Exposure to Particulate Matter, Kathmandu Valley, Nepal

Abstract

PP-29-017 Abstract: Background/Aims: Air pollution, especially from traffic, is a serious problem in Kathmandu Valley. The project compared personal particulate matter (PM2.5) exposure and respiratory health based on occupation and roadway proximity. Additionally, temporal and spatial trends for ambient PM10 were examined. Methods: We investigated personal PM2.5 exposure and respiratory health for 3 groups: (1) traffic personnel (TP), (2) indoor officer workers near main roads (IOW_NMR), (3) indoor office workers away from main roads (IOW_AMR). At 3 locations (urban, urban residential, and semiurban), we recruited 6 TP, 3 IOW_NMR, and 3 IOW_AMR. For each participant, personal PM2.5 monitoring, time activity dairy, respiratory health questionnaire, and spirometer test was performed from 28 June 2009 to 7 August 2009. Traffic count was measured during peak traffic hours. Ambient PM10 data (2002–2007) from 6 government monitoring sites was assessed for temporal and spatial variation. Results: TP had the highest average PM2.5 exposure (50.16 μg/ma) with 78.3% of study days exceeding World Health Organization guidelines (25 μg/ma). The IOW_NMR average PM2.5 levels were 46.18 μg/ma, with 53.9% of days exceeding guidelines. The IOW_AMR had the lowest levels at 25.23 μg/ma, exceeding guidelines on 20.8% of days. Exposure was higher during morning rush hours than evening rush hours for all participant types and areas (71.9% of days for TP; 83.9% for IOW at urban settings). Similar prevalence of respiratory symptoms and lung function was observed across participant types. A weak association was noted between PM2.5 and lung function. Government PM10 monitors from 2003 to 2007 exceeded Nepal's daily PM10 standard (120 μg/ma) 48.8%–80.5% of days annually for inner and 3.36%–29.3% for outer city sites. Conclusion: High PM2.5 exposure was observed, with levels differing by location, time of day, and occupation. Findings indicate that air pollution is likely to have substantial health impacts in this region, especially for traffic police. A larger dataset is required to evaluate links between air pollution and health.