Airborne Particulate Matter and Health Condition in Brick Kiln Workers in Kathmandu Valley, Nepal.

Background Air quality monitoring in brick kilns indicates very high concentrations of airborne particulate matter. Air pollution from brick kilns poses an enhanced threat to the environment and to human health. Objective To evaluate airborne particulate matter concentration and health status of brick kiln workers. Method A cross-sectional comparative study was conducted in the Kathmandu valley targeting all brick industries and their workers during January - March 2015 and March - April 2016. A total of 16 brick kilns and 800 participants (400 brick workers as exposed and 400 grocery workers as referent) were selected for study. A direct-reading, Dusttrak model 8533 was used for air sampling. Nepali version questionnaire was applied to obtain epidemiological data. SPSS version 16 was used to perform statistical analysis. Median, mean, range and proportion were calculated and Mann-Whitney U test, Kruskal-Wallis test and chi square (c2) test were applied to test significance. Result Mean values of particulate matter concentrations for brickfields were as follows: Total Suspended Particulate Matter (TSPM): 5.179 mg/m3, PM10: 4.958 mg/m3, respirable suspended particulate matter (RSPM): 4.140 mg/m3, PM2.5: 3.965 mg/m3, and PM1: 3.954 mg/m3. The mean concentrations for grocery workers were; TSPM: 0.089 mg/ m3, PM10: 0.089 mg/m3, RSPM: 0.085 mg/m3, PM2.5: 0.082 mg/m3 and PM1: 0.082 mg/m3. Among brickfield workers, red and green brick loading zones had results that exceeded the ACGIH Threshold Limit Values for TSPM and RSPM. Workers complaints of injury were 52% and 44.2%, and illnesses were 88.5% and 82.2%, respectively among exposed and referent. The occurrence of injuries/illnesses during work showed significant association between exposed and the referent groups at 0.05 level. Conclusion The high level of airborne particulate matter in the brick fields requires action for the protection of workers. The availability of health services within brick industries needs to be enhanced.