Contamination Characteristics, Source Analysis And Health Risk Assessment Of PAEs In Commercial Food In Northwest China

Phthalate esters(PAEs)have been widely used in industrial fields since the 1930s.PAEs are only bond to other substances by physical effects and maintain themselves physical and chemical properties.Therefore,they are easily released into the natural environment during the production and consumption.However,as a class of environmental endocrine disruptors(ECDs),PAEs have adverse effects on ecosystem function and public health.Consequently,the pollution characteristics,environmental behaviors and health risks of PAEs have been gradually concerned by scholars.At present,most of researches on PAEs at domestic and foreign are limited to 6 priority compounds.However,with the in-depth study of PAEs and the development of toxicology,it has been found that some non-priority PAEs have high detection and concentration,and they have certain health hazards.Dietary exposure is one of the most important pathway for human beings to ingest PAEs,accounting for more than 50%of the total exposure(bis(2-ethylhexyl)phthalate DEHP is 100%).Up to now,the PAEs dietary exposure risk of residents in northwest China is still in a blank state.Therefore,a systematical study on the pollution characteristics and health risks of priority/non-priority PAEs in foods in the Northwest region is of great significance for diet safety.This paper determined the concentrations of PAEs in foods in the Northwest region(Xi'an city and Lanzhou city)by liquid-liquid extraction(LLE)with equipment gas chromatography-mass spectrometry(GC-MS),and studied their pollution characteristics.Then,the paper discussed the pollution characteristics of PAEs in different types of food as a case of Xi'an city in detail,identified the possible source of PAEs in food and put forward relevant suggestions.In fact,the total concentrations of PAEs are only partically absorbed by human body,so artificial pollution and physiologically based extraction test(PBET)methods were utilized to obtain the bioa-vailability of PAEs.Ultimately,the health risks to 9 PAEs compounds(dimethyl phthalate DMP,diethyl phthalate DEP,diisobutyl phthalate DiBP,di-n-butyl phthalate DnBP,butyl benzyl phthalate BBP,bis(2-ethylhexyl)phthalate DEHP,di-n-octyl phthalate DnOP,diisononyl phthalate DiNP and dissodecyl phthalate DiDP)were evaluated by assessment models with the optimizing parameters.The following findings are mainly obtained:In comparison to other methods and laboratory conditions,a sample pre-treatment method for mass analysis,i.e.,liquid-liquid extraction(LLE),was used to extract the concentration of PAEs in solid and liquid samples,and the conditions of gas chromatography-mass spectrometry(GC-MS)were optimized.The verification of the methodology showed that the sample processing method and instrument conditions could meet the experimental requirements.22 PAEs were detected in food samples in Northwest China to varying degrees.Among them,DiBP was the individual PAEs with the highest detection rate(Xi'an:81.61%;Lanzhou:92.31%).The total concentration of 22 PAEs(?22PAEs)was 0.0340?56.8021 ?g/g(mean value:3.7047 ?g/g).The concentrations of ?22PAEs in Xi'an and Lanzhou city were in the range of 0.0340?56.8021 ?g/g and 0.0808?14.6647?g/g,with an average/median of(mean value:3.9379 ?g/g,2.1443 ?g/g;median value:0.4763 ?g/g,0.6069 ?g/g)were relatively close.Except for DMP,di-n-propyl phthalate DPrP,bis(4-methyl-2-penthl)phthalate BMPP,DEHP.and DiNP,the contents of 17 compounds in Xi'an were higher those of Lanzhou.There were inter-species difference in the different foods(?22PAEs):meat(Xi'an:18.8649 ?g/g,Lanzhou:7.5794 ?g/g),eggs(15.4218 ?g/g;14.6647 ?g/g),vegetables(8.0677 ?g/g;3.4795 ?g/g),fruits(3.9715 ?g/g;1.0349 ?g/g)were relatively heavy polluted by PAEs in Northwest China,while dairy products(0.1759 ?g/g;0.1019 ?g/g)and beverages(0.1556 ?g/g;0.1883?g/g)were slightly polluted.From the perspective of the composition characteristics of PAEs,DiBP,DnBP,DEHP,DiNP,DiDP were the main pollutants,accounting for 90.3%of the ?22PAEs(Xi'an city)and 94.02%(Lanzhou city)of the total concentration.It showed that when the 6 priorty PAEs are concerned,the non-priorty PAEs with various types and high detection rates should also be paid more attention to avoid potential health risks caused by long-term exposure.Principal component analysis(PCA)and cluster analysis(CA)indicated that the growth characteristics of raw materials(water,atmosphere,soil environmental media)and human intervention(plastic contact)together caused the polluted foods by PAEs.In addition,it had a certain relationship with the physical and chemical properties of PAEs,the final composition(lipid)of foods and the storage environment(temperature,humidity,etc.).The results of bio-availability of 22 PAEs(8 solid food samples in Xi'an)showed that the gastro-intestinal bio-availability of PAEs(DEHP 33.42%?DMEP 74.39%)was always higher than that of the gastric phase(DiDP 5.89%?DMEP 44.54%)and intestinal phase(DiDP 7.09%?DMEP 46.12%),and the bio-availability of bis(2-methoxyethyl)phthalate(DMEP)was the highest among the three phases(gastro-intestinal phase 74.39%,gastric phase 44.54%,intestinal phase 46.12%).As the molecular mass of PAEs increases,the bio-availability had a slight downward trend,and the 6 priority PAEs had a more obvious trend(from 69.17%of DMP to 36.87%of DnOP).Similarly,the octanol-water partition coefficient(Kow)was also negatively correlated with the gastro-intestinal bio-availability of PAEs,while solubility and vapor pressure showed a significant positive correlation.For different types and functions foods,although the external conditions(pH,temperature and so on)were consistent,the bio-availability of PAEs still presented different rules.In the present study,the health risks of PAEs were assessed by two methods.The calculation results of national food consumption data showed that expect for DEHP(Xi'an:3.0513 ?g/kg bw/d;Lanzhou:7.2309 ?g/kg bw/d)and DiNP(Xi'an:2.5456?g/kg bw/d,Lanzhou:4.3055 ?g/kg bw/d),the estimated daily intakes(EDIs)to the rest of PAEs in Xi'an were higher than that of Lanzhou.And the EDIs of DMP,DEP,BBP,DnOP were lower than other provinces in China,while DnBP and DEHP were within the range.The same conclusion could be drawn with reference to provincial food consumption data.However,due to the difference in reference food consumption data between provinces and the national consumption data,there was no direct comparison significance.Overall,the EDIs of 9 PAEs were all lower than the corresponding limits,and the values were at the domestic normal level.Based on the analysis of national consumption data with consistent food,it found that cereals(Xi'an:64.47%,Lanzhou:30.1 1%)and vegetables(Xi'an:21.14%,Lanzhou:33.17%)were the major sources of dietary exposure to PAEs in Northwest China.Considering the limitations of available data,only the non-carcinogenic risk of 6 priority PAEs and the carcinogenic risk of BBP and DEHP were evaluated.The results showed that all non-carcinogenic risks of 6 priority PAEs were lower than the critical value of 1.When the parameter of DnBP was used to calculate the non-carcinogenic risk(HQ)of DBP(DiBP+DnBP),the HQ of DBP in foods in Lanzhou(0.8561)and Xi'an(1.3216)was close to the critical value and exceeded the critical value,respectively.Furthermore,the carcinogenic risk(CR)of BBP was less than 10-6(Xi'an:4.71 × 10-8;Lanzhou:2.51 × 10-8),the CR value of DEHP was between 10'6 and 10-4,and Lanzhou(1.01 × 10-5)was higher than Xi'an(4.27 × 10-6).The calculation results used the consumption data of Xi'an and Lanzhou also suggested the non-carcinogenic risk was lower than the critical value,the carcinogenic risks of BBP(3.77 × 10-8;1.09 ×10-8)and DEHP(2.71 × 10-6;4.33 × 10-6)were less than 10-6 and between 10-6 and 10-5.As a result,the population health risks by PAEs of foods in the Northwest region was relatively low.