Air pollution in the microenvironment of parked new cars

Potential health effects of material emissions in new motor vehicles are of great public concern in China. To estimate the pollution levels, air samples were taken from 802 new cars parked in a well-ventilated underground parking garage in Beijing, China. These vehicles were all manufactured in and after 2003, and represented three different price ranges. For comparison, 20 older vehicles (manufactured before 2003) were also examined. Monitoring items included benzene, toluene, xylene, and formaldehyde. Preliminary results indicate that 82% of the vehicles studied had toluene levels exceeding the Chinese National Indoor Air Quality Standard. For benzene, xylene, and formaldehyde, the rates of noncompliance were 75%, 25%, and 24%, respectively. For all the pollutants, newer vehicles had higher concentrations than older ones. There seems a connection between the types of interior materials used in the passenger cabins and the concentrations of certain air pollutants.