No abstract

Thus, these four cancers accounted for 75-1% of the total number of cases.Brief accounts of the spatial and temporal distribution of primary liver cancer and oesophageal cancer were given by Harington and McGlashan (1973a, b).In the present investigation, geographical definition of the patterns of distribution of the four major sites of cancer was sought in the belief that statistically significant gradients, together with changes in the cancer rates in the course of time, could provide a basis for future research programmes directed at aetological implications.METHOD OF SURVEY AND BASIC DATA (i) Areas of recruitment of the population at risk.-The health problems and environmental background of African workers in the South African gold mines were described by

Summary.-Data on the incidence of cancer of the oesophagus in the Transkei for years 1965-69 are presented, age specific rates for the sexes discussed and the spatial relationship of well-defined regions of high and low incidence demonstrated.

SUMMARY A geographical pathology survey of a large area in central Africa is described and a contrast is recognized between neighbouring areas with apparently many and apparently few cases of oesophageal cancer. This distribution is compared first with other known areas of high and low incidence in sub-Saharan Africa and then with the drinking of indigenous types of distilled spirits. A significant order of spatial correlation is shown between the geographical pattern of the disease and the drinking of sugar-based alcoholic spirit in central Africa. Samples of spirits from eastern Zambia, central Kenya, and the Transkei, although prepared in apparently dissimilar utensils, were all shown to be contaminated in varying degree with zinc. Nitrosamine-like compounds in native spirits were also reported in all these areas.The need for a geographical survey of indigenous drinking habits in Africa is illustrated. Since legislation against distilling is ineffective, a simple means of excluding carcinogenic compounds from illicit spirits should be ascertained and widely promulgated at village level.For several years it has been recognized that carcinoma of the oesophagus has a remarkable geographical distribution in Africa. Recent reports (Ahmed, 1966;McGlashan, 1967; Oettle, 1963a) emphasize the difference of incidence in qualitative terms but data have usually been collected only for small areas, often a region familiar to one medical officer, and it is rare to find numbers of cases related to the population at risk to allow quantitative comparison with other areas.Statistical data of the type described by Doll (1967) are not available for most of Africa and are unlikely to be produced for another generation.

Production and export figures of South African asbestos were analyzed over 1959–1993. They show stable sales of chrysotile. Those of crocidolite and amosite reached their peaks in the mid‐1970s, after which trade fell drastically, crocidolite to 5% of its earlier peak and amosite to nil. Factors responsible for these virtual collapses were health issues, stricter legislation in First World countries, and litigation. In 1992, 21 countries continued to import crocidolite, although in reduced quantities. In the early 1960s, Europe and North America were the major recipients of South African asbestos. By 1989–91, these regions were surpassed by the Far East, which took over 90% of chrysotile and 70% of amosite. For crocidolite at that time, the Middle East took nearly 40%, Europe 28%, and Africa 21%. This implies that the newly importing countries can confidently expect an increase in asbestos‐related disease and death well into the twenty‐first century, even if the trade ceased now. Am. J. Ind. Med. 33:321–326, 1998. © 1998 Wiley‐Liss, Inc.