Worker's Pneumoconiosis Research Articles

Coal Mine Dust Desquamative Chronic Interstitial Pneumonia: A Precursor of Dust-Related Diffuse Fibrosis and of Emphysema.

Background:Diseases associated with coal mine dust continue to affect coal miners. Elucidation of initial pathological changes as a precursor of coal dust-related diffuse fibrosis and emphysema, may have a role in treatment and prevention. Objective:To identify the precursor of dust-related diffuse fibrosis and emphysema. Methods:Birefringent silica/silicate particles were counted by standard microscope under polarized light in the alveolar macrophages and fibrous tissue in 25 consecutive autopsy cases of complicated coal worker's pneumoconiosis and in 21 patients with tobacco-related respiratory bronchiolitis. Results:Coal miners had 331 birefringent particles/high power field while smokers had 4 (p<0.001). Every coal miner had intra-alveolar macrophages with silica/silicate particles and interstitial fibrosis ranging from minimal to extreme. All coal miners, including those who never smoked, had emphysema. Fibrotic septa of centrilobular emphysema contained numerous silica/silicate particles while only a few were present in adjacent normal lung tissue. In coal miners who smoked, tobacco-associated interstitial fibrosis was replaced by fibrosis caused by silica/silicate particles. Conclusion:The presence of silica/silicate particles and anthracotic pigment-laden macrophages inside the alveoli with various degrees of interstitial fibrosis indicated a new disease: coal mine dust desquamative chronic interstitial pneumonia, a precursor of both dust-related diffuse fibrosis and emphysema. In studied coal miners, fibrosis caused by smoking is insignificant in comparison with fibrosis caused by silica/silicate particles. Counting birefringent particles in the macrophages from bronchioalveolar lavage may help detect coal mine dust desquamative chronic interstitial pneumonia, and may initiate early therapy and preventive measures.

HSP70 gene polymorphism on genetic susceptibility to the coal worker's penumoconiosis of han nationality in Xinjiang, China.

Objective: To explore the influence of heat shock protein 70 (HSP70) gene genetic susceptibility of coal worker's pneumoconiosis among the han nationality in xinjiang. Methods: 156 coal worker's pneumoconiosis patients and 96 mine workers were randomly selected from the han coal worker's pneumoconiosis patients and attend the health check retirement mine workers from March to December, 2014 in Xinjiang Uygur Autonomous Region of Occupational Disease Hospital. Using TaqMan genotyping methods to detect HSP70 genotype distribution in the two groups. Results: The HSP70-1+190 loci GC genotype occurrence frequencies of coal worker's pneumoconiosis was significantly higher than the control group (χ2=6.75, P<0.05) , the risk of coal worker's pneumoconiosis armed with HSP70-1+190 GC genotype individual was 2.21 times of CC genotype individual (95%CI: 1.03~4.75) , and HSP70-2+1267 and HSP70-hom+2437 loci polymorphism were no significant difference between the two groups (HSP70-2+1267: χ2=3.30, P=0.19; HSP70-hom+2437: χ2=0.12, P=0.94) . Conclusion: HSP70-1+190 GC genotypes may be a susceptible genotype, the genotype individual may be more likely to suffer from coal worker's pneumoconiosis.

Profusion of Opacities in Simple Coal Worker's Pneumoconiosis Is Associated With Reduced Lung Function

A large body of evidence demonstrates dose-response relationships of cumulative coal mine dust exposure with lung function impairment and with small-opacity profusion. However, medical literature generally holds that simple coal worker's pneumoconiosis (CWP) is not associated with lung function impairment. This study examines the relationship between small-opacity profusion and lung function in US underground coal miners with simple CWP. Miners were examined during 2005 to 2013 as part of the Enhanced Coal Workers' Health Surveillance Program. Work histories were obtained, and chest radiographs and spirometry were administered. Lung parenchymal abnormalities consistent with CWP were classified according to International Labor Organization guidelines, and reference values for FEV1 and FVC were calculated using reference equations derived from the third National Health and Nutrition Examination Survey. Differences in lung function were evaluated by opacity profusion, and regression models were fit to characterize associations between profusion and lung function. A total of 8,230 miners were eligible for analysis; 269 had category 1 or 2 simple CWP. Decrements in FEV1 % predicted were nearly consistent across profusion subcategories. Clear decrements in FVC % predicted and FEV1/FVC were also observed, although these were less consistent. Controlling for smoking status, BMI, and mining tenure, each 1-unit subcategory increase in profusion was associated with decreases of 1.5% (95% CI, 1.0%-1.9%), 1.0% (95% CI, 0.6%-1.3%), and 0.6% (95% CI, 0.4%-0.8%) in FEV1 % predicted, FVC % predicted, and FEV1/FVC, respectively. We observed progressively lower lung function across the range of small-opacity profusion. These findings address a long-standing question in occupational medicine and point to the importance of medical surveillance and respiratory disease prevention in this workforce.

Patterns of pneumoconiosis mortality in Kentucky: Analysis of death certificate data.

Mortality rates associated with total pneumoconiosis, including coal worker's pneumoconiosis (CWP), have remained elevated. 2003-2013 pneumoconiosis mortality data obtained from National Center for Health Statistics and 2011-2013 Kentucky death certificates were analyzed. Total pneumoconiosis mortality rates showed significant linear decreases in West Virginia, Pennsylvania, Kentucky, and the U.S. from 2003 to 2013; Pennsylvania and Kentucky had comparable rates in 2003 but while Pennsylvania rates significantly decreased ∼3.0 deaths/million annually, Kentucky rates decreased only 0.5/million annually. Kentucky and Pennsylvania CWP fatality rates were also comparable in 2003 but while Pennsylvania rates decreased 82% over the study period, Kentucky rates decreased only 26%. Kentucky pneumoconiosis deaths primarily occurred in white Appalachian males in-hospital. Diseases leading to pneumoconiosis death were largely respiratory and cardiovascular, with autopsies rarely performed. Coal worker environmental exposure protection should be enhanced and pneumoconiosis surveillance improvements, including enhanced management of comorbid conditions like COPD, should be considered.

Gene variance in microsomal epoxide hydrolase and the susceptibility of coal workers' pneumoconiosis

To explore whether the tagging single nucleotide polymorphisms (SNPs) within EPHX1 gene were involved in the genetic susceptibility to coal worker's pneumoconiosis (CWP) by case-control study. This study consisted of 697 CWP patients and 694 controls. All the subjects were Han Chinese, underground coal miners and recruited from coal mines of Xuzhou Mining Business Group Co Ltd.. The venous blood samples were obtained from all subjects and extracted genome DNA from the isolated leucocytes. Three SNPs were selected from the HapMap and the genotyping was done by the TaqMan method with the ABI 7900HT Real Time PCR system. The Single SNP analyses showed that the genotype frequencies of EPHX1 (rs2234922) was significantly associated with decreased risk of CWP under co-dominant model (OR = 0.22, 95% CI = 0.06~0.79, P = 0.020), recessive model (OR = 0.23, 95% CI = 0.06~0.82, P = 0.023), and addictive model (OR = 0.75, 95% CI = 0.58~0.96, P = 0.022). The further stratification analysis showed that the risk of CWP will significantly decreased in non-smoking groups (OR = 0.10, 95% CI = 0.01~0.83, P = 0.033). Our results suggest that individuals with the EPHX1 (rs223492) GG genotype was associated with a dereased risk of CWP, and it has a protective effect on the developing CWP.

Global perspectives of emerging occupational and environmental lung diseases.

New technologies continue to be introduced into the workplace and the environment. These novel technologies also bring in new hazards leading to evolving patterns of established occupational and environmental diseases, as well as novel conditions never before encountered. Many of these emerging conditions have appeared in media outlets or in the literature as case reports. These sentinel cases often serve as a warning sign for subsequent outbreaks. This review will discuss environmental and occupational lung diseases and exposures from a global perspective. These diseases and exposures include environmental exposure to asbestos and lung diseases, accelerated silicosis in sandblasting jean workers, coal worker's pneumoconiosis in surface coal miners, health effects of indoor air pollution from burning of biomass fuels and exposures to heavy metals and potential health effects from hydraulic fracturing (fracking). Other emerging conditions are also discussed, including smog in developing countries, sand storms in Asia and the Middle East and respiratory illnesses from nanoparticles and man-made fibres. Clinicians must remain vigilant for potential occupational and environmental exposures, especially when evaluating patients with unusual and unique presentation, so that occupational and environmental risk factors may be identified, and monitoring and preventive measures can be implemented early.

Impairment of pulmonary function and changes in the right cardiac structure of pneumoconiotic coal workers in China.

Information on the changes of pulmonary function and the right cardiac structure in patients with coal worker's pneumoconiosis in China is very scarce. This study was performed to clarify the changes of pulmonary function and right cardiac structure in patients with coal worker's pneumoconiosis in China. Pulmonary function, pulmonary artery systolic pressure, and the right cardiac structure were evaluated by spirometry and color Doppler echocardiography. The pulmonary artery systolic pressure of patients with coal worker's pneumoconiosis was increased with disease severity. Patients with coal worker's pneumoconiosis also exhibited an impaired pulmonary function and altered right cardiac structure compared with control subjects. A significant linear correlation of the variables of pulmonary ventilation and diffusion function with the indicators of the right cardiac structure was found in patients with coal worker's pneumoconiosis in China. This study elucidated a deterioration of pulmonary function and right cardiac structure in patients with coal worker's pneumoconiosis in China.

Predicative significance of HRV and HRT to premature beat on patients with coal worker's pneumoconiosis

To determine the predicative significance of HRV and HRT to premature beat on patients with coal-worker's pneumoconiosis. 100 coal-worker's pneumoconiosis patients with premature beat (including 44 cases of occasional ventricular premature contraction and 56 cases of frequent ventricular premature contraction) were chosen as CWP group, and 50 healthy coal workers were chosen as control group. 24 h DCG was used to monitor and analyze the change of premature beat and to calculate HRV. Index: SDNN, SDANN, HFLF, HRT: TO, TS, compare HRV of CWP group and control group and the changes of HRT of both occasional and frequent ventricular premature contraction. The incidence of CWP at night (66.1%, 37 cases) is higher than that during daytime (33.9%, 19 cases), and the difference is statistically significant with P < 0.05. HRV (SDNN SDANN HF HL) indexes of CWP group are lower than control group, and the difference is statistically significant with P < 0.05. HRV indexes of control group at night are higher than that during daytime, and the difference is statistically significant with P < 0.05. Comparison of CWP group HRV indexes between day and night is statistically insignificant with P > 0.05. Compared with control group, TO of CWP group is higher while TS is lower, and the difference is statistically significant with P < 0.05. Compared with occasional ventricular premature contraction patients in CWP group, TO of frequent ventricular premature contraction patients is higher while TS is lower, and the difference is statistically significant with P < 0.05. Frequent ventricular premature contraction group in CWP group suffer from severe impaired autonomic nervous function injury, and abnormal HRV and HRT can be prognostic indicator of frequent ventricular premature contraction among coal-worker's pneumoconiosis patients.

The Evaluation and Quantification of Respirable Coal and Silica Dust Concentrations: A Task-based Approach

Silicosis and coal worker's pneumoconiosis are serious occupational respiratory diseases associated with the coal mining industry and the inhalation of respirable dusts containing crystalline silica. The purpose of this study (funded by the Mine Health and Safety Council of South Africa) was to evaluate the individual contributions of underground coal mining tasks to the respirable dust and respirable silica dust concentrations in an underground section by sampling the respirable dust concentrations at the intake and return of each task. The identified tasks were continuous miner (CM) cutting, construction, transfer of coal, tipping, and roof bolting. The respirable dust-generating hierarchy of the tasks from highest to lowest was: transfer of coal > CM right cutting > CM left cutting > CM face cutting > construction > roof bolting > tipping; and for respirable silica dust: CM left cutting > construction > transfer of coal > CM right cutting. Personal exposure levels were determined by sampling the exposures of workers performing tasks in the section. Respirable dust concentrations and low concentrations of respirable silica dust were found at the intake air side of the section, indicating that air entering the section is already contaminated. The hierarchy for personal respirable dust exposures was as follows, from highest to lowest: CM operator > cable handler > miner > roof bolt operator > shuttle car operator, and for respirable silica dust: shuttle car operator > CM operator > cable handler > roof bolt operator > miner. Dust control methods to lower exposures should include revision of the position of workers with regard to the task performed, positioning of the tasks with regard to the CM cutting, and proper use of the line curtains to direct ventilation appropriately. The correct use of respiratory protection should also be encouraged.

Pneumoconiosis and quartz content of respirable dusts in the coal mines in Zonguldak, Turkey

Coal Worker's Pneumoconiosis (CWP) is one of the most important occupational health problems in Turkish coal mining. Despite the decrease in employment and production at Turkish Hardcoal Enterprise (TTK) in the Zonguldak Basin, the occurrence of pneumoconiosis is still very high, particularly among the face workers. This study aims to evaluate the dust concentrations and quartz contents of respirable dusts in coal faces and pneumoconiosis risks related to face workers in TTK collieries. The mean respirable dust exposure experienced by the face workers was evaluated and compared with the occupational exposure limits. The data on the dust samples exhibit great variations. The quartz contents of respirable dusts were determined by a FTIR spectrophotometer. The mean respirable dust concentration in the coal faces varies from 1.6 to 14.5mg/m3 while the quartz content varies from 0.7 to 10.4%. The mean respirable dust concentrations in the coal faces in Karadon, Amasra, Armutcuk and Kozlu collieries are above the TLV (5mg/m3) of Turkey and the percentage of the measurements exceeding the TLV in the coal faces range from 25% to 100. An analysis of variance was performed to investigate the effects of workplace and seam characteristics on respirable dust levels. According to the results of variance analysis (ANOVA), it was seen that there are significant differences between seams and collieries in terms of dust concentration and quartz contents of respirable dust.CWP is still the most important problem in the collieries of TTK. The occurrence of CWP is higher among underground face workers. There have been 200 CWP cases in the last decade with a prevalence rate of 6.3%. CWP rates in the coal faces of the collieries increase as the respirable dust levels and quartz contents increase in general. This finding indicates that the TLV (5mg/m3) of Turkey should be re-evaluated and additional safety precautions should be taken in the workplaces where high quartz contents of respirable dust exist.

Coal Mine Dust Lung Disease. New Lessons from an Old Exposure

Coal mining remains a sizable industry, with millions of working and retired coal miners worldwide. This article provides an update on recent advances in the understanding of respiratory health issues in coal miners and focuses on the spectrum of disease caused by inhalation of coal mine dust, termed coal mine dust lung disease. In addition to the historical interstitial lung diseases (coal worker's pneumoconiosis, silicosis, and mixed dust pneumoconiosis), coal miners are at risk for dust-related diffuse fibrosis and chronic airway diseases, including emphysema and chronic bronchitis. Recent recognition of rapidly progressive pneumoconiosis in younger miners, mainly in the eastern United States, has increased the sense of urgency and the need for vigilance in medical research, clinical diagnosis, and exposure prevention. Given the risk for disease progression even after exposure removal, along with few medical treatment options, there is an important role for chest physicians in the recognition and management of lung disease associated with work in coal mining.

Evaluation of the oblique fissure on lateral chest radiographs in coal workers pneumoconiosis

The oblique fissure separates the upper lobe from the lower lobe in the left lung and the upper lobe from the lower and middle lobes in the right lung. The aim of the present study was to compare the projection of the oblique fissure observed on lateral chest radiographs of retired coal mine workers who had coal worker's pneumoconiosis (CWP) with that of healthy men. The study included 120 men divided into three groups: retired coal miner patients diagnosed with CWP (group 1), men ≥38 years of age with no CWP (group 2, first control group), and men ≤37 years of age with no CWP (group 3, second control group). The projection of the oblique fissure observed on lateral chest radiographs (left side) were evaluated using geometric morphometrics. Geometric morphometric analysis of each sample was performed using 11 pre-specified landmarks designated on X-ray images, using tpsDig2 software. A text file containing the landmark coordinates of the 120 samples was created, and the data in the text file was statistically analyzed using Morpheus software. The projection of the oblique fissure differed significantly between the CWP patients and the control groups (p<0.05). We suggest that the difference in the projection of the oblique fissure between men with and without CWP was attributable to a protrusion in the fissure caused by nodules that developed in the lungs of coal miners after years of dust inhalation (Tab. 4, Fig. 4, Ref. 30).

Annexin A5 gene polymorphism (-1C/T) and the susceptibility to pneumoconiosis in coal works

To explore the role of -1C/T single nucleotide polymorphism within Annexin A5 gene in the genetic susceptibility to coal worker's pneumoconiosis (CWP). Four hundred and seventy CWP Han chinese patients and 428 Han chinese controls were enclosed in present case-control study. All subjects were exposed to coal dusts. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to detect the -1C/T SNP in Annexin A5 gene for all subjects. The relationship between the -1C/T SNP in Annexin A5 gene and CWP was analyzed. CT/TT genotype in -1C/T SNP was associated with a significantly decreased risk of CWP, as compared with the CC genotype among subgroups exposed to coal dusts for ≥ 27 years (adjusted OR = 0.65, 95%CI: 0.44 - 0.98, P = 0.039) and patients with CWP at stage II (adjusted OR = 0.55, 95%CI: 0.34 - 0.90, P = 0.028). The results of present study suggest that the Annexin A5 -1C/T polymorphism may be involved in the development of CWP in Han Chinese coal miners.

The Influence of Dust Standards on the Prevalence and Severity of Coal Worker's Pneumoconiosis at Autopsy in the United States of America

Coal worker's pneumoconiosis is a major occupational lung disease in the United States. The disease is primarily controlled through reducing dust exposure in coal mines using technological improvements and through the establishment of dust standards by regulatory means. To determine if dust standards established in the US Federal Coal Mine Health and Safety Act of 1969 have reduced the prevalence and severity of coal worker's pneumoconiosis. The study population included materials from 6103 deceased coal miners submitted to the National Coal Workers' Autopsy Study from 1971 through 1996. Type and severity of coal worker's pneumoconiosis were classified using standardized diagnostic criteria. Among miners who worked exclusively prior to the 1969 dust standard, 82.6% had coal macules, 46.3% coal nodules, 28.2% silicotic nodules, and 10.3% progressive massive fibrosis. Lower prevalences were noted among miners exposed exclusively to post-1970 dust levels: 58.8% had coal macules, 15.0% coal nodules, 8.0% silicotic nodules, and 1.2% progressive massive fibrosis. The differences in prevalence were highly significant (P < .001) for all types of pneumoconiosis, including progressive massive fibrosis, after adjustment for age, years of mining, and smoking status. The study confirms a beneficial impact of the first 25 years of the dust standard established by the 1969 act on the prevalence and severity of coal worker's pneumoconiosis in US coal miners. However, pneumoconiosis continues to occur among miners who have worked entirely within the contemporary standard, suggesting a need for further reductions in exposure to respirable coal mine dust.

Pyrite-driven reactive oxygen species formation in simulated lung fluid: implications for coal workers’ pneumoconiosis

The origin of coal worker's pneumoconiosis (CWP) has been long debated. A recent epidemiological study shows a correlation between what is essentially the concentration of pyrite within coal and the prevalence of CWP in miners. Hydrogen peroxide and hydroxyl radical, both reactive oxygen species (ROS), form as byproducts of pyrite oxidative dissolution in air-saturated water. Motivated by the possible importance of ROS in the pathogenesis of CWP, we conducted an experimental study to evaluate if ROS form as byproducts in the oxidative dissolution of pyrite in simulated lung fluid (SLF) under biologically applicable conditions and to determine the persistence of pyrite in SLF. While the rate of pyrite oxidative dissolution in SLF is suppressed by 51% when compared to that in air-saturated water, the initial amount of hydrogen peroxide formed as a byproduct in SLF is nearly doubled. Hydroxyl radical is also formed in the experiments with SLF, but at lower concentrations than in the experiments with water. The formation of these ROS indicates that the reaction mechanism for pyrite oxidative dissolution in SLF is no different from that in water. The elevated hydrogen peroxide concentration in SLF suggests that the decomposition, via the Fenton mechanism to hydroxyl radical or with Fe(III) to form water and molecular oxygen, is initially inhibited by the presence of SLF components. On the basis of the oxidative dissolution rate of pyrite measured in this paper, it is calculated that a respirable two micron pyrite particle will take over 3years to dissolve completely.

Coal worker's pneumoconiosis complicated with lung cancer patients with respiratory tract of drug resistance of Pseudomonas aeruginosa

目的 探讨煤工尘肺肺癌并发下呼吸道感染患者耐亚胺培南铜绿假单胞菌(IRPA)耐药性.方法 对分离于80例尘肺并发肺癌下呼吸道感染患者的108株IRPA,用Kerby-Bauer法进行耐药性分析.结果 煤工尘肺肺癌并发下呼吸道感染80例患者的痰液标本中分离出106株铜绿假单胞菌,其中,IRPA 32株,检出率为30.2%.亚胺培南敏感铜绿假单胞菌(ISPA)74株,检出率为69.8%.IRPA对阿米卡星和环丙沙星的敏感率分别为59.5%和56.8%.结论 IRPA对抗生素的耐药性强,临床医师在治疗中应注意合理使用抗生素。

Analysis of developing feature of pneumoconiosis

To get the message about the developing feature of pneumoconiosis by analyzing the data from 353 cases of pneumoconiosis diagnosed in our hospital recent 6 years. To analyze the onset age, onset service years and incubation period of 353 cases of pneumoconiosis, especially in silicosis, coal worker's pneumoconiosis and potter's pneumoconiosis. 353 patients referred to 10 species of pneumoconiosis, the silicosis, coal worker's pneumoconiosis and potter's pneumoconiosis were accounted for 28.90%, 43.34% and 15.01% of total pneumoconiosis respectively. Diagnosed patients who began to exposed to dust during 1950's to 1980's accounted for 84.99% of all the diagnosed patients. The onset age, onset service years and incubation period of silicosis, coal worker's pneumoconiosis and potters pneumoconiosis all showed a shorten trend compared each other every decade, especially after 1980's, but excluded potter's pneumoconiosis because of that the ceramics industry switched to other products in Beijing. There was a positive correlation relationship between average onset age and incubation period in three main species of pneumoconiosis mentioned above, but no significant difference could be seen in average promotion years. Additionally, comparing with other type of work, jade machining workers showed such a characteristic as younger onset and short incubation period. The development situation of silicosis, coal worker's pneumoconiosis is still no so optimistic, and the strict surveillance and administration especially to the township enterprises with poor production conditions should get further strengthen.

Clinical study on simvastatin treatment of pulmonary hypertension in patients with coal worker's pneumoconiosis

To observe simvastatin treatment of pulmonary hypertension in patients with coal workers pneumoconiosis (CWP). 96 CWP patients with pulmonary hypertension were randomly divided into treatment and control groups. The control group was treated with 2.5 mg warfarin, once a day for four months; the treatment group was treated with 20 mg simvastatin, taken in evening, for 4 months. 6 min walking distance (6MWD) test and inspection pulmonary artery pressure were measured by echocardiography before and after treatment. In the treatment group, the 6MWD were (258 ± 26) m after treatment and (225 ± 19) m before treatment, respectively. Compared with control group, pulmonary artery pressure was (41 ± 9) mm Hg in the treatment group before treatment, (36 ± 3) mm Hg in the treatment group after treatment, and (39 ± 5) mm Hg in control group, respectively, the difference was statistically significant (P < 0.05). Simvastatin can improve pulmonary hypertension in coal workers pneumoconiosis, and shows a definite curative effect.

Clinical Year-in-Review of Occupational Lung Disease

Occupational lung disease (OLD) is a group of lung diseases caused and/or aggravated by organic and inorganic inhaled dust, fumes, and mist. OLD can develop under various occupational situations. Therefore, occupational history should be considered when evaluating respiratory symptoms. Once OLD is developed, it may not be treated and may even progress after exposure to the causative agents has stopped. The best ways to treat OLD are prevention and early detection by controlling the working environment and conducting regular surveillance of workers. Common OLDs in Korea are coal worker's pneumoconiosis, asbestos-related diseases, and occupational asthma. Recent aspects of these common OLDs in Korea will be described based on recently published studies.

SMAD4 gene polymorphisms and genetic susceptibility of coal work's pneumoconiosis

to explore whether 6 tagging single nucleotide polymorphisms (SNPs) within SMAD4 gene were involved in the genetic susceptibility of coal worker's pneumoconiosis (CWP) by case-control study. this study consisted of 438 CWP patients and 448 controls. All study subjects were Han Chinese, underground coal miners and recruited from coal mines of Xuzhou Mining Business Group Co Ltd. The 5 ml venous blood sample was obtained from all studied subjects and extracted genome DNA from the isolated leucocytes. Six SNPs were selected from the HapMap and detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). the single SNP analyses showed that the genotype frequencies of SMAD4 (rs10502913) was significantly different from those in controls (P < 0.05). Multivariate logistic regression analyses revealed that SMAD4 (rs10502913) AA genotype was associated with increased risk of CWP (adjusted OR = 1.63, 95%CI = 1.00 - 2.69, P = 0.05) and this was evident among subgroups of those smoker (adjusted OR = 2.28, 95%CI = 1.09 ∼ 4.80, P < 0.05) and cases with stage I (adjusted OR = 2.42, 95%CI = 1.41 ∼ 4.14, P < 0.01). The SMAD4 (rs9304407) GG genotype was associated with an decreased risk of CWP (adjusted OR = 0.65, 95%CI = 0.43 ∼ 0.98, P < 0.05) and the further stratification analysis showed that the risk of CWP was decreased in nonsmoking groups. our results suggest that individuals with the SMAD4 (rs10502913) AA genotype was associated with an increased risk of CWP. However, carriers of SMAD4 (rs9304407) GG genotype have a protective effect on the developing CWP.