Silicosis surveillance in ontario: Detection rates, modifying factors, and screening intervals

The Province of Ontario has had a surveillance program for workers in dusty industries for almost 70 years. This paper reports the detection rates of silicosis among 68,701 silica-exposed individuals who were first exposed to dust in 1950 or later, and who were still employed in 1979 or later. The detection rate varied strongly with latency, being less than two new cases per 10,000 examinations during the first two decades from first exposure, …