基于环境浓度下溴代偶氮染料和代谢产物对斑马鱼的多代慢性毒性及毒性通路的机制研究

Organobromine compounds in the environment are highly concerned because of their persistence, bioaccumulation and toxicity. Compared with brominated flame retardants, brominated azo dyes is an important but neglected bromine compounds. China is the world's largest country for dye production and uses. Due to massive production and widely use, azo dyes can be released into the environment. These compounds are toxic, and the metabolites of some azo dyes exhibited a greater toxicity than their parent compound, posing potential adverse effects to environmental organisms and human health. However, toxicology studies regarding brominated azo dyes on aquatic organisms are very limited and their long-term chronic effects and the mechanisms are unknown. Therefore, this study aims to explore the multigenerational chronic impacts of brominated azo dyes and their metabolites on zebrafish at environmentally relevant concentrations. Their differences in genotoxicity, reproductive toxicity，developmental toxicity and endocrine disrupting effects as well as molecular mechanisms are compared. Quantitative analysis is used to assess the bioaccumulation and metabolism of these compounds in organisms. The contribution of parent compound and metabolites to toxicity is also calculated. In addition, toxicity pathways for adverse effects and key targets are identified to further complement the AOP framework. This study provides scientific basis for the environmental pollution assessment and ecological risk assessment of these compounds.

环境中溴代有机物由于其持久性、生物富集性及生物毒性受到高度关注。与溴代阻燃剂相比，溴代偶氮染料是一类重要却被忽视的溴代有机物。我国是世界第一大染料生产和使用大国，由于大量生产和广泛应用，偶氮染料被释放到环境介质中。这些物质具有生物毒性和遗传毒性，部分偶氮染料的还原代谢产物表现出比母体化合物更强的生物毒性，对环境生物和人类健康构成了潜在危害。但目前缺乏溴代偶氮染料对水生生物的毒理学研究，且长期慢性毒性效应和致毒机制不明。因此，本项目旨在解析溴代偶氮染料和代谢产物在实际环境浓度暴露下对斑马鱼的多代慢性毒性。比较二者遗传毒性、生殖发育毒性和内分泌干扰效应及分子机制的差异。采用定量分析技术评估化合物在生物体内富集和代谢规律，推算母体化合物和代谢产物的致毒比例。同时识别与毒性效应相关的毒性通路和关键靶点，进一步补充和完善AOP框架，为该类化合物的环境污染评估和生态风险评价提供基础数据和科学依据。

溴代偶氮染料是一类重要却被忽视的溴代有机物。为了解溴代偶氮染料DB79和代谢产物BDNA在环境浓度暴露下的多代慢性毒性、累积效应、隔代影响和毒性机制，揭示与毒性相关的毒性通路和分子机制，本项目系统开展了DB79和BDNA暴露对斑马鱼多代慢性毒性和大鼠亚慢性毒性两项研究。主要发现（1）BDNA暴露对斑马鱼的多代生殖发育与遗传毒性整体大于DB79，且对雌性的影响高于雄性。如DB79对F0代斑马鱼产卵量无影响，而BDNA使F0代斑马鱼产卵量显著降低；高剂量DB79可显著延缓F1代斑马鱼胚胎孵化，而 BDNA使F1代斑马鱼的性分化偏向雄性等；DB79对F2代斑马鱼无影响，而高浓度BDNA可使F2代斑马鱼出现受精率降低、孵化率降低等生殖发育毒性效应。（2）影响的关键毒性通路和分子靶点包括：影响F0、F1代成鱼生殖发育过程、肽链内切酶抑制剂活性、精子酵素结合等通路；F1、F2代幼鱼蛋白水解、代谢传导过程、DNA损伤修复及信号转导等通路的关键分子表达水平变化。（3）DB79和BDNA暴露对大鼠有肝肾毒性和内分泌干扰效应，且BDNA毒性强于DB79。BDNA毒性效应具有明显性别差异，这可能与暴露后雌雄血清浓度水平不同有关。同时雄雌的毒代动力学过程差异显著，雄性大鼠特异性活化亚油酸代谢，D-谷氨酰胺与D-谷氨酸代谢两条代谢通路；雌性大鼠特异性活化苯丙氨酸、酪氨酸和色氨酸生物合成，β-丙氨酸代谢两条代谢通路。（4）采用定量化学分析技术评估二者在生物体内富集和代谢规律，发现DB79暴露大鼠血清并未检出BDNA，结合斑马鱼检测结果，提示溴代偶氮分散染料的主要代谢产物不是BDNA，其毒性效应并非由BDNA介导。（5）本研究补充和完善了偶氮染料和BDNA引起生殖发育毒性和内分泌干扰效应的AOP框架，将为该类化合物的环境污染评估和生态风险评价提供重要基础数据和科学依据。.基于此课题，项目申请人及参与人已发表文章4篇，其中SCI 论文3篇。另有2篇SCI文章撰写中。