Establishment Of Four Kinds Of Risk Factor Detection Technologies And Their Application In E-commerce Aquatic Products

In the context of the Internet,the E-commerce industry has penetrated into every aspect of people's lives,from traditional clothing,home,daily necessities and other industries to food and agricultural products including aquatic products.Facing with the challenges of Ecommerce products quality supervision,the government revised and improved many relevant laws,regulations and norms,so that the e-commerce industry is gradually becoming standardized.However,due to the particularity of sampling,evidence collection,traceability,and accountability,E-commerce aquatic products have many blank spots and weak links in quality supervision.This paper draws on the sampling detection and risk monitoring of the production,processing and circulation of aquatic products in traditional offline transactions,and establishes four kinds of risk factor detection technologies to study high-risk Ecommerce aquatic products with hidden dangers of quality and safety.The specific research contents are as follows:(1)In 2017,89 batches of samples were sampled from mainstream E-commerce platforms such as Taobao,Tmall,Jingdong and Suning Tesco,and 74 batches of samples were taken in 2018,totaling 163 batches.Sample types include fish,shrimp,crabs and snack foods.During the sampling process,we found some problems,such as the merchant refused to sample,could not issue invoices or inconsistent invoice information,and the actual product information and online promotional information did not match.(2)Inductively coupled plasma mass spectrometry(ICP-MS)was used to simultaneously measure eight harmful elements such as Cr,Ni,As,Cd,Sn,Pb,V and Co in E-commerce aquatic products.Each has a good correlation in each linear range,r2 was greater than 0.999,and the measured values of 8 harmful elements in the quality control sample were within the standard value range,and the RSD(n=6)was less than 4.51%.This method is suitable for routine analysis of the content of harmful elements in E-commerce aquatic products.Sample test showed that electricity suppliers Portunus trituberculatus sold on line samples higher Cd content,so we focus on the assessment of Portunus trituberculatus sold on line samples Cd content and dietary risk.The risk assessment showed that the Cd dietary exposure in Portunus trituberculatus sold on line was lower than the provisional tolerable monthly intake(PTMI)recommended amount(25 ?g/kg b.w.),and the target hazard quotient(THQ)values were all less than 1,which indicated the low risk of Cd contamination in Portunus trituberculatus sold on line.Nevertheless,due to Cd being a long half-life in the organism,there is still a health risk if people ingest large quantities of Portunus trituberculatus sold on line for a long time.(3)Establishing a method for the determination of 10 estrogens in E-commerce aquatic products by dispersive solid phase extraction-ultra performance liquid chromatographytandem mass spectrometry(DSPE-UPLC-MS/MS).The sample is extracted by acetonitrile,salted out by Na Cl,concentrated by nitrogen blowing,reconstituted with methanol/water(1:1,v/v),purified by adding N-propyl ethylenediamine solid phase adsorbent(PSA),and centrifuged,the supernatant is separated by ACQUITY UPLC BEH C18 column,and progesterone and estrogen are measured by multiple reaction monitoring in electrospray positive and negative ion mode,respectively.The results showed that the linear relationship of 10 estrogens in the range of 1.00-50.0 ?g/L was good,r2 was greater than 0.997.The average recoveries of 10 estrogens at 3.00,5.00,20.0 ?g/kg 3 spiked levels ranged from 79.4% to 110%,and RSD(n=6)was less than 6.04%.The method is simple and rapid,uses less organic solvent,has high sensitivity and good repeatability,and is suitable for daily detection of 10 estrogens in E-commerce aquatic products.(4)The ionic liquid(IL)used as the extraction solvent for the liquid-liquid microextraction(DLLME),and then the content of Rhodamine B,alkaline yellow O,alkaline orange 21 and alkaline orange 22 in the E-commerce aquatic product determined by ultra performance liquid chromatography(UPLC).The key parameters affecting the extraction efficiency were optimized,such as the type and amount of ionic liquid,centrifugation time,vortex time,temperature,etc.,compared with ultrasound assisted-temperature controlled(UA-TC)-IL-DLLME,vortex-assisted(VA)-IL-DLLME.The experimental results show that the linearity of the four basic dyes was good in the range of 5.00~200 ?g/L,r2 was greater than 0.999,the recovery rate was between 90.2% and 107%,and the RSD(n=6)was less than 5.83%.The method is simple,quick,green,reproducible and low in cost,and is suitable for daily detection of four basic dyes in E-commerce aquatic products.(5)To explore the possibility of applying the characteristics of the element composition and stable isotopes of trichiurus haumela sold online its traceability of geographic origin,the stable isotope ratios(?13C and ?15N)and multi-element(Na,Mg,K,Ca,Mn,Fe,Cu,Zn,As,Sr)contents of 24 batches of trichiurus haumela sold online were determined by liquid chromatography-isotope mass spectrometry(LC-IRMS)and ICP-MS,trichiurus haumela sold online origins included Lvsi Fishing Ground,Zhoushan Fishing Ground,Qinghai Fishing Ground,Minnan Fishing Ground.Based on the differences in their stable isotope ratios and elemental composition,a discriminant model was established based on cluster analysis(CA)and principal component analysis(PCA)to trace the origin of trichiurus haumela sold online in the four regions.Analysis of variance(ANOVA)showed that the stable isotope ratios and elemental composition of trichiurus haumela sold online in each area had obvious regional characteristics,and the contents of the nine elements were significantly different.CA indicated that the correct discrimination rate of the sample origin was 83.3%.PCA shows that the scattered points of the first three principal components(the cumulative variance contribution rate is 82.0%)are divided into four relatively concentrated areas without any overlap with each other,and can effectively distinguish the origin of trichiurus haumela sold online.In summary,the use of stable isotopes and multi-element detection combined with CA,PCA can effectively trace the origin and discriminate of trichiurus haumela sold online,has certain feasibility and application value.(6)Monitoring the risk factors of harmful elements,estrogens,basic dyes,origins,additives and labels in 163 batches of E-commerce aquatic products according to the established methods and relevant national standards.Analysis of risk monitoring results,combined with the current status of E-commerce aquatic product quality,found that China's aquatic products E-commerce industry has product standardization and lack of branding,merchants are not strict with product quality,E-commerce platform has not played a role and the relevant laws are not sound and other issues.Only by strengthening the branding of Ecommerce aquatic products,improving the quality of E-commerce aquatic products,playing the role of E-commerce platform supervision,and innovating the government supervision mechanism can we better promote the quality supervision of E-commerce aquatic products in China and make China's E-commerce aquatic products The quality is guaranteed to be safer.