Pollution Characteristics And Human Exposure Of Per-and Polyfluoroalkyl Substances(PFAS) In Petrochemical Parks

Pe-and polyfluoroalkyl substances(PFAS)are a class of synthetic compounds,which benefit from their excellent surface activity,chemical stability,and thermal stability.It is widely used in industrial production and daily life fields.At the same time,the negative impact on environment and human caused by PFAS has attracted wide attention.The adverse impacts from PFAS have triggered the supervision and alternative actions on PFAS worldwide.Previous research on PFAS focused on the water environment,such as estuaries,coasts,and lakes,etc.In addition,many studies have focused on the surrounding environmental media of fluoropolymer factories and fluorinated chemical factories and a few reports on areas and places where PFAS is used.PFAS are widely used in the petroleum industry,high concentrations of legacy and novel PFAS are detected around oil drilling and storage sites.The petrochemical industry is an important part of the petroleum industry.This has greatly influenced the scientific understanding of PFAS.Therefore,a Petrochemical Park in Dongying,Shandong Province was selected as the research object,systematically collected environmental media and human body samples around the petrochemical park and analyzed the concentration levels and pollution characteristics of legacy and novel PFAS in environmental samples.The main results of the thesis research are as follows:(1)legacy and novel PFAS were generally detected in the environmental media of petrochemical parks,and the concentration range of ∑PFAS in soil was 1.09-22.39 ng/g.PFOA,PFOS and OBS were the dominant pollutants.The ΣPFAS concentration in groundwater ranges from 3.15 to 17.0 ng/L,with PFOA and OBS were the major contaminants,while the PFAS concentration in fish ranges from 16.30 to 272.68 ng/g ww,with PFOS,OBS and 6:2 Cl-PFESA were the major contaminants.The ∑PFAS,PFOS and OBS contents in the soil of the refinery are significantly higher than those in the soil surrounding the refinery,and the ∑PFAS,PFOS and OBS contents in the soil are significantly correlated with the distance from the sampling point to the factory.The lower the content is,the higher the content of ∑PFAS is in the groundwater of the residential area.Besides,the ∑PFAS in the groundwater of residential areas decrease significantly with the increase of well depth.The BAF calculation of PFAS in fish showed that PFOS,PFDA and 6:2 Cl-PFESA had bioaccumulation.The bioaccumulation capacity of 6:2 Cl-PFESA was the highest,while the bioaccumulation capacity of OBS was relatively weak.The BAF of PFCAs increased with the increase of carbon chain length.The results of soil source analysis determined that there were three different types of pollution sources.namely,oil and fabric industry emission pollution,material emulsification and atmospheric deposition pollution,and packaging pollution.MLR calculated that the contribution rates of the three pollution sources were51.3,28.4 and 20.3%,respectively,and the soil in the factory was most affected by oil and fabric industry emission pollution.Health risk assessment results indicate low risk of local population exposure to PFAS through drinking groundwater.(2)The concentrations of ∑PFAS in whole blood of petrochemical workers ranged from 6.32-115.89 ng/m L,PFOA,PFOS and 6:2Cl-PFESA are the dominate pollutants,the concentration of PFCAs is much higher than that of PFSAs and the detection rate of long chain PFAS and the contribution rate of ∑PFAS are greater than that of short chain PFAS.The concentrations of ∑PFAS in urine ranged from 100.94-2516.25 ng/L,PFPe A and PFBA were dominant compounds in urine,the detection rate and contribution rate of ∑PFAS in urine were higher than those in long chain PFAS.The contents of PFAS in whole blood and urine were different with sex,age,working age and BMI,and the contents of ∑PFAS,PFOA,PFNA,PFHx S,PFOS and 6:2 Cl-PFESA in whole blood of male workers were significantly higher than those of female workers(P<0.05).The urine level of PFOA in male was significantly higher than that in female(P<0.05).The age of workers was positively correlated with the whole-blood ∑PFAS and PFOA(P<0.05),while the working age of workers was positively correlated with the whole-blood ∑PFAS only(P<0.05),and no correlation was found between the urine of workers and the age and working age.In addition,the total blood PFAS content was significantly increased with the increase of BMI(P<0.05),but the urine had little change.Calculation of renal clearance using whole blood and urine concentrations paired by petrochemical workers found that,the median renal clearance rate of PFAS was 0.028-28.182 m L/day/kg.The renal clearance rate of PFOS was the lowest,PFPe A was the highest,and the renal clearance rate of short chain PFAS was higher than that of long chain PFAs.The clearance rate of PFCAs,a homolog of the same chain length,was higher than that of PFSAs,and the clearance rate of male PFAS was lower than that of female PFAs.