Introduction Stone quarry workers are constantly exposed to crystalline silica dust of different particle sizes in different concentrations.

General objective To determine the effects of stone dust on respiratory health of stone quarry workers in Sri Lanka.

Methodology Respiratory symptoms of quarry workers(n=79) from different sections of industry were assessed followed by a clinical examination. Spirometric indices were recorded prior to a Monday work shift and air borne dust levels were measured.

Results Workers had a mean work duration of 53 months and an average of 4.2 pack years of smoking. Regarding the respiratory symptoms, 10.1% and 11.4% workers complained of morning and nocturnal cough, respectively. While 2.5% workers had Haemoptysis and 30.4 % workers complained of wheezing, 30.4 % and 5.1 % had Grade II and III dyspnoea respectively. One subject showed evidence of fibrosis on clinical examination. Lung function tests showed a restrictive pattern in 24 (30.4%) workers and among them 16 had above normal exposure to dust. Obstructive pattern is seen in 9 (11.4%) subjects with 4 being exposed to higher dust levels. There is a statistically significant relationship with duration of work, type of work and the level of dust exposure with the clinical features(p<0.001).

Conclusion There is a decline in the lung function which is related to the duration of work and amount of dust exposure. It mainly shows a restrictive pattern of impairment.