| Considering the serious PSP(paralytic shellfish poisoning) pollution problem in Guangdong, the PSP profiles of the principle Bivalves samples in Guangdong coast have been analyzed by HPLC-FD and the difference and characteristics of PSP compositions in different Bays of Guangdong coast have been clarified in this paper. Meanwhile, three different projects have also been designed to monitor and manage the shellfish poison in Guangdong Coast.Based on the results of PSP distribution, the characteristic can be drawn as follows:First, regional differenceIt appears a big difference among the same kind of shellfish living in different geographical region at the same time. Take the Crassostrea giga for example, compared to the lower toxicity and less compositions in the middle zone of Guangdong coast, its toxicity are higher and its compositions are more in Opposite Guangdong coastal ends. Referring to Crassostrea rivularis, its toxicity is also different among the Bays. The most serious regions of PSP pollution are Jiazhi and Shenquan Harbor of Yuedong waters. Taiping and Houhai Bay are less serious. Meanwhile, the toxicity is about to none in Zhanjiang and Nanshui Bay.Second, seasonal differenceThe PSP toxicity of shellfish has large distinguish in different seasons. The PSP toxins can be detected in Crassostrea giga living in Zhelin Bay all the year, the main components of which are C1+C2, GTX1+GTX4,dcGTX2. The seasonal change of toxicity of Crassostrea giga is significant, which is the highest in spring of 2005, much lower in autumn and winter, yet comes to increasing significantly when next spring. In Daya Bay, the PSP toxicity in Crassostrea giga is rather lower all the year of 2005, and the main components are C1-2, dcGTX2-dcGTX3. The trend of seasonal change of toxicity in Daya Bay is similar with Zhelin Bay. PSP compositions of oyster are nearly the same in different seasons.Third, interspecific differenceThe ability of accumulating the PSP toxin of different kinds of shellfish is distinct among the seasons in the same region.(1) Taking the example of oyster, the higher toxicity and the more compositions are detected in Scapharca spp., Tegillarca granosa and Tegillarca nodifera than other oysters.(2) The special ability of accumulating PSP toxins is different among shellfishes. Some cockles such as egillarca nodifera and Scapharca anomalaa have strong accumulation ability to the GTX1, while Glaucomya chinensis accumulates to the GTX4.(3)Different cockles such as egillarca nodifera and Scapharca subcrenata have different toxin profiles, the former has high level GTX1, while the latter's toxicity is much lower and has wider toxin compositions.According to the analysis of the PSP compositions and the results of other investigators' research, as well as the reference to the successful experience of foreign biotoxin monitoring system, three different biotoxin monitoring and managing projects of Guangdong coast have been designed. The conclusion is: Daya Bay, Dapeng Bay and Zhelin Bay are designated as the principle monitoring zone. Shuidong Bay, Leizhou Bay, Liusha Bay, Shenquanjiazi Harbor, Nanao Bay and Chuanshan Islands are the second monitoring zone. Jieshi Bay, Honghai Bay, Dahao Bay, Hailin Bay, Anbu Harbor and Wanshan Islands are the general monitoring zone. The project of principle monitoring zone is: The toxic algae, Alexandrium tamarense, Alexandrium catanella, Gymnodinium catenatum and Total Dinophysis sp., are the main monitoring algae, which should be monitored fortnightly, and shellfishes, Crassostrea spp., Mytilus edulis, Chlamys nobili and Scapharca spp. are monitored weekly from January to October every year. The project will be carried out under the special conditions. The closure time of a shellfish harvesting area is depending either upon the high concentrations of toxic algae in the water or on the concentration, which excess specified threshold of toxins in the shellfish. The project of the second monitoring zone is: shellfish Crassostrea spp., Mytilus edulis, Chlamys nobili and Scapharca spp. are the main monitoring subjects, which should be monitored fortnightly from January to October. The closure time of a shellfish harvesting area is only depending on the concentration, which excess specified threshold of algal toxins in the shellfish. While in the general monitoring zone, one or more shellfishes Crassostrea spp., Mytilus edulis, Chlamys nobili and Scapharca spp are monitored fortnightly in important stations from January to May and July to October, when the PSP toxicity is over 20μg100g-1, the project should be changed into the second monitoring zone project.In addition, the management of biotoxin monitoring program, such as the functions of management institutions and so on,are also discussed in this paper. The results of this paper will provide important principle theories and practical monitoring models for the government, who is about to establish the biotoxin monitoring system in Guangdong. It also has a good help to insure the sustainable development of aquaculture industry and the safe of aquatic products.
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