American Journal of Respiratory and Critical Care Medicine. 2008 Jun 12. [Epub ahead of print] [Link]
Mapping the Risk of Mesothelioma due to Neighborhood Asbestos Exposure.
Kurumatani N, Kumagai S.
Department of Community Health and Epidemiology, Nara Medical University, Kashihara, Nara, Japan.
Rationale: Little is known about neighborhood exposure to asbestos and mesothelioma risk among residents around an industrial source of asbestos.
Objectives: To investigate the magnitude of the risk among residents by asbestos exposure levels and to determine the range of the area affected by asbestos.
Methods: We calculated standardized mortality ratios of mesothelioma from 1995 to 2006 among the estimated population at risk that lived around a former large asbestos cement pipe plant in Amagasaki City, Japan between 1957 and 1975, the time when the plant had used crocidolite and chrysotile. Distance between the plant and homes and asbestos relative concentrations obtained by diffusion equations involving meteorological conditions were used as asbestos exposure levels among residents.
Main results: We identified 73 mesothelioma deaths in 35 men and 38 women as having no occupational exposure to asbestos. Among persons who had lived within a 300-meter radius from the plant, the standardized
mortality ratio of mesothelioma was 13.9 (95% C.I.: 5.6- 28.7) in men and 41.1 (95% C.I.: 15.2- 90.1) in women. When the study area was divided into five regions by relative asbestos concentration, standardized mortality ratios of mesothelioma declined, for both sexes, in a linear dose-dependent manner with the concentration. The regions with a significantly elevated standardized mortality ratio reached 2,200 meters from the plant in the same direction toward which the wind predominantly blew.
Conclusions: Neighborhood exposure to asbestos can pose a serious risk to residents across a wide area.
Keywords: asbestos relative concentration, crocidolite, environmental exposure, pleural mesothelioma