Sivas province of Turkey, ophiolites, and mesothelioma

http://www.ncbi.nlm.nih.gov/pubmed/22814683

Chest. 2012 Jul 17. doi: 10.1378/chest.11-2727. [Epub ahead of print]

HIGH RISK OF MALIGNANT MESOTHELIOMA AND PLEURAL PLAQUES IN SUBJECTS BORN CLOSE TO OPHIOLITES.

Bayram1 M, Dongel2 I, Bakan3 ND, Yalçın4 H, Cevit5 R, Dumortier6 P, Nemery7 B.

Abstract

ABSTRACT

BACKGROUND:

Ophiolites- a special sequence of geologic rock units - are known sources of naturally occurring asbestos. The aim of the study was to test whether the occurrence of malignant mesothelioma (MM) or pleural plaques (PP) in the province of Sivas, Turkey, is determined by the proximity of the patient's birthplace with respect to ophiolites and, if so, to establish the magnitude of the risk.

METHODS:

The birthplaces of patients with MM or PP (cases) and patients with prostate or breast cancer (controls) diagnosed between 2000 and 2010 and identified through a mandatory cancer registry or from hospital records (PP), were located on a geological map and the nearest distance to ophiolites was measured. The relation of MM or PP with distance to ophiolites was analyzed by logistic regression. Samples of soil and house plaster were determined by X-ray diffraction.

RESULTS:

Patients with MM (n=100) or PP (n=133) were born significantly nearer to ophiolites [median distance 4.5 km for men; 0 km for women] than patients with prostate cancer (n=161) or breast cancer (n=139) [median distance 20 km for both]. Odd ratios were 1.6 (males) (p<0.001) and 2.0 females) (p<0.001) for every 5 km decrease in the distance of birthplace to ophiolites for MM compared to prostate and breast cancer, respectively.

CONCLUSION:

In this area without substantial industrial asbestos use, there is an association between the occurrence of mesothelioma (and of pleural plaques) and the proximity of the subjects' birthplace to ophiolites.