Respiratory Health and Silica Exposure of Stone Carvers in Thailand

Abstract

A cross-sectional study of dust exposures and health outcomes was conducted in a stone-carving company in Thailand. 147 respirable dust samples were collected and 97 subjects participated. Exposure indices were constructed and health outcomes, including respiratory symptoms, pulmonary functions, and chest radiographs, were assessed. Severities of employees' current exposures to quartz were 0.5-8.8 times the ACGIH-TLV, depending on job and site. Durations of exposures ranged from 4 months to 30 years. The prevalence of silicosis (profusion grade > or = 1/0) was 2%. Pulmonary tuberculosis was also detected in 4%. Linear regression analyses revealed decreased lung function in workers with longer work durations (p < 0.05), regardless of age, sex, height, and smoking status. No clear association was seen between cumulative exposure metrics and indicators of silicosis. Elevated silica exposure levels indicate an ongoing risk of silicosis in this industry. Exposures were increased by the use of grinding tools with no ventilation and by proximity to other workers. However, because the number of workers with dust-exposure histories was limited, exposure measurements were confined to current conditions.

High-Resolution CT in Silicosis

“…3 Several studies have shown that HRCT has a higher sensitivity than chest radiography in the detection of coalescence of small opacities 4,5 and in the identification and quantification of emphysema. [13][14][15][16][17][18][19] The aim of this study was to assess the HRCT findings of silicosis in stone carvers and to better define the role of CT in the early detection of silicosis. 12 There are few studies reporting silicosis among workers of the lapidary industry, and none of them used HRCT in the evaluation of these workers.…”

Assessment of Respiratory Health Issues Among Stone Carvers of Rajasthan, India

“…In the same way, an Indian study by Ahmad 26) found that mine workers in Rajasthan were more likely to have chest infections and coughs. Yingratanasuk et al 22) stated a higher occurrence of cough and phlegm among stone carvers in Thailand. Similarly, Nwibo et al 27) noted that Nigerian stone workers had a greater incidence of respiratory problems such as cough and chest infections.…”

“…These workshops are home-based industrial units that involve 10-20 carving workers at a single working site. Such workers are often migrant-type, needing more employment records or health and social security benefits 22) . The usual respiratory issues among stone carving workers were not noticeable in recent literature.…”

Assessment of Respiratory and Pulmonary Functions of Glass Blowers

“…In comparisons to ball makers, mold handlers and helpers, blowers have a high prevalence rate of cough (62.16 %), chest pain (56.75), dry, scratchy or sore throat (48.64 %), body aches (45.94 %). The other reported problems were tight chest (32.43 %), A study conducted by Yingratanasuk et al, (2002) on stone carvers in Thailand also reported the most common respiratory symptom in the carvers was phlegm (26.8 %), followed by cough, dyspnea, chronic bronchitis, and wheeze (16.5 percent, 12.4 percent, 6.2 percent, and 4.1 percent, respectively). Mortar makers at Location II and III also reported a high prevalence of phlegm (42.1 percent and 50 percent, respectively).…”