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Lipid metabolism could be used as a biomarker for environmental monitoring of metal pollution, including Cu. Given the potential role of the Wnt/β-catenin signaling pathway and acetylation in lipid metabolism, the aim of this study was to investigate the mechanism of Wnt signaling and acetylation mediating Cu-induced lipogenesis. Grass carp Ctenopharyngodon idella, widely distributed freshwater teleost, were used as the model. We found that waterborne Cu exposure increased the accumulation of Cu and lipid, up-regulated lipogenesis, suppressed Wnt signaling, reduced β-catenin protein level and its nuclear location, reduced the sirt1 mRNA levels and up-regulated the β-catenin acetylation level. Further investigation found that Cu up-regulated lipogenesis through Wnt/β-catenin pathway; Cu regulated the β-catenin acetylation, and K311 was the key acetylated residue after Cu incubation. SIRT1 mediated Cu-induced changes of acetylated β-catenin and played an essential role in nuclear accumulation of β-catenin and Cu-induced lipogenesis. Cu facilitated lipid accumulation via the regulation of Wnt pathway by SIRT1. For the first time, our study uncovered the novel mechanism for Wnt/β-catenin pathway and β-catenin acetylation levels mediating Cu-induced lipid deposition, which provided insights into the association between Cu exposure and lipid metabolism in fish and had important environmental implications for monitoring metal pollution in the water by using new biomarkers involved in lipid metabolism. Tetrabromobisphenol-A (TBBPA) is an emerging organic pollutant and a commonly used brominated flame retardant that has received much attention owing to its toxicity. SP 600125 negative control in vivo Although TBBPA is ubiquitously detected in atmospheric particulate matter and dust, few studies have investigated the sub-chronic inhalation exposure to TBBPA. To further understand the excretion characteristics and tissue accumulation of TBBPA after inhalation exposure, we used the rat model to conduct a sub-chronic inhalation exposure study. Male rats were administered with different doses of aerosol TBBPA (12.9, 54.6, 121.6, and 455.0 mg/m3). TBBPA was found in the excretion (feces and urine) and all the target tissues (lung, liver, heart, thymus gland, spleen, testicles, muscles, kidneys, brain and serum). Feces were the main route of excretion, which contributed 19.18% to 72.54% (urine less then 0.10%). TBBPA excretion through feces following inhalation administration was much higher than that following oral and dermal exposure, thereby indicating lower bioavailability of TBBPA under inhalation exposure. Liver and serum showed higher levels of TBBPA compared with those of other tissues, thereby suggesting tissue-specific accumulation of TBBPA in rats. Owing to the relative non-invasiveness of serum sampling and greatest TBBPA concentration among the tissues, serum is a suitable matrix for estimation of TBBPA bioaccumulation after inhalation exposure. The widespread usage of plastic film increased the content of phthalic acid esters (PAEs) in the environment, causing PAE residue in vegetables and subsequently increasing health risks to humans when consuming them. In this work, the presence, distribution and risk assessment of 15 PAEs in soils and peppers from suburban plastic film pepper-growing greenhouses were investigated. The total PAE contents in soil and pepper samples ranged from 320.1 to 971.2 μg/kg (586.3 μg/kg on average) and from 196.6 to 304.2 μg/kg (245.4 μg/kg on average), respectively. Di (2-ethyl)hexyl, dibutyl and diisobutyl phthalates (DEHP, DnBP and DiBP, respectively) were the most abundant in both soil and pepper samples. Specifically, DEHP showed the highest content in soils, while the DnBP content was the highest in peppers. The total PAE content in soils from pepper-greenhouses was much lower than in the agricultural soils mulched with plastic films, but significantly higher than in the agricultural soils from open uncovered fields. The total PAE content in peppers decreased as the service life of plastic film greenhouses increased. Correlation analysis suggested that the difference in distribution and accumulation behaviors of individual PAEs in greenhouse systems was correlated with their physicochemical properties. The non-cancer and carcinogenic risks of priority PAEs show low risks of PAEs detected in pepper and soil samples from the suburban plastic film greenhouses to human health. Large molecular weight pig biogas slurry (L-PBS) and small molecular weight pig biogas slurry (S-PBS) were separated from original pig biogas slurry (O-PBS) using a 100 kDa membrane. The original bioavailability and biosafety of L-PBS was very low. In order to enhance the total bioavailable dissolved organic nitrogen (TB-DON) and total bioavailable dissolved organic phosphorus (TB-DOP), optimum catalytic ozonation of L-PBS conditions were determined using Box-behnken design models (P  less then  0.0001) and intersection tests. The optimal values for ozone concentration, pH value, active catalyst concentration and reaction time were 2.63 mg·L-1, 6.48, 1.43 g·L-1 and 40 min, respectively. Catalytic ozonation can effectively decompose and transform 68.07% of L-PBS into S-PBS to improve content organic bioavailability, with a molecular weight distribution of 0-1 kDa (13.53%), 1-5 kDa (16.62%), 5-10 kDa (11.16%), 10-30 kDa (11.73%), 30-100 kDa (15.04%). Catalytic ozonation of L-PBS can reduce protein levels from 85.28% to 47.18%, but increases the proportion of fulvic and humic components from 10.22% to 32.67% and 4.51%-20.15%, respectively. Because catalytic ozonation changes the internal components and molecular weights of L-PBS, both saw increases in TB-DON and TB-DOP from 3.33% to 41.12% and 2.43%-37.88%, respectively, with a large number of TB-DON and TB-DOP derived from hydrophilic organic components during catalytic ozonation. These important internal mechanisms changed by catalytic ozonation can effectively reduce the ecotoxicity (IR, from 76.5% to 33.1%) and phytotoxicity (GI, enhanced from 35.4% to 70.3%) of L-PBS. Therefore, catalytic ozonation combined with membrane separation is a choice technology in improving the nutrition of biogas slurry and reduce its ecological risk.