Mapping the risk of mesothelioma due to neighborhood asbestos exposure.
BACKGROUND
Little is known about neighborhood exposure to asbestos and mesothelioma risk among residents around an industrial source of asbestos.


OBJECTIVE
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. The distance between the plant and homes and relative asbestos concentrations obtained by diffusion equations involving meteorological conditions were used to determine asbestos exposure levels among residents.


RESULTS
We identified 73 mesothelioma deaths of 35 men and 38 women who had no occupational exposure to asbestos. Among persons who had lived within a 300-m radius of the plant, the standardized mortality ratio of mesothelioma was 13.9 (95% confidence interval, 5.6-28.7) for men and 41.1 (95% confidence interval, 15.2-90.1) for 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 concentration. The regions with a significantly elevated standardized mortality ratio reached 2,200 m from the plant in the same direction in which the wind predominantly blew.


CONCLUSIONS
Neighborhood exposure to asbestos can pose a serious risk to residents across a wide area.
Kurumatani
Norio
N
Department of Community Health and Epidemiology, Nara Medical University School of Medicine, 840 Shijyocho, Kashihara, Nara 634-8521, Japan. knorio@naramed-u.ac.jp
Kumagai
Shinji
S
D000368:Aged; D000393:Air Pollutants; D017638:Asbestos, Crocidolite; D001195:Asbestosis / Q000453:epidemiology*; D016000:Cluster Analysis; D004305:Dose-Response Relationship, Drug; D004781:Environmental Exposure; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008654:Mesothelioma / Q000453:epidemiology* / Q000401:mortality; D008875:Middle Aged; D010997:Pleural Neoplasms / Q000453:epidemiology* / Q000401:mortality; D018570:Risk Assessment
D000393:Air Pollutants; D017638:Asbestos, Crocidolite