Human breath as a source of VOCs in the built environment, Part I: A method for sampling and detection species

Humans occupy and form the centerpiece of the built environment. However, humans have been traditionally treated as passive receptors in the context of the environment. Growing evidence indicates that humans could be an important source of volatile organic compounds (VOCs), especially in relatively crowded environments such as aircraft cabins and conference rooms. In this work, a method and a corresponding apparatus for analyzing VOCs in exhaled breath were developed. A total of 117 healthy human subjects were recruited and their breath samples were collected and analyzed for major VOC species. The average number of VOC species in each exhaled sample was 49.3, ranging from 11 to 98. The majority of common VOCs were alkanes, followed by oxygenated compounds such as aldehydes and ketones. In addition to common VOCs, emissions from different subjects were found to have highly individual characteristics. The study offers a method suitable for large-scale sampling and analysis of VOCs from human exhaled breath. Results obtained from this study could provide necessary information about humans being considered as indoor pollutant sources under specific conditions.