INTERESANTE COMENTARIO SOBRE SILICOSIS AMBIENTAL:Respiratory Disease and Sandstorms in the Middle East

David F. Goldsmith, MSPH, PhD:

I have researched some of the concerns about "ambient silicosis" from Middle East and Asia sources, and find the evidence wanting. Yes, there is some clinical and environmental support for idiopathic pulmonary fibrosis (IPF) from serious investigators in New Mexico. However, there has been a tendency to look at dust storms as the likely culprit, with concern that elevated levels of silica in ambient dust in arid regions of the world as the answer. This is also relevant to soldiers serving in the Middle East. Along with my colleague at the EPA--Dr. Jeff Gift--looked at this in the 1990s (here is the cite--Gift J and Goldsmith DF Ambient Levels and Noncancer Health Effects of Inhaled Crystalline and Amorphous Silica. Health Issue Assessment for Office of Research and Development, U.S Environmental Protection Agency, Washington DC (EPA/600/R-95/115), November, 1996).

With a bit more digging, it appears the "silicosis among female Bedoins" might be related to women's exposures to fumes and partuclates from cooking fires, in confined spaces such as tents (and caves in the cases from the Central Asia). Thus, in all cases, before attribution to silica in dust storms, the patients need to be asked if they cook/work/raise children close to cooking fires. If they respond in the negative, then dust storms could be investigated for their role in IPF. However, I too think the particle sizes from desert dust storms are too large for depostion in the alveoli. It is paticulate matter (PM) < 10 microns which is necessary for silicosis. In my opinion, silicosis remains a workplace disease and not an envrionmental one.

David F. Goldsmith, MSPH, PhD

Associate Research Professor

Department of Environmental & Occupational Health George Washington University 2100 M Street NW, Suite 203 Washington DC 20052 USA

Tel: 202-994-1734; fax 202-994-0011

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website: http://www.OccupationalEpi.com