Characteristics of indoor/outdoor particiculate pollution in urban and rural residential environment of Pakistan

摘要

Particulate pollution has emerged as a serious environmental health concern in Pakistan. The use of biomass fuels in traditional stoves produces high levels of indoor air pollutants. In Pakistan, 94% of rural and 58% of urban households depend on biomass fuel. This study investigates variations in indoor/ outdoor concentrations of particulate matter during various activities for three different micro-environments in Pakistan. At a rural site, the average indoor/ outdoor ratios for PM_(10), PM_(2.5), and PM_1, in kitchens using biomass fuels were 3.80, 4.36, and 4.11, respectively. A large variation was recorded in the mass concentration of particulate matter during cooking with concentrations in the range 4000-8555 μg/m~3. In a living room at a rural site, the average indoor/ outdoor ratios for PM_(10), PM_(2.5), and PM_1 were 1.74, 2.49, and 3.01, respectively. At the urban site, the average indoor/outdoor ratios for the same size fractions were 1.71, 2.88, and 3.47, respectively. Cooking, cleaning and smoking were identified as principal contributors to the high indoor levels of particulate matter. This study showed considerably high concentrations of particulate matter, particularly in kitchens using biomass fuels, as compared to living areas. Thus women and children face the greatest exposure due to the amount of time they spend in the kitchen.