State Key Laboratory of Water Simulation, School of Environment, Beijing Normal University, Beijing 100875, China.
State Key Laboratory of Water Simulation, School of Environment, Beijing Normal University, Beijing 100875, China.
Ecotoxicol Environ Saf. 2019 Jun 15;174:459-466. doi: 10.1016/j.ecoenv.2019.03.002. Epub 2019 Mar 7.
Current researches found some terrestrial animals absorb petroleum hydrocarbons (PHCs) in oil-polluted soil. However, the absorption behaviour between various biological tissues remains unclear. The aim of our study is to determine the toxic effects and enrichment behaviours of earthworms (Eisenia fetida) in petroleum-contaminated soils and to provide a reasonable dynamics model to explain the migration of PHCs within earthworm tissues. The PHCs are divided into three fractions by equivalent carbon number. An experimental analysis of the PHC concentrations in 3 different earthworm organ systems (body-wall tissue, body fluid and gut tissue) from a contamination exposure experiment at different time intervals was implemented. A dynamics model was built to simulate the absorption mechanism. The model results perform well. The PHC concentrations in the earthworm tissues were gut > body fluid > body wall. The PHCs in the gut reached equilibrium first, and those in the body-wall tissues reached equilibrium last. In the gut tissue, the PHC concentration was different from those in the body-wall tissue and body fluid due to the influence of the feeding rule. In addition, as the length of the carbon chain increases, the molecular size increases, which makes it more difficult for petroleum hydrocarbon fractions to enter an organ system. As a result, the concentration of PHCs in each type of tissue decreases with increasing carbon chain length. This study can provide a theoretical foundation for chemical monitoring in soil.
目前的研究发现，一些陆地动物会从受石油污染的土壤中吸收石油烃（PHC）。然而，各种生物组织之间的吸收行为尚不清楚。我们的研究旨在确定受污染土壤中蚯蚓（赤子爱胜蚓）对石油烃的毒性作用和富集行为，并提供一个合理的动力学模型来解释 PHC 在蚯蚓组织内的迁移。将 PHC 按等效碳数分为三个馏分。通过在不同时间间隔进行的污染暴露实验，对 3 种不同蚯蚓器官系统（体壁组织、体液和肠道组织）中 PHC 浓度进行了实验分析。建立了动力学模型来模拟吸收机制。模型结果表现良好。蚯蚓组织中的 PHC 浓度为肠道组织>体液>体壁组织。肠道组织中的 PHC 首先达到平衡，体壁组织中的 PHC 最后达到平衡。在肠道组织中，由于摄食规律的影响，PHC 浓度与体壁组织和体液中的浓度不同。此外，随着碳链长度的增加，分子尺寸增大，使得石油烃馏分更难进入器官系统。因此，每种组织中 PHC 的浓度随碳链长度的增加而降低。本研究可为土壤化学监测提供理论基础。
