OCCUPATIONAL EXPOSURE TO NATURALLY OCCURRING ASBESTOS (NOA)

Asbestos occurs naturally through geologic processes and can be found throughout much of the world. It is clear that mining of asbestos, the manufacture of asbestos products and the use of asbestos products has been associated with disease. There is some suggestion that working with asbestos containing rocks and soils may also have contributed to disease. Concerns have been raised in populations that have encountered naturally occurring asbestos (NOA) in their local environment. The situation is further complicated by controversies regarding the toxicity of other fibrous minerals or fragments of non-asbestiform varieties of asbestos minerals. Mining and quarrying are local sources of dust that may contain asbestos or other elongate mineral particles, but less obvious commercial activities, such as construction and farming, and even some recreational activities, can also result in exposures and thus potential risks for disease. Communities traditionally have had to come to terms with their local environment and its potential hazards to health, especially when acute and well-known, such as flooding or earthquake. However, a more complex relationship can occur with more insidious and long-term risks. NOA has implications for amenity use and property values, as well as health, and this can also result in social and political stress within a community. In addition, the process of risk communication and management can be muddled by uncertainties and conflicts of interests as well as by differences in perception and acceptance of risk. Asbestos and related minerals are commonly encountered in the mountain ranges in the both the east and west sides of the North American continent. As populations extend into these areas, NOA will be increasingly encountered. Occupational risks to miners and quarrymen and also construction workers and farmers need to be assessed and, where necessary, controlled. However, there are also potential risks to others outside of these specific occupations. Therefore, occupational hygiene professionals, including toxicologists, epidemiologists and risk assessors, work together with geologists and environmentalists to ensure a holistic approach to the issues of NOA.