Ojeong Eco-Resilience Institute, Korea University, Seoul, 02841, Republic of Korea.
Department of Environmental Science and Ecological Engineering, Korea University, Seoul, 02841, Republic of Korea.
Environ Sci Pollut Res Int. 2019 Sep;26(25):26184-26192. doi: 10.1007/s11356-019-05892-7. Epub 2019 Jul 6.
In the standard ISO soil toxicity test using Collembola, adult survival and juvenile production are the only endpoints that can be attainable. The information on egg production and egg hatching cannot be investigated in the ISO test. To overcome this limitation, in this study, the effects of teflubenzuron on life history parameters of Yuukianura szeptyckii (Collembola) were investigated with a compressed soil test. Teflubenzuron is an insect growth regulator and has a negative effect on egg production, and egg hatching process of arthropods. LC decreased with increases in exposure period from 6.97 mg/kg in the third week to 3.60 mg/kg in the fourth week. The EC for egg and juvenile production was 0.57 mg/kg and 0.26 mg/kg, respectively. The hatching rate decreased significantly from 46 to 7% as the concentration increased from 0.25 to 1.00 mg/kg, respectively, and the molting frequency was significantly affected only at > 4 mg/kg. The toxic contribution rate (TCR) was defined as the ratio of juvenile production at an exposure concentration compared with the control, and a simple life history model was developed for TCR estimations. At the lower concentrations (< 0.3 mg/kg), the hatching rate reduction was a main contributor to the total toxicity, but the adult mortality and egg production reduction were the main contributors at the higher concentrations (> 2.0 mg/kg). The contribution of egg production reduction remained relatively constant. Since collembolan populations in the soil can be composed of various developmental stages, the differences in the sensitivity to chemicals depending on the developmental stages should be included in the assessment of the toxic impact on soil ecosystems.
在使用弹尾目昆虫进行的标准 ISO 土壤毒性测试中，只有成虫存活率和幼体产量这两个终点是可达到的。ISO 测试无法调查产卵和卵孵化信息。为了克服这一限制，本研究采用压缩土壤测试，调查了氟虫脲对栉角跳虫（弹尾目）生活史参数的影响。氟虫脲是一种昆虫生长调节剂，对节肢动物的产卵和卵孵化过程有负面影响。LC 随暴露期的增加而降低，从第三周的 6.97mg/kg 降至第四周的 3.60mg/kg。卵和幼体产量的 EC 分别为 0.57mg/kg 和 0.26mg/kg。随着浓度从 0.25mg/kg 增加到 1.00mg/kg，孵化率分别显著从 46%下降到 7%，蜕皮频率仅在 >4mg/kg 时受到显著影响。毒性贡献率（TCR）定义为暴露浓度下的幼体产量与对照相比的比值，并为 TCR 估计开发了一个简单的生活史模型。在较低浓度（<0.3mg/kg）下，孵化率降低是总毒性的主要贡献因素，但在较高浓度（>2.0mg/kg）下，成虫死亡率和产卵量减少是主要贡献因素。产卵量减少的贡献相对保持不变。由于土壤中的弹尾目种群可能由不同的发育阶段组成，因此应在评估对土壤生态系统的毒性影响时，考虑到不同发育阶段对化学物质敏感性的差异。
