日本虎斑猛水蚤的重金属急性毒性及其作为标准测试生物的潜在意义

Acute Toxicity of Heavy Metals to Tigriopus japonicus and Its Implication as a Standard Test Animal

以静态实验法研究重金属Cu、Cd、Pb和Zn单独以及两两联合对日本虎斑猛水蚤(Tigriopus japonicus)的急性毒性效应,并分析其是否适宜作为我国海水重金属毒性测试的标准生物。结果显示,单独作用下,Cu、Cd、Pb和Zn对受试生物的24h LC50分别为0.26、0.14、0.40和0.65mg·mL-1,海水中这4种重金属对该桡足类的安全浓度阈值分别为2.6、1.4、4.0和6.5μg.L-1。其中,Cu和Zn的安全浓度低于国家海水水质第一类标准,而Cd和Pb介于国家第一和第二类水质标准之间,这表明受试生物对这4种重金属的毒性十分敏感。而上述4种重金属两两联合对受试生物均为增强作用,说明重金属联合作用促使该桡足类动物的毒性敏感性增强。日本虎斑猛水蚤适宜作为我国海水重金属毒性测试的标准生物。

To determine whether Tigriopus japonicus is a proxy of standard test animal of heavy metals in marine water,the sensitivities of heavy metal Cu,Cd,Pb and Zn single and binary-combined acute toxicities to T.japonicus were studied by the static experiment.The results show that 24 h LC50 of single Cu,Cd,Pb and Zn to T.japonicus is 0.26,0.14,0.40 and 0.65 mg·L-1,respectively.The corresponding safety concentration of these four metals is 2.6,1.4,4.0 and 6.5 μg·L-1,respectively.Among which,the calculated safety concentration of Cu and Zn is less than the class level of China National Quality Standard for Sea Water,while it is between the class Ⅰ and class Ⅱ level for Pb and Cd,indicating that T.japonicus is sensitive to these four heavy metals.Moreover,enhancing interaction of toxic effects were shown under binary combinations of these four metals to T.japonicus,suggesting every two species of metals work together enhancing the toxic sensitivity of T.japonicus.This study demonstrates that T.japonicus should be an appropriate standard test animal of heavy metals in sea water.