In the vast majority of the cases of mesothelioma in South Africa where there was known to have only been environmental exposure to asbestos, this exposure has occurred in the Northern Cape in proximity to mines, mills and dumps.
A high proportion of cases of environmental origin (26.6%) is unique to South Africa. The only comparable example is Australia, the only other country to have mined crocidolite in significant amounts. Ferguson et al. found that in 726 cases of mesothelioma registered in Western Australia during 1980–85, 43 cases or 6% had environmental exposure only, and only in six cases (<1%) was environmental asbestos exposure due to residence in an asbestos mining region (Wittenoom).
Webster9 and Solomons12 do not detail the source of environmental exposure to asbestos of the patients in their series but in a later series that included these and other environmental cases totalling 100, Webster gave the following distribution: 93 cases originated from exposures in relation to mining in the Northern Cape; 3 in relation to amosite and Transvaal crocidolite in the Northern Province; and in the balance there was some uncertainty about the exact source of exposure. Cochrane Rees et al.have detailed environmental exposure in a further 25 cases, 23 from the Northern Cape, and most could recall some asbestos exposure. In Rees’ series one case was in a teacher who had worked in asbestos cement classrooms in 1934–75.
Another was a policeman in the Northern Province who made regular trips to asbestos mines. The authors are aware of a medical colleague who died of mesothelioma in his mid-40s whose exposure was a childhood in the Northern Cape as a son of a local general practitioner. In summary, 93% of all environmental mesothelioma cases in South Africa originate from exposures in relation to crocidolite mining activities in the Northern Cape.
A high proportion of cases of environmental origin (26.6%) is unique to South Africa. The only comparable example is Australia, the only other country to have mined crocidolite in significant amounts. Ferguson et al. found that in 726 cases of mesothelioma registered in Western Australia during 1980–85, 43 cases or 6% had environmental exposure only, and only in six cases (<1%) was environmental asbestos exposure due to residence in an asbestos mining region (Wittenoom).
Webster9 and Solomons12 do not detail the source of environmental exposure to asbestos of the patients in their series but in a later series that included these and other environmental cases totalling 100, Webster gave the following distribution: 93 cases originated from exposures in relation to mining in the Northern Cape; 3 in relation to amosite and Transvaal crocidolite in the Northern Province; and in the balance there was some uncertainty about the exact source of exposure. Cochrane Rees et al.have detailed environmental exposure in a further 25 cases, 23 from the Northern Cape, and most could recall some asbestos exposure. In Rees’ series one case was in a teacher who had worked in asbestos cement classrooms in 1934–75.
Another was a policeman in the Northern Province who made regular trips to asbestos mines. The authors are aware of a medical colleague who died of mesothelioma in his mid-40s whose exposure was a childhood in the Northern Cape as a son of a local general practitioner. In summary, 93% of all environmental mesothelioma cases in South Africa originate from exposures in relation to crocidolite mining activities in the Northern Cape.
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