球肾白线蚓与赤子爱胜蚓生态毒理测试比较

Comparative study on ecological toxicology tests between Fridericia bulbosa and Eisenia foetida

通过对赤子爱胜蚓（Eisenia foetida）和球肾白线蚓（Fridericia bulbosa）的个体特征、饲养环境、试验方法操作性、受试生物的敏感性等方面开展系统比较,探讨了球肾白线蚓对土壤中典型污染物生态毒性检测的优势。结果表明,球肾白线蚓与赤子爱胜蚓相比,饲养、繁殖育种方法相似,但其个体特征差异明显、比表面积大;试验操作简便、易于观察、对环境产生的污染小;球肾白线蚓和赤子爱胜蚓的14 dLC50（暴露14 d后的半数致死浓度）可作为污染土壤风险评估的生物标志物,在选取同一污染物暴露的情况下,球肾白线蚓的14 d-LC50是赤子爱胜蚓的1/2001/5,对污染物的毒性效应更灵敏,可优先作为土壤污染风险评估的生物标志物。

This paper is aimed at reporting its study findings on the comparison of the ecological toxicology tests between Fridericia bulbosa and Eisenia foetida with the purpose to provide available methods and data supports for choosing suitable sensitive test species for the ecological risk assessment of the soil pollution in the country. For this purpose, we have conducted a 14-days＇ long artificial soil examination as a testing cycle. In proceeding with our investigation, we have prepared an artificial soil in accordance with OECD guideline 207 （ 1984 ）, including the following parts： a finely ground sphagnum peat in a dry weight ratio of 10%, 20% of kaolin clay, 70% of the industrial fine sand. And, then, the artificial soil is added by the calcium carbonate with pH value adjusted to 6. 5. Afterwards, F. bulbosa can be tested and made as a qualified potential species of the testing agent for the soil ecotoxicity assessment. And a step further is to compare F. bulbosa and E. foetida for their own individual features, rearing and breeding methods, the operability of the meth- ods and the sensitivity of the animal. Furthermore, we have made the exploration of the acute toxicity of the same pollutant on the mortality of F. bulbosa and E. fi）etida in the OECD soil. As a result, we have found that 14 d - LC50 for F. bulbosa in case to be exposed to chloroacetamide, PFOS, bromoxynil, Cd, phenanthrene, Hg, Cu should be 2. 01 mg/kg, 95.25 mg/kg, 0.48 mg/kg, 4. 55 mg/kg, 4.48 mg/kg, 0.73 mg/kg and 24.05 mg/kg, respectively, whereas 14 d - LC50 for E. foetida exposed to ehloroaeetamide, PFOS, bromoxynil, Cd, phenanthrene, Hg, Cu should be 13.53 mg/kg, 856. 82 mg/kg, 41.7,5 mg/kg, 788.71 mg/kg, 42. 51 mg/kg, 143.67 mg/kg and 109. 26 mg/kg, correspondingly. However, statistically significant difference can be found as to 14d -LC50 for F. bulbosa and E. foetida when exposed to the same pollutant （p 〈0. 05）. Thus, the results of our investigation and determination show that, though the rearing and breeding methods might be quite similar, the difference in the efficiency and effectiveness can still be great for the two different biological species, in ease the specific surface area of F. bulbosa is more large. Take F. bulbosa as a subject animal for example, the pollution to the environment is relatively small and the test operation is simple and easy to be noticed. On the other hand, the mortality rate （LC50） can be used as an effective biomarker for the toxicity assessment of the soil contamination. Under the same pollutant exposure situation, 14 d -LC50 for F. bulbosa may account for 1/200 - 1/5 of E. foetida. In comparison, F. bulbosa can be taken as more sensitive, and 14 d - LC50 for F. bulbosa can be used prima- rily as a biomarker to respond to the soil contamination. Thus, it can be concluded that F. bulbosa can be taken as a suitable test species for measuring the acute toxicity of the soil contamination.