energy policy, which require information concerning household fuel substitution and responsiveness to price.2 The body of the paper has three sections. The first explains the analysis of kWh demand, conditional upon equipment stocks. The second explains the stove ownership models. The third briefly explains the construction of a residential simulation model and reports the results of an experiment which quantifies the reduction in kWh consumption due to the use of stoves.

Contribution of wood stoves and fire places to mutagenic activity of airborne particulate matter inside homes

Wood combustion produces compounds that are mutagenic in the Salmonella/microsome assay. As combustion products can be emitted in the home and the use of wood as a residential energy source is growing, an impact on human health might be of concern. In this study experiments were carried out to determine the contribution of wood combustion in stoves and fire places to indoor mutagenic activity under normal living conditions. Airborne particles from living rooms which were heated by stoves, or by fire places, and from outdoors were collected simultaneously. In each room two samples were collected during two consecutive weeks: one week the room was heated by central heating, the other week by wood combustion. Sampling took place in a total of 24 homes. Methanol extracts of the samples were tested in the Salmonella/mammalian microsome assay. Results show that mutagenic activity of outdoor air exceeds indoor mutagenicity. At the same time a correlation is found between in- and out-door mutagenicity, both with and without S9. However, a large difference is found between the ratio −S9/+ S9 of in- and out-door mutagenic activity. Systematic differences in the ratio −S9/+ S9 between control and experimental conditions are not observed. The use of wood stoves caused an increase of indoor mutagenicity in 8 out of 12 homes. It could be concluded that the use of an open fire consistently leads to an increase of mutagenic activity. This increase was caused by wood combustion products.

Woodstoves, formaldehyde, and respiratory disease.

Telephone interviews were completed in Western Massachusetts in April 1983 for 399 households (91.5 per cent) in a random sample of households with elementary school children. Woodstoves were used in 64.7 per cent of the homes, but such use was not associated with acute respiratory illness. However, formaldehyde exposure was significantly related, with a risk ratio of 2.4 (95 per cent confidence interval 1.7-3.4). New construction/remodeling and new upholstered furniture had additive effects. Neither woodstove use nor formaldehyde exposure were significantly associated with asthma, chronic bronchitis, or allergies.

The effects of woodburning on the indoor residential air quality

Data from suburban residences in the Boston metropolitan area reveal a potential adverse impact on indoor air quality from woodburning in woodstoves and fireplaces. Ambient pollutant concentrations at each residence were compared to corresponding pollutant levels indoors at three locations (kitchen, bedroom, and activity room). Individual gaseous pollutant samples were averaged on an hourly basis while 24-h integrated samples of particulate matter were obtained. Ten gaseous pollutants were sampled along with total suspended particulates (TSP). Chemical analyses further determined ten components of TSP including trace metals, benzo- a-pyrene(B) aP, respirable suspended particulates (RSP), and water soluble sulfates and nitrates. Monitoring lasted two weeks at each residence and was conducted under occupied, real-life, conditions. Observed, elevated indoor concentrations of TSP, RSP, and B aP are attributed to woodburning. Data indicate that average indoor TSP concentrations during woodburning periods were about three times corresponding levels during nonwoodburning periods. The primary 24-h national ambient air quality standard (NAAQS) for TSP was exceeded once indoors during fireplace use, and the secondary, 24-h TSP NAAQS, was also exceeded indoors by RSP concentrations. Indoor B aP concentrations during woodstove use averaged five times more than during nonwoodburning periods. At this stage, results are only indicative, but the potential impact from elevated indoor concentrations of TSP, RSP, and B aP, attributed to woodburning, may have long-term health implications.

Household Demand for Firewood in Rhode Island

Data from a sample of Rhode Island households indicate that firewood use along with wood stove use is increasing in response to increases in conventional heating fuel costs. More than half the sample of households reported the intention to reduce their heating fuel costs as their primary reason for burning wood. For nearly 20 percent of the households, the 1977–78 study season was the first heating season that these households had burned firewood. Among wood stove users, 50 percent began using a wood stove for the first season, the 1977–78 study season. Regression results indicate that the variables price, income and primary reason firewood is burned are important in the household's decision on the quantity of firewood burned.

Program to demonstrate use of cotton in paper making announced

Due to temperature inversions and widespread residential woodstove use, Libby, Montana historically experienced elevated levels of ambient woodsmoke PM2.5 throughout the winter months. In an effort to reduce wintertime PM2.5, a large community–wide woodstove changeout was conducted between 2005 and 2007, removing nearly 1 200 old polluting stoves from service. To determine the impact of this intervention on indoor air quality, PM2.5 sampling was conducted in the gymnasiums of an elementary and middle school before, during, and after the woodstove changeout over a four–year period. Throughout the program, results showed that indoor PM2.5 concentrations at the elementary school were moderately high regardless of year or season (mean±sd, 31.9±14.1 µg/m3), ranging from 11.0 µg/m3 to 79.3 µg/m3. At the middle school, the mean was 12.2±11.2 µg/m3, with no differences by season. Although there was an overall improvement in ambient air quality (and reduction of woodsmoke–PM2.5) when comparing pre– and post– changeout PM2.5 concentrations, results suggest that the community–wide woodstove changeout did not have a significant impact on indoor air quality within the gymnasiums over this same time period. These findings are supported by the results of selected chemical markers of woodsmoke measured from indoor PM (including levoglucosan) at both schools, which also demonstrated no significant reductions throughout the four–year sampling program.