Article Text
Abstract
Objectives Silicosis is a chronic lung disease caused by silica dust exposure and is a significant health problem in industry involving stone crushing process such as mortar and pestle production industry. We proposed a use of Heme Oxygenase-1 (HO-1) to detect an early stage of silicosis. HO-1 is a lung inflammation and oxidative stress biomarker which has a potential to indicate silicosis. In this study, the serum level of HO-1 in exposed subjects (stone mortar and pestle production workers) was compared to a non-silica exposed subjects.
Method Total crystalline silica was quantified by ultraviolet visible spectrometry. A chest radiograph was performed in a General Hospital by a trained radiologist to detect silicosis according to International Labour Organisation guideline. The serum HO-1 level was determined by sandwich enzyme immunoassay.
Results There were 19 silicosis subjects in the exposed group which was categorised into the silicosis group. The process in stone mortar and pestle production industry produced high level of silica dust in the air ranging between 3.97–21.12 mg/m3. The level of HO-1 increased as the level of silica exposure increased even after adjusted for smoking and employment duration. The level of serum HO-1 level was, however, not significantly different between silicosis, exposed, and non-exposed groups, nor was the relationship between HO-1 and pulmonary function.
Conclusions We propose that HO-1 reflects the lung inflammation caused by silica exposure although it is not specific to silicosis. HO-1 may be a useful parameter for monitoring lung inflammation in silica exposed population.