Epidemiology of mesothelioma and historical background.

Mesothelioma is a "new" malignant disease strongly associated with exposure to amphibole asbestos exposure (amosite and crocidolite) environmentally and in the work place. Nonetheless, in recent years, we have learned that many cases of mesothelioma are idiopathic, while some are caused by therapeutic irradiation or chronic inflammation in body cavities. This paper reviews the key epidemiological features of the malignancy in the context of the biological and mineralogical factors that influence mesothelioma development. These tumors challenge the diagnostic pathologist's acumen, the epidemiologist's skill in devising meaningful and definitive studies, the industrial hygienist's knowledge of environmental hazards in diverse occupational settings, and the clinician's skill in managing an intrepid and uniformly fatal malignancy.

Chrysophiles versus chrysophobes: the white asbestos controversy, 1950s-2004.

In the first half of the twentieth century, asbestos was a controversial mineral because of its association with asbestosis and asbestos-related lung cancer. It has proved no less so since the 1960s, when another asbestos cancer, mesothelioma, was identified. Mesothelioma appeared to be more strongly linked with blue asbestos (crocidolite) than with the other asbestos varieties, brown (amosite) and white (chrysotile). This finding triggered a fierce debate between "chrysophiles" (those who declared chrysotile innocuous) and "chrysophobes" (those who believed it was a mortal hazard). This essay attempts the first history of the chrysotile controversy, which shows that a scientific consensus on the safety of white asbestos was very slow to emerge. This was only partly due to the complexities of scientific research. Political, economic, and social factors have militated against a speedy resolution of the debate, facilitating the continued production and use of asbestos in the developing world.