Aagaardthomas5824

33%) than those in 40 mg-TOC/L LB broth (60.95%), weakening the competitive superiority of dominant taxa in the patchier biofilms. In addition, the co-occurrence network reflected that the positive interactions among rare genera contributed to exclude dominant genera in 10 mg-TOC/L LB broth, whereas negative interactions only occurred between the dominant Enterobacter and Acinetobacter or rare Comamonas in 40 mg-TOC/L LB broth. This study highlighted the distinctive succession dynamics of dominant and rare genera in biofilms at different substrate concentrations, which would advance our understanding of the biofilm communities in biofilm-related process.Fine particulate matter with an aerodynamic diameter of Cr. These results will help us to further understand how PM2.5 emissions from the exhausts of in-use gasoline-fueled vehicles contribute to both chemical and atmospheric metallic elements concentration in the ambient air.The environment of the countryside is different from that of the city. Studying the abundance, characteristics, and removal of microplastics (MPs) in rural domestic wastewater treatment facilities (RD-WWTFs) is of great significance for understanding the impacts of human activities on the environment of the countryside. Therefore, we studied five such facilities in the Hangzhou region of China. The abundance of MPs in the influent was 430-2154 items/m3. Micro-Raman spectroscopic analysis indicates that the main type of polymer in the influent is polypropylene (PP, 54.6%), followed by polystyrene (PS, 29.7%) and polyethylene terephthalate (PET, 9.7%). The color of MPs is mainly white and clear (62.9%), red (13.3%) and gray (12.0%). Our results show that fragments (71.3%) are the dominant shape of MPs, followed by fibers (21.5%). The characteristics of MPs, such as sizes, shapes, and types, along with the treatment process, affect the removal of MPs in RD-WWTFs. Large MPs are easily removed by anaerobic processes, while small MPs are better removed by anaerobic/anoxic/oxic processes. Fibrous MPs are more difficult to be removed than the fragmented ones. Constructed wetlands play an important role in the removal of MPs.The development of microbial source tracking methods has resulted in an array of genetic faecal markers for assessing human health risks posed from surface water pollution. Leurocristine However, their use as performance metrics at wastewater treatment plants (WWTPs) has not been explored extensively. Here we compared three Bacteroides (HF183, HumM2, AllBac) and two E. coli (H8, RodA) genetic markers for summer and winter performance monitoring at twelve small rural ( less then 250 PE) and three larger WWTPs in NE England. Small WWTPs are of interest because they are poorly understood and their impact on surface water quality may be underestimated. Overall, genetic marker data showed significant differences in treatment performance at smaller versus larger WWTPs. For example, effluent abundances of HF183 and HumM2 were significantly higher in smaller systems (p = 0.003 for HumM2; p = 0.02 for HF183). Genetic markers also showed significant differences in performance between seasons (p less then 0.01, n = 120), with human-specific markers (i.e., HF183, HumM2, H8) being generally better for summer WWTP monitoring. In contrast, Bacteroides markers were much more suitable for winter monitoring, possibly because the E. coli markers are less sensitive to differences in temperature and sunlight conditions. Overall, Bacteroides markers best described WWTP treatment performance across all samples, although seasonal differences suggest caution is needed when markers are used for performance monitoring. Genetic markers definitely provide rapid and new information about WWTP performance, but more spatially diverse studies are needed to refine their use for routine WWTP monitoring.Polychlorinated biphenyls (PCBs) are a kind of persistent organic pollutants (POPs) with stable chemical properties which can be enriched in a biological body for a long time. They are often carelessly released into natural environment and thus constantly posing a potential threat to human health. However, because of lack of effective ways of degrading PCBs, researchers are still striving to explore new approaches to remove them from the environment. In this work, we employed atmospheric-pressure non-thermal dielectric barrier discharge (DBD) plasma to treat 3,3',4,4'-tetrachlorobiphenyl (PCB77) in aqueous solution and investigated the removal efficiency under different DBD conditions using different discharging gases. As a result, we showed that He-DBD had the highest removal efficiency with hydroxyl radical playing the major role in the degradation, while O2-DBD also gave rise to relatively high efficiency with ozone making an important contribution. After 2 min of treatments by He-DBD and O2-DBD, over 75% of PCB77 was degraded with removal rate of 23.65 mg/L and 22.19 mg/L per minute, respectively. Besides, the toxicological evaluation for the DBD treatment was also provided, confirming that the PCB77 degradation products had negligible biotoxicity. This work therefore provides a new effective approach to treatment of persistent organic pollutants (POPs) in the environment.Per- and polyfluoroalkyl substances (PFASs) are known organic pollutants with adverse health effects on humans and the ecosystem. This paper synthesises literature about the status of the pollutants and their precursors, identifies knowledge gaps and discusses future perspectives on the study of PFASs in Africa. Limited data on PFASs prevalence in Africa is available because there is limited capacity to monitor PFASs in African laboratories. The levels of PFASs in Africa are higher in samples from urban and industrialized areas compared to rural areas. Perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) are the dominant PFASs in human samples from Africa. Levels of PFOS and PFOA in these samples are lower than or comparable to those from industrialized countries. PFOA and PFOS levels in drinking water in Africa are, in some cases, higher than the EPA drinking water guidelines suggesting potential risk to humans. The levels of PFASs in birds' eggs from South Africa are higher, while those in other environmental media from Africa are lower or comparable to those from industrialized countries.