## 1 Introduction  
Bisphenol A (BPA) is one of the most widely produced chemical products in the world, and is mainly used in epoxy resins, plasticizers, flame retardants, and other chemicals [1, 2, 3, 4], as well as in the production of thermal paper [5] and dental filling materials [6]. About a quarter of the BPA produced is released into the environment during production, transportation, and processing [7], mainly through industrial production and urban sewage discharge [8, 9, 10]. BPA is the most important bisphenol compound detected in wastewater treatment plants (WWTPs) [11]. However, due to the limitations of currently available treatment processes, WWTPs have become the main source of BPA and bisphenol analogs in surface water [12]. In addition, beverage bottles, food packaging bags, and plastic landfill leachate have also become major routes through which BPA enters the environment [13]. Since January 2020, in response to the novel coronavirus epidemic, a large amount of plastic has been utilized in the manufacture and use of virus protective equipment, and the plastic waste generated has increased the environmental risk of BPA emissions [14; 15]. Currently, BPA has been detected in air, water, soil, sediment, indoor dust, and human tissue [16]. In Lake Tai, China, bisphenol concentrations in the lake surface water increased from 4.2-14 ng/L to 27-565 ng/L from 2013 to 2017 [17]. Among bisphenols, BPA accounts for about 27% of the total bisphenols [18]. In the Peba River basin in Palau, Brazil, the BPA concentrations in surface water in the dry and rainy seasons were as high as 1587.7 ng/L and 1057.7 ng/L, respectively [19]. Studies have shown that the average daily intake of BPA in the global population is 38.78 ng/kg bw/day for adults and 51.74 ng/kg bw/day for children [20]. However, BPA exhibits significant endocrine-disrupting toxicity, carcinogenic and mutagenic properties, neurotoxicity, and immunotoxicity. Firstly, BPA exhibits estrogenic activity [21] that can compete with endogenous estradiol to block the estrogen response [22], interfere with the normal metabolic processes of the body [23], and affect reproductive function, mammary gland development, cognitive function, and metabolism [24]. Secondly, BPA can lead to the formation and metastasis of vascular tumors [25], and the development of prostate and ovarian cancers [26]. Thirdly, BPA exposure may negatively affect neurobehavioral functioning in children, including attention-deficit/hyperactivity disorder, and may even trigger symptoms such as aggressive behavior, depression, and anxiety [27]. Finally, BPA can even induce human immune diseases, such as type 1 diabetes. Although there is no uniform standard for the minimum harmful concentration of BPA, the known negative effects of BPA exposure strongly suggest that long-term exposure to BPA will have negative effects on human health [28]. A study by [PERSON] et al. found that the BPA removal efficiency of 25 WWTPs in Canada was 1-77%, and the BPA removal efficiency of WWTPs using secondary treatment processes (including conventional activated sludge, biological aerated filter processes, and membrane bioreactors) was 71% [29]. A previous study also found that the average total removal efficiency of BPA from WWTPs using the secondary biological treatment process in Hong Kong was only about 25.5% [30]. BPA also has an inhibitory effect on the activity of activated sludge [31]. Previous research showed that a high concentration of BPA (53 mg/L) had toxic effects on activated sludge [32], while 100 mg/g BPA in soil significantly inhibited microbial activity and growth [33]. The activated sludge process is widely used in WWTPs. Although it is currently believed that high concentrations of BPA will have toxic effects on activated sludge, the specific toxicity mechanism and the impact on the microbial population structure and ecological niche of activated sludge are still unclear. Existing studies have paid more attention to the removal efficiency and mechanism of BPA by functional strains [34; 35; 36].