Transformation of sulfamethoxazole by sulfidated nanoscale zerovalent iron activated persulfate: Mechanism and risk assessment using environmental metabolomics.

The threat caused by the misuse of antibiotics to ecology and human health has been aroused an extensive attention. Developing cost-effective techniques for removing antibiotics needs to put on the agenda. In current research, the degradation mechanism of sulfamethoxazole (SMX) by sulfidated nanoscale zerovalent iron (S-nZVI) driven persulfate, together with the potential risk of intermediates were studied. The degradation of SMX followed a pseudo-first order kinetics reaction with kobs at 0.1176 min-1. Both SO4•- and •OH were responsible for the degradation of SMX, and SO4•- was the predominant free radical. XPS analysis demonstrated that reduced sulfide species promoted the conversion of Fe (III) to Fe (II), resulting in the higher transformation rate of SMX. Six intermediates products were generated through hydroxylation, dehydration condensation, nucleophilic reaction, and hydrolysis. The risk of intermediates products is subsequently assessed using E. coli as a model microorganism. After E.coli exposure to intermediates for 24 h, the upmetabolism of carbohydrate, nucleotide, citrate acid cycle and downmetabolism of glutathione, sphingolipid, galactose by metabolomics analysis identified that SMX was effectively detoxified by oxidation treatment. These findings not only clarified the superiority of S-nZVI/persulfate, but also generated a novel insight into the security of advanced oxidation processes.

The global burden of nasopharyngeal carcinoma from 2009 to 2019: an observational study based on the Global Burden of Disease Study 2019.

PURPOSE: The incidence and mortality rate of nasopharyngeal carcinoma (NPC) has changed in recent years. Our goal is to determine the epidemiological pattern of NPC to help policymakers allocate limited medical resources. METHODS: Detailed information about NPC from 2009 to 2019 was collected from the Global Burden of Disease 2019 database. Age-standardized rates (ASRs) and corresponding estimated annual percentage changes (EAPCs) were calculated to assess NPC's incidence and mortality trends. RESULTS: Globally, there was a consistent increase in the NPC incidence cases from 2009 to 2019 (from 121.65 × 103 cases in 2009 to 176.50 × 103 cases in 2019, increasing by 45.09%). The age-standardized incidence rate (ASIR) of NPC increased from 1.81 in 2009 to 2.12 in 2019 (EAPC = 1.59, 95% CI 1.36-1.81). On the contrary, the mortality of NPC showed a downward trend (ASDR: 0.93 in 2009 and 0.86 in 2019; EAPC = - 0.63, 95% CI - 0.78 to - 0.48), and it was negatively correlated with the social demographic index (SDI) in most regions. Both incidence and mortality rates of high-incidence territories tended to be stable or decline. Males had significantly higher incidence and mortality of NPC than females. The number of patients with onset age greater than 50 years old accounted for the highest proportion. We found that smoking, occupational exposure to formaldehyde, and alcohol use were the main risk factors for NPC-related mortality. CONCLUSION: Globally, the incidence rate of NPC has been slightly increasing, while the mortality and disability-adjusted life years (DALYs) have been decreasing. NPC burden in high-middle and middle SDI areas was the heaviest. The current prevention strategy should be repositioned, and some countries should formulate more targeted approaches to reduce the current burden of NPC.

Effect of a low-cost and highly efficient passivator synthesized by alkali-fused fly ash and swine manure on the leachability of heavy metals in a multi-metal contaminated soil.

Soil pollution, caused by heavy metals, is an environmental problem that requires an urgent solution in China. Chemical passivation is a technology that uses various passivators to reduce the availability of heavy metals in soil and realize the remediation of contaminated soil. In this study, we examined the effects of fly ash (FA), alkali-fused fly ash (AFFA), swine manure biochar (SB), and modifying biochar (MB) on the leachability of Cu, Zn, Pb, and Cd via soil culture experiments. The results showed that the addition of AFFA, SB, and MB significantly reduced the extractable contents of Cu, Pb, and Cd in the soil. AFFA and MB had the best passivation effect, followed by SB and FA. The passivation effect on Pb was the best, followed by that on Cu and Cd. AFFA modification significantly improved the passivation effect of MB on Cu, Pb, and Cd in composite contaminated soil. With the addition of 3% MB, the Pb, Cu, and Cd extracted by TCLP decreased by 95.7, 74.1, and 59.1%, respectively. Correlation analysis, Fourier transform infrared spectrometry, scanning electron microscopy, and energy-dispersive X-ray spectroscopy showed that the passivation mechanism is mainly due to an increase in the soil pH, silicate content, and cohesiveness. The soil culture experiments in this study proved that MB is a low-cost and highly efficient organic-inorganic composite passivator for multi-metal contaminated soils.