Chinese food cooking and lung cancer in women nonsmokers

Cigarette smoking cannot fully explain the epidemiologic characteristics of lung cancer in Taiwanese women, who smoke rarely but have lung cancer relatively often. In a previous study, the authors suspected that exposure to fumes from cooking oils was an important risk factor for lung cancer in Taiwanese women nonsmokers in the Republic of China. In a new case-control study conducted in 1993-1996, they further explored the association of oil fumes with lung cancer in women. Two sets of controls were used concurrently. The subjects were 131 nonsmoking incident cases with newly diagnosed and histologically confirmed primary carcinoma of the lung, 252 hospital controls hospitalized for causes unrelated to diseases of smoking, and 262 community controls; all controls were women nonsmokers matched by age and date of interview. Details on cooking conditions and habits were collected, in addition to other epidemiologic data. Lung cancer risk increased with the number of meals per day to about threefold for women who cooked these meals each day. The risk was also greater if women usually waited until fumes were emitted from the cooking oil before they began cooking (adjusted odds ratios = 2.0-2.6) and if they did not use a fume extractor (adjusted odds ratios = 3.2-12.2). These results suggest that a proportion of lung cancer may be attributable to the habit of waiting until the cooking oil has been heated to a high temperature before cooking the food.     

非吸烟女性肺癌发病危险因素的Meta分析

目的：综合评价我国非吸烟女性肺癌发病的危险因素。方法：应用Meta分析方法对国内7篇有关非吸烟女性肺癌危险因素的病例对照研究进行定量综合分析,共累积病例1115例,对照1520例。统计处理采用Meta分析的随机效应模型。结果：肺部疾病史、家庭肺癌史、油烟污染、煤烟污染、被动吸烟等5个研究因素的合并比值比（OR值）分别是2.87、2.79、2.52、1.42和1.64进一步分层研究提示随着油烟污染程度的加重,其OR值也有明显的上升。结论：家庭肺癌史、肺部疾病史、油烟污染、煤烟污染等因素可能与非吸烟女性肺癌的发生有关,被动吸烟的作用尚不能肯定。     

Lung cancer and indoor exposure to coal and biomass in rural China

Incomplete combustion of coal in homes has been linked with lung cancer in China. We report on a lung cancer case-control study in a rural area of China, where many residents live in underground dwellings and burn coal and unprocessed biomass (crop residues, wood, sticks, and twigs) for heating and cooking. We interviewed 846 patients with lung cancer (626 men, 220 women; aged 30 to 75 years) diagnosed between 1994 and 1998, and 1740 population-based controls. The odds ratio for lung cancer associated with coal use compared with that for biomass in the house of longest residence was 1.29 (95% confidence interval, 1.03 to 1.61), adjusted for smoking and socioeconomic status. The risk for lung cancer increased relative to the percentage of time that coal was used over the past 30 years (P = 0.02). Our findings suggest that coal may contribute to the risk of lung cancer in this rural area of China.     

Lung Cancer in Chinese Women: Evidence for an Interaction between Tobacco Smoking and Exposure to Inhalants in the Indoor Environment

Background

Epidemiologic data suggest that Chinese women have a high incidence of lung cancer in relation to their smoking prevalence. In addition to active tobacco smoke exposure, other sources of fumes and airborne particles in the indoor environment, such as cooking and burning of incense and mosquito coils, have been considered potential risk factors for lung cancer.

Objectives

We used a case–control study to explore effects of inhalants from combustion sources common in the domestic environment on lung cancer and their modification by active tobacco smoking.

Methods

We analyzed 703 primary lung cancer cases and 1,578 controls. Data on demographic background and relevant exposures were obtained by face-to-face interviews in the hospital.

Results

We observed a positive relationship with daily exposure to incense or mosquito coils and to cooking fumes only among smokers, and no association among lifetime nonsmokers. Interactions between smoking and frequency of cooking, or exposure to incense or mosquito coils were statistically significant and consistent with synergistic effects on lung cancer. The odds ratio (OR) comparing smokers without daily incense or mosquito coil exposure with nonsmokers without daily exposure was 2.80 [95% confidence interval (CI), 1.86–4.21], whereas the OR comparing smokers with daily exposure to the same referent group was 4.61 (95% CI, 3.41–6.24). In contrast, daily exposure to incense or mosquito coils was not associated with lung cancer among nonsmokers (OR = 0.91; 95% CI, 0.72–1.16). We observed the same pattern of associations for smokers without (OR = 2.31; 95% CI, 1.52–3.51) and with (OR = 4.50; 95% CI, 3.21–6.30) daily cooking exposure compared with nonsmokers, with no evidence of an association with daily cooking exposure among nonsmokers.

Conclusion

Our results suggest that active tobacco smoking not only is an important risk factor for development of lung cancer, but also may cause smokers to be more susceptible to the risk-enhancing effects of other inhalants.     

Serum carotenoids are associated with increased lung cancer risk among alcohol drinkers, but not among non-drinkers in a cohort of tin miners

To examine the association between pre-diagnostic serum carotenoid levels and lung cancer risk and the effects of alcohol intake on the carotenoid-lung cancer relationship, we conducted a case-control study in an occupational cohort from the Yunnan Tin Corporation in China. During 6 years of follow-up, 339 cases of confirmed lung cancer were diagnosed. Among these cases, those who donated pre-diagnostic blood (n = 108) were eligible for this study. For each case, two individuals alive and free of cancer at the time of case diagnosis, matched on age, sex, and date of blood collection, were selected as controls. Serum beta-carotene (odds ratios (ORs) for tertiles: 1, 1.3, 2.0) and beta-cryptoxanthin (ORs for tertiles: 1, 1.8, 2.9) levels were positively associated with lung cancer risk after adjustment for tobacco use and radon exposure. Among alcohol drinkers, higher serum carotenoid levels were significantly associated with increased lung cancer risk (alpha-carotene OR 2.2, 95% confidence interval (CI) 1.1-4.4, beta-carotene OR 7.6, 95% CI 3.1-18.6, lutein/zeaxanthin OR 2.3, 95% CI 1.2-6.6 and beta-cryptoxanthin OR 7.6, 95% CI 2.7-21.5). Conversely, risk estimates among non-drinkers suggest a possible protective association for higher carotenoid levels.     

Occupational risks for laryngeal cancer: a case-control study

The most solidly established risk factors for laryngeal cancer are tobacco and alcohol. As for occupational factors, the only established carcinogen is exposure to strong inorganic acid mists. However, asbestos, pesticides, paints, gasoline, diesel engine emissions, dusts, and other factors have been reported in the literature as occupational agents that increase the risk of laryngeal cancer. A hospital-based case-control study was conducted to investigate occupational risk factors for laryngeal cancer. Detailed data on smoking, alcohol consumption, and occupational history were collected for 122 laryngeal cancers and 187 controls matched by frequency (according to sex and age). Laryngeal cancer was associated with exposure to respirable free crystalline silica (OR = 1.83; 95%CI: 1.00-3.36), soot (from coal, coke, fuel oil, or wood) (odds ratio - OR = 1.78; 95% confidence interval - 95%CI: 1.03-3.03), fumes (OR = 2.55; 95%CI: 1.14-5.67), and live animals (OR = 1.80; 95%CI: 1.02-3.19).     

In-Home Coal and Wood Use and Lung Cancer Risk: A Pooled Analysis of the International Lung Cancer Consortium

Background

Domestic fuel combustion from cooking and heating is an important public health issue because roughly 3 billion people are exposed worldwide. Recently, the International Agency for Research on Cancer classified indoor emissions from household coal combustion as a human carcinogen (group 1) and from biomass fuel (primarily wood) as a probable human carcinogen (group 2A).

Objectives

We pooled seven studies from the International Lung Cancer Consortium (5,105 cases and 6,535 controls) to provide further epidemiological evaluation of the association between in-home solid-fuel use, particularly wood, and lung cancer risk.

Methods

Using questionnaire data, we classified subjects as predominant solid-fuel users (e.g., coal, wood) or nonsolid-fuel users (e.g., oil, gas, electricity). Unconditional logistic regression was used to estimate the odds ratios (ORs) and to compute 95% confidence intervals (CIs), adjusting for age, sex, education, smoking status, race/ethnicity, and study center.

Results

Compared with nonsolid-fuel users, predominant coal users (OR = 1.64; 95% CI, 1.49–1.81), particularly coal users in Asia (OR = 4.93; 95% CI, 3.73–6.52), and predominant wood users in North American and European countries (OR = 1.21; 95% CI, 1.06–1.38) experienced higher risk of lung cancer. The results were similar in never-smoking women and other subgroups.

Conclusions

Our results are consistent with previous observations pertaining to in-home coal use and lung cancer risk, support the hypothesis of a carcinogenic potential of in-home wood use, and point to the need for more detailed study of factors affecting these associations.     

Relation of radon exposure and tobacco use to lung cancer among tin miners in Yunnan Province, China

We studied the relation of radon exposure and tobacco use to lung cancer among tin miners in Yunnan Province in the People's Republic of China. Interviews were conducted in 1985 with 107 living tin miners with lung cancer and an equal number of age-matched controls from among tin miners without lung cancer to obtain information on lung cancer risk factors including a detailed history of employment and tobacco use. Occupational history was combined with extensive industrial hygiene data to estimate cumulative working level months (WLM) of radon daughter exposure. Similar data were also used to estimate arsenic exposure for control in the analysis. Results indicate an increased risk of lung cancer for water pipe smoking, a traditional form of tobacco use practiced in 91% of cases and 85% of controls. Ever use of water pipes was associated with a twofold elevation in risk when compared with tobacco abstainers, and a dose-response relation was observed with increasing categories of pipe-year (dose times duration) usage. Estimated WLM of radon exposure varied from 0 to 1,761 among subjects but averaged 515 in cases versus only 244 in controls. Analyses indicated that the persons in the highest quarter of the radon exposure distribution had an odds ratio (OR) = 9.5 (95% confidence interval = 2.7-33.1) compared to persons without radon exposure after controlling for arsenic exposure and other potential confounders. Examination of duration and rate of radon exposure indicated higher risk associated with long duration as opposed to high rate of exposure. Cross-categorizations of radon exposure and tobacco use suggest greater risk associated with radon exposure than tobacco in these workers.     

445对肺癌病例对照的危险因素分析

目的 探讨人群中肺癌的危险因素。方法 应用病例对照的方法．收集广州市l998—2001年部分新诊断的原发性肺癌病例445例。按性别、年龄1：1配对选取正常对照，用由245个项目组成的问卷调查病例和对照有关危险因素的暴露史，通过单因素分析和多因素条件Logistic回归分析筛选肺癌的主要危险因素。结果 经单因素分析发现35个暴露因素与肺癌发生有关。多因素分析发现肺癌有9个主要危险因素和1个保护因素。它们是：吸烟,OR及95％可信区间为3．19(2.18,4.67)；被动吸烟来源于父亲，OR为2.88(1．64，5．04)；被动吸烟来源于配偶，OR为2．73(1．32,5.66)；肺结核病史，OR为2.36(1．13，4.94)；家庭用煤为燃料。OR为3．44(1.38，8．57)；常食用腌、酸菜．OR为3.83(2．34,6．27)；常食用咸鱼，OR为4.49(2.86，7．06)；经常下厨用猛火炒菜，OR为4.45(3.03，6．56)；职业接触金属类毒物。OR为8．76(2．28，33．64)。经常体育锻炼OR为0．59(0．33，1．06)。可能是一个候选的保护因素，P＝0.075。按细胞类型分层．发现肺鳞癌的危险因素与肺腺癌的危险因素有较大差别。结论 肺癌的发生与多种环境危险因素的暴露有关，不同细胞类型肺癌的危险因素也有所差异。从肺癌的病因学来看，它是可以预防与控制的。     

Occupation and lung cancer in Shanghai: a case-control study

Occupation was evaluated as a potential risk factor for lung cancer as part of a large population based case-control study conducted in the ten urban districts of Shanghai. A total of 733 newly diagnosed cases of male lung cancer and 760 controls selected from the general population was interviewed to obtain lifetime occupational histories and information on smoking and other factors. Of the approximately 25 major industrial titles examined, significantly raised risks, adjusted for smoking, were found for employment in agricultural production (odds ratio (OR) = 1.6, 95% confidence interval (CI) = 1.0-2.6). A concomitant increase was detected for farmers (OR = 1.6, 95% CI = 1.0-2.5) when 35 major occupational titles were examined. There was a 70% excess among workers in the chemical industry (OR = 1.7, 95% CI = 0.9-3.1) and a significant decrease among textile industry workers (OR = 0.7, 95% CI = 0.5-1.0). Raised risks of 30% to 80% were associated with reported job exposures to wood and coal dusts, smoke from burning fuels, and chemical fumes. Employment categories were also examined for 672 cases and 735 controls among women, but small numbers in many of the industrial and occupational categories precluded detailed analyses. The largest excess risk among women (OR = 5.1, 95% CI 1.3-23.5) was among glass products workers. Although cigarette smoking was the dominant cause of lung cancer among men and a significant risk factor among women in Shanghai, these findings suggest the importance of certain workplace exposures and offer leads to occupational carcinogens.     

Occupation and lung cancer in Shanghai: a case-control study.

Occupation was evaluated as a potential risk factor for lung cancer as part of a large population based case-control study conducted in the ten urban districts of Shanghai. A total of 733 newly diagnosed cases of male lung cancer and 760 controls selected from the general population was interviewed to obtain lifetime occupational histories and information on smoking and other factors. Of the approximately 25 major industrial titles examined, significantly raised risks, adjusted for smoking, were found for employment in agricultural production (odds ratio (OR) = 1.6, 95% confidence interval (CI) = 1.0-2.6). A concomitant increase was detected for farmers (OR = 1.6, 95% CI = 1.0-2.5) when 35 major occupational titles were examined. There was a 70% excess among workers in the chemical industry (OR = 1.7, 95% CI = 0.9-3.1) and a significant decrease among textile industry workers (OR = 0.7, 95% CI = 0.5-1.0). Raised risks of 30% to 80% were associated with reported job exposures to wood and coal dusts, smoke from burning fuels, and chemical fumes. Employment categories were also examined for 672 cases and 735 controls among women, but small numbers in many of the industrial and occupational categories precluded detailed analyses. The largest excess risk among women (OR = 5.1, 95% CI 1.3-23.5) was among glass products workers. Although cigarette smoking was the dominant cause of lung cancer among men and a significant risk factor among women in Shanghai, these findings suggest the importance of certain workplace exposures and offer leads to occupational carcinogens.     

Lung cancer and indoor air pollution arising from Chinese-style cooking among nonsmoking women living in Shanghai, China.

Associations between indoor air pollution from Chinese-style cooking and lung cancer have been found in several investigations. To provide more detailed estimates of the associations while accounting for key confounding factors, we conducted a population-based, case-control study of lung cancer among nonsmoking women living in Shanghai, the People's Republic of China. Five hundred four incident, primary lung cancer cases diagnosed from February 1992 through January 1994 were identified through the population-based Shanghai Cancer Registry. A control group of 601 nonsmoking women was selected randomly from the Shanghai-Residential Registry, and they were frequency-matched to the expected age distribution of the cases. Exposure to indoor air pollutants from Chinese-style cooking was ascertained through in-person interviews. We estimated adjusted odds ratios (OR) and 95% confidence intervals (CI) by unconditional logistic regression. There were similar patterns of excess risk for exposure to indoor air pollutants from Chinese-style cooking across different histological types of lung cancer. Women who did not have a separate kitchen experienced a 28% increased risk of lung cancer (OR = 1.28; 95% CI = 0.98-1.68). We found little association with area of the windows of the apartment where subjects had lived for the longest period of time. Heating cooking oils to high temperatures was associated with a 1.64-fold increased risk of lung cancer (95% CI = 1.24-2.17). An 84% excess risk was found among women who most often cooked with rapeseed oil (OR = 1.84; 95% CI = 1.12-3.02). Lung cancer risks were also related to "considerable" smokiness of the kitchen during cooking (OR = 2.38; 95% CI = 1.58-3.57), frequent eye irritation during cooking (OR = 1.68; 95% CI = 1.02-2.78), to a more than weekly use of frying (OR = 2.09; 95% CI = 1.14-3.84) and deep-frying (OR = 1.88; 95% CI = 1.06-3.32). This population-based case-control study confirmed that exposure to indoor air pollution from Chinese-style cooking, especially cooking unrefined rapeseed oil at high temperatures in woks, may increase the risk of lung cancer.     

Environmental and Dietary Factors and Lung Cancer Risk Among Chinese Women: A Case-Control Study in Southeast China

After decades of increase, lung cancer has become the leading cause of cancer death among women. The mortality rate from lung cancer is ascending at a relatively steady rate, which has greatly affected the health of the female population and become a serious issue. A case-control study of 226 female lung cancer cases and 269 controls was conducted from 2006 to 2010 in Fujian Province. A structured questionnaire was used to gather information on demographic characteristics as well as dietary and environmental factors. Odds ratios and 95% confidence intervals were estimated by using univariate logistic regression. Multivariate unconditional logistic regression analysis was applied to evaluate the potential interactions of variables or confounders. The consumption of fruit, eggs, and tea was inversely associated with the risk of lung cancer. As expected, cooking oil fumes and environmental tobacco exposure were positively associated with elevated risk. In addition, frequent physical activity and late age at menarche were identified as protective factors of female lung cancer. The results demonstrate that some environmental and dietary factors are related to the risk of lung cancer among the female population in southeast China.     

Environmental and dietary factors and lung cancer risk among Chinese women: a case-control study in southeast China

After decades of increase, lung cancer has become the leading cause of cancer death among women. The mortality rate from lung cancer is ascending at a relatively steady rate, which has greatly affected the health of the female population and become a serious issue. A case-control study of 226 female lung cancer cases and 269 controls was conducted from 2006 to 2010 in Fujian Province. A structured questionnaire was used to gather information on demographic characteristics as well as dietary and environmental factors. Odds ratios and 95% confidence intervals were estimated by using univariate logistic regression. Multivariate unconditional logistic regression analysis was applied to evaluate the potential interactions of variables or confounders. The consumption of fruit, eggs, and tea was inversely associated with the risk of lung cancer. As expected, cooking oil fumes and environmental tobacco exposure were positively associated with elevated risk. In addition, frequent physical activity and late age at menarche were identified as protective factors of female lung cancer. The results demonstrate that some environmental and dietary factors are related to the risk of lung cancer among the female population in southeast China.     

珠海市部分人群肺癌危险因素病例对照分析

目的探讨珠海市人群肺癌的相关危险因素。方法采用1：1配对的病例对照研究方法,选取肺癌死亡个案及对照各131例,调查其一般情况、生活居住环境、工作环境、饮食习惯、生活方式、健康和精神状况等与肺癌有关的7个方面,对疾病史、肿瘤家族史、吸烟、被动吸烟、饮酒、煤炉使用年限、房屋通风、职业史、居住地点和工作时间等45个因素采用条件logistic回归方法进行单因素和多因素分析,筛选主要危险因素：结果多因素logistic回归分析显示,吸烟（OR=2．309）、肿瘤家族史（OR=3．348）、厨房油烟大（OR：3．726）、房子通风差（OR=7．989）与肺癌死亡有关（P〈0．05）：剂量-反应分析显示吸烟与肺癌发病呈荆量反应关系（P〈0．05）,吸烟少于10支、10～19支、20～40支组的OR值分别为3．250、2．158、3．431。结论吸烟、肿瘤家族史、厨房油烟大、房子通风差可能是珠海市部分人群肺癌主要危险因素：加强控烟和改善居住环境是预防肺癌的重要措施。     

非吸烟女性肺癌发病危险因素的Meta分析

目的：综合评价我国非吸烟女性肺癌发病的危险因素。方法：应用Meta分析方法对国内6个有关非吸烟女性肺癌危险因素的病例对照研究进行定量综合分析,共累积病例915例,对照1321例。统计处理采用Meta分析的随机效应模型。结果：肺部疾病史、家族肺癌史、油烟污染、煤烟污染、被动吸烟等5个研究 因素的合并OR值分别是2．87、2．79、2．51、1．42和1．29,进一步分层研究显示随着油烟污染程度的加重,其OR值也有明显的上升。结论：家族肺癌史、肺部疾病史、油烟污染、煤煨污染等因素可能与非吸烟女性肺癌的发生有关,被动吸烟的作用尚不能肯定。     

A case-control study of malignant and non-malignant respiratory disease among employees of a fiberglass manufacturing facility. II. Exposure assessment.

A case-control study of malignant and non-malignant respiratory disease among employees of the Owens-Corning Fiberglas Corporation's Newark, Ohio plant was undertaken. The aim was to determine the extent to which exposures to substances in the Newark plant environment, to non-workplace factors, or to a combination may play a part in the risk of mortality from respiratory disease among workers in this plant. A historical environmental reconstruction of the plant was undertaken to characterise the exposure profile for workers in this plant from its beginnings in 1934 to the end of 1987. The exposure profile provided estimates of cumulative exposure to respirable fibres, fine fibres, asbestos, talc, formaldehyde, silica, and asphalt fumes. Employment histories from Owens-Corning Fiberglas provided information on employment characteristics (duration of employment, year of hire, age at first hire) and an interview survey obtained information on demographic characteristics (birthdate, race, education, marital state, parent's ethnic background, and place of birth), lifetime residence, occupational and smoking histories, hobbies, and personal and family medical history. Matched, unadjusted odds ratios (ORs) were used to assess the association between lung cancer or non-malignant respiratory disease and the cumulative exposure history, demographic characteristics, and employment variables. Only the smoking variables and employment characteristics (year of hire and age at first hire) were statistically significant for lung cancer. For non-malignant respiratory disease, only the smoking variables were statistically significant in the univariate analysis. Of the variables entered into a conditional logistic regression model for lung cancer, only smoking (smoked for six months or more v never smoked: OR = 26.17, 95% confidence interval (95% CI) 3.316-206.5) and age at first hire (35 and over v less than 35: OR = 0.244, 95% CI 0.083-0.717) were statistically significant. There were, however, increased ORs for year of employment (first hired before 1945 v first hire after 1945: OR = 1.944, 95% CI 0.850-4.445), talc (cumulative exposure >1000 fibres/ml days v never exposed: OR = 1.355, 95% CI 0.407-5.515), and asphalt fumes (cumulative exposure >0.01 mg/m(3) days v never exposed: OR 1.131, 95% CI 0.468-2.730). For non-malignant respiratory disease, only the smoking variable was significant in the conditional logistic regression analysis (OR = 2.637, 95% CI 1.146-6.069). There were raised ORs for the higher cumulative exposure categories for respirable fibres, asbestos, silica, and asphalt fumes. For both silica and asphalt fumes, ORs were more than double the reference groups for all exposure categories. A limited number of subjects were exposed to fine fibres. The scarcity of cases and controls limits the extent to which analyses for fine fibre may be carried out. Within those limitations, among those who had worked with fine fibre, the unadjusted, unmatched OR for lung cancer was (1.0 (95% CI 0.229-4.373) and for non-malignant respiratory disease, the OR was 1.5 (95% CI 0.336-6.702). The unadjusted OR for lung cancer for exposure to fine fibre was consistent with that for all respirable fibre and does not suggest an association. For non-malignant respiratory disease, the unadjusted OR for fine fibre was opposite in direction from that for all respirable fibres. Within the limitations of the available data on fibre, there is o suggestion that exposure to fine fibre has resulted in an increase in risk of lung cancer. The increased OR for non-malignant respiratory disease is inconclusive. The results of this population, in this place and time, neither respirable fibres nor any of the substances investigated as part of the plant environment are statistically significant factors for lung cancer risk although there are increased ORs for exposure to talc and asphalt fumes. Smoking is the most important factors in risk for lung cancer in this population. The situation is less clear for non-malignant respiratory disease. Unlike lung cancer, non-malignant respiratory represents a constellation of outcomes and not a single well defined end point. Although smoking was the only statistically significant factor for non-malignant respiratory disease in this analysis, the ORs for respirable fibres, asbestos, silica, and asphalt fumes were greater than unity for the highest exposure categories. Although the raised ORs for these substances may represent the results of a random process, they may be suggestive of an increased risk and require further investigation.     

Smoking and other risk factors for lung cancer in Xuanwei, China

In Xuanwei County, Yunnan Province, lung cancer mortality rates are among the highest in China in both males and females. Previous studies have shown a strong association of lung cancer mortality with indoor air pollution from 'smoky' coal combustion. In the present case-control study, 110 newly-diagnosed lung cancer patients and 426 controls were matched with respect to age, sex, occupation (all subjects were farmers), and village of residence (which provided matching with respect to fuel use). This design allowed assessment of known and suspected lung cancer risk factors other than those mentioned above. Data from males and females were analysed by conditional logistic regression. In females who do not smoke, the presence of lung cancer was statistically significantly associated with chronic bronchitis (odds ratio [OR] = 7.37, 95% confidence interval [Cl]: 2.40-22.66) and family history of lung cancer (OR 4.18, 95% Cl: 1.61-10.85). Females' results also suggested an association of lung cancer with duration of cooking food (OR 1.00, 9.18 and 14.70), but not with passive smoking (OR 0.77, 95% Cl: 0.30-1.96). In males, lung cancer was significantly associated with chronic bronchitis (OR 7.32, 95% Cl: 2.66-20.18), family history of lung cancer (OR 3.79, 95% Cl: 1.70-8.42), and personal history of cooking food (OR 3.36, 95% Cl: 1.27-8.88). In males a dose-response relationship of lung cancer with smoking index (years of smoking*amount of smoking) was shown by risks of 1.00, 2.61, 2.17 and 4.70.     

Prevalence of acute respiratory infections in women and children in Western Sierra Leone due to smoke from wood and charcoal stoves

Combustion of biomass fuels (wood and charcoal) for cooking releases smoke that contains health damaging pollutants. Women and children are the most affected. Exposure to biomass smoke is associated with acute respiratory infections (ARI). This study investigated the prevalence of ARI potentially caused by smoke from wood and charcoal stoves in Western Sierra Leone, as these two fuels are the predominant fuel types used for cooking. A cross sectional study was conducted for 520 women age 15-45 years; and 520 children under 5 years of age in homes that burn wood and charcoal. A questionnaire assessing demographic, household and exposure characteristics and ARI was administered to every woman who further gave information for the child. Suspended particulate matter (SPM) was continuously monitored in fifteen homes. ARI prevalence revealed 32% and 24% for women, 64% and 44% for children in homes with wood and charcoal stoves, respectively. After adjusting for potential confounders for each group, the odds ratio of having suffered from ARI was similar for women, but remained large for children in homes with wood stoves relative to charcoal stoves (OR = 1.14, 95%CI: 0.71-1.82) and (OR = 2.03, 95%CI: 1.31-3.13), respectively. ARI prevalence was higher for children in homes with wood stoves compared with homes with charcoal stoves, but ARI prevalence for both types of fuels is higher compared with reported prevalence elsewhere. To achieve a reduction in ARI would require switching from wood and charcoal to cleaner fuels.     

A case-referent study of lung cancer and incense smoke, smoking, and residential radon in Chinese men

Background: Burning incense generates large amounts of air pollutants, many of which are confirmed or suspected human lung carcinogens.Objectives: We conducted a population-based case-referent study to examine the effect of incense smoke exposure on lung cancer risk among Chinese males and explored the joint effect of cigarette smoking and exposure to residential radon.Methods: We recruited 1,208 male lung cancer incident cases and 1,069 community referents from 2004 to 2006 and estimated their lifetime exposures to incense smoke and other residential indoor air pollutants based on self-reported information collected during interviews. We performed unconditional multivariable logistic regression analysis to estimate the odds ratio (OR) for lung cancer associated with exposure to incense smoke after adjusting for possible confounders. We conducted stratified analyses by smoking status and exposures to incense burning and residential radon and explored the potential additive-scale interactions.Results: We observed an association between incense exposure and lung cancer that was limited primarily to smokers. Cigarette smoking and high cumulative incense exposure at home appeared to have a synergistic effect on lung cancer (compared with never-smokers who never used incense, the OR for lung cancer for smokers who used incense ≥ 60 day-years = 5.00; 95% confidence interval: 3.34, 7.51). Power was limited, but we also found preliminary evidence suggesting that radon exposure may increase risk among smokers using incense.Conclusion: Our study suggests that exposure to incense smoke in the home may increase the risk of lung cancer among smokers and that exposure to radon may further increase risk.