Respirable dust and crystalline silica concentrations among workers at a brick kiln in Bhaktapur, Nepal.

Exposure to respirable dust and crystalline silica (SiO2) has been linked to chronic obstructive pulmonary disease, silicosis, cancer, heart disease, and other respiratory diseases. Relatively few studies have measured respirable dust and SiO2 concentrations among workers at brick kilns in low- and middle-income countries. The purpose of this study was to measure personal breathing zone (PBZ) respirable dust and SiO2 concentrations among workers at one brick kiln in Bhaktapur, Nepal. A cross-sectional study was conducted among 49 workers in five job categories: administration, fire master, green (unfired) brick hand molder, green brick machine molder, and top loader. PBZ air samples were collected from each worker following Methods 0600 (respirable dust) and 7500 (respirable crystalline SiO2: cristobalite, quartz, tridymite) of the U.S. National Institute for Occupational Safety and Health. Eight-hour time-weighted average (TWA) respirable dust and quartz concentrations were also calculated. SiO2 percentage was measured in one bulk sample each of wet clay, the release agent used by green brick hand molders, and top coat soil at the brick kiln. The geometric mean (GM) sample and TWA respirable dust concentrations were 0.20 (95% confidence interval [CI]: 0.16, 0.27) and 0.12 (95% CI: 0.09, 0.16) mg/m3, respectively. GM sample and TWA quartz concentrations were 15.28 (95% CI: 11.11, 21.02) and 8.60 (95% CI: 5.99, 12.34) µg/m3, respectively. Job category was significantly associated with GM sample and TWA respirable dust and quartz concentrations (all p < 0.0001). Top loaders had the highest GM sample and TWA respirable dust concentrations of 1.49 and 0.99 mg/m3, respectively. Top loaders also had the highest GM sample and TWA quartz concentrations of 173.08 and 114.39 µg/m3, respectively. Quartz percentages in bulk samples were 16%-27%. Interventions including using wet methods to reduce dust generation, administrative controls, personal protective equipment, and education and training should be implemented to reduce brick kiln worker exposures to respirable dust and SiO2.

Exposure to respirable silica among clay brick workers in Kathmandu valley, Nepal.

Previous studies report high respirable silica exposures among clay brick workers globally; however, there are little data on exposures among workers in fixed chimney Bull's trench kilns, the predominant kiln type in Kathmandu valley, Nepal. We investigated respirable silica exposures among workers (N = 46) in five similar exposure groups (SEGs). Mean exposures were highest for red brick loading/carrying (331 µg/m3), followed by green brick stacking (223 µg/m3), fireman (102 µg/m3), coal crushing/carrying (92 µg/m3), and green brick molding (71 µg/m3). The average free silica content (13.8%) in the respirable dust fraction was similar to levels reported for clay brick workers employed in other types of kilns. Dust control measures and respiratory protection are recommended, with priority given to workers assigned to red brick loading and stacking and green brick stacking and carrying.

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

BACKGROUND: Bricks 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. METHODS: Respiratory 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. RESULTS: 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. 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. CONCLUSION: High dust exposures identified in this study may explain the increased prevalence of respiratory symptoms/illnesses among Nepalese brickfield workers, warranting action to reduce exposures.

Attitude toward mental illness and psychiatry among the medical students and interns in a medical college.

INTRODUCTION: Medical students tend to have a neutral or negative attitude to Psychiatry as a discipline. This study was initiated to explore the attitude towards mental illness and Psychiatry among the medical students and interns in Kathmandu University School of Medical Sciences. METHODS: A cross-sectional questionnaire based study was conducted among the medical students and interns at Dhulikhel Hospital.Two self-rating scales; Attitudes towards Psychiatry-30 and Attitudes to Mental Illnesswere used to assess attitudes towards mental illness and Psychiatryamong the total 159 subjects. Descriptive statistics and independent sample t-test were applied using SPSS- 16 for analysis. RESULTS: Among the total 159 subjects, 44 (27.7%) were interns. Comparison of means of each item in Attitudes towards Psychiatry-30 and Attitudes to Mental Illnesswas done between males and females, medical students and interns, fi rst semester and ninth semester students. Most of the subjects showed neutral attitude towards all the scoring items; though there were a few signifi cant differences in mean scores of some items in group wise comparison. CONCLUSIONS: Overall attitudes towards mental illness and psychiatry among the medical students and interns in our medical school were positive or neutral. A further study with medical students from different institutions is needed to get a detail nationwide picture. KEYWORDS: attitude; interns; medical students; mental illness; psychiatry.