Ez Chelkowska

Changes in the geographical and temporal patterns of cancer incidence among black gold miners working in South Africa, 1964–1996

We describe here the results of the final 8 years of geographical and temporal data of a 33-year study of the cancer experience of 12.8 million man-years of black miners working on the gold fields of South Africa over the period 1964–96. These workers were recruited from 15 territories, the major areas during the most recent period being Lesotho (26.8%), Transkei (21.5%) and Mozambique (15%). The earliest analyses, 1964–71 and 1972–79, showed hepatocellular and oesophageal cancers to be the most frequent cancers. The final analysis, for 1989–96, however, shows marked temporal changes in the relative position of four cancers or grouped malignancies: respiratory cancer up by 236%, hepatocellular carcinoma down to 32%, oesophageal holding steady, and lymphatic system cancers up by 420%, almost certainly because of association with HIV/AIDS infection. Significant geographical variations occurring between the home areas of the miners are important, as mining operations have little to do with the cancers that develop. The causes are essentially socio-environmental rather than occupational, and this means that the rates of the major cancers in the miners are surrogate measures of the same cancers in the home areas.

Auger spectroscopy for molecules: Tables of matrix elements for transition-rate calculations corresponding to an s-, p-, or d-type initial hole

Abstract Auger transition rate matrix element expressions for molecules based upon s, p, and d atomic basis sets to describe the valence molecular orbitals are presented for processes involving s-, p-, or d-type initial holes. The expressions are tabulated in terms of the real and imaginary parts of the singlet and triplet components for the various allowed continuum channels. Auger transition rates for molecules may be calculated within an intra-atomic model using these expressions and published atomic Auger matrix elements (M. H. Chen, F. P. Larkins, and B. Crasemann, Atomic Data and Nuclear Data Tables, 41, 1, 1990) . Values from the latter relevant to the present work are also tabulated. An example is presented for the Cl(L23-VV) spectrum associated with the HCl molecule.

South Africa's export trade in asbestos: Demise of an industry

BACKGROUND South Africas export of each of its three types of asbestos, crocidolite, amosite, and chrysotile, and the total amounts to 84 countries in metric tonnes is examined over a 24-year period, 1980-2003. METHODS For convenience, the countries are divided into nine world regional groups, Europe, Eastern Europe, North America with the Caribbean, South America, Africa, Middle East, Far East, South Asia, and Oceania. RESULTS The three greatest importing countries of total asbestos in metric tonnes were all in the Far East region, ranging from Japan, South Korea to Thailand, and followed by USA and Italy. All exports to all countries diminished steadily as the South African trade came virtually to an end by 2003, due to ever increasing international pressure. CONCLUSION The export trade has changed significantly since 1960 from being dominantly to European countries to being directed in recent years to the Far East, with serious implications for asbestos-related ill-health in those countries.