| The rapid development of modern society has brought unprecedented convenience to human life,and the foundation that supports the highly rich material life of modern times is the increasingly developed modern industrial system.Chemical products have become an important component of our daily lives.When producing and using these products,multiple trace pollutants are simultaneously emitted into the environment,among which endocrine disrupting chemicals（EDCs）are a typical type of pollutant.EDCs are exogenous chemicals that interfere with the endocrine system,targeting the endocrine system and exhibiting hormonal-like effects.They do not require high doses of exposure to cause endocrine imbalances in organisms,resulting in various abnormal phenomena and pathological features.EDCs mainly include various categories such as p-hydroxybenzoates,phthalates,bisphenols,organophosphorus insecticides,perfluoroalkanes,etc.,with a wide variety of types and sources.Five typical representative components including bisphenol A（BPA）,di（2-ethylhexyl）phthalate（DEHP）,mono（2-ethylhexyl）phthalate（MEHP）,2-hydroxy-4-methoxy benzophenone（BP3）and 17α-Ethylenylestradiol（EE2）were selected in ths paper and gavage administered to female and male rats,thus exposing them to the five EDCs mentioned above.The mid-term and long-term toxicity of EDCs was evaluated.The toxic effects of the five EDCs on various major organs were preliminarily evaluated through HE staining of pathological sections.The reproductive toxicity of the above five EDCs and the possible in vivo processes and pathways involved were predicted and analyzed by network toxicology methods.The hormone levels in rats were analyzed using HPLC-QQQ-MS,and the effects of the above five EDCs on hormone levels in rats were studied and analyzed.The effects of the above five EDCs on the gut microbiota composition in rats were detected using 16S r RNA gene sequencing method.Finally,based on the mechanism of semiconductor sonocatalysts,new type of composite semiconductor catalyst materials was designed and synthesized.Under the action of ultrasound,the EDC target pollutants such as BPA in the water environment were eliminated through catalytic oxidation,and new catalyst materials with practical potential for treating EDCs pollution in water was found.From the mid-term and long-term toxicity evaluation results of EDCs,it was showed that after 60 days of gavage administration of the above five EDCs,there were no significant abnormalities in the weight of rats in the BPA,DEHP,MEHP,and BP3 groups.The weight of the EE2 group continued to decrease with significant differences compared to the other groups（p<0.05）.Pathological changes caused by toxic effects of EDCs were found in the heart,lung,and kidney sections from HE staining section results.Among them,all of BPA,MEHP,and BP3 caused damage to the myocardium,both of BP3 and EE2caused damage to the lungs and kidneys.In addition,the pathological results of the liver,testicles,and uterus showed that all of these tissues were affected by five EDCs.The pathological changes produced by the testes and uterus indicated that these five EDCs have varying degrees of toxicity to the reproductive system,and EE2 exhibited a higher degree of damage to the uterus than the other four EDCs.Therefore,this paper focused on the reproductive system toxicity of five EDCs and conducted subsequent toxicity studies based on this.Through network toxicology prediction it was found that the body’s response to hormones,reproductive structure development,gland development and other biological processes,as well as prostate cancer related pathways,steroid hormone biosynthesis pathways,and progesterone mediated oocyte maturation related pathways,were involved in the toxic effects of the above five EDCs on the reproductive system.These biological processes and pathways in vivo are closely related to sex hormones,therefore,hormone levels in rats were detected and analyzed.The effects of five EDCs on the levels of eight hormones in female and male rats were tested by HPLC-QQQ-MS,and the differences and similarities in the effects of five EDCs on hormone levels in rats were compared and analyzed.All of the five EDCs showed impact on hormone levels in rats.The levels of hydroxyprogesterone,pregnenolone,progesterone,etiocholanolone,androstanolone,dehydroepiandrosterone and estradiol were significantly changed by EDCs（p<0.05）.The effects of EE2 showed significant gender differences,with changes in the levels of five hormones including hydroxyprogesterone,pregnenolone,etiocholanolone,androstanolone,dehydroepiandrosterone in the male group,while only two hormones including hydroxyprogesterone and progesterone were changed in the female group.EDCs promoted the conversion of pregnenolone to progesterone by regulating the biosynthesis pathway of sex hormones,and interfered with the subsequent conversion of various sex hormones,which resulted in significantly decreasing（p<0.05）of hydroxyprogesterone,pregnenolone,etiocholanolone,androstanolone and dehydroepiandrosterone levels and significantly increasing（p<0.05）of progesterone levels.The downregulation of multiple sex hormones can lead to endocrine disorders,abnormal secondary sexual characteristics,decline or even loss of reproductive system function in biological individuals.The abnormal upregulation of progesterone can make female individuals difficult to conceive,and can also lead to female masculinization and male feminization.The pathways by which EDCs regulate the aforementioned sex hormones are mainly through the androgen and estrogen metabolism pathway,steroidogenesis pathway,androstenedione metabolism pathway,and estrone metabolism pathway.These four pathways involve the biosynthesis and metabolic processes of sex hormones,which includes the complete process from the synthesis of sex hormones to metabolic elimination.The sequencing results of rat gut microbiota and the detection of short chain fatty acid content showed that all five EDCs can reduce the diversity of gut microbiota in rats,and the species category of gut microbiota.BP3 had the deepest and EE2 had the least impact on gut microbiota diversity.At the phylum level,all EDCs administration groups showed significant changes in the gut microbiota composition structure,indicating a significant decrease in the abundance of Proteobacteria.At the genus level,the Clostridiaceae Clostridium exhibited significant gender differences,influenced by EDCs,which are upregulated in the male group and downregulated in the female group.Due to the main influence of this genus,the overall levels of short chain fatty acids in male rats were upregulated（p<0.05）,while the overall levels in female groups were downregulated（p<0.05）.However,the DEHP group showed a unique and more severe impact effect,with significantly upregulating the levels of short chain fatty acid content in both female and male group of rats（p<0.05）.The above changes will affect the balance of hormone levels in the body and alter the content of sex hormones through the direct effect of gut microbiota on the sex hormones entering the intestine and the indirect effect of short chain fatty acids secreted by the gut microbiota itself.The abundance of Clostridiaceae Clostridium is related to changes in estrogen content,while the abundance of Ruminococcaceae Ruminococcus in the dominant genus is related to changes in androgens such as testosterone and 5α-dihydrotestosterone.Changes in the structure of gut microbiota can regulate changes in different hormone levels and have a profound impact on the reproductive system.Developing new catalysts to treat EDCs pollution in water environment is an effective method to treat the pollution of EDCs in the aqueous environment.Stable and effective sonocatalytic active materials such as Ag2O/Cu WO4 composites,Cu S/Ba WO4 composites and Bi OBr/Bi Fe O3 composites were synthesized by hydrothermal synthesis and precipitation methods in this paper.The above composite materials were characterized through various characterization methods,confirming the successful synthesis of the materials and characterizing their various properties.Using EDCs such as BPA as targets,experiments were conducted on sonocatalytic degradation in an aqueous environment,and excellent sonocatalytic degradation capabilities were demonstrated.The degradation rate of Ag2O/Cu WO4 composite material for sonocatalytic degradation of target pollutants could reach 66.31%±3.25%.The degradation rate of target pollutants in the sonocatalytic degradation of Cu S/Ba WO4 composite material could reach 76.83%±1.46%,and the degradation rate increased to 98.75%±0.21%when combined with persulfate.The degradation rate of target pollutants by sonocatalysis of Bi OBr/Bi Fe O3 composite material could reach 77.50%±0.87%,and the degradation rate could be increased to 90.63%±3.31%when combined with persulfate.In the system added with Cu S/Ba WO4 composite,holes and hydroxyl radical will be generated to oxidize and degrade the target.In the system added with Bi OBr/Bi Fe O3 composite,holes,hydroxyl radical and superoxide anion will be generated to oxidize and degrade the target.The construction of the above composite materials improved the drawbacks of a single semiconductor compound,increased the catalytic effect of the catalyst,and has potential value in developing environmentally friendly catalytic degradation materials for EDCs. |
