Maner Jenny, Burkard Michael, Cassano Juan Carlos, Nash Susan M Bengtson, Schirmer Kristin, Suter Marc J-F
Department Environmental Toxicology, Eawag, Swiss Federal Institute of Aquatic Science and Technology 8600 Dübendorf Switzerland
Department of Environmental Systems Science, ETH Zürich 8092 Zürich Switzerland.
RSC Adv. 2019 Nov 29;9(67):39447-39457. doi: 10.1039/c9ra05352b. eCollection 2019 Nov 27.
Humpback whales, like other polar wildlife, accumulate persistent organic pollutants. In Southern hemisphere populations, hexachlorobenzene (HCB) dominates the contaminant profiles. HCB is linked to a variety of health effects and is classified as a group 2B carcinogen, but the mechanism of action is a matter of contention. Potential toxicological effects to humpback whales remain entirely unknown. The recently established humpback whale fibroblast cell line (HuWa) offers an model for toxicological investigations. We here combine this novel cell line with a passive dosing strategy to investigate whale-specific toxicity of HCB. The relevant partitioning coefficients were determined to produce stable and predictable exposure concentrations in small-scale bioassays. The system was used to assess acute toxicity as well as genotoxicity of HCB to the HuWa cell line. While we found some transient reductions in metabolic activity, measured with the indicator dye alamarBlue, no clear acute toxic effects were discernible. Yet, a significant increase in DNA damage, detected in the alkaline comet assay, was found in HuWa cells exposed to 10 μg L HCB during the sensitive phase of cell attachment. Collectively, this work provides a ready-to-use passive dosing system and delivers evidence that HCB elicits genotoxicity in humpback whale cells.
座头鲸与其他极地野生动物一样，会积累持久性有机污染物。在南半球的种群中，六氯苯（HCB）在污染物谱中占主导地位。六氯苯与多种健康影响有关，被归类为2B类致癌物，但其作用机制仍存在争议。对座头鲸潜在的毒理学影响仍然完全未知。最近建立的座头鲸成纤维细胞系（HuWa）为毒理学研究提供了一个模型。我们在此将这种新型细胞系与被动给药策略相结合，以研究六氯苯对鲸鱼的特异性毒性。测定了相关的分配系数，以便在小规模生物测定中产生稳定且可预测的暴露浓度。该系统用于评估六氯苯对HuWa细胞系的急性毒性以及遗传毒性。虽然我们发现用指示染料alamarBlue测量的代谢活性有一些短暂下降，但没有明显的急性毒性作用。然而，在细胞附着的敏感阶段，暴露于10μg/L六氯苯的HuWa细胞中，碱性彗星试验检测到DNA损伤显著增加。总的来说，这项工作提供了一个现成的被动给药系统，并证明六氯苯会在座头鲸细胞中引发遗传毒性。
