Research describes the development of a simple, low-cost passive air sampler for monitoring indoor air pollution in China. Air quality in China is a hot topic, with air pollution rivalling food safety and clean drinking water as a key theme for Chinese lawmakers.
Scientists at Tsinghua University have developed a system for testing the air in indoor environments for the volatile organic compounds benzene, toluene and xylene (BTX), which are common indoor air pollutants in China that can have chronic adverse health effects on humans. There are currently few data on indoor BTX concentration levels because of a lack of cost-effective sampling techniques.
The scientists developed a passive sampler suitable for long-term sampling using hydrophobic silica zeolites as an adsorbent, because they have a large capacity for adsorbing BTX and they are compatible with thermal desorption – the method used to transfer samples from the sampler to GC-MS for analysis. They tested the device in the laboratory, taking into account various environmental factors including wind temperature and humidity. They also evaluated the device under real conditions and showed that it was comparable with currently used commercial active samplers, which are more expensive and require power supplies and human attendance.