Article Text
Abstract
Objective This study was conducted to estimate the prevalence of respiratory symptoms/illnesses and the magnitude of silica exposures among children working in Nepalese brick kilns.
Methods Personal samples for silica were collected following NIOSH methods. Bivariate and multivariate logistic regression analysis was carried out to evaluate association between respiratory symptoms/illnesses and participant groups (exposed and referent) and Similar Exposure Groups (SEG) among brickfield workers. Logistic regression analysis adjusting age, duration of work and smoking practices was carried out at 0.05 level of significance. Additionally, a cross-sectional study was conducted in Kathmandu valley targeting all the brickfield workers during February – March 2015. Out of 106 operating brick kilns in Kathmandu Valley, 16 kilns were selected for the study applying multi-stage probability proportionate to size (PPS) sampling technique. A total of 800 participants, 400 brick workers as exposed and 400 grocery workers as referent group were recruited for interviews.
Results A total of 86 silica samples, 10 were linked to children under the age of 18. These children worked in several of the SEGs. Among the SEGs, red brick loaders had the highest mean and maximum exposures to silica. Chronic cough (14.3%), phlegm (16.6%) and bronchitis (19.0%) were higher (p<0.05) among brickfield compared with grocery workers (6.8, 5.8 and 10.8%). Mean respirable (5.888 mg/m3) and total (20.657 mg/m3) dust exposures were highest for red brick loading tasks. Additionally, several SEGs had workers under the age of 18. Exposure were significantly high and results will be discussed.
Conclusions High dust exposures identified in this study may explain the increased prevalence of respiratory symptoms/illnesses among Nepalese children working in the brickfields, warranting action to reduce exposures.