Asbestos Bodies Burden in the Autopsy Lung Tissue from General Thai Population.

BACKGROUND: Chrysotile asbestos has been used in Thailand for over 30 years mainly in asbestos-cement wall and roof tiles. In non-exposed subject, asbestos fiber can contaminate in ambient indoor and outdoor environments. OBJECTIVE: The aim of the present study is to evaluate the current prevalence and volume of AB load in general Thai population. METHODS: Lung tissues were obtained from 200 autopsy cases. Asbestos Bodies (AB) were identified with light microscopy using the tissue digestion and membrane filtration method. Results are reported as AB/g wet lung tissue. RESULTS: AB was identified in 97(48.5%) out of 200 cases. The AB level ranged from 0.19-14.4 AB/g wet lung. Most of the positive cases (99%) have less than 10 AB/g wet lung. Only one case exhibited a high value at 14.4 AB/g wet lung. Age, gender, occupation and hometown were found to have no effect on AB burden in autopsy lung tissue from this study. CONCLUSION: The prevalence of AB in autopsy lung tissue from general Thai population is 48.5% and the AB level ranges from 0-14.4 AB/g wet lung in consistent with non-occupational asbestos exposure level regarding several reference reports.

Plasma adipokine levels in Thais.

OBJECTIVE: To assess three plasma adipokines that might act as biomarkers useful in determining persons exposed to asbestos. METHOD: Sixty subjects were included in the study, 30 male workers from factories manufacturing cement products using chrysotile asbestos, and 30 volunteer controls comprising 15 men and 15 women. Fasting venous blood specimens were submitted for blood chemistry examination and analysis of plasma levels of three adipokines, i.e. adipsin, adiponectin and resistin. RESULTS: (1) Compared with non-obese subjects, the adiponectin levels were lower in obese subjects, resistin levels were higher, and hemoglobin concentrations were lower. (2) Adipsin levels in the workers were significantly higher than in the controls (p < 0.005), and this difference was not related to body fat. (3) There were no statistically significant differences in adiponectin, resistin, and adipsin levels between the male and female controls. (4) Adiponectin in the male controls was significantly higher than that in the male workers (p <0.05). (5) Female controls had significantly higher percentages of body fat (p < 0.0005) and resistin (p < 0.02) levels than male controls and male workers. (6) A significant negative correlation existed between resistin and hemoglobin levels levels (r= -0.336, p < 0.01). (7) Overall adipsin levels among male workers were significantly higher than among control subjects (p < 0.005); the six workers in whom asbestos bodies (AB) were detected did not have significantly higher levels of adipsin than those of workers without AB having been detected. CONCLUSIONS: Although the findings apparently showed higher adipsin levels in the workers, its value as a biomarker for asbestos exposure requires confirmation from studies on a larger group of subjects.

Determination of asbestos bodies in bronchoalveolar lavage fluids in Thailand.

OBJECTIVE: Asbestos bodies (AB), ferroprotein-coated asbestos fiber may be present in bronchoalveolar lavage fluid (BALF) of asbestos exposed persons. The present study was conducted to evaluate the prevalence and number of asbestos bodies in the BALF of tenable asbestos exposed workers compare to general population in Thailand. MATERIAL AND METHOD: Thirty workers of cement pipe and roof tile factories using chrysotile asbestos and 30 unexposed patients that underwent diagnostic bronchoscopy were included in this study. Determination of asbestos bodies was made by membrane filtration method as described in earlier reports. RESULTS: The findings were positive in six workers and in one control subject (0.1-3.6 vs. 0.2 AB/ml of BALF, p = 0.449). CONCLUSION: AB was identified in workers more often than in pulmonary disease patient. Two of workers had more than 1 AB/ml of BALF.

Free-living ameba contamination in natural hot springs in Thailand.

Thermo tolerant free-living ameba, Naegleria spp and Acanthamoeba spp contamination in natural hot springs in Thailand were carried out from 13 provinces. The temperature of hot springs water varied from 28 degrees-65 degrees C and pH from 6-8. We found that 38.2 % (26/68) of water samples were positive, Acanthamoeba was 13.2% (9/68) whilst Naegleria was 35.3% (24/68). Contamination by free-living ameba in natural hot springs may pose a significant health risk to people who use such water for recreation activities.

Spa, springs and safety.

Natural mineral water has long been used worldwide for bathing and health purposes. At present, Thailand is famous for health spas and natural hot springs among local people and tourists. Due to possible risks of exposure to harmful agents, we studied hazardous pollutants at 57 natural hot springs from 11 provinces in northern, central, eastern and southern Thailand. Pathogenic, free-living amebae of the genera Naegleria and Acanthamoeba, which can cause central nervous system infection, were found in 26.3% (15/57) and 15.8% (9/ 57), respectively. Dissolved radon, a soil gas with carcinogenic properties, was present in nearly all hot springs sites, with concentration ranging from 0.87-76,527 Becquerels/m3. There were 5 water samples in which radon concentration exceeded the safety limit for drinking. Legionella pneumoniphila (serogroups 1, 3, 5, 6, 7 10 and 13) were found in samples from 71.9% (41/57) of studied sites. Because spas and natural springs are popular tourist attractions, health authorities should be aware of possible hazards and provide tactful measures and guidelines to ensure safety without causing undue alarm to foreign and Thai tourists.