磷化学工业(PCI)生产过程中产生的大量磷石膏的不当处置仍然存在。磷石膏库存形成的渗滤液可能对生态环境和人类健康构成威胁。然而,关于磷石膏渗滤液对生物体有害影响的信息仍然有限。在这里,分析了磷石膏渗滤液的理化特性,及其对斑马鱼(Daniorerio)的毒性作用,特别是在肝毒性和潜在机制方面,进行了评估。结果表明,P,NH3-N,TN,F-,As,Cd,Cr,Co,Ni,Zn,Mn,磷石膏渗滤液中的汞不同程度地超过了地表水环境质量标准(GB3838-2002)的V级。急性毒性试验表明,磷石膏渗滤液对斑马鱼的96hLC50值为2.08%。在暴露于磷石膏渗滤液的情况下,斑马鱼表现出浓度依赖性肝损伤,以空泡化和炎症细胞浸润为特征。肝脏中丙二醛(MDA)含量的增加和抗氧化酶活性的改变表明氧化应激和氧化损伤的诱导。凋亡相关基因的表达(P53,PUMA,Caspase3,Bcl-2和Bax)在低剂量组上调,在中,高剂量组下调,提示肝细胞凋亡或坏死的发生。此外,磷石膏渗滤液通过降低拟杆菌的相对丰度影响斑马鱼肠道菌群的组成,气单胞菌,黄杆菌,弧菌,并增加了红杆菌属细菌和Pirellula的含量。相关分析表明,肠道菌群失调与磷石膏渗滤液诱导的肝毒性有关。总之,接触磷石膏渗滤液导致斑马鱼肝脏损伤,可能通过氧化应激和细胞凋亡,与肠道菌群也起着很大的作用。这些发现有助于了解磷石膏渗滤液的生态毒性,促进PCI的可持续发展。
The improper disposal of large amounts of phosphogypsum generated during the production process of the phosphorus chemical industry (PCI) still exists. The leachate formed by phosphogypsum stockpiles could pose a threat to the ecological environment and human health. Nevertheless, information regarding the harmful effects of phosphogypsum leachate on organisms is still limited. Herein, the physicochemical characteristics of phosphogypsum leachate were analyzed, and its toxicity effect on zebrafish (Danio rerio), particularly in terms of hepatotoxicity and potential mechanisms, were evaluated. The results indicated that P, NH3-N, TN, F-, As, Cd, Cr, Co, Ni, Zn, Mn, and Hg of phosphogypsum leachate exceeded the V class of surface water environmental quality standards (GB 3838-2002) to varying degrees. Acute toxicity test showed that the 96 h LC50 values of phosphogypsum leachate to zebrafish was 2.08 %. Under exposure to phosphogypsum leachate, zebrafish exhibited concentration-dependent liver damage, characterized by vacuolization and infiltration of inflammatory cells. The increased in Malondialdehyde (MDA) content and altered activities of antioxidant enzymes in the liver indicated the induction of oxidative stress and oxidative damage. The expression of apoptosis-related genes (P53, PUMA, Caspase3, Bcl-2, and Bax) were up-regulated at low dosage group and down-regulated at medium and high dosage groups, suggesting the occurrence of hepatocyte apoptosis or necrosis. Additionally, phosphogypsum leachate influenced the composition of the zebrafish gut microbiota by reducing the relative abundance of Bacteroidota, Aeromonas, Flavobacterium, Vibrio, and increasing that of Rhodobacter and Pirellula. Correlation analysis revealed that gut microbiota dysbiosis was associated with phosphogypsum leachate-induced hepatotoxicity. Altogether, exposure to phosphogypsum leachate caused liver damage in zebrafish, likely through oxidative stress and apoptosis, with the intestinal flora also playing a significant role. These findings contribute to understanding the ecological toxicity of phosphogypsum leachate and promote the sustainable development of PCI.