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American Journal of Epidemiology Advance Access originally published online on December 22, 2006
American Journal of Epidemiology 2007 165(6):634-642; doi:10.1093/aje/kwk117
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American Journal of Epidemiology Copyright © 2006 by the Johns Hopkins Bloomberg School of Public Health All rights reserved; printed in U.S.A.

ORIGINAL CONTRIBUTIONS

Risk of Lung Cancer from Residential Heating and Cooking Fuels in Montreal, Canada

Agnihotram V. Ramanakumar1, Marie-Elise Parent2 and Jack Siemiatycki1,3

1 CHUM Research Centre, University of Montreal, Montreal, Quebec, Canada
2 INRS – Armand-Frappier Institute, University of Quebec, Laval, Quebec, Canada
3 Department of Social and Preventive Medicine, University of Montreal, Montreal, Quebec, Canada

Correspondence to Prof. Jack Siemiatycki, CRCHUM, 3875 St-Urbain #312, Montreal, Quebec H2W 1V1, Canada (e-mail: j.siemiatycki{at}umontreal.ca).

Received for publication March 2, 2006. Accepted for publication July 28, 2006.


   ABSTRACT
TOP
 ABSTRACT
INTRODUCTION
 MATERIALS AND METHODS
 RESULTS
 DISCUSSION
 References
 
Among the major sources of indoor air pollution are combustion by-products from heating and cooking. Concern is increasing that use of polluting heating and cooking sources can increase cancer risk. In Canada, most cooking and heating currently relies on electricity or natural gas, but, in the past, and still in some areas, coal and wood stoves were used for heating and gas and wood for cooking. In the course of a case-control study of lung cancer carried out in Montreal in 1996–2001, the authors collected information on subjects' lifetime exposure to such sources of domestic pollution by means of a personal interview with the subject or a next-of-kin proxy. Questionnaires were completed for 739 male cases, 925 male controls, 466 female cases, and 616 female controls. Odds ratios were computed in relation to a few indices of exposure to traditional heating and cooking sources, adjusting for a number of covariates, including smoking. Among men, there was no indication of excess risks. Among women, the odds ratio for those exposed to both traditional heating and cooking sources was 2.5 (95% confidence interval: 1.5, 3.6; n = 253). The findings for women suggest the need for research dedicated to exploring this association, with particular emphasis on improved exposure assessment.

air pollution, indoor; Canada; case-control studies; cookery; fossil fuels; heating; lung neoplasms


   INTRODUCTION
TOP
 ABSTRACT
 INTRODUCTION
MATERIALS AND METHODS
 RESULTS
 DISCUSSION
 References
 
Indoor air pollution is a public health problem in both developed and developing countries (1). Among the major sources of indoor air pollution are combustion by-products from heating and cooking. Different heating and cooking technologies and fuels imply different types and levels of indoor air pollution. Among the "dirtiest" types of heating and cooking systems are wood and coal stoves or fireplaces located in the living areas. Wood and coal are currently used in many areas of the world for both heating and cooking and, up to the mid-20th century, were the main fuels used in what are now considered developed countries (1). While these fuels are no longer dominant in developed countries, there has been some increase in the past decade in the use of wood for heating and cooking, at least as a supplementary system, and natural gas remains a fairly prevalent fuel for cooking (2). Combustion of these fuels emits a variety of pollutants (1), some of which are recognized or suspected carcinogens (3–5).

In many developing countries, cooking facilities in homes often consist of open-hearth fireplaces that are left smoking for long periods and produce considerable indoor pollution (1). It has been shown in Asia that women living in homes with such cooking facilities experience excess lung cancer risks (6, 7).

There has been growing concern in developed countries that the use of polluting heating and cooking sources can pose a threat to health and, in particular, might increase lung cancer risk. Homes in North America are increasingly built to be airtight and thus to reduce ventilation rates. In addition, North Americans spend a very high proportion of their time indoors (8). Little is known of the risks of cancer that may be induced by combustion of traditional fuels in developed countries.

Montreal, Canada, has a cold climate for about 6 months per year, and home heating is generally needed during this period. Since the 1950s, traditional heating and cooking sources have largely given way to electricity, now used in about half of the households for heating and about 90 percent for cooking; oil and natural gas are the other main fuels used. However, many people now in the age range at risk for lung cancer experienced traditional heating and cooking sources when they were much younger, especially those who grew up in rural areas. Recently, there has been a resurgence in the use of some traditional fuels—gas for cooking and wood for heating (9). It is important to determine whether such exposures had any influence on cancer risks among people who experienced them.

We had a unique opportunity to address this issue by using a case-control study conducted in Montreal, with subjects interviewed from 1996 to 2001. The primary focus of the study was the possible role of occupational exposures in cancer etiology. However, data were collected on subjects' exposure to traditional heating and cooking sources as well as on a host of sociodemographic, medical, environmental, occupational, and lifestyle characteristics. The present analysis describes possible associations between heating and cooking fuel sources and lung cancer.


   MATERIALS AND METHODS
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
RESULTS
 DISCUSSION
 References
 
The study was conducted in Montreal and its surrounding suburbs, an area containing a population of 3.1 million in 1996. It included males and females aged 35–75 years who were Canadian citizens residing in the study area.

Case ascertainment
Cases were ascertained in the 18 largest hospitals located in the metropolitan area. These hospitals accounted for over 98 percent of all lung cancers diagnosed in the area (Michel Beaupré, Quebec Tumor Registry, personal communication, 1994). Cases were ascertained through hospital tumor registries or through active monitoring of pathology department records. Only histologically confirmed cases diagnosed between January 1996 and December 1997 were included. A total of 1,434 eligible cases were ascertained. Attempts were made to interview these cases personally or, for subjects who died before the interview attempt or who were very ill, to interview their next of kin. Interviews were conducted for 1,205 cases, representing a response rate of 84 percent. On average, the interval between diagnosis of cancer and interview was about 1 year. More than one third of case interviews were conducted with proxy respondents. For cases, those for whom proxies responded tended to be older, to have more advanced disease at diagnosis, and to be heavier smokers. However, they were similar to self-respondents regarding ethnicity, socioeconomic status, and schooling.

Control selection
Controls were randomly sampled from the population-based electoral lists, stratified by sex and age to the distribution of cases. In Canada, the electoral list is compiled by an active door-to-door enumeration, and it is thought to be a virtually complete listing of citizens of voting age. Of 2,182 eligible controls selected, 1,541 were interviewed (response rate of 71 percent). There were a small number of proxy interviews for controls (7.8 percent), which occurred when the sampled person was unavailable because of illness, travel, or communication difficulties.

Data collected
After informed consent was obtained, interviews were conducted for all subjects by trained and bilingual (English and French) interviewers using a structured questionnaire. Detailed information was collected on sociodemographic characteristics, residential history, housing characteristics, medical history, history of smoking, frequency of intake of selected dietary items, detailed occupational history, and domestic exposure to traditional heating or cooking sources. On the basis of occupational history, a team of industrial hygienists inferred exposure to nearly 300 occupational chemicals (10).

The following questions were asked regarding cooking fuels and heating sources: "Have you ever lived full-time in a house or apartment where the cooking was done on a gas or wood stove?" (We refer to these as traditional cooking sources.) "Have you ever lived full-time in a house or apartment that was mainly heated by a stove or fireplace located in the living quarters?" (We refer to these as traditional heating sources.) These questions were stratified by two time windows: up to and including 20 years of age and after 20 years of age; for each window, duration of exposure was elicited in two categories (1–9 years and ≥10 years).

The histology of lung cancer was coded per World Health Organization/International Agency for Research on Cancer technical report 31 (11). The smoking history that we collected from study subjects was quite standard in relation to most modern case-control studies, with information requested on age at which smoking began, age at which smoking ended, and average amount smoked.

Statistical analysis
In addition to simple descriptive statistics to characterize the study populations, we assessed the associations between traditional heating and cooking sources and lung cancer. Unconditional multivariate logistic regression models were used to estimate odds ratios and 95 percent confidence intervals (12). The following variables were included as potential confounders: age; sex; years of school attendance; mean family income of the census tract of residence; occupational exposure to asbestos, silica, chromium compounds, and environmental tobacco smoke; detailed smoking history; and type of interview (self, surrogate). A smoker was defined as someone who smoked at least 100 cigarettes in his or her lifetime; a former smoker was defined as someone who stopped smoking at least 2 years before the interview. Smoking history was represented by three variables according to the recommendations of Leffondré et al. (13): a binary variable indicating whether the person was ever a smoker, a continuous cigarette-years variable, and time since quitting in five categories (0–2 years, 3–5 years, 6–10 years, 11–15 years, ≥16 years). All variables that could be represented as continuous were modeled as such. Furthermore, we examined effect modification of the associations of interest by several covariates, namely, attained age at diagnosis of lung cancer, smoking status, and self or proxy respondent status. Odds ratios were also computed by histologic type of cancer. Analyses were carried out by using Stata statistical software (14).


   RESULTS
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
 RESULTS
DISCUSSION
 References
 
The sociodemographic characteristics of study subjects are presented in table 1. About 20 percent of cases were less than age 55 years when they were diagnosed with lung cancer. Fewer than 3 percent of male cases and fewer than 8 percent of female cases were nonsmokers. Cases were more likely to be smokers, and the cases who smoked had higher cigarette-years of exposure than the controls who smoked. Compared with controls, cases had lower incomes and were more likely to be French Canadian. Fewer cases than controls were born outside North America. There were more proxy responders among cases than among controls. All of these covariates were taken into account in the analyses.


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  		TABLE 1. Selected characteristics of subjects from a case-control study of lung cancer, Montreal, Canada, 1996–2001*,{dagger}

 
Table 2 summarizes the lifetime prevalence of exposure to traditional heating and cooking fuels among cases and controls. The lifetime exposure prevalence to traditional heating sources was about 50 percent. The lifetime exposure to traditional cooking sources was approximately 75 percent. Most of the exposed subjects had been exposed at less than 20 years of age, and most had been exposed to both traditional cooking and traditional heating sources. While we did not ascertain the precise number of years of exposure, the vast majority of exposed subjects were exposed for more than 10 years.


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  		TABLE 2. Selected indices of exposure to traditional heating and cooking sources (%) in a case-control study of lung cancer, Montreal, Canada, 1996–2001*

 
Table 3 describes the odds ratios for the association between traditional fuels and lung cancer. Among men, there was no evidence of associations with either traditional heating or traditional cooking sources. Among women, there was quite strong evidence of associations for both heating sources and cooking sources. Exposure to traditional heating and cooking sources was strongly correlated. When both variables—heating and cooking—were included in statistical models, the odds ratios were hardly affected, indicating that both might have made independent contributions to risk. Nearly all women exposed after the age of 20 years had also been exposed in childhood, making it impossible to disentangle the effects of age at exposure.


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  		TABLE 3. Odds ratios* for the association between lung cancer and selected indices of exposure to traditional heating and cooking sources in a case-control study in Montreal, Canada, 1996–2001

 
Table 4 shows some of the associations between lung cancer and fuel sources, stratified on attained age, smoking status, and type of respondent. In this set of analyses, we combined exposure in childhood and adulthood into a single binary lifetime exposure variable. Among males, there was no evidence of effect modification by any of the stratification variables. Among females, there was some indication that the associations were stronger for older subjects, heavier smokers, and self-respondents. When these differences were tested with interaction terms in the models, those for age and smoking were statistically significant (p < 0.05).


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  		TABLE 4. Odds ratios* for the association between exposure to traditional heating and cooking fuel sources and risk of lung cancer, stratified by selected characteristics, from a case-control study in Montreal, Canada, 1996–2001

 
The associations between exposure to traditional fuels and histologic types of lung cancer are shown in table 5. The associations were strongest for small cell and squamous cell tumors and weakest for adenocarcinomas.


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  		TABLE 5. Odds ratios* for the association between exposure to traditional heating and cooking fuel sources and selected histologic subtypes of lung cancer, from a case-control study in Montreal, Canada, 1996–2001

 

   DISCUSSION
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
 RESULTS
 DISCUSSION
References
 
In Canada and in many developed countries, until the middle of the 20th century, it was common to heat homes with coal or wood, and sometimes the stoves or furnaces were in or near the living space. The same appliance might be used for cooking, particularly in rural areas. In the past 50 years, there has been increasing use of electricity, oil, and gas. Recently, there has been a resurgence in the use of wood stoves, with about 10 percent of Quebec residents now reporting that they use wood for heating (9). Electricity is inherently cleaner than other sources. Oil or gas heating usually involves a furnace located away from living space in the house. However, gas used for cooking means combustion in the living space. Our questionnaire focused on those types of heating and cooking sources that were most likely to cause pollution in the living space.

Given the nature of the combustion sources, it may be inferred that traditional heating and cooking fuels might produce a variety of indoor pollutants, including respirable particles, heavy metals, polycyclic aromatic hydrocarbons, carbon monoxide, carbon dioxide, nitrogen dioxide, sulfur dioxide, and formaldehyde. Exposure to indoor air contaminants from heating and cooking activities depends on the unique combination of a host of factors such as type of fuel, source of fuel, physical characteristics and layout of the dwelling, presence of other air contaminants, location of the heating or cooking appliance, use patterns of the appliances, ventilation conditions, season, and time of day (5, 15, 16).

Unfortunately, little representative and generalizable information is available on levels of indoor pollution induced by different forms of cooking and heating. There have been only a few attempts to measure such pollutants. In a German survey (17), concentrations of carbon monoxide, heavy metals, and polycyclic aromatic hydrocarbons were higher in homes with open fireplaces in the living room than in homes with central heating, while concentrations of carbon dioxide were similar in both heating systems. It was also noted in that survey that indoor pollution levels in homes with central heating systems can be high when exhaust systems malfunction (17). In a US survey, it was reported that levels of nitrogen dioxide, sulfur dioxide, and carbon dioxide were elevated in homes with oil space heaters and in homes with gas cookers (18). Significant levels of benzene pollution have been reported in relation to the use of kerosene as a cooking fuel (19). In a survey in Quebec City, there was no indication of high levels of formaldehyde, nitrogen dioxide, respirable particles, or carbon monoxide in homes with wood-burning stoves, although residents who mentioned being exposed to fumes from such appliances reported more respiratory illnesses and symptoms than those who did not report such exposure (20). In another survey, comparing pollutant levels in homes that used different types of gas, it was found that many pollutants were detected, but levels were somewhat lower with natural gas than with propane or with liquefied petroleum gas (21).

In developing countries, most households depend on combustion of biofuels such as wood, crop residues, and animal dung for cooking or heating (22). Since there is usually no chimney and poor ventilation, these combustion sources, combined with the foods being cooked and tobacco smoke, often make for quite smoky indoor environments (22). There has been growing evidence from developing countries that domestic exposure to combustion of fuel may be harmful to health. There have been reports that emissions from traditional fuels increase risks of tuberculosis (23, 24), asthma attacks (23, 25–27), other acute respiratory diseases (23, 25), chronic obstructive pulmonary diseases (23, 27, 28), pharyngeal cancer (29, 30), laryngeal cancer (29, 30), and lung cancer (7, 31–39). Regarding lung cancer, the strongest evidence comes from studies among women, mostly nonsmokers, from China and India (35, 36, 38). The studies that have been conducted, however, are of variable size and quality, and they comprise a variety of different exposure circumstances.

Few studies have examined lung cancer risks due to domestic fuel use in developed countries. Among White women in Los Angeles, California, there were elevated risks of lung cancer in relation to self-reported history of exposure to coal/wood stoves and fireplaces during childhood or teenage years (40). A multicenter study in eastern Europe and the United Kingdom showed no risk increase related to use of solid fuels as heating sources; however, there was a small excess risk ranging from 20 percent to 40 percent for those who used such fuels for cooking (41).

Among the strengths of the present study are population-based subject accrual, histologic confirmation of lung cancers, availability of smoking history and other characteristics, inclusion of both males and females, large sample sizes, and a climate in which heating is necessary for a good part of the year. Furthermore, our study was carried out in a population unique in North America for its rather narrow ethnic diversity. Two thirds of the study population was of French origin. This factor considerably diminishes the risk of confounding by genetic and environmental (e.g., dietary) factors related to ethnicity.

Our team conducted a case-control study in the same geographic area in the early 1980s using a design and questionnaire similar to that in the present study. The previous study included only men and the same questions as those used in the present study on exposure to traditional heating and cooking sources. We found that the percentage of men who had never been exposed to such heating and cooking sources was very low: only 12 percent among population controls. This finding led to very low power to detect any excess risks, and we demurred from formally publishing the findings. Still, it is noteworthy that the analysis of risk showed odds ranging from 1.0 to 1.4 in the various exposure subgroups, albeit with wide confidence intervals. Together, the results concerning men from the two studies are compatible with the null hypothesis of no effect due to traditional fuels, although the results cannot rule out the hypothesis of a small excess in risk.

Among women, by contrast, risks were approximately doubled for those who reported having lived in homes heated by wood or coal stoves in the living areas or who reported having lived in homes where cooking was done on wood or gas stoves. There was a great deal of overlap between those exposed in adulthood and in childhood, and also great overlap between those exposed to traditional heating and traditional cooking. It was thus difficult to attribute the apparent excess risks to one type of exposure or one age window of exposure, even though the data hinted at slightly higher risks for those exposed to traditional heating.

Some sources of bias are possible. Information bias between cases and controls seems unlikely. There is no obvious reason why such bias would appear for females but not males. For other variables in our questionnaire, there was no systematic pattern of higher reporting of exposures among cases versus controls. The fact that there was a 1-year interval, on average, for cases between date of diagnosis and date of interview, while there was no equivalent interval for controls, meant that cases were in effect recalling events that happened slightly further distant in time. However, the events being recalled were many decades earlier for both groups, and it is hardly credible that the 1-year difference in time frame would bias the comparison. Furthermore, if there were such a bias, it would operate in the direction of decreasing the reporting of exposure among cases, thus opposite to the observed associations. It is noteworthy that the apparent excess risks were higher among self-respondents than proxy respondents, increasing the credibility of this result.

When dealing with lung cancer as an outcome, the assessment and control of smoking history is an obvious concern. Modeling of smoking history was based on an analysis conducted in an earlier study, in which the optimal parameterization was a set of three variables, as described in our methods section (13). Few, if any, previous studies have been as thorough in controlling for smoking. Nevertheless, it cannot be taken for granted that there was no residual confounding by smoking, and indeed there were some indirect indications of possible residual confounding. First, the odds ratios for cooking and heating sources were somewhat higher for medium and heavy smokers than for nonsmokers and light smokers, although elevated odds ratios were also seen in the latter subgroup. A second indirect indication of residual confounding by smoking was the pattern of results by histologic types: the strongest associations for small and squamous cell cancers and the weakest for adenocarcinomas. Although the differences were not large, they nevertheless mimic the pattern of associations between smoking and types of lung cancer. A similar pattern was discernable in the eastern European study (41). Even though residual confounding by smoking is one plausible explanation for such a pattern, another is the possibility that these indoor pollutants produce the same pattern of risk as tobacco smoke.

There are two arguments against the notion that residual confounding by smoking entirely explains the excess risk observed among women. First, it is unlikely that such bias would have acted among women but not among men (who smoked much more). Second, for residual confounding to have induced a spurious twofold relative risk, the correlation between smoking and exposure to traditional fuels, conditional on the correlation adjusted by using our three-variable approach, would have to be quite strong. Even if there is a correlation between smoking behavior and exposure to traditional fuels, the partial correlations, after accounting for smoking as we did, are unlikely to be so high as to induce spurious twofold risks.

Confounding by other factors is a possibility. Among population controls, subjects who had been exposed to traditional heating and cooking sources tended to differ from subjects who had never been exposed in the following respects: they were older, they smoked more, and they had fewer years of schooling. There were small differences in ethnicity and income. Because we adjusted for all of these covariates, it is unlikely that they confounded the results. Environmental tobacco smoke is a possible confounder that we cannot rule out, although it is difficult to see how it could induce an artifactual twofold relative risk when the best estimate of the main effect of environmental tobacco smoke is about 1.3 (42). It is not obvious to imagine other risk factors for lung cancer that are correlated with traditional heating and cooking sources, independently of the various socioeconomic factors we adjusted for, for only women.

A major limitation was the crude nature of the exposure variables we collected. A tremendous variety of exposure circumstances can be subsumed by such phrases as "a house or apartment where the cooking was done on a gas or wood stove" or "a house or apartment that was mainly heated by a stove or fireplace located in the living quarters." It is not clear that respondents had a common understanding of those phrases, and it is clear that the affirmative responses elicited by those phrases do not necessarily imply similar profiles and concentrations of domestic pollution. The vagueness of these exposure measures certainly lends itself to misclassification error, which would have the effect of attenuating any relative risk estimates. Still, we believe that, on average, those who responded in the affirmative did experience higher levels of domestic fuel-derived pollution than those who responded in the negative.

Including this study, most of the evidence that shows an association comes from studies conducted among women, although some studies also found excess risks for men (34, 39). Higher risks for women than men due to domestic pollution are compatible with the fact that women spend a greater portion of the day indoors on average (37, 38) and a greater portion of time than men do in proximity to kitchen cooking facilities, particularly in the past.

Given the paucity of evidence from developed countries and the equivocal nature of that evidence, it is certainly premature to draw conclusions. However, our study supports the hypothesis that there might be an increased risk of lung cancer for women exposed to traditional heating or cooking fuels, and it highlights the need for research with more refined assessments of the exposures of interest.


   ACKNOWLEDGMENTS
 
Collection of original data was supported by grants from the Institut de recherche en sante et securite du travail du Quebec, the National Health Research and Development Program, the National Cancer Institute of Canada, and the Medical Research Council of Canada (Principal Investigator: Prof. Jack Siemiatycki).

Prof. Siemiatycki holds a Canada Research Chair in Environmental Epidemiology and Population Health at the Universite de Montreal, Montreal, Canada. Dr. Agnihotram V. Ramanakumar is supported by a postdoctoral fellowship grant from the National Cancer Institute of Canada, under the PREECAN (Programme of Research in Environmental Etiology of Cancer). Dr. Marie-Elise Parent is Associate Professor at the Institut Armand-Frappier of the Institut national de la recherche scientifique (INRS) of the Universite du Quebec, Laval, Canada.

Conflict of interest: none declared.


   References
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
 RESULTS
 DISCUSSION
 References
 

  1. Smith KR, Mehta S, Fuez M. (2003) Indoor air pollution from household use of solid fuels. In Ezzati M, Rodgers AD, Lopez AD (Eds.). Comparative quantification of health risks: global and regional burden of disease due to selected major risk factors(World Health Organization, Geneva, Switzerland) Vol 2:.
  2. Zebre JI. (2004) Non-wood products/Energy from wood. (USDA Forest Products Laboratory, Madison, WI) (http://www.fpl.fs.fed.us/documnts/pdf2004/fpl_2004_zerbe001.pdf). (Accessed July 2006).
  3. Basu R and Samet JM. (1999) A review of epidemiological evidence on health effects of nitrogen dioxide exposure from gas stoves. J Environ Med 1:173–7.[CrossRef]
  4. Zhang J and Smith KR. (1996) Hydrocarbon emissions and health risks from cook stoves in developing countries. J Expo Anal Environ Epidemiol 6:147–61.[Web of Science][Medline]
  5. Zhang J and Smith KR. (1999) Emissions of carbonyl compounds from various cook stoves in China. Environ Sci Technol 33:2311–20.[CrossRef]
  6. Mumford J, Li X, Hu F, et al. (1995) Human exposure and dosimetry of polycyclic aromatic hydrocarbons in urine from Xuan Wei, China, with high lung cancer mortality associated with exposure to unvented coal smoke. Carcinogenesis 16:3031–6.[Abstract/Free Full Text]
  7. Smith K and Liu Y. (1994) Indoor air pollution in developing countries. In Samet J (Ed.). The epidemiology of lung cancer(Marcel Dekker, New York, NY) pp. 151–84.
  8. Manual J. (1999) A healthy home environment? Environ Health Perspect 107:A352–7.[Web of Science][Medline]
  9. Agence de la sante et des sociaux de Montreal (Health and Social Services Agency of Montreal). Residential wood heating in urban areas: let's reduce emissions. Montreal. Canada: 2005 (www.santepub-mtl.qc.ca/Environnement/chauffage/pdf/heating2005.pdf). (Accessed July 2006).
  10. Gérin M, Siemiatycki J, Kemper H, et al. (1985) Obtaining occupational exposure histories in epidemiologic case-control studies. J Occup Med 27:420–6.[Web of Science][Medline]
  11. World Health Organization/International Agency for Research on Cancer. (1998) Histological groups for comparative studies. (International Agency for Research on Cancer, Lyon, France) (Technical report no. 31).
  12. Statistical methods in cancer research. The analysis of case-control studies. IARC scientific publication no. 32 (1980) (International Agency for Research on CancerIn Breslow NE and Day NE (Eds.). , Lyon, France) Vol I:248–79.
  13. Leffondré K, Abrahamowicz M, Siemiatycki J. (2002) Modeling smoking history: a comparison of different approaches. Am J Epidemiol 156:813–23.[Abstract/Free Full Text]
  14. Stata Corporation. (1993) Statistics software, release 8.1. (Stata Corporation, Santa Monica, CA).
  15. Srivastava PK, Pandit GG, Sharma S, et al. (2000) Volatile organic compounds in indoor environments in Mumbai, India. Sci Total Environ 255:161–8.[CrossRef][Medline]
  16. Balakrishnan K, Sankar S, Parikh J, et al. (2002) Daily average exposures to respirable particulate matter from combustion of biomass fuels in rural households of southern India. Environ Health Perspect 110:1069–75.[Web of Science][Medline]
  17. Moriske HJ, Drews M, Ebert G, et al. (1996) Indoor air pollution by different heating systems: coal burning, open fireplace and central heating. Toxicol Lett 88:349–54.[CrossRef][Web of Science][Medline]
  18. Leaderer BP, Zagraniski RT, Berwick M, et al. (1986) Assessment of exposure to indoor air contaminants from combustion sources: methodology and application. Am J Epidemiol 124:275–89.[Abstract/Free Full Text]
  19. Pandit GG, Srivastava PK, Rao AM. (2001) Monitoring of indoor volatile organic compounds and polycyclic aromatic hydrocarbons arising from kerosene cooking fuel. Sci Total Environ 279:159–65.[CrossRef][Medline]
  20. Levesque B, Allaire S, Gauvin D, et al. (2001) Wood-burning appliances and indoor air quality. Sci Total Environ 281:47–62.[CrossRef][Medline]
  21. Zhang Y, Chen BS, Liu GQ, et al. (2003) Natural gas and indoor air pollution: a comparison with coal gas and liquefied petroleum gas. Biomed Environ Sci 16:227–36.[Web of Science][Medline]
  22. Pandey MR, Boleij JS, Smith KR, et al. (1989) Indoor air pollution in developing countries and acute respiratory infection in children. Lancet 1:427–9.[Web of Science][Medline]
  23. Smith KR. (2002) Indoor air pollution in developing countries: recommendations for research. Indoor Air 12:198–207.[CrossRef][Web of Science][Medline]
  24. Baris E and Ezzati M. (2004) Should interventions to reduce respirable pollutants be linked to tuberculosis control programs? BMJ 329:1090–3.[Free Full Text]
  25. WorldHealth Organization. Addressing the links between indoor air pollution, household energy and human health. Based on the WHO-USAID global consultation on the health impact of indoor air pollution and household energy on developing countries. (Meeting report). Washington, DC, 2000. (http://www.who.int/mediacentre/events/HSD_Plaq_10.pdf).
  26. World Health Organization. (2002) The world health report: reducing risks, promoting healthy life. (WHO, Geneva, Switzerland).
  27. Shrestha IL and Shrestha SL. (2005) Indoor air pollution from biomass fuels and respiratory health of the exposed population in Nepalese households. Int J Occup Environ Health 11:150–60.[Web of Science][Medline]
  28. Ekici A, Ekici M, Kurtipek E, et al. (2005) Obstructive airway diseases in women exposed to biomass smoke. Environ Res 99:93–8.[Medline]
  29. Dietz A, Senneweld E, Maier H. (1995) Indoor air pollution by emissions of fossil fuel single stoves: possibly a hitherto underrated risk factor in the development of carcinomas in the head and neck. Otolaryngol Head Neck Surg 112:308–15.[CrossRef][Web of Science][Medline]
  30. Pintos J, Franco EL, Kowalski LP, et al. (1998) Use of wood stoves and risk of cancers of the upper aero-digestive tract: a case-control study. Int J Epidemiol 27:936–40.[Abstract/Free Full Text]
  31. Mulford JL, He XZ, Chapman RS, et al. (1987) Lung cancer and indoor air pollution in Xuam Wei, China. Science 235:217–20.[Abstract/Free Full Text]
  32. Mulford JL, Champman RS, Harris DB, et al. (1989) Indoor air exposure to coal and wood combustion emissions associated with high lung cancer rate in Xuan Wei, China. Environ Int 15:315–20.[CrossRef]
  33. Sobue T. (1990) Association of indoor air pollution and lifestyle with lung cancer in Osaka, Japan. Int J Epidemiol 19:S62–6.[Abstract]
  34. Liu Q, Sasco AJ, Riboli E, et al. (1993) Indoor air pollution and lung cancer in Guangzhou, Peoples Republic of China. Am J Epidemiol 137:145–54.[Abstract/Free Full Text]
  35. Ko YC, Lee CH, Chen MJ, et al. (1997) Risk factors for primary lung cancer among non-smoking women in Taiwan. Int J Epidemiol 26:24–31.[Abstract/Free Full Text]
  36. Zhong L, Goldberg MS, Parent ME, et al. (1999) Risk of developing lung cancer in relation to exposure to fumes from Chinese-style cooking. Scand J Work Environ Health 25:309–16.[Web of Science][Medline]
  37. Lan Q, Chapman RS, Schreinemachers DM, et al. (2002) Household stove improvement and risk of lung cancer in Xuanwei, China. J Natl Cancer Inst 94:826–35.[Abstract/Free Full Text]
  38. Behera D and Balamugesh T. (2005) Indoor air pollution as a risk factor for lung cancer in women. J Assoc Physicians India 53:190–2.[Medline]
  39. Kleinerman RA, Wang Z, Wang L, et al. (2002) Lung cancer and indoor exposure to coal and biomass in rural China. J Occup Environ Med 44:338–44.[Web of Science][Medline]
  40. Wu AH, Henderson BE, Pike MC, et al. (1985) Smoking and other risk factors for lung cancer in women. J Natl Cancer Inst 74:747–51.[Web of Science][Medline]
  41. Lissowska J, Bardin-Mikolajczak A, Fletcher T, et al. (2005) Lung cancer and indoor pollution from heating and cooking with solid fuels: the IARC international multicentre case-control study in Eastern/Central Europe and the United Kingdom. Am J Epidemiol 162:326–33.[Abstract/Free Full Text]
  42. Tobacco smoke and involuntary smoking. IARC monographs on the evaluation of carcinogenic risks to humans. Vol 83 (2004) (International Agency for Research on Cancer, Lyon, France) 83: pp. 1–1438.

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