Distribution Of Lipophilic Marine Biotoxins Along The Coastal Area Of Guangdong Provice

Lipophilic marine biotoxins is a series of highly toxic biological toxins,which were produced by toxic marine microalgae or microorganisms.It could be enriched in marine organisms especially bivalves,and be serious harm to other organisms,even lead to the death of human beings.The study collected and determined 174 shellfish samples from 5 coastal areas of Guangdong Province(Shantou Nanao,Shanwei,Shenzhen Dapeng Bay,Zhuhai,Yangjiang Zhapo)during November 2013 to October 2015.And collected Crassostrea angulata and sea water samples in Shenzhen Dapeng Bay every month during July 2013 to October 2014(except July 2014).Then 15 lipophilic marine biotoxins in shellfish and water be detected by HPLC-MS/MS.The samples were analyzed according to aquatic food hygiene requirements of FAO,WHO,EU and China Fishery and Fishing Harbor Supervision.The study result would provide basic data to establish appropriate risk assessment system and appropriate monitoring programme of shellfish toxin for the relevant departments.The conclusions can be drawn as follows:1?Lipophilic marine biotoxins were widely distribute in coastal areas of Guangdong province,but the toxin contents in samples were generally lowered the sea food safe threshold.Eight lipophilic marine biotoxins profiles were detected,which were Homo-YTX,DTX1,DTX2,OA,GYM,SPX1,AZA2 and PTX2,respectively.2?Lipophilic marine biotoxins were seasonal in the detection rate.Detection rate of OA was high in autumn and low in winter,but no different was found in spring and summer.There was no seasonal distribution difference of AZA2 in the samples.Moreover,both the detection rate and the toxin content of AZA2 in samples were very low.No seasonal difference was also found in GYM and the detection rate of this toxin was up to 54.55%.SPX1 was only detected in C.rivularis collected from Zhapo in November 2014 and from Shanwei in May 2015,respectively.Detection rate of homo YTX and PTX2 were both high from the spring of 2014 to the spring of 2015,and the detection rate of PTX2 in spring was significantly higher than the other seasons.3?As to geographical distribution,OA pollution were detected along all the coastal areas of Guangdong Province,which was much more serious in east than in central and west Guangdong.GYM pollution were also detected along all the coastal areas of Guangdong but the most serious polluted area was in central coast of Guangdong.AZA2 pollution was only found in the eastern region.Shanwei and Yangjiang Zhapo were polluted by SPX1.Except Shenzhen Dapeng cove,homo YTX was detected in all the coastal areas of Guangdong,and the pollution level was much more serious in east coastal regions.4?Lipophilic marine biotoxins contents were also varied in different shellfish species.Mimachlamys nobilis had a high ability to accumulate OA.AZA2 was mainly detected in M.nobilis,Paphia undulate,Perna viridis,Lithophaga curta and C.rivularis.GYM was mainly detected in S.kagoshimensis,Pinctada fucata and C.angulata.M.nobilis and Cyclina sinensis were confirmed to be contaminated with homo YTX and PTX2,respectively.SPX1 was only detected in C.rivularis.5?In Dapeng cove,8 lipophilic marine biotoxins profiles were detected out,which were OA,DTX1,DTX2,GYM,PTX2,PTX2 sa,DA and homo-YTX,respectively.It was found that the detection rate of OA in C.angulata was high in autumn 2013 and summer 2014.GYM distributed widespread in the four seasons and the detection rate of GYM in C.angulata was high in winter.PTXs was high in autumn.In water samples,OA was only detected from January to March 2014.However,in water samples,GYM with a high content in winter,PTXs and DA with a high content in autumn were detected in each seasons.Homo-YTX in water sample was only detected in July,September 2013 and February 2014.This study revealed that there were varied lipophilic marine biotoxins in Guangdong coastal areas and some of the marine shellfish have been contaminated.For the food safety of marine shellfish,it is important for the relevant departments to draw and implement the monitoring and management programs of shellfish toxins.