Polycyclic aromatic hydrocarbon exposure in oesophageal tissue and risk of oesophageal squamous cell carcinoma in north-eastern Iran

Abedi-Ardekani, Behnoush; Kamangar, Farin; Hewitt, Stephen M.; Hainaut, Pierre; Sotoudeh, Masoud; Abnet, Christian C.; Taylor, Philip R.; Boffetta, Paolo; Malekzadeh, Reza; Dawsey, Sanford M.

doi:10.1136/gut.2010.210609

Cited by 74 publications

(76 citation statements)

References 32 publications

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“…In the atmosphere, the fraction of certain PAHs in the gaseous phase can reach up to 90%. 19 In addition, the gas-phase reactions of PAHs with OH and NO 3 radicals are generally faster compared to the heterogeneous reactions of particulate PAHs with N 2 O 5 or HNO 3 . 20 Thus, the gas-phase formation has been recognized as a significant source of nitro-PAHs in the atmosphere.…”

Section: Introductionmentioning

confidence: 99%

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Role of Water Molecule in the Gas-Phase Formation Process of Nitrated Polycyclic Aromatic Hydrocarbons in the Atmosphere: A Computational Study

Zhang

Gao

et al. 2014

Environ. Sci. Technol.

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Nitro-PAHs are globally worrisome air pollutants because their high direct-acting mutagenicity and carcinogenicity. A mechanistic understanding of their formation is of crucial importance for successful prevention of their atmospheric pollution. Here, the formation of nitroPAHs arising from the OH-initiated and NO 3 -initiated atmospheric reactions of PAHs was investigated by using quantum chemical calculations. It is widely assumed that OH or NO 3 radicals attack on the C atoms of the aromatic rings in the PAH molecule, followed by the addition of NO 2 to the OH−PAH or NO 3 −PAH adducts at the ortho position and the loss of water or nitric acid to form nitro-PAHs. However, calculations show that the direct loss of water from the OH−NO 2 −PAH adducts via the unimolecular decomposition is energetically unfavorable. This study reveals for the first time that water molecule plays an important catalytic effect on the loss of water from the OH−NO 2 −PAH adducts and promotes the formation of nitro-PAHs. In addition, the introduction of water unwraps new formation pathway through the addition of NO 2 to the OH−PAH or NO 3 −PAH adduct at the para position. The individual and overall rate constants for the addition reactions of PAHs with OH and NO 3 radicals were deduced by using the Rice−Ramsperger−Kassel−Marcus (RRKM) theory.

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Section: Introductionmentioning

confidence: 99%

“…Nitro-PAHs can be formed in the atmosphere via homogeneous gas-phase reactions of PAHs with OH or NO 3 radicals in the presence of NO 2 and heterogeneous reactions of particulate PAHs with N 2 O 5 or HNO 3 . In the atmosphere, the fraction of certain PAHs in the gaseous phase can reach up to 90%.…”

Section: Introductionmentioning

confidence: 99%

Role of Water Molecule in the Gas-Phase Formation Process of Nitrated Polycyclic Aromatic Hydrocarbons in the Atmosphere: A Computational Study

Zhang

Gao

et al. 2014

Environ. Sci. Technol.

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“…The regions with high rate of mortality from esophageal cancer are situated in Central Asia (Asian Belt), France, Italy, Brazil, Eastern and Southern Africa. The noticeable point is that in these countries we witness the presence of focal points with very high risks of morbidity along with less morbid zones [7][8][9]. The studies show that during recent decades esophageal cancer has decreased in the Asian Belt Zone and the occurrence of this cancer has reduced to about 50% in china.…”

Section: Introductionmentioning

confidence: 99%

“…In contrast, the sudden rise in the occurrence of the disease was seen among the black race in USA. Such time developments are totally considered as the evidences for change in the related exposures to the given disease [6,[8][9][10]. The maximum reported rate of morbidity from esophageal cancer in the world belongs to a report from the Cancer Center in the Caspian Sea.…”

Section: Introductionmentioning

confidence: 99%

Trend of the Esophageal Cancer Incidence in IRAN

Jafari

Moradi

Khodadost

et al. 2015

ijtmgh

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Introduction: Cancer is one of the main causes for mortality and morbidity in the world. Identifying epidemiology and the trend of esophageal cancer may be highly effective in related planning. The present study has been carried out with the aim of exploring the morbidity and trend of esophageal cancer in Iran. Methods:The present study is a type of repeated analysis of the existing data. The population of this study consisted of the cancer registry data during the years (2003)(2004)(2005)(2006)(2007)(2008)(2009)) in Iran. The direct incidence rate was standard according to the World Health Organization (WHO) population. The incidence trend of this disease in this country was drawn by the means of the STATA software and the significance of the morbidity trend diagram was also derived via WINPEPI software. Results:The results indicated the increasing trend of esophageal cancer up to 2008 while this trend has been dropping during the years 2008-9. The 31914 cases of esophageal cancer which have been recorded throughout the country out of which this rate has been increased from 2759 cases in 2003 to 6210 cases in 2009 so this rate signifies 2 times in morbidity and the recording of cases. During this 7-year career, the maximum incidence rate was related to the Ardabil province with 19.03 per 100'000 cases in 2009 while the minimum incidence rate was related to Chahar Mahal and Bakhtiari and also Booshehr provinces with 0.48 and 0.42% per 1000 cases in 2003, respectively. Conclusion: The incidence rate of esophageal cancer in Iran is increasing, particularly in the northern and northwestern regions of the country. It is recommended to employ screening programs and premature diagnosis in the regions and among high risk populations.

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“…For a case-control study, the sample quantiles from controls are often used. For example, [1] conducted a case-control study of 91 cases of esophageal squamous cell carcinoma and 103 controls and categorized staining intensity, a continuous measure, based on quintiles in the controls. Yet sample size calculations typically assume that the population quantiles are known.…”

Section: Introductionmentioning

confidence: 99%

Power of the Cochran-Armitage trend test when exposure scores are based on empirical quantiles of exposure

Gail

2012

Statistics and Its Interface

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Epidemiologists often categorize exposures based on quantiles of exposure and use the Cochran-Armitage trend test based on such categories to detect associations between disease and exposure. Power calculations typically assume that the population quantiles are known, but in practice quantiles are often estimated from the sample data. We evaluated the power of the Cochran-Armitage trend test for cohort designs and for case-control designs in which sample quantiles of exposure in the cohort or in controls from a case-control study, respectively, are used to define the cutpoints that separate exposure score categories. We give the asymptotic formulas for size and power for the CochranArmitage test based on empirical quantiles separately for cohort and case-control designs, together with efficient simulation methods to estimate size and power. Numerical results indicate that estimation of sample quantiles has only a slight effect on power for cohort studies with at least four categories or with more than 280 subjects. However, estimating quantiles can reduce power appreciably in smaller studies with fewer than four exposure categories. For casecontrol studies of rare diseases, the power loss is limited with more than 120 cases plus controls if the odds ratio comparing the highest exposure category to the lowest category is greater than 0.5. However, if that odd ratio is smaller than 0.5, only samples with more than 360 cases plus controls can guarantee a small loss of power, and increasing the number of exposure categories does not eliminate the loss of power.

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Polycyclic aromatic hydrocarbon exposure in oesophageal tissue and risk of oesophageal squamous cell carcinoma in north-eastern Iran

Cited by 74 publications

References 32 publications

Role of Water Molecule in the Gas-Phase Formation Process of Nitrated Polycyclic Aromatic Hydrocarbons in the Atmosphere: A Computational Study

Role of Water Molecule in the Gas-Phase Formation Process of Nitrated Polycyclic Aromatic Hydrocarbons in the Atmosphere: A Computational Study

Trend of the Esophageal Cancer Incidence in IRAN

Power of the Cochran-Armitage trend test when exposure scores are based on empirical quantiles of exposure

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