Spatial distribution, receptor modelling and risk assessment of organophosphate esters in surface water from the largest freshwater lake in China.

The occurrence and risk of organophosphate esters (OPEs) has become a global concern in recent years. This study investigated the occurrence, spatial distribution, and potential sources of thirteen OPEs and their associated ecological and human health risks in water samples from the largest freshwater lake, Poyang Lake, together with its five major inflow rivers and the water channel to Yangtze River. The total OPEs concentrations ranged from 38.44 ng/L to 428.94 ng/L, and the largest tributary Ganjiang River was much more polluted than other rivers. Chlorinated OPEs, such as tris (1-chloro­2-propyl) phosphate and tri (2-chloroethyl) phosphate occupied the dominant composition of OPEs in the research area. Principal component analysis with multiple linear regression, positive matrix factorization, and correlation analysis were used to apportion the potential sources of OPEs in surface water. The combined contribution of polyvinyl chloride, polyester resins, and polyurethane foam (68.64%), antifoam agent and hydraulic fluids (21.50%), and the release of decorative materials and electric equipment from indoor (9.86%) were identified as the OPEs sources in the study region. The risk quotients (RQs) showed the ecological risk was negligible, but 2-ethylhexyl diphenyl phosphate exposures posed medium ecological risk to aquatic organisms. The carcinogenic and non-carcinogenic risks of the target OPEs were below the theoretical risk threshold values, however, toddlers were much more sensitive to the OPEs exposure in surface water than teenagers and adults. Oral ingestion was the principal exposure pathway, and the health risk via oral ingestion was 1-2 orders of magnitude higher than dermal contact exposure route.

In-situ fabrication of Ag/P-g-C3N4 composites with enhanced photocatalytic activity for sulfamethoxazole degradation.

A series of Ag/P-g-C3N4 composites with different Ag content were synthesized for the first time by thermal polymerization combined with photo-deposition method. The composites were characterized by X-ray powder diffraction, field emission scanning electron microscope coupled with energy-dispersive X-ray spectroscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, ultraviolet-visible diffuse reflectance spectra, N2 absorption-desorption and X-ray photoelectron spectroscopy. Ag was successfully dispersed on the surface of P-g-C3N4. The photocatalytic performance of P-g-C3N4 and Ag/P-g-C3N4 was evaluated by degrading sulfamethoxazole (SMX) under visible light irradiation. In the presence of 5% Ag/P-g-C3N4, 100% of SMX was degraded within 20 min. The enhanced photocatalytic activity of Ag/P-g-C3N4 was attributed to the surface plasmon resonance effect of metallic Ag and Schottky barrier formed on the interface between Ag and P-g-C3N4, which could speed up the generation rate of electrons and holes and inhibit the recombination of photogenerated electron-hole pairs. The radical quenching tests indicated that holes and superoxide radicals were the dominant active species involved in SMX degradation. The synthesized materials maintained high catalytic activity after five cycle runs. The concentration and the intermediates during the degradation process were determined by LC-MS/MS, and the tentative degradation pathways of SMX in photocatalytic system were proposed.

Dynamic transport of antibiotics and antibiotic resistance genes under different treatment processes in a typical pharmaceutical wastewater treatment plant.

The propagation of antibiotic resistance is a challenge for human health worldwide, which has drawn much attention on the reduction of the resistance genes. To understand their occurrence during different treatment processes, in this study, four classes of antibiotics (tetracyclines, sulfonamides, quinolones, and macrolides), eight antibiotic resistance genes (ARGs) (tetB, tetW, sul1, sul2, gyrA, qepA, ermB, and ermF), and two mobile elements (int1 and int2) were investigated in a typical pharmaceutical plant. The total concentrations of antibiotics were detected in the range of 2.6 × 102 to 2.5 × 103 ng/L in the treatment processes, and the high abundance of ARGs was detected in the biological treatment unit. The dynamic trend analysis showed that antibiotics were partially removed in the anaerobic/aerobic processes, where ARGs were proliferated. The abundance of tetB and gyrA genes was positively correlated with pH and EC (p < 0.05), and the tetW, sul1 and sul2 genes were significantly correlated with TOC, TN, and DO (p < 0.05), indicating the influence of physicochemical properties of the solution on the levels of ARG subtypes. The phylogenetic analysis showed that the tetW clones had high homology with some pathogenic microorganisms, such as Klebsiella pneumonia and Neisseria meningitides, which would threaten human health. Results indicated that the horizontal transfer acted as a major driver in the ARGs evolution.

Regulatory roles of OASL in lung cancer cell sensitivity to Actinidia chinensis Planch root extract (acRoots).

Lung cancer is one of the most common malignancies worldwide. Actinidia chinensis Planch root extract (acRoots) was found to have the capacity of the anti-tumor, although the molecular mechanisms remain unclear. The present study aims to investigate the molecular mechanisms by which lung cancer cells sense to inhibitory effects of acRoots with a special focus on immune-associated gene profiles. We firstly provide a preclinical evidence that acRoots can significantly inhibit lung cancer cell proliferation and apoptosis via the PI3K-OASL signal pathway. The heterogeneous alterations of immune-associated gene profiles of lung cancer cell types were measured after treatment with various doses of acRoots. The OASL gene was identified as the key regulator in molecular networks of acRoots-treated lung cancer cells and validated. The OASL gene plays an important role in the regulation of lung cancer cell sensitivity to acRoots, which modulated by the PI3K signal pathway. Thus, our data indicate that OASL can be one of the decisive regulators to maintain lung cancer cell susceptibility to acRoots and may be associated with the development of drug resistance. The regulation of OASL can be an alternative strategy to improve drug efficacy during cancer therapies.