Measurement and Evaluation on Indoor Air Quality in Two Types of Public Places in Tianjin, China

Indoor air quality in a large supermarket and a classroom building in Tianjin was investigated through the spectrophotometric method and solvent desorption-gas chromatography.Health risks of staff in the two public places were assessed through the inhalation exposure method.In the supermarket,the concentrations of formaldehyde in the washing products and cooked food areas are obviously higher than those in other areas,and the maximum concentrations of benzene and toluene simultaneously appear in the shoes area,whereas their minimum values occur in the household appliances area.In the classroom building,the concentrations of benzene ranges from 3.74 to 13.0 μg/m³,whereas the levels of toluene are not more than 6.34 μg/m³.Lifetime cancer risks of exposure to benzene for male and female staff in the supermarket are 1.32×10^-4 and 9.23×10^-5,respectively,whereas those for male and female teachers in the classrooms are close to 1×10^-6.