State Key Laboratory of Marine Pollution, Department of Biomedical Sciences, City University of Hong Kong, Kowloon Tong, Hong Kong 999077, China.
Shenzhen Key Laboratory for the Sustainable Use of Marine Biodiversity, Research Centre for the Oceans and Human Health, City University of Hong Kong Shenzhen Research Institute, Shenzhen 518057, China.
Toxins (Basel). 2022 Mar 15;14(3):208. doi: 10.3390/toxins14030208.
Ciguatera is one of the most widespread food poisonings caused by the ingestion of fish contaminated by ciguatoxins (CTXs). Snapper and grouper with high palatable and economic value are the primary food source and fish species for exportation in the Republic of Kiribati, but they are highly suspected CTX-contaminated species due to their top predatory characteristics. In this study, 60 fish specimens from 17 species of snappers and groupers collected from the Kiritimati Island and Marakei Island of the Republic of Kiribati were analyzed using mouse neuroblastoma (N2a) assay and liquid chromatography-tandem mass spectrometry (LC-MS/MS) to determine Pacific CTX-1, -2 and -3 (P-CTX-1, -2 and -3). The LC-MS/MS results show that CTXs were detected in 74.5% of specimens from Marakei Island and 61.5% of specimens from Kiritimati Island. The most toxic fish from Marakei Island and from Kiritimati Island were detected as 53-fold and 28-fold P-CTX-1 equivalents higher than the safety level of 10 pg/g P-CTX-1 equivalents, respectively. CTX levels and composition profiles varied with species and location. The N2a results suggested that fish specimens also contain high levels of other CTX-like toxins or sodium channel activators. The distribution patterns for ciguatoxic fish of the two islands were similar, with fish sampled from the northwest being more toxic than the southwest. This study shows that groupers and snappers are high-risk species for ciguatera in the Republic of Kiribati, and these species can further be used as indicator species in ciguatera endemic areas for risk assessment.
雪卡毒素中毒是由食用受雪卡毒素（CTXs）污染的鱼类引起的最广泛的食物中毒之一。在基里巴斯共和国，红鲷鱼和石斑鱼因其美味可口且经济价值高，是主要的食物来源和出口鱼类，但由于它们处于顶级掠食者的地位，被高度怀疑是 CTX 污染物种。在这项研究中，从基里巴斯共和国的 Kiritimati 岛和 Marakei 岛采集了 17 种红鲷鱼和石斑鱼的 60 个鱼样本，使用小鼠神经母细胞瘤（N2a）测定法和液相色谱-串联质谱法（LC-MS/MS）来测定太平洋 CTX-1、-2 和 -3（P-CTX-1、-2 和 -3）。LC-MS/MS 结果表明，CTXs 在来自 Marakei 岛的 74.5%的样本和来自 Kiritimati 岛的 61.5%的样本中被检测到。来自 Marakei 岛和 Kiritimati 岛毒性最强的鱼类的 P-CTX-1 当量比安全水平（10 pg/g P-CTX-1 当量）分别高出 53 倍和 28 倍。CTX 水平和组成谱因物种和地点而异。N2a 结果表明，鱼样本还含有高水平的其他 CTX 类似毒素或钠通道激活剂。这两个岛屿的雪卡毒性鱼类分布模式相似，西北方向采集的鱼类毒性比西南方向的鱼类毒性更高。这项研究表明，石斑鱼和红鲷鱼是基里巴斯共和国雪卡毒素中毒的高风险物种，这些物种可以进一步用作雪卡毒素流行地区的指示物种，用于风险评估。
