Non-occupational exposure to asbestos and malignant mesothelioma in the Italian National Registry of Mesotheliomas.
BACKGROUND
Malignant mesotheliomas are strictly related to asbestos, but in a proportion of cases no exposure can be recalled. Published estimates of this proportion have important variations. Historical and geographical differences in the fraction of cancer due to any given exposure are to be expected, but incomplete identification of non-occupational exposures may have played a role.


METHODS
To assess the role of non-occupational exposures in causing malignant mesotheliomas in Italy, the exposures of cases registered by the national mesothelioma registry (ReNaM) were examined. ReNaM started in 1993 in five regions and currently covers 98% of the Italian population. Information on occupational and non-occupational exposures of cases is collected whenever possible.


RESULTS
From 1993 to 2001 ReNaM registered 5173 malignant mesothelioma cases, and exposures were assessed in 3552 of them. 144 and 150 cases with exposures limited to environmental (living in the neighbourhood of an industrial or natural source of asbestos) or familial (living with a person occupationally exposed to asbestos) circumstances, respectively, were identified, accounting for 8.3% of all cases.


CONCLUSIONS
Geographical variations in the proportion of cases due to non-occupational exposures may be explained by the past distribution of asbestos-using industries.
Unit of Cancer Epidemiology, Via Santena 7, 10126 Torino (TO), Italy. dario.mirabelli@cpo.it
Dario
D
Mirabelli
Domenica
D
Cavone
Enzo
E
Merler
Valerio
V
Gennaro
Antonio
A
Romanelli
Carolina
C
Mensi
Elisabetta
E
Chellini
Carmela
C
Nicita
Alessandro
A
Marinaccio
Corrado
C
Magnani
Marina
M
Musti
D000328:Adult; D000368:Aged; D001194:Asbestos / Q000633:toxicity*; D004781:Environmental Exposure / Q000009:adverse effects* / Q000706:statistics & numerical data; D005192:Family Health; D005260:Female; D006801:Humans; D007221:Industry / Q000706:statistics & numerical data; D007558:Italy / Q000453:epidemiology; D008297:Male; D008654:Mesothelioma / Q000453:epidemiology / Q000209:etiology*; D008875:Middle Aged; D012042:Registries
D001194:Asbestos