藍藻毒素對底棲動物的毒理學研究進展

薛慶舉, 蘇小妹, 謝麗強

1 中國科學院南京地理與湖泊研究所湖泊與環(huán)境國家重點實驗室, 南京 210008 2 中國科學院大學, 北京 100049

藍藻毒素對底棲動物的毒理學研究進展

薛慶舉1,2, 蘇小妹1,2, 謝麗強1,*

1 中國科學院南京地理與湖泊研究所湖泊與環(huán)境國家重點實驗室, 南京 210008 2 中國科學院大學, 北京 100049

近年，由于人類活動加劇，大量氮磷等營養(yǎng)物質流入湖泊等緩流水體，導致水體富營養(yǎng)化。而由此引起有害藍藻水華的頻繁爆發(fā)，使生態(tài)環(huán)境和人類健康受到嚴重威脅。相關研究表明，藍藻水華的爆發(fā)不僅能夠使水體水質惡化，其中一些產(chǎn)毒藻類還會產(chǎn)生大量藍藻毒素，對水生生物產(chǎn)生重要影響。底棲動物作為水體生態(tài)系統(tǒng)的重要組成部分，在食物網(wǎng)中有重要作用，同時其中的許多種類又與人類息息相關，因此關于水華藍藻毒素對淡水底棲動物的毒理學研究具有重要意義。在介紹藍藻毒素概況的基礎上，綜述了藍藻毒素的致毒機理和對底棲動物的影響，展望了研究方向。

底棲動物; 藍藻毒素; 食物網(wǎng); 環(huán)境毒理學

由于人類活動的加劇，氮磷等植物營養(yǎng)物質大量流入水體，造成水體富營養(yǎng)化，在與光照、溫度、濁度、pH值、電導率、鹽度和一些水文條件(如水體的流動性)等相互影響后[1]，最終使一些光能自養(yǎng)型藻類大量繁殖而導致藻類水華爆發(fā)。淡水水體水華的發(fā)生主要以藍藻水華為主，藍藻的大量繁殖不但會對水體造成直接影響(如溶解氧降低等)，還能夠產(chǎn)生毒性很強的代謝產(chǎn)物——藍藻毒素(cyanotoxin)，危及動物和人類安全。

底棲動物是水體中與藍藻毒素具有最直接關系的一類水生生物。底棲動物是指生活史的全部或大部分時間生活于水體底部的水生動物類群，是水生態(tài)系統(tǒng)的一個重要組成部分[2]。底棲動物在水生態(tài)系統(tǒng)中發(fā)揮著重要作用。首先，它們可以加速水底物質分解，促進水體自凈；其次，底棲動物是水體生態(tài)系統(tǒng)食物鏈的重要組成部分，不僅是浮游生物的捕食者，還是一些掠食動物(Predators)的食物，有的雜食種類還能充當分解者；再次，底棲動物在水體富營養(yǎng)化研究中有重要作用，它們可以通過自身的生命活動對水體中營養(yǎng)鹽的含量產(chǎn)生重要影響，其中的一些物種已經(jīng)被用于水體富營養(yǎng)化的治理。同時，底棲動物中有許多物種不僅是一些水產(chǎn)品的重要餌料，還是倍受人類歡迎的美食。所以，研究藍藻毒素對底棲動物的毒理學具有重要的理論和實際意義。有鑒于此，本文綜述了藍藻毒素對底棲動物的毒理學研究現(xiàn)狀，對藍藻毒素的基本性質、致毒機理、在生物體內的累積與清除，以及對底棲動物的影響進行了綜述，并進一步對未來研究重點進行了展望，以期能夠為今后對藍藻毒素的進一步研究提供參考。

1 藍藻毒素概述

自1878年首次報道藍藻毒素導致家禽死亡后，世界范圍內關于藍藻毒素對動物和人類危害的報道越來越多，當家畜及野生動物飲用含有藻毒素的水之后，一般會出現(xiàn)肝臟腫大、充血或壞死，腸炎出血、肺水腫等病變，同時因接觸藍藻毒素而導致的人類死亡事件也時有發(fā)生，而有學者亦指出中國南方原發(fā)性肝癌的高發(fā)病率與飲用水中含有微囊藻毒素(Microcystin， MC)存在一定的關系[3-6]。相關研究發(fā)現(xiàn)，藍藻毒素為藍藻的次級代謝產(chǎn)物，在不同生境都有廣泛的分布[7]。藍藻毒素根據(jù)化學結構可以分為三類：環(huán)肽(Cyclic peptide)、生物堿(Alkaloid)和脂多糖內毒素(Lipopolysacchride, LPS)；也可根據(jù)毒素作用位置的不同分為肝毒素(Hepatotoxin)、神經(jīng)毒素(neurotoxin)、細胞毒素(cytotoxin)和皮膚毒素(dermatotoxin)等[8]。而其中微囊藻毒素(MC)是世界各地最為常見且危害最嚴重的毒素，具有顯著的肝臟毒性，其結構在20世紀80年代初得到確認，為環(huán)狀七肽結構，目前已發(fā)現(xiàn)80余種毒素亞型，最常見的為MC-LR，在世界范圍內得到最廣泛的關注[9-11]。除MC之外，對其它毒素(如節(jié)球藻毒素(Nodularin)、擬柱孢藻毒素(Cylindrospermopsin，CYN)和生物堿毒素等)的研究相對較少。

相關研究發(fā)現(xiàn)，MC的性質穩(wěn)定，大多數(shù)MC是親水的，一般在水中的溶解度能達到1 gL以上，不易沉淀或被沉積物和懸浮顆粒物吸附，易溶于甲醇或丙酮。由于MC分子結構中含有羧基、氨基和酰氨基，所以在不同pH值條件下MC有不同的離子化傾向[12],但蛋白質水解酶對它們卻不起作用。MC還具有熱穩(wěn)定性，在加熱到300 ℃后仍能維持很長時間不分解[1]。MC在陽光照射下亦非常穩(wěn)定，但是在不同濃度的水可提取色素存在的條件下它的穩(wěn)定性和異構化有顯著的變化[8]，同時在某些條件下MC能夠被生物所降解。

2 致毒機理

圖1 動物細胞中微囊藻毒素MC的攝取、毒性機制、生物轉化和排泄的路徑[14]

由于MC具有親水性導致其不能以被動運輸?shù)姆绞酵ㄟ^細胞膜，而只能依靠相應載體的運輸，這也是MC器官選擇性毒性的重要原因[13]，MC在動物細胞中的遷移轉化過程如圖1[14]所示。MC致毒的分子機制主要有以下幾個方面：抑制蛋白磷酸酶的活性、引起氧化應激和內質網(wǎng)應激。研究發(fā)現(xiàn)微囊藻毒素和節(jié)球藻毒素可以與蛋白磷酸酶(protein phosphatases, PPs)1和2A的絲氨酸蘇氨酸亞基相結合，從而抑制它們的活性[15-17]。由于蛋白磷酸酶在催化蛋白分子脫磷酸化和調控細胞骨架與細胞凋亡等過程中具有重要的作用，所以當?shù)鞍琢姿崦窹P1和PP2A被抑制時，會導致細胞過度磷酸化，甚至使細胞凋亡[18]。同時，蛋白磷酸酶的抑制可使DNA依賴的蛋白激酶(DNA-dependent Protein Kinase, DNA-PK)失活，進而造成DNA的損傷[19-20]。MC還能夠引起活性氧簇(Reactive oxygen species, ROS)的快速產(chǎn)生，而ROS的大量產(chǎn)生會導致脂質過氧化、線粒體結構和功能的破壞和DNA損傷等。而MC對細胞內抗氧化系統(tǒng)的損傷主要是在與OATP(Organic anion transporting polypeptides，有機陰離子轉運多肽)載體結合進入細胞時谷胱甘肽(Glutathione，GSH)的流出導致的[10,21-23]。目前對于內質網(wǎng)應激的研究還相當少，但已有研究表明，MC可能導致錯誤折疊的蛋白質在內質網(wǎng)內堆積，從而引起內質網(wǎng)應激[24]。隨著不斷的研究發(fā)現(xiàn)，MC的毒性作用在最后幾乎都能導致細胞的凋亡，同時還有一定的促癌作用，而對于藍藻毒素在生物體內的轉化還需要進一步深入的研究。

3 藍藻毒素與底棲動物

藍藻毒素對淡水水生生物作用的研究較少且大多集中于一些魚類和某些大型的底棲動物，原因可能主要有以下幾個方面：一方面，與海洋藻毒素相比，淡水藻毒素對人類和一些動物產(chǎn)生的急性中毒事件較少；第二，人類對淡水水產(chǎn)品的消耗量與海洋水產(chǎn)品的消耗量相比要小的多，聯(lián)合國食品與農(nóng)業(yè)組織調查發(fā)現(xiàn)，2008年全球捕魚量為9000萬 t，而內陸淡水捕魚量只有1000萬 t[25]；第三，所研究的淡水水生生物大都是被人類食用的食物(如螺、蚌和蝦等)，對人類可能存在較大的潛在危害；同時，研究還會受生物個體特征、實驗和檢測分析條件的限制，如生物食性、生物量大小、存活能力和體內毒素含量。目前的研究基本集中在生物體內或者不同器官中藻毒素富集和清除的研究，也有一些藻毒素在同一生物不同器官中分布和對不同成長階段個體影響的研究，但對于藻毒素在生物體內的分子生物學轉化及代謝和生物鏈中轉移機制方面的研究則相對較少。

3.1 藍藻毒素在底棲動物體內的富集與清除

底棲動物通過不同的方式富集MC后，MC大部分富集于消化道、肝胰腺和性腺三個器官之內，以消化道和肝胰腺中的含量最高，多數(shù)研究結果都已超過WHO的規(guī)定(0.04 μg kg-1d-1)[26]，關于藍藻毒素在底棲動物體內的富集與清除詳見表1。相對來說，底棲動物的足和肌肉中MC的含量要小的多，所以在只食一些底棲動物的足或者肌肉的情況下，MC對于人類健康的影響相對較小[27-36]。研究表明，MC在底棲動物體內的富集與一些環(huán)境因子存在一定的相關性。如Ozawa[29]等研究淡水田螺(Sinotaiahistrica)肝胰腺和腸道中MC的季節(jié)變化時發(fā)現(xiàn)，當湖泊中浮游植物體內MC含量最高時(10月)，田螺腸道和肝胰腺中的MC的含量也最高，而Yokoyama和Park[37]發(fā)現(xiàn)褶紋冠蚌(Cristariaplicata)在夏季水華時MC含量很低，但是在水華消失的秋季卻迅速升高；Chen和Xie[31]對3種雙殼類的研究得出，夏季大部分器官MC含量的峰值與懸浮顆粒物和水華藍藻的MC含量峰值相吻合，同時，Chen和Xie[33]還指出不同底棲動物中不同的MC含量可能與攝取的食物不同有關。Lance[38]等和Prepas[39]等的研究表明，靜水椎實螺(Lymnaeastagnalis)和淡水無齒蚌 (Anodontagrandissimpsoniana)對MC的富集主要通過攝食含有毒素的浮游植物，而極少通過吸收溶解的毒素，而Zhang[40]等對橢圓蘿卜螺(Radixswinhoei)和螺獅(Margaryamelanioide)各器官對MC的生物富集的研究卻發(fā)現(xiàn)，橢圓蘿卜螺中MC濃度與環(huán)境中的溶解MC有關，而螺獅中的MC濃度與細胞內毒素相關。Zhang[30]等對太湖中銅銹環(huán)棱螺(Bellamyaaeruginosa)的研究還發(fā)現(xiàn)，后代體內MC含量還與母體性腺中MC的含量有關。Zhang[9]等對太湖銅銹環(huán)棱螺肝胰腺中3種最常見的毒素亞型(MC-LR、MC-RR和MC-YR)的時空分布的研究指出，MC在肝胰腺中濃度的變化與不同點位水體中細胞內毒素的變化一致，且與懸浮顆粒物中MC濃度顯著相關，同時結果表明其它因素(如水溫)對銅銹環(huán)棱螺肝胰腺內的MC富集有重要的影響；當?shù)讞珓游锾幱诓煌臓I養(yǎng)級時，其體內MC的含量也會有很大的差別[35]。Galanti[42]等在室內對淡水蝦Palaemonetesargentinus的研究發(fā)現(xiàn)，將P.argentinus在MC-LR(50 μg/L)中培養(yǎng)3 d后就能檢測到MC，同時還指出MC與GSH的結合是P.argentinus的一種重要的MC解毒機制。

目前對擬柱孢藻毒素(CYN)等其它毒素生物富集的研究相對較少。Seifert[43]的研究顯示CYN在低于100 μg/L情況下就能對一些水生無脊椎動物產(chǎn)生顯著的影響。Saker和Eaglesham[44]第一次對紅螯螯蝦(Cheraxquadricarinatus)肌肉和肝胰臟中CYN的濃度進行了檢測，發(fā)現(xiàn)肝胰腺和肌肉組織中含量分別達到4.3和0.9 mg/kg(干重)，而室內研究結果要比野外低很多。Saker[45]等將淡水無齒蚌(Anodontacygnea)暴露于不同濃度的CYN中，發(fā)現(xiàn)各器官中所占比例為血淋巴68.1%，內臟為23.3%，足和性腺為7.7%，外套膜0.9%，在鰓和肌肉中未發(fā)現(xiàn)，而且在經(jīng)過14 d的清除之后還有大約50%的毒素存留。White[46]等在實驗室內對瘤擬黑螺(Melanoidestuberculata)的研究發(fā)現(xiàn)腹足類亦有富集CYN的能力。而Berry和Lind[47]對一腹足類(Pomaceapatulacatemacensis)的野外研究發(fā)現(xiàn)，組織中毒素含量為(3.35±1.90)ng/g，但是生物富集系數(shù)卻為157，說明CYN濃度非常低時也會發(fā)生生物富集。Wood[48]等對淡水小龍蝦(Paranephropsplanifrons)的研究發(fā)現(xiàn)，其肝胰腺中nodularin-R濃度(9.7—225.3 μg/kg, 濕重)顯著高于尾部組織的濃度(0.5—0.7 μg/kg, 濕重)。Galanti[42]等將P.argentinus放入含有節(jié)球藻毒素的水庫后發(fā)現(xiàn)，3周后P.argentinus中也能檢測到節(jié)球藻毒素。Kankaanp??[49]等發(fā)現(xiàn)節(jié)球藻毒素在海產(chǎn)貽貝、斑紋蚌(Dreissenapolymorpha)和波羅的海白櫻蛤(Dreissenapolymorpha)中都有富集現(xiàn)象。除以上幾種毒素的研究外，還有少量對其它毒素在底棲生物中富集與清除的研究[50-51]。

表1 藍藻毒素在底棲動物體內的富集與清除

3.2 藍藻毒素對底棲動物的毒理作用

藍藻毒素對底棲動物的毒性作用主要有急性毒性，如存活個體的減少、攝食的抑制和麻痹等；慢性毒性，如對生長和繁殖的影響；生物化學的變化，如磷酸酶、谷胱甘肽S轉移酶和蛋白酶等活性的改變等；還有就是對動物行為的影響[52]。

MC對腹足類生活史特征的影響因生物年齡、暴露方式(產(chǎn)毒藻類或者溶解性MC)和是否存在無毒食物的不同而不同，實驗研究發(fā)現(xiàn)MC能夠導致胚胎發(fā)育變緩，孵化成功率和后代存活率降低[53]。Zhu[54]等用兩種暴露方式(單一有毒藍藻和有毒藍藻與無毒綠藻混合)對銅銹環(huán)棱螺進行處理，然后觀察螺肝胰腺超微結構和生物化學反應的變化，發(fā)現(xiàn)在中毒階段后期肝中酸性磷酸酶、堿性磷酸酶和谷胱甘肽S轉移酶活性顯著升高，而在清除階段酶的活性又回到原來水平，同時出現(xiàn)細胞質嚴重液泡化、細胞核壓縮變形、線粒體膨脹成髓狀、內質網(wǎng)粗面被破壞和溶酶體增殖等現(xiàn)象，并觀察到細胞凋亡，放到無毒藻類處理中這些現(xiàn)象便消失，這些反應可能是細胞用來減少傷害的適應機制。這與Martins[55]等對MC與底棲動物相互作用所表現(xiàn)出得生物化學反應的研究結果相似。Puerto[56]等對擬柱孢藻毒素對兩種雙殼類細胞內生物化學反應的影響進行了研究。毒素對生物的胚胎發(fā)育也有負面的影響，而且能夠從受污染的母體性腺中傳遞到后代體內[33,57]。Lance[58]等對淡水螺(Potamopyrgusantipodarum)的研究就發(fā)現(xiàn)，MC不僅能夠影響螺的生存和生長，而且對它的繁殖也產(chǎn)生了一定影響。MC對不同底棲動物的群落結構也會產(chǎn)生顯著的影響，Lance[53]等發(fā)現(xiàn)腹足類前鰓亞綱和肺螺亞綱種群對MC有不同的反應，而肺螺亞綱對MC的抗性更強；Gérard[59]等的研究指出在受MC嚴重污染的水體中軟體動物豐度和物種豐富度沒有顯著變化，而肺螺亞綱、前鰓亞綱和雙殼綱的相對多度在藍藻水華前后卻又顯著的不同。Lance[60]等對靜水椎實螺(Lymnaeastagnalis)的研究發(fā)現(xiàn)，MC使螺的生長變緩，這在幼年個體中更為顯著，而成年個體的繁殖能力降低，沒有發(fā)現(xiàn)存活率和遷移的變化，同時螺體內消化腺發(fā)生了一些可逆的變化，在未進食有毒藻類3周后變化消失。Gérard[61]等發(fā)現(xiàn)有毒藍藻的循環(huán)性增殖與腹足類群落生物的減少相吻合。Oberholster[62]等發(fā)現(xiàn)水體中微囊藻毒性的增加伴隨著大型無脊椎動物中蛭綱、搖蚊科和顫蚓科豐度的增加，在遠離藍藻浮渣的地方大型無脊椎動物豐度較低但多樣性卻較高，這可能與較細無機顆粒對生境多樣性的改變、腐殖質分解使可利用溶氧降低、大量懸浮顆粒物長時間存在使透光性降低、藻類浮渣釋放毒素對大型無脊椎動物的毒性作用和浮渣對pH與營養(yǎng)鹽濃度等指標的影響有關。

3.3 底棲動物對藍藻毒素在食物網(wǎng)中的傳播作用

相關研究得出，MC能夠在食物鏈中遷移，但沒有生物放大現(xiàn)象[63]。Papadimitriou[64]等對食物網(wǎng)中不同組成部分中MC的分布和累積進行了研究，雖然沒發(fā)現(xiàn)生物放大的證據(jù)，但是MC對動物和人類健康的威脅仍然存在。Kozlowsky-Suzuki[65]等研究了食物網(wǎng)中MC消費者浮游動物、十足目、軟體動物、魚類、烏龜和水鳥體內MC的濃度，結果表明大部分的初級消費者表現(xiàn)為生物稀釋，研究中僅有浮游動物和以浮游動物為食的魚類出現(xiàn)生物放大現(xiàn)象，這與Ibelings[66]等的研究一致。基于對簡單食物鏈模型(Microcystisaeruginosa→Daphniapulex→Chaoborus)的研究，Laurén[67]等發(fā)現(xiàn)捕食含有毒微囊藻飼養(yǎng)水蚤的幽蚊死亡率更高。雖然生物鏈幾乎不能累積MC，但是MC卻能夠以底棲動物假糞的形式被魚類攝取而進入食物鏈[68]。Poste 和Ozersky[69]也發(fā)現(xiàn)貽貝可以通過兩種方式將MC傳遞到更高的營養(yǎng)級，一是被底棲魚類(如蝦虎魚)所捕食，再就是可以通過它們的生物沉積物間接被其它底棲無脊椎動物取食。同時，Lance[70]等通過喂食魚類靜水椎實螺消化腺發(fā)現(xiàn)，魚類的各個器官都會檢測到MC，且含量按肝臟、肌肉、腎臟和鰓的順序降低。

4 討論

由于底棲動物為水體中有毒物質的最直接接觸者，目前關于底棲動物毒理學的研究已成為水環(huán)境毒理學研究的一個熱點，經(jīng)過多年的發(fā)展，已經(jīng)獲得了很多重要成果，但關于水華藍藻毒素對底棲動物的毒理學研究仍然存在許多的問題需要進一步的研究，而今后最值得關注的問題主要有以下幾個方面：

(1)毒素分析方法等的標準化 在對毒素近幾十年的研究中，發(fā)展了許多檢測分析毒素的方法，但由于毒素種類和異構體繁多、水體其它有毒物質干擾和檢測儀器設備等問題，使得各種方法在實際的應用中存在一定的局限性，從而導致目前國際上還沒有檢測毒素的標準方法。同時，由于人類接觸的毒素為各種毒素的混合，而目前對人體每天攝入量的規(guī)定只限于單一的毒素種類，對水產(chǎn)品的中含量的限定亦沒有標準，所以對毒素監(jiān)測分析方法和攝入量標準的研究仍會是今后研究的重要方向。

(2)加強藍藻毒素對底棲動物致毒的分子機理和急性與慢性中毒反應，以及不同毒素之間的協(xié)同關系的研究 在重點研究微囊藻毒素的同時，還應加大對其他種類毒素的研究。同時，還應對藍藻毒素進行長期的觀測，進一步研究藍藻毒素在底棲動物體內富集、轉化、代謝以及沿食物鏈的傳遞機制，并篩選藻毒素污染指示生物，從而為進一步監(jiān)測和評價其對人類健康的威脅提供證據(jù)。

(3)底棲動物對藍藻毒素清除機制的研究 目前，相關研究已經(jīng)證明底棲動物中的一些貝類對藍藻毒素有很高的富集與清除能力，而貝類具有生物量大、濾食能力強、易于存活等特點，重要的是其中一些貝類具有很高的抗毒能力，所以對底棲動物清除藍藻毒素機制的研究，對有毒藍藻水華的防范與控制具有重要的意義。

(4)進一步加強對水體富營養(yǎng)化的研究 藍藻毒素都是由藻類所產(chǎn)生，所以控制藍藻毒素的關鍵最后還要依靠對水體富營養(yǎng)化的治理，既淡水水體水華各方面的研究仍是今后的熱點。

(5)加強對一些最新研究方向的研究 主要有兩個方面，一方面是關于一些藥物對藍藻毒素毒性作用的緩解作用的研究，如已有研究表明抗生素利福平、免疫抑制劑環(huán)孢霉素A[71]和抗氧化劑維生素E[72]對MC的生物毒性都有一定的緩解作用；二是對藍藻毒素的利用，有研究發(fā)現(xiàn)微囊藻毒素能夠促使肝癌細胞凋亡[73]，這表明一些藻毒素有可能成為重要的抗癌藥物，所以關于這方面的研究必將成為一個新的熱點。

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Advances on cyanotoxin toxicology of zoobenthos

XUE Qingju1,2, SU Xiaomei1,2, XIE Liqiang1,*

1StateKeyLaboratoryofLakeScienceandEnvironment,NanjingInstituteofGeographyandLimnology,ChineseAcademyofSciences,Nanjing210008,China2UniversityofChineseAcademyofSciences,Beijing100049,China

In recent years, owing to the intensified human activities, a large number of nutrients, primarily nitrogen and phosphorus, flow into lakes and other water bodies and result in serious eutrophication. However, the cultural eutrophication is often associated with cyanobacteria blooms which can create significant water quality and human health problems. What′s more, some species of cyanobacteria are capable of producing secondary metabolites named cyanotoxins. Mass populations of toxin-producing cyanobacteria are in natural and controlled water bodies include blooms and scums of planktonic species, and mats and biofilms of benthic species. Toxic cyanobacterial populations have been reported in freshwaters in over 45 countries. These toxins can be classified into five main types according to their mechanism of action in vertebrates: hepatotoxins, cytotoxins, dermatotoxins, neurotoxins and irritant toxins. These toxins (microcystins, nodularins, saxitoxins, anatoxin-a, anatoxin-a(s), cylindrospermopsin) are structurally diverse and their effects range from liver damage, including liver cancer, to neurotoxicity. There are more than 80 microcystin congeners, microcystin-LR (L, L-leucine; R, L-arginine) is the best studied cyanobacterial toxin, whereas information for the other toxins is largely lacking. Many studies on the effects of cyanobacteria and their toxins over a wide range of aquatic organisms, including invertebrates and vertebrates, have reported acute effects (e.g., reduction in survivorship, feeding inhibition, paralysis), chronic effects (e.g., reduction in growth and fecundity), biochemical alterations (e.g., activity of phosphatases, GST, AChE, proteases), and behavioral alterations. Research has also focused on the potential for bioaccumulation and transferring of these toxins through the food chain. In general, the toxins can transfer to human bodies by drinking and very little by entertainment or health care products. In some special circumstances, the toxins can also be transferred into human bodies by dialysis. Be the highest level of the food chain, toxins can also transfer to human beings by eating aquatic products. As an important part of the aquatic ecosystem, zoobenthos plays an important role in the aquatic food web. On the one hand, it plays an important part in the material and energy flow process. It is not only the source of the predacity fish, but also the predator of the phytoplankton, zooplankton or organic detritus. On the other hand, some species of the zoobenthos can also be used in water cleaning and influence the formation of the eutrophication. The most important thing is that many of them are even closely related to human beings (directly or indirectly food sources), especially the people leave around the lakes and other water bodies, so the study of the cyanotoxin toxicology of zoobenthos is of great importance. In this review, we first summarized the mechanism of toxicity of cyanotoxin on zoobenthos on the base of a brief introduction of cyanotoxins, with emphasis on microcystins. Secondly, the effects of cyanotoxins on zoobenthos is discussed in details, including the bioaccumulation and elimination of the cyanotoxin, the effects of cyanotoxin and the food web studies about cyanotoxin (mainly microcystis) in zoobenthos. At last, we prospect the further research directions as well as drawbacks and future needs in this field of research.

zoobenthos; cyanotoxin; food web; environmental toxicology

中國科學院百人計劃(y3bro11050); 南京地理與湖泊研究所一三五項目(NIGLAS2012135015)

2013-08-26;

2014-10-09

10.5846/stxb201308262157

*通訊作者Corresponding author.E-mail: lqxie@niglas.ac.cn

薛慶舉, 蘇小妹, 謝麗強.藍藻毒素對底棲動物的毒理學研究進展.生態(tài)學報,2015,35(14):4570-4578.

Xue Q J, Su X M, Xie L Q.Advances on cyanotoxin toxicology of zoobenthos.Acta Ecologica Sinica,2015,35(14):4570-4578.