The long and winding road from silica exposure to silicosis and other health effects

• silicosis
• silica

Technological advances over the past half century, including wet drilling and improved ventilation, have contributed to substantially reducing the occurrence of silicosis among miners and other dust exposed workers. Hundreds of cases are, however, still identified each year in Europe and the USA,1,2 and silicosis is a major threat for workers in developing countries. Low salaries and less restricting and/or less enforced occupational hygiene standards have attracted many environmentally and occupationally demanding productions,3 and facilitated mining initiatives in developing countries.4

On the other hand, the “reappearance” of silicosis in wealthy western countries has resulted from the extension of occupational health surveillance to previously under scrutinised small or family owned businesses, and the immigration and illegal employment of non-unionised workforce from developing countries. Furthermore, the progressive clearing of the dark and thick cloud of silicosis cases, has been accompanied by the emergence of other diseases such as lung cancer, kidney failure, and immune system disorders,1 which has rekindled the interest in silica research.

“The interaction between physical and biological entities is complex”

As in many other fields of science, it seems that the more we progress in knowledge, the more we realise the complexity of the interaction between physical and biological entities. Such a complexity is viewed differently from different perspectives, as reflected by the diverse philosophy underlying the OSHA dust permissible exposure limit, which is flexible depending on the silica content in respirable dust (5 mg/m³ in the absence …