Study On Air Pollution Characteristics Of Phthalate Esters And Its Association With Particulate Matters

Phthalates ester（PAEs）in indoor air is one kind of the semi-volatile organic compounds（SVOCs）.They are widely used in building decoration materials and plastic products.They are easily adsorbed to particulates,dust,indoor surfaces and even human skin surfaces.There are three ways for PAEs to enter the body,dust ingestion,inhalation（gaseous and particulate phases）and dermal contact with the gaseous phase of air,then participate in human metabolism,finally resulte in damage to the respiratory system,reproductive system,and endocrine system.This paper mainly studies the pollution characteristics of PAEs in indoor air in residential buildings in Harbin and its relationship with particulate matter.Firstly,the concentration levels of gas phase and particle phases PAEs in student dormitory,office,and residential indoor air in Harbin were tested on site,and their pollution characteristics were analyzed.The results showed that the mean concentrations of PAEs in the air of the three buildings were:54.03,46.69,and 47.95μg/m³,and the pollution degree was the most serious in the student dormitories,followed by the residence and the office.There is no significant concentration difference in the male and female dormitories,and only a few high molecular weight PAEs male dormitories are high.The main pollutants in the office were DEHP and DCHP,but DEPP was not detected.The concentration of gas phase and particle phases DiBP in the residential indoor air was the highest,with mean values of 2576.0 ng/m³and 4595.6 ng/m³ respective.DMP was not detected in the residential.Secondly,the partition coefficient of the gas phase and particle phases in residential air was estimated.The results showed that the range of logK_p for the 15 PAEs ranged from-1.58 to-0.67.At the same time,the concentration of particulate matter measured at the site was analyzed and it was found that the concentration of particulate matter during the test did not change much and basically in a stable state.Then,based on the mass concentration and counting concentration of particulate matters,the relationship between particle phase PAEs and particulate matters was analyzed.The concentration of particle phase PAEs was positively correlated with the mass concentration of the particles,and the concentration of particles phase PAEs was positively correlated with the small particle concentration.In addition,the residence time of the particulate matter was calculated based on the mass concentration of the particulate matters and the CO₂ concentration measured in the field,and the relationship between the particulate matters residence time and the PAEs of the particulate phase was analyzed.Finally,according to the measured gas phase and particle phase concentrations and the human parameters consulted,the measurement formulas were used to calculate the external exposure levels and the carcinogenic risk of PAEs in different buildings.It was found that inhalation exposures in student dormitories,offices and homes were all greater than skin exposures,and exposures decreased with age.The risk of DEHP carcinogenicity in the female dorms aged 16 to 21 is 2.35×10^-5,far exceeding the human cancer risk limit of 1×10^-6.