Surveillance And Risk Assessments Of Marine Biotoxins In The Qingdao Market

Objective: 1.To establish a method for the determination of 14 hydrophilic shellfish toxins and 11 lipophilicn shellfish toxins in shellfish products collected from the Qingdao,Chinese Market.2.To determine and analy assessment the content and the distribution of shellfish toxins in different kinds of shellfish(Concha Ostreae?Venerupis variegata?Sinonovacula constricat canarck,Patinopectenyessoensis,Chlamysfarreri,Mylilussiccus,Scapharca subcrenata,Busycon canaliculatu,Cerithidea obtusa Lamarck,Neptunea cumingi Crosse and Monodonta)which sell on the market.Methods:1.Method of determination of 14 hydrophilic shellfish toxins and 11 lipophilicn shellfish toxins in shellfish.The samples were extracted with 1% acetic acid,and the graphitized carbon black solid phase extraction column was purified.The liquid chromatography-tandem mass spectrometry(LC-MS/MS)was used to determine the paralytic shellfish toxin and the external standard method.Lipophilicn shellfish toxins(LPs,including OA,DTX1,DTX2,PTX1,PTX-2,AZA1,AZA2,AZA3,GYM,SPX1,and YTX)were prepared by direct extraction of 100% methanol and C18 solid phase extraction column.45-OH-YTX,45-OH-Homo YTX,OH-Homo YTX and DA were matrix calibration and external standard quantification.2.Determination of 14 hydrophilic shellfish toxins and 11 lipophilicn shellfish toxins in shellfish products collected from the Qingdao,Chinese Market.A total of 400 samples of shellfish were collected from the aquatic products wholesale market in Qingdao,including Concha Ostreae,Venerupis variegata,Sinonovacula constricat canarck,Patinopecten yessoensis,Chlamysfarreri,Mylilussiccus Scapharca subcrenata,Busycon canaliculatu,Cerithidea obtusa Lamarck,Neptunea cumingi Crosse and Monodonta labio.And the results were analyzed by solid phase extraction combined with liquid chromatography-tandem mass spectrometry(LC-MS / MS).3.Survey of the dietary consumption.Adopting multistage and stratified sampling,a total of 1104 residents in Qingdao were adopted for investigation of 24-hour dietary questionnaire.We collected six categories of food consumpution for three consecutive days and recorded consumption with data entry bookkeeping.4.The result of analysis.The types and contents of shellfish toxins in the samples were calculated and the distribution of shellfish toxin in different time samples was analyzed.The daily dietary exposure of dietary intake of shellfish toxins was calculated using the daily exposure method and risk assessment was performed.Results:1 The limits of detection of 25 kinds of shellfish toxics were from 2 ug/kg to 711ug/kg(S/N=3).The average recovery was 85.2 %~108 % and the precision ranged from 1.8 % to 7.6 %.2 Content distribution of shellfish toxics in different varieties with time changing,and risk assessment.2.1 Comparison of different shellfish toxics in different samples.In this study,a total of 400 samples were tested in 12 batches,of which 73 were detected and the shellfish diarrhea shellfish toxin was found,the detection rate was 18.50%.Among them,the main components were okadaic acid(OA),pectenotoxin-2(PTX-2)and YTXs(Yesssotoxin),other types of shellfish toxins have not been detected.The samples were found to be mainly scallops and mussels,and the remaining samples were not detected.The positive detection rate of shellfish samples showed a certain difference with time.The detection rate of diarrhea shellfish was the highest in shellfish samples from May to August.OA detected the highest rate in August,reaching 29.20%,YTX in August the highest detection rate of up to 26.80%,PTX-2 in July the highest detection rate of up to 35.20%,of which the highest content of PTX-2 7.189?g / kg,no other shellfish toxins have been detected.2.Risk assessment.The amount of fat-soluble shellfish toxin OA,PTX-2 and YTX in the consumption of shellfish was 0.48,0.88 and 0.65 respectively.According to the level of food consumption,especially in summer and autumn,OA acute poisoning Events,long-term high-dose exposure which may be a threat to health.The consumption of shellfish containing YTX is within the safe range,and there are no other risks.Conclusions:1 This method is fast,stable and simple,with high average recovery rate.The high sensitivity,precision and accuracy of the method can meet the testing requirements for the qualitative and quantitative determination.2 The type and content of phthalic acid esters varies in different foods,sampling sites andseasons.3 Nowadays,the pollution of shellfish toxics has covered the shellfish.According to the content of shellfish toxics,we can find that it is impossible to add intentionally,and there is no risk for people's daily life for now.But we should further research whether long-term shellfish toxics pollution impact on humans.