Tetrodotoxin Poisoning 河鲀毒素中毒

广东疾控 · 公众号 · 养生 · 2017-04-10 21:37

正文

What is Tetrodotoxin?

Tetrodotoxin is a potent marine neurotoxin, named after the order Tetraodontiformes with which it is commonly associated. Puffer fish (see illustrations) and porcupine fish are common examples of fish containing tetrodotoxin under this order. Tetrodotoxin has also been isolated from other animal species including goby, shellfish, California newt, parrotfish, frogs of the genus Atelopus, the blue-ringed octopus, starfish, angelfish, and xanthid crabs.

什么是河鲀毒素？

河鲀毒素是一种毒性强烈的海洋生物神经毒素，因经常与魨形目的河鲀有关而得名。河鲀（见插图）和刺规是含河豚毒素的魨形目常见鱼类。此外，这种毒素亦会存在于鰕虎鱼、贝类海产、加州蝾螈、鹦哥鱼、斑蟾属蛙类、蓝纹章鱼、海星、神仙鱼和扁蟹等其他动物品种。

Illustrations:

Some species of poisonous puffer fish. Green rough-backed puffer (Lagocephalus lunaris) (top); yellow fin puffer (Takifugu xanthopterus) (bottom) (courtesy of Agriculture, Fisheries and Conservation Department)

插图：一些有毒的河鲀品种：月尾兔头魨(拉丁学名：Lagocephalus lunaris) (上)；黄鳍多纪魨(拉丁学名：Takifugu xanthopterus) (下) (由渔农自然护理署提供)

Tetrodotoxin is considered likely to be produced by marine bacteria that are often associated with marine animals. In puffer fish, the distribution of tetrodotoxin is mainly in the ovaries (eggs), liver and skin. The flesh is normally free of toxin. However, flesh of some toxic gobies such asYongeichthys nebulosis also contains tetrodotoxin.

Tetrodotoxin is heat-stable and therefore likely to remain in fish tissue after food preparation steps (e.g. cooking and drying). Eating fish containing tetrodotoxin such as puffer fish and porcupine fish can therefore be hazardous.

专家相信，河鲀毒素很可能是由经常与海洋生物有关的海洋细菌所产生。以河鲀来说，河鲀毒素主要分布在卵巢(鱼卵)、鱼肝和鱼皮，而鱼肉则通常不含毒素。不过，一些有毒的鰕虎鱼，例如云纹裸颊鰕虎鱼(拉丁学名：Yongeichthys nebulosis)，其鱼肉亦含有河鲀毒素。

河鲀毒素非常耐热，因此在烹煮和干燥等食物配制过程后多会仍然留在鱼组织内，所以吃河鲀和刺规等含有河鲀毒素的鱼类是十分危险的。

Toxicity of Tetrodotoxin

In human, the lethal dose of tetrodotoxin is around 1 to 2 mg and the minimum dose necessary to cause symptoms has been estimated to be 0.2 mg. The onset of symptoms of tetrodotoxin intoxication usually occurs from 10 to 45 minutes after ingestion, but may be delayed by three hours or more. Paraesthesia appears in the face and extremities, which may be followed by dizziness or numbness. Nausea, vomiting, diarrhoea and epigastric pain may also be present. Later, respiratory symptoms such as rapid breathing may follow. Low blood pressure, convulsions and irregular heart rate may occur. In most instances, the patients retain consciousness until shortly before death, which usually takes place within the first six hours. All humans are susceptible to tetrodotoxin poisoning. There are currently no known antidotes or antitoxins to tetrodotoxin. The treatment of symptoms is therefore supportive.

There are differences in toxicity and toxin distribution in tissues among different puffer fish species. In addition, seasonal, individual and local variations of toxicity and toxin composition in puffer fish are occasionally observed. Tetrodotoxin poisoning may be caused by ingestion of only a small amount of puffer fish.

河鲀毒素的毒性

人们摄入约１～２毫克河鲀毒素便可致命。另外，专家估计只需０.２毫克河鲀毒素便可令人出现中毒症状。河鲀毒素中毒症状通常会在病者吃下毒素后１０至４５分钟出现，但亦可延至三小时或以上。病者会觉得面部及手脚感觉异常，随后可能出现眩晕或麻痹，亦可能会有恶心、呕吐、腹泻和上腹疼痛。病者继而可能会有呼吸急速等呼吸症状，并可能出现低血压、抽搐和心律不正。一般而言，病者的神志会一直保持清醒，直至死亡前的一段短时间，而死亡通常在进食后的六小时内发生。所有人类均可受河鲀毒素中毒所影响。现时并无已知的解毒剂或抗毒素可消河鲀毒素，因此症状的疗法均属支持性质。

不同品种河鲀的毒性不同，毒素在组织的分布情况亦有异。此外，河鲀的毒性和毒素成分亦偶尔会因季节和水域的差异及每条鱼的独特性而不同。人们可能只吃了少量河鲀，便出现河鲀毒素中毒症状。