ObjectiveTo assess the level of internal exposure to PCP in a community population in Shanghai， to investigate the factors affecting the level of PCP， and to analyze the correlation between the exposure and thyroid hormone levels. MethodsA total of 464 residents of a community in Shanghai were selected as the study subjects. A questionnaire survey was conducted to obtain the demographic information， dietary situation， lifestyle and behavioral habits， and disease history of the individuals， and blood samples were collected. Gas chromatography-electron trap was applied to determine the PCP levels in serum. Multicategorical logistic regression analysis was used to analyze the possible influencing factors of PCP exposure in humans. Thyroid hormone levels were used as the dependent variable and serum PCP as the independent variable. Multiple linear regression analysis was used to assess the association between PCP and thyroid hormones in the community population after controlling the confounding factors such as age， gender， literacy， annual personal income， and chronic diseases. ResultsThe detection rate of serum PCP in 464 subjects was 90.3%， and the median serum PCP level was 0.43 μg·L^-1. The differences in PCP levels among different age groups were statistically significant. There were no significant differences in PCP levels among different gender and BMI groups. The study of PCP exposure factors showed that age， frequency of using plastic products， consumption of freshwater fish， type of occupation， annual income， and consumption of tea or coffee were the potential influencing factors for PCP exposure. Among them， age， frequency of using plastic products， consumption of tea or coffee， and consumption of freshwater fish were positively associated with PCP levels， and annual personal income was negatively associated with it. The results of multiple linear regression analysis showed that among men， PCP levels were positively correlated with TSH （b=0.105， 95%CI：0.017‒0.313） and negatively correlated with FT4 （b=-0.026， 95%CI：-0.057‒0.004）， and among women， PCP levels were positively correlated with TSH （b=0.092， 95%CI：-0.211‒0.904） and FT3 （b=0.017， 95%CI：-0.058‒0.230） and negatively correlated with FT4 （b=-0.013， 95%CI：-0.011‒0.037）. ConclusionSerum PCP detection is common among community residents in Shanghai. Different demographic characteristics or behavioral habits may increase or decrease PCP exposure. PCP exposure then affects human thyroid hormone levels.

ObjectiveTo investigate the characteristics of serum perfluoroalkyl substances （PFASs） exposure and potential influencing factors among community residents in Songjiang District， Shanghai. MethodsIn August 2021， residents who underwent routine health checkups in a community in Songjiang District， Shanghai were recruited as study subjects. The inclusion criteria were adult residents who had lived in the area for more than 3 years， had no occupational exposure history， no underlying diseases， were not pregnant， and were able to complete the questionnaire independently and sign the informed consent form. A questionnaire survey was conducted and venous blood samples were collected. The concentrations of 15 PFASs in serum were determined using ultra-high performance liquid chromatography-tandem quadrupole mass spectrometry （UPLC-MS/MS）. Ordered multi-class logistic regression， interquartile range （IQR）， and odds ratio （OR） were used to explore the influencing factors and risk magnitude of serum PFASs concentrations. ResultsOf the 15 PFASs， 14 were detected， and the detection rates of 7 PFASs were higher than 50%. The highest detected concentrations among the PFASs were PFOS （perfluorooctane sulfonate）， PFOA （perfluorooctanoic acid）， and PFHxS （perfluorohexane sulfonate）， with median concentrations of 48.61 μg∙L^-1， 37.29 μg∙L^-1， and 36.51 μg∙L^-1， respectively. The strongest correlation was between PFDA and PFUnDA （r=0.93， P<0.05）， followed by PFOS and PFDA （r=0.86， P<0.05）. Age， frequency of plastic product use， time spent indoors per day， personal annual income， tea consumption， and daily water intake were potential factors for exposure to PFASs. Among them， age was positively correlated with PFASs； tea consumption was positively correlated with PFNA and PFOA； PFHpA was negatively correlated with the frequency of plastic product use and personal annual income； and PFOS was negatively correlated with the time spent indoors per day. ConclusionThe exposure to serum PFASs among community residents in Songjiang District was relatively serious， and the main components were traditional PFOA， PFOS， and PFHx. Different sociodemographic characteristics had varying degrees of influence on the concentrations of PFASs in serum. The impact of PFASs exposure on the health of community residents deserves further investigation.