Abstract:

Objective To investigate the pollution status of common chemical pollutants in the indoor air of public places in four cities of Shaanxi Province and analyze the health risks to the employees. Methods In 2023，samples of chemical pollutants（formaldehyde，ammonia，benzene，toluene，and xylene） in the indoor air of three types of key public places，namely hotels，barber shops，and beauty salons，in four cities of Shaanxi Province were collected and tested. The exposure levels of indoor air pollutants were analyzed. The health risk model recommended by the United States Environmental Protection Agency（USEPA） was adopted to evaluate the health risks of chemical pollutants in the indoor air of public places to the employees. Results The indoor air contents of benzene，toluene and xylene in all kinds of public places did not exceed the standard，and the over-standard rate of formaldehyde was 3.81%，4.17% and 2.13%，respectively，with no statistically significant difference（χ²=0.383，P>0.05）. The over-standard rate of ammonia in barbers was 5.56%. Formaldehyde in indoor air of different places all posed carcinogenic risks to employees，with a median concentration of 10^-6 to 10^-4 and a maximum concentration of >10^-4. The carcinogenic risk of benzene in all kinds of places was relatively low，the risk value of the median concentration was <10^-6，and the risk of the maximum concentration was >10^-6. The median concentration HQ of formaldehyde in the indoor air of hotels，barbershops and beauty shops were >1. There were 238（56.67%），40（55.56%） and 25（53.19%） monitoring points HQ>1 in the 3 types of places，respectively. The HQ of benzene，toluene，xylene and ammonia in indoor air in various places were <1. Conclusion Formaldehyde in indoor air in public places has carcinogenic risk and non-carcinogenic risk to employees，and benzene has certain carcinogenic risk，which should be paid attention to.

Key words: Public place, Chemical pollutant, Health risk