Phthalate Pollution In Window Film Of College Dormitories In Beijing And Exposure Assessment

Phthalates?PAEs?plasticizers are currently the most widely used plasticizers,and can be detected in indoor air,dust,food and other media.They have become an important new indoor environmental pollutant and are related to the human health.Existing domestic researches are mostly focused on the research of PAEs in dust-reducing media,and there are few literatures using window film media for research.Window film,as an adsorption medium for PAEs,has a certain accumulation,and is a new way to study the exposure of PAEs in indoor environments.This paper can enrich domestic PAEs pollution data from a new perspective and promote the formulation of relevant standards.In this study,the indoor window film of the student dormitory of the Beijing scientific research institution was selected as the research object.Using statistical principles,the pollution characteristics of the concentration of PAEs in the window film were analyzed.14PAEs were detected in 145 window film samples,and the detection rate of DIBP,DBP,DEEP,DCHP,DEHP,DNOP and DNP are 100%.The highest concentrations of DMP,DEP,DIBP,DBP,DMEP,DMPP,DEEP,DPP,DNHP,BBP,DCHP,DEHP,DNOP,and DNP are 128,99,212,812,209,44,1512,89,361,28,2352,2625,456 and 1060?g/m².The data of Shapiro-Wilk test is non-normal distribution,and there is a significant correlation between the components of PAEs with similar molecular weights in Spearman test?P<0.05?.DIBP,DPP,DNHP,DCHP,DEHP and DNP have significant differences between different urban areas?P<0.05?.DEP,DIBP,DMEP,DEEP,DCHP,DEHP,and DNOP have significant differences between different genders?P<0.05?.BBP and DNOP have significant differences in different orientations?P<0.05?.Repeated measurements of multivariate analysis of variance showed that the change in?PAEs concentration of male and female dormitory with time was statistically significant?P<0.05?without considering the interference of other influencing factors.By recording the basic information of the samples and issuing questionnaires,a total of23 factors that may affect the concentration level of PAEs are counted,including the indoor and outdoor environment,the number of interior decoration materials and furniture,and personal habits.The contingency table chi-square test was used to screen the above factors,and the 17 suspected influencing factors were analyzed by binary logistic regression analysis,and finally 13 main factors affecting the concentration of PAEs in the window film were determined.Geographic location,light intensity,window orientation,indoor temperature,indoor relative humidity are the main environmental factors that affect the concentration of PAEs in the window film.Increasing the floor cleaning frequency and windowing ventilation frequency can effectively reduce the concentration of PAEs in the indoor environment.Daily necessities,personal care products,household appliances,wires and other equipment,interior decoration materials and furniture coatings are the main sources of PAEs in indoor environments.Generalized Linear Mixed Model determines that the orientation,indoor PM₁₀concentration,indoor temperature,indoor humidity,and light intensity can all affect the concentration of some PAEs,and the degree of influence in male and female dormitory is different.Indoor temperature and indoor humidity are factors that affect the concentration of?PAEs.The model was established using octanol-air partition coefficient(K_OA),and the concentration of PAEs in the gas phase,particulate phase and dustfall in the indoor environment was calculated based on Monte-carlo simulation.DEP has the highest gas-phase median concentration of 8160ng/m3.The gas particle distribution results of PAEs show that PAEs of small molecular weight are preferentially distributed to the gas phase in the air,while PAEs of large molecular weight are preferentially distributed to the particle phase,and as the molecular weight increases.Based on the exposure parameter manual of the Chinese population and the exposure parameter manual published by the US Environmental Protection Agency,a non-dietary exposure?inhalation,oral,skin contact?calculation model for humans was established based on Monte-carlo simulation.The median value of total exposure of DEP and DMP was higher,being 4504 and 3185ng/?kg·d?,respectively.As the molecular weight of the PAEs component increases,the main exposure pathway gradually transitions from skin contact to oral exposure.Through the risk index method?HI?in the cumulative risk assessment model to assess the human health risks of indoor PAEs exposure,there is a health risk in the exposure of PAEs in college students?HI=1.8?.Through the comprehensive risk system to evaluate the carcinogenicity of DEHP exposure in DEHP student dormitory,there is a certain carcinogenic risk of DEHP exposure in the dormitory among college students(CR=1.54×10^-6).