Cement dust is very alkaline and irritant, and also usually contains chromate in a form that can cause sensitisation (unless iron is added as in Scandinavia). It sounds as if your patient has developed irritant induced asthma (sometimes called reactive airways dysfunction syndrome). The criteria for this include being normal before the exposure (as in your patient), having an acute exposure (as in your patient), having airflow obstruction whose onset is within 24 hours of the acute exposure (and usually much sooner, as in your patient), and having symptoms and bronchial hyper-responsiveness which persist for more than 3 months. It is not very usual to get worse 2 months later, however. Irritant induced asthma can be caused by many overwhelming exposures, it does not lead to sensitisation, and the affected individual is left with asthma which does not deteriorate with subsequent low dose exposure, so the usual job can usually continue. There are a few individuals who develop allergic occupational asthma from cement dust, usually thought to be due to the chromate. Acute exposures can occasionally lead to subsequent sensitisation, in which case subsequent low dose exposures can cause deterioration in the asthma and removal from further exposure is warranted. The problem with cement dust is that some workplaces have quite high exposures, there is some literature implicating cement dust as a cause of occupational COPD. I would have thought that any form of acute silicosis was very unlikely, but would welcome others views. Some references are attached.
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9.Abou-Taleb AN, Musaiger AO, Abdelmoneim RB. Health status of cement workers in the United Arab Emirates. Journal of the Royal Society of Health 1995;115(6):378-81.
10.De Raeve H, Vandecasteele C, Demedts M, Nemery B. Dermal and respiratory sensitization to chromate in a cement floorer. Am J Industr Med 1998;34(2):169-76.
11.Leroyer C, Dewitte JD, Bassanets A, Boutoux M, Daniel C, Clavier J. Occupational asthma due to chromium. Respiration 1998;65(5):403-5.
12.De Raeve H, Vandecasteele C, Demedts M, Nemery B. Dermal and respiratory sensitization to chromate in a cement floorer. Am J Industr Med 1998;34(2):169-76.
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