Respiratory symptoms and illnesses related to the concentration of airborne particulate matter among brick kiln workers in Kathmandu valley, Nepal

Abstract

BackgroundBricks have been manufactured in Nepal for hundreds of years and are seen as a component of Nepalese sculpture and architecture. Large quantities of hazardous materials including high concentrations of particulate matter are emitted on a daily basis from brick kilns. Exposure to these hazardous materials can lead to adverse consequences on the environment and human health. This study was conducted to estimate the prevalence of respiratory symptoms/illnesses and the magnitude of respirable and total dust exposures among Nepalese brick kiln workers.MethodsRespiratory symptoms/illnesses were evaluated by questionnaire among brickfield workers (n = 400) and a referent group of grocery workers (n = 400) in Kathmandu valley. Work zones (WZs): green brick molding (GBM), green brick stacking/carrying (GBS/C), red brick loading/carrying (RBL/C), coal preparation (CP) and firemen (FM) were the similar exposure groups (SEGs) from where personal air samples and interviews were taken. Among brickfield workers, personal monitoring was conducted across SEGs for total (n = 89) and respirable (n = 72) dust during February–March 2015 and March–April 2016. Applying multi-stage probability proportionate to size sampling technique, 16 kilns and 400 brick workers for interview were selected. Proportions, means, medians and ranges were calculated for the demographics, samples and respiratory symptoms/illnesses. One-way ANOVA was applied to compare the significance differences of the level of particulate matter among SEGs. Bivariate and multivariate logistic regression analysis were performed to evaluate association between respiratory symptoms/illnesses and participants groups, and SEGs among brick kiln workers at 0.05 level. Statistical analyses were performed using IBM SPSS Statistics 21.ResultsChronic 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. The prevalence of chronic cough, chronic phlegm, chronic bronchitis, wheezing and asthma were significantly higher for other WZs workers (p < 0.05) compared with CP; for GBM: 22.9, 34.6, 15.0 and 7.5%; for GBS/C: 13.5, 15.8, 10.0, 8.8 and 7.5%; for RBL/C: 11.1, 17.1, 27.4, 19.0 and 11.9%; for FM: 18.4, 12.5, 28.4, 4.9 and 0.0%; and for CP: 4.9, 6.3, 13.3, 9.3 and 4.0% respectively.ConclusionHigh dust exposures identified in this study may explain the increased prevalence of respiratory symptoms/illnesses among Nepalese brickfield workers, warranting action to reduce exposures.

The Threat of Ambient Air Pollution in Kathmandu, Nepal

“…Due to this pulmonary functions have been significantly worsened in the traffic police working in Kathmandu [ 53 ]. Airborne occupational hazards are equally present in brick kiln workers and grocery workers in Kathmandu, whose health has been seriously hampered and needs quick action for protection [ 54 , 55 ]. According to World Bank, air pollution stands as fourth major factor for causing death worldwide leaving metabolic risks, dietary risks, and tobacco smoking behind.…”

Comparison of Liquefied Petroleum Gas Cookstoves and Wood Cooking Fires on PM2.5 Trends in Brick Workers’ Homes in Nepal

“…However, there is little data specific to brick kiln workers, who represent a uniquely vulnerable and relatively large workforce in the Kathmandu valley. Brick kiln workers are at increased risk for respiratory diseases due to crowded housing [ 24 ], low socio-economic status, and occupational exposures associated with brick manufacturing [ 19 , 32 ]. Adding to these risks, the results presented in this study suggest that brick kiln workers and their families are potentially exposed to dangerously high levels of PM 2.5 during non-working hours.…”

“…A previous study conducted on the prevalence of respiratory illnesses among brick workers in Nepal shows that smoking was a significant predictor ( p < 0.001) of chronic bronchitis and chronic wheezing [ 19 ]. Of the world’s 1.1 billion global smokers, around 80% live in low- and middle-income countries [ 40 ].…”

“…In light of the already present risks of ambient and indoor air pollution, the possibility of HDMs within brick workers’ bedding presents an added health concern. We recommend further study investigating the presence of HDMs as a possible contributing factor to the high levels of respiratory problems among brick kiln workers in Nepal [ 19 , 32 ].…”

“…In the Kathmandu valley alone, there are over 100 brick kilns that employ approximately 30,000 workers in total [ 16 , 17 , 18 ]. Brick workers in Nepal experience high rates of respiratory symptoms, including chronic cough, chronic phlegm, chronic bronchitis, wheezing, asthma, dyspnea, and chest tightness [ 19 ]. These respiratory symptoms may be partially due to occupational exposures, particularly for dusty tasks such as moving red bricks from the kiln after they are fired [ 20 ].…”