Module 4: Asbestos And Disease - Note (Continued)

A BRIEF HISTORY OF ASBESTOS RELATED DISEASES:

The first case of asbestosis was described in the UK in 1906, but industry studies of fibrosis occurred only in the 1930s. Between 1890 and 1930 asbestos usage became firmly established in industry.

A possible association between asbestos and lung cancer was raised in 1935, based on the observation of a relatively high mortality from lung cancer among workers with asbestosis. This association was accepted in Germany in the 1940s. A study by Doll in the UK in 1955 found a ten-fold excess of lung cancer among asbestos workers, an association confirmed by Selikoff in the 1960s in a study of insulation workers in the USA.

In 1961 Wagner et al. published a report of 33 cases of malignant mesothelioma, all from the Northern Cape, and almost all with known asbestos exposure. This was an exceedingly rare tumour in the general population, although there had been scattered reports through the 1940s and 1950s. Although only a case series, this paper became a classic and contributed to acceptance of the causal link between asbestos and this rare disease.

Asbestos is perhaps unique in the extent of litigation that has followed from its impact on health. In the USA product liability suits directed at suppliers of asbestos (not at the employers of affected workers) has run into billions. Stimulated by the needs of litigation, research was able to document a conspiracy by the asbestos and insurance industries in the USA to suppress or delay results from studies on the toxicity of asbestos.

More recently, legal history was made when former workers of the British company, Cape plc, in the Northern Cape (having long ago sold its interests in South Africa) won the right to sue the existing parent company in Britain. The result was a settlement now being administered by a trust in South Africa. Further asbestos suits are expected in South Africa. In these legal processes, the testimony of clinicians and epidemiologists have played an important role.

Asbestos was used so widely in industrial and commercial settings during much of the 20th century that the number of people exposed runs into many millions. While new amphibole use in recent years has been stopped in most countries (and all asbestos types banned in some countries), chrysotile asbestos continues to be mined, notably by Canada and Russia (and Zimbabwe), and exported for use as a relatively cheap building material. Chrysotile thus remains of economic importance and at the centre of fierce contestation over its safe use, including international campaigns by the industry, (supported by their governments as in the case of Canada), to have "controlled use" of chrysotile declared safe. In the face of these campaigns, affected workers and other parties have mounted legal and other campaigns for compensation, and activists have advocated for increasing restrictions and an ultimate ban on its use.

South Africa was slow to incorporate information about risk into protective practices. Mesothelioma became a compensatable disease under the Workmen’s Compensation Act only 1979 and the first asbestos regulations were promulgated by the Department of Labour only in 1986! Control in the mining sector took place earlier as the government mining engineer applied administrative standards which resulted in reduced exposures over time. Attention was focused on asbestos pollution of mining areas, that is, the Northern Cape and the then North-Eastern Transvaal, only in the 1980s.

These delays in converting scientific information into regulatory and other control measures resulted in probably tens of thousands of cases of disease and premature death. The asbestos industry played a role in limiting research or its dissemination and the government of the day did little to challenge this. By contrast, individual medical practitioners and activists played an important role in detecting and publicising cases of asbestos related disease.