17 I. Zainab Z. Ali M. S. Ahmad Z. Zona S. T. Raza S. Safdar Z. A. Nasir I. Colbeck W. Liu Journal of Animal and Plant Sciences JAPS 20152015/06/01 25 3 433-435 1018-7081 NA Particulate matter exhibits different behavior with altitude. A comparative analysis was carried out to monitor PM 1, PM , PM , PM and PM at elevations above 3000 m in both China and Pakistan. Real time monitoring of PM was 2.5 4 10 Total carried out at both sites using a DustTrak DRX (model 8533, TSI Inc.) for 24 hours each. In Pakistan, the average value of PM was 415 + 16 µg/m3 while in China the value was considerably lower i.e. 110 + 57 µg/m3. The 24-hour mean Total values recorded were well above the WHO recommended limit of 25 µg/m3. These results indicate that, even at sites some distance from anthropogenic sources, PM concentrations still pose a health risk. countries is major contributor for indoor air pollution due NA Pakistan Agricultural Scientists Forum https://thejaps.org.pk/AbstractView.aspx?mid=2015-JAPS-667