College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China.
State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou, 510655, China.
Ecotoxicol Environ Saf. 2020 Sep 1;200:110757. doi: 10.1016/j.ecoenv.2020.110757. Epub 2020 May 23.
Triphenyl phosphate (TPHP) is one of the most widely used organophosphate flame retardants (OPFRs) and is frequently detected in a variety of environmental media. Previous studies reported that TPHP had toxic effects on vertebrates, but little toxic information was available in lower trophic aquatic organisms which were more sensitive to the exposure of many toxic substances. In this study, protozoa Tetrahymena thermophila (T. thermophila) were exposed to 0, 0.01, 0.17 or 2.35 mg/L TPHP for 5 days to study the effects of sub-chronic exposure on theoretical population, cell viability, cell size and number of cilia. Additionally, the effects of TPHP on gene transcription were assessed by transcriptome sequencing technique (RNA-Seq). Cell viability and number of cilia were significantly reduced in all TPHP exposure groups compared with the control. In addition, exposure to 0.17 or 2.35 mg/L TPHP significantly reduced the theoretical population, circumference and body width, and there was a significant decrease in body length in the 2.35 mg/L exposure group. Comparative transcriptome sequencing identified a total of 4105 up- and 4487 down-regulated genes after exposure to 2.35 mg/L TPHP for 5 days compared with the control. KEGG analysis showed that dysfunction of pathways associated with ribosome, spliceosome, phagosome, proteasome and protein processing in endoplasmic reticulum in this study might be responsible for the toxicity of T. thermophila caused by TPHP. In general, the results indicated that TPHP had an adverse effect on the protozoa T. thermophila.
磷酸三苯酯（TPHP）是最广泛使用的有机磷阻燃剂（OPFRs）之一，经常在各种环境介质中检测到。先前的研究表明，TPHP 对脊椎动物具有毒性作用，但在营养层次较低的水生生物中，有关其毒性的信息较少，而这些生物对许多有毒物质的暴露更为敏感。在这项研究中，原生动物嗜热四膜虫（T. thermophila）暴露于 0、0.01、0.17 或 2.35mg/L TPHP 中 5 天，以研究亚慢性暴露对理论种群、细胞活力、细胞大小和纤毛数量的影响。此外，还通过转录组测序技术（RNA-Seq）评估了 TPHP 对基因转录的影响。与对照组相比，所有 TPHP 暴露组的细胞活力和纤毛数量均显著降低。此外，暴露于 0.17 或 2.35mg/L TPHP 显著降低了理论种群、周长和体宽，而在 2.35mg/L 暴露组中体长显著降低。比较转录组测序发现，与对照组相比，暴露于 2.35mg/L TPHP 5 天后，总共有 4105 个上调基因和 4487 个下调基因。KEGG 分析表明，本研究中与核糖体、剪接体、吞噬体、蛋白酶体和内质网中蛋白质加工相关的途径功能障碍可能是 TPHP 引起嗜热四膜虫毒性的原因。总的来说，这些结果表明 TPHP 对原生动物嗜热四膜虫具有不良影响。
