Triphenyltin (TPT) is widely used as an active ingredient in antifouling paints and fungicides, and continuous release of this highly toxic endocrine disruptor has caused serious pollution to coastal marine ecosystems and organisms worldwide. Using bioassays and transcriptome sequencing, this study comprehensively investigated the molecular toxicity of TPT chloride (TPTCl) to the marine mussel Perna viridis which is a commercially important species and a common biomonitor for marine pollution in Southeast Asia. Our results indicated that TPTCl was highly toxic to adult P. viridis, with a 96-h LC10 and a 96-h EC10 at 18.7 μg/L and 2.7 μg/L, respectively. A 21-day chronic exposure to 2.7 μg/L TPTCl revealed a strong bioaccumulation of TPT in gills (up to 36.48 μg/g dry weight) and hepatopancreas (71.19 μg/g dry weight) of P. viridis. Transcriptome analysis indicated a time course dependent gene expression pattern in both gills and hepatopancreas. Higher numbers of differentially expressed genes were detected at Day 21 (gills 1686 genes; hepatopancreas 1450 genes) and at Day 28 (gills 628 genes; hepatopancreas 238 genes) when compared with that at Day 7 (gills 104 genes, hepatopancreas 112 genes). Exposure to TPT strongly impaired the endocrine system through targeting on nuclear receptors and putative steroid metabolic genes. Moreover, TPT widely disrupted cellular functions, including lipid metabolism, xenobiotic detoxification, immune response and endoplasmic-reticulum-associated degradation expression, which might have caused the bioaccumulation of TPT in the tissues and aggregation of peptides and proteins in cells that further activated the apoptosis process in P. viridis. Overall, this study has advanced our understanding on both ecotoxicity and molecular toxic mechanisms of TPT to marine mussels, and contributed empirical toxicity data for risk assessment and management of TPT contamination.The permeable (sandy) sediments that dominate the world's coastlines and continental shelves are highly exposed to nitrogen pollution, predominantly due to increased urbanisation and inefficient agricultural practices. This leads to eutrophication, accumulation of drift algae and changes in the reactions of nitrogen, including the potential to produce the greenhouse gas nitrous oxide (N2O). Nitrogen pollution in coastal systems has been identified as a global environmental issue, but it remains unclear how this nitrogen is stored and processed by permeable sediments. We investigated the interaction of drift algae biomass and nitrate (NO3-) exposure on nitrogen cycling in permeable sediments that were impacted by high nitrogen loading. We treated permeable sediments with increasing quantities of added macroalgal material and NO3- and measured denitrification, dissimilatory NO3- reduction to ammonium (DNRA), anammox, and nitrous oxide (N2O) production, alongside abundance of marker genes for nitrogen cycling anigation strategies for marine eutrophication.Chemical nitrogen (N) fertilizer is essential for achieving high yield in winter wheat. However, the over-use of N fertilizer not only significantly reduces N use efficiencies (NUEs) but also leads to serious environmental concerns. An efficient N fertilizer management is thus urgently required for mitigating NH3 volatilization and increasing grain yield and NUEs of wheat. A 3-year field study using 15N stable isotopes was conducted to evaluate the fate of 15N-labelled fertilizer and to investigate the NH3 flux, grain yield, yield-scaled NH3 emissions and NUEs of various N application rates under two different application techniques comprising split-N method (basal N plus top-dressed N application) and pre-plant-only (without top-dressed N). Daily NH3 fluxes peaked within one week after basal N fertilizer application. Total NH3 volatilization, NH3 emission factor (EF) and yield-scaled NH3 emission were enhanced significantly with an increase in N application rates. Pre-plant-only N method greatly increased total NH3 volatilization, NH3 EF and yield-scaled NH3 emission by 43%, 58% and 63%, respectively, compared with split-N method when averaged across N application rates and years. The residual 15N in soil and the unaccounted 15N losses were greater under pre-plant-only N method and under high N application rate compared with split-N method and under low N application rate, respectively. Higher values of unaccounted 15N loss (nearly 50% of the total N applied) and residual 15N (27% of the total N applied) were the major contributors to lower NUEs, that could be predominantly attributed to the higher NH3 emission under elevated N application rate and pre-plant-only N method. Considering the overall environmental impact and yield performance, 120 kg N ha-1 in combination with split-N method could be recommended for improving the overall economic return and mitigating environmental pollution to ensure cleaner production of winter wheat.Due to the spread of coronavirus disease 2019 (COVID-19), large amounts of antivirals were consumed and released into wastewater, posing risks to the ecosystem and human health. Ozonation is commonly utilized as pre-oxidation process to enhance the disinfection of hospital wastewater during COVID-19 spread. In this study, the transformation of ribavirin, antiviral for COVID-19, during ozone/PMS‑chlorine intensified disinfection process was investigated. •OH followed by O3 accounted for the dominant ribavirin degradation in most conditions due to higher reaction rate constant between ribavirin and •OH vs. SO4•- (1.9 × 109 vs. 7.9 × 107 M-1 s-1, respectively). During the O3/PMS process, ribavirin was dehydrogenated at the hydroxyl groups first, then lost the amide or the methanol group. Chloride at low concentrations (e.g., 0.5- 2 mg/L) slightly accelerated ribavirin degradation, while bromide, iodide, bicarbonate, and dissolved organic matter all reduced the degradation efficiency. KU-60019 In the presence of bromide, O3/PMS process resulted in the formation of organic brominated oxidation by-products (OBPs), the concentration of which increased with increasing bromide dosage. However, the formation of halogenated OBPs was negligible when chloride or iodide existed. Compared to the O3/H2O2 process, the concentration of brominated OBPs was significantly higher after ozonation or the O3/PMS process. This study suggests that the potential risks of the organic brominated OBPs should be taken into consideration when ozonation and ozone-based processes are used to enhance disinfection in the presence of bromide amid COVID-19 pandemic.