Once considered a taboo topic or stigma, cancer is the number one public health enemy in the world. Once a product of an almost untouchable industry, tobacco is indisputably recognized as a major cause of cancer and a target for anticancer efforts. With the emergence of new economic powers in the world, especially in highly populated countries such as China, air pollution has rapidly emerged as a smoking gun for cancer and has become a hot topic for public health debate because of the complex political, economic, scientific, and technologic issues surrounding the air pollution problem. This editorial and the referred articles published in this special issue of the Chinese Journal of Cancer discuss these fundamental questions. Does air pollution cause a wide spectrum of cancers? Should air pollution be considered a necessary evil accompanying economic transformation in developing countries? Is an explosion of cancer incidence coming to China and how soon will it arrive? What must be done to prevent this possible human catastrophe? Finally, the approaches for air pollution control are also discussed.
Air Pollution ; adverse effects ; Carcinogens, Environmental ; toxicity ; China ; Humans ; Neoplasms ; etiology ; Risk Factors ; Smoking ; adverse effects

OBJECTIVETo determine if there are excessive risks of malignant tumors or not among workers exposed to asbestos by applying a meta-analysis technique.

METHODSAll data meeting the criteria of cohort studies on cancer mortality of digestive system among workers exposed to asbestos would be incorporated into the meta-analysis. The pooled standardized mortality ratios (SMR) and their corresponding 95% confidence intervals (CIs) for main cancer sites of digestive system were calculated by using two approaches of un-weighted ratio and random effects model. The heterogeneity and its sources of the results were examined with a Q-statistic and Z-score test.

RESULTS69 asbestos-exposed cohorts were summarized. The significantly elevated meta-SMR for all deaths (1.16), all cancers (1.42), cancer of digestive system (1.15) and cancer of stomach (1.20) among workers exposed to chrysotile alone or mixed asbestos were observed (P < 0.01). The stomach cancer SMR was significantly increased in the asbestos cement workers, the screening mine workers and the insulators, (1.27, 1.21 and 2.13 respectively) (P < 0.05). meta-SMR for cancers at other sites of digestive system including esophagus, colon, rectum and liver were not significant.

CONCLUSIONThere are likely excessive risks of cancer of stomach among workers exposed to asbestos. However, there is likely no convincing indication of an etiological association between asbestos exposure and cancers at other sites of digestive system.

Asbestos ; adverse effects ; Carcinogens, Environmental ; adverse effects ; Cohort Studies ; Digestive System Neoplasms ; chemically induced ; mortality ; Humans ; Occupational Exposure ; adverse effects

Epidermal growth factor receptor (EGFR) is a classic protein tyrosine kinase receptor, which plays an important role in cell proliferation, survival, adhesion, differentiation and apoptosis. Abnormality of EGFR and its signaling are closely associated with tumor initiation and development. Many environmental physical and chemical agents can interfere with EGFR and its signal transduction pathways via affecting its phosphorylation, conformation and function, or distribution on cell membrane, finally influencing gene expression and cell fate. This review focuses on the recent progress of above aspects for further understanding of epigenetic mechanisms of cellular stress and carcinogenesis related with environmental agents.
Carcinogens ; Environmental Exposure ; adverse effects ; Environmental Pollutants ; adverse effects ; Humans ; Phosphorylation ; Receptor, Epidermal Growth Factor ; drug effects ; metabolism ; Signal Transduction ; drug effects

Recently, the International Agency for Research on Cancer (IARC) has classified outdoor air pollution and the particulate matter component of outdoor air pollution as class I carcinogen. Air pollution is consistently associated with lung cancer in epidemiologic and experimental studies. The IARC assessment is specifically designed as hazard identification, and it does not quantify the magnitude of the cancer risk. This article addresses the magnitude of the lung cancer risk in the population due to ambient air pollution exposure.
Air Pollutants ; toxicity ; Air Pollution ; adverse effects ; Carcinogens, Environmental ; toxicity ; Humans ; Lung Neoplasms ; etiology ; Particulate Matter ; toxicity ; Risk Factors

The International Agency for Research on Cancer (IARC) has classified outdoor air pollution and the particulate matter (PM) in outdoor air pollution as carcinogenic to humans, as based on sufficient evidence of carcinogenicity in humans and experimental animals and strong support by mechanistic studies. The data with important contributions to the evaluation are reviewed, highlighting the data with particular relevance to China, and implications of the evaluation with respect to China are discussed. The air pollution levels in Chinese cities are among the highest observed in the world today and frequently exceed health-based national and international guidelines. Data from high-quality epidemiologic studies in Asia, Europe, and North America consistently show positive associations between lung cancer and PM exposure and other indicators of air pollution, which persist after adjustment for important lung cancer risk factors, such as tobacco smoking. Epidemiologic data from China are limited but nevertheless indicate an increased risk of lung cancer associated with several air pollutants. Excess cancer risk is also observed in experimental animals exposed to polluted outdoor air or extracted PM. The exposure of several species to outdoor air pollution is associated with markers of genetic damage that have been linked to increased cancer risk in humans. Numerous studies from China, especially genetic biomarker studies in exposed populations, support that the polluted air in China is genotoxic and carcinogenic to humans. The evaluation by IARC indicates both the need for further research into the cancer risks associated with exposure to air pollution in China and the urgent need to act to reduce exposure to the population.
Air Pollutants ; toxicity ; Air Pollution ; adverse effects ; Animals ; Asia ; Carcinogens, Environmental ; toxicity ; China ; Environmental Exposure ; Humans ; International Agencies ; Lung Neoplasms ; etiology ; Neoplasms ; etiology ; Particulate Matter ; toxicity ; Risk Factors

OBJECTIVETo study the relationship between low benzene exposure doses with workers' peripheral blood parameters of different similar exposure groups (SEG).

METHODSThe workers were from a shoe factory and divided into different SEG, according to the observation method and sampling method. Exposure levels, blood samples and job histories were collected. The relationship between benzene level and blood routine were analyzed using multiple regression method.

RESULTSFive SEGs were defined. No significant differences were found among different SEG in length of service, smoking, drinking, blood routine and symptoms except for ages. Significant negative correlation (r = -0.36, P < 0.05) between benzene exposure levels and white blood cell counts were found by multiple regression analysis. Similar negative correlation was also found between length of benzene exposure and red blood cell counts (r = -0.29, P < 0.05). No significantly statistical relationships were found between benzene exposure and red blood cell counts or platelet count.

CONCLUSIONSEGs method is sensitive for determining the relationship between benzene exposure levels and white blood cell counts. Further study is needed by increasing the number of workers to study the relationship between low benzene exposure and peripheral blood parameters.

Benzene ; adverse effects ; analysis ; Blood Cell Count ; Carcinogens ; adverse effects ; analysis ; China ; Dose-Response Relationship, Drug ; Environmental Monitoring ; instrumentation ; methods ; Humans ; Industry ; No-Observed-Adverse-Effect Level ; Occupational Exposure ; adverse effects ; analysis

Air pollution in China comes from multiple sources, including coal consumption, construction and industrial dust, and vehicle exhaust. Coal consumption in particular directly determines the emissions of three major air pollutants: dust, sulfur dioxide (SO(2)), and nitrogen oxide (NOx). The rapidly increasing number of civilian vehicles is expected to bring NOx emission to a very high level. Contrary to expectations, however, existing data show that the concentrations of major pollutants [particulate matter-10 (PM10), SO(2), and nitrogen dioxide (NO(2))] in several large Chinese cities have declined during the past decades, though they still exceed the national standards of ambient air quality. Archived data from China does not fully support that the concentrations of pollutants directly depend on local emissions, but this is likely due to inaccurate measurement of pollutants. Analyses on the cancer registry data show that cancer burden related to air pollution is on the rise in China and will likely increase further, but there is a lack of data to accurately predict the cancer burden. Past experience from other countries has sounded alarm of the link between air pollution and cancer. The quantitative association requires dedicated research as well as establishment of needed monitoring infrastructures and cancer registries. The air pollution-cancer link is a serious public health issue that needs urgent investigation.
Air Pollutants ; toxicity ; Air Pollution ; adverse effects ; Carcinogens, Environmental ; toxicity ; China ; Coal ; Humans ; Neoplasms ; etiology ; Nitrogen Dioxide ; toxicity ; Particulate Matter ; toxicity ; Sulfur Dioxide ; toxicity ; Vehicle Emissions ; toxicity

OBJECTIVETo study the methylation of O-6-methylguanine-DNA methyltransferase (MGMT) and p16 gene in the sputum cells of radon-exposed population. To provide the experimental base for finding the molecular biomarker of the high risk population of the radon-induced lung cancer.

METHODS91 radon-exposed workers were divided into 4 groups, high dosage group (> 120 WLM), middle dosage group (between 60 and 120 WLM), low dosage group (between 30 and 60 WLB) and lower dosage group (between 2 and 30 WLM) according to the accumulated exposure dosage of the radon daughters. The abnormal methylation of p16 and MGMT gene in the sputum cells of the population in the four groups was detected with the methylation specific PCR (MSP).

RESULTSThere was significantly upward trend for the p16 gene methylation rate (0.00%-20.00%), the MGMT gene methylation rate (0.00%-28.00%) and the total methylation rate (0.00%-40.00%) with the increase of the accumulated exposure dosage of the radon daughters (P < 0.01).

CONCLUSIONThe methylation of p16 and MGMT gene is related to the accumulate exposure dosage of the radon daughters.

Carcinogens, Environmental ; adverse effects ; Cyclin-Dependent Kinase Inhibitor p16 ; genetics ; metabolism ; DNA Methylation ; Dose-Response Relationship, Radiation ; Humans ; Male ; O(6)-Methylguanine-DNA Methyltransferase ; genetics ; metabolism ; Occupational Exposure ; Radon ; adverse effects ; Radon Daughters ; adverse effects ; Sputum ; metabolism

No abstract available.
Antineoplastic Combined Chemotherapy Protocols/therapeutic use ; Carcinogens, Environmental/adverse effects ; Combined Modality Therapy ; Helicobacter Infections/epidemiology/microbiology ; Helicobacter pylori ; Human ; Incidence ; Korea/ethnology ; *Precancerous Conditions ; Prognosis ; *Stomach Neoplasms/epidemiology/etiology/therapy ; *Transients and Migrants ; United States/epidemiology