In Californië is bij onderzoek geconstateerd dat naarmate mensen dichter bij een natuurlijke asbestvindplaats wonen het risico op longvlieskanker (pleuraal mesothelioom) groter is. Voor buikvlieskanker (peritoneaal mesothelioom) geldt dit niet. Buikvlieskanker wordt normaal gesproken veroorzaakt door hogere blootstellingsniveaus dan longvlieskanker. De resultaten lijken erop te wijzen dat ook mensen die relatief ver van een asbestvindplaats wonen een verhoogd risico op longvlieskanker hebben. Goldberg en Luce menen dat deze resultaten de stelling ondersteunen dat ook lage niveaus van asbestblootstelling kankerverwekkend kunnen zijn. Bron: 1. Pan XL, Day HW, Wang W, Beckett LA, Schenker MB (2005). Residential proximity to naturally occurring asbestos and mesothelioma risk in California. Am J Respir Crit Care Med. 2005 Oct 15.172(8):1019-25 , 2. Goldberg M, Luce D. (2005). Can exposure to very low levels of asbestos induce pleural mesothelioma? Am J Respir Crit Care Med. 2005 Oct 15.172(8):939-40.

Pan XL, Day HW, Wang W, Beckett LA, Schenker MB (2005). Residential proximity to naturally occurring asbestos and mesothelioma risk in California. Am J Respir Crit Care Med. 2005 Oct 15.172(8):1019-25

Abstract

Rationale: Little is known about environmental exposure to low levels of naturally occurring asbestos (NOA) and malignant mesothelioma (MM) risk.

Objectives: To conduct a cancer registry-based case control study of residential proximity to NOA with MM in California.

Methods: Incident MM cases (n = 2,908) aged 35 yr or more, diagnosed between 1988 and 1997, were selected from the California Cancer Registry and frequency matched to control subjects with pancreatic cancer (n = 2,908) by 5-yr age group and sex. Control subjects were selected by stratified random sampling from 28,123 incident pancreatic cancers in the same time period. We located 93.7% of subjects at the house or street level at initial diagnosis. Individual occupational exposure to asbestos was derived from the longest held occupation, available for 74% of MM cases and 63% of pancreatic cancers. Occupational exposure to asbestos was determined by a priori classification and confirmed by association with mesothelioma.

Main Results: The adjusted odds ratios and 95% confidence interval for low, medium, and high probabilities of occupational exposures to asbestos were 1.71 (1.32-2.21), 2.51 (1.91-3.30), and 14.94 (8.37-26.67), respectively. Logistic regression analysis from a subset of 1,133 mesothelioma cases and 890 control subjects with pancreatic cancer showed that the odds of mesothelioma decreased approximately 6.3% for every 10 km farther from the nearest asbestos source, an odds ratio of 0.937 (95% confidence interval = 0.895-0.982), adjusted for age, sex, and occupational exposure to asbestos.

Conclusions: These data support the hypothesis that residential proximity to NOA is significantly associated with increased risk of MM in California.