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Furthermore, analysis of microbial communities in two enrichment cultures, which were constructed from sediment samples with Sb(V) reduction ability under the minimum sulfate condition and maintained Sb(V) removal ability during 28-d enrichment process, revealed possible contribution of several microbial taxa such as Azospira, Chlostridium, Dechloromonas, Dendrosporobacter, and Halodesulfovibrio to Sb(V) reduction in sediment microbial communities.The soil-rice system in rural and peri-urban areas of the lower Brahmaputra valley, northeast India was investigated for heavy metal(loid)s using Nemerow's pollution index (PIN) and potential ecological risk index (RI). Potential health risk due to rice consumption grown in the region was assessed in terms of carcinogenic and non-carcinogenic risks. check details Around 95% of the soil showed acidic nature that ranged from weakly acidic to strongly acidic soil. In terms of PIN, 27.3% of the sampling sites were heavily polluted (PIN≥3), 34.8% moderately, and 37.9% were slightly polluted. The Pb concentration was comparably higher in 57.1% of the rice grain samples and the mean As level (0.17 mg kg-1) was close to the WHO limit. The non-carcinogenic risk in terms of hazard quotient (HQ) was high primarily due to As (HQ > 1), whereas other metals had limited contribution (HQ less then 1). The carcinogenic risk based on total cancer risk (TCR) values for adults and children ranged between 0.0039 - 0.019 and 0.0043-0.0211, respectively, exceeding the maximum acceptable level of 1 × 10-4. Among the rice varieties, for non-carcinogenic risks, the maximum hazard index (HI) was noticed for Bahadur and the minimum for Ranjit. Whereas for carcinogenic risks, the maximum TCR was observed for Mahsuri and the minimum for Moynagiri.Despite the large number of recent studies on microplastics (MPs) and their ability to act as carriers of pollutants, the knowledge about the biological effects of MPs loaded with chemicals is scarce. The aim of this study was to evaluate the potential of MPs as vectors for the antimicrobial triclosan (TCS). For it, we tested low-density polyethylene (LDPE), polyamide (PA), polyethylene terephthalate (PET), polyoxymethylene (POM), polypropylene (PP), polystyrene (PS) and the biodegradable polylactic acid (PLA). Thus, chemical analysis of sorption and desorption of TCS by these MPs was evaluated. The effect of TCS-loaded MPs to Anabaena sp. PCC7120, a cyanobacterium model of primary producers in freshwater ecosystems, was investigated. Chemical analyses showed different capacity of sorption depending on the MP type, which was related to some of their physicochemical properties. PA (104.7 μg/g), POM (57.4 μg/g) and LDPE (18.3 μg/g) were the polymers that sorbed the highest amounts of TCS. Glass transition temperature of polymers and their physicochemical interaction with TCS explained the extent of sorption. Significant decreases were found in growth, 22.3%, 94.6% and 81.0%, and chlorophyll a content, 58.4%, 95.0% and 89.6%, of Anabaena when exposed to TCS-loaded LDPE, PA and POM beads, respectively, which were the only MPs displaying significant sorption-desorption of TCS, implying that these MPs could act as vectors of TCS towards freshwater microalgae. This finding is of fundamental relevance as microalgae are at the base of the aquatic trophic chain and support growth of upper organisms.Investigation of human exposure pathways to PCB in a high-rise estate in Denmark motivated an experiment with sorption of PCB from air to settled house dust. Three sieved house dust samples ( less then 75 μm) of different origin were exposed to elevated air concentrations of PCB in a vacated apartment from seven to 40 days. Within the 40 days, most of the dust samples were close to equilibrium for the congeners PCB-8 to -101 and dust-air partition coefficients were determined. The dust samples of different origin showed comparable partitioning, though small differences were seen. The determined partition coefficients were in agreement with values found in literature. Further, the partition coefficients were compared to three sets of predicted estimates based on absorption of PCB into the organic matter of the dust and octanol-air partition coefficients derived from different sources. Comparing measured and predicted values (log-log), two sets of predicted values showed strong correlation, though overestimated 20-40%, while one set showed similar absolute levels, but with a few deviating congeners. Dust-air ratios were calculated for samples taken from a field investigation in homes with elevated air concentrations of PCB in the high-rises. The partitioning in the field samples were in agreement with the results from the exposure experiment and indicate near steady state conditions for the congeners in the dust from the homes. Dust exposed directly on the floorboards showed lower concentrations than samples placed on foil, indicating an ongoing sorption to the varnish being a tertiary source contaminated by the air.For efficient solar energy harvesting, various engineering strategies to strengthen visible-light responsivity of ZnO photocatalyst is under intensive investigation. In this work, a new ternary C-ZnO/MoS2/mesoporous carbon nanocomposite was successfully prepared by a two-step solution-processed synthesis protocol. The ternary composite exhibits a well-interconnected 3D mesoporous microstructure assembled by carbon nanosheets, which is loaded with quasi 0D ZnO nanoparticles and 2D MoS2 nanosheets. The carbonaceous nanocomposites show enhanced visible-light-driven photocatalytic performance and high photo-corrosion resistance. The incorporation of carbon in the hybrid design has manifold benefits that drastically promotes the photoactivity and photostability. The significant enhancement in photodegradation activity of the hybrid catalysts can be ascribed to a few positive synergistic effects, such as increased surface area and active reaction sites, boosted surface charge utilization efficiency, and band-gap lowering. The high porosity of the distinct microstructure raises the dye adsorption within the material. Tailored interface/surface properties enable more effective mass transport and higher separation efficiency of photo-generated carriers. The modulated electronic structure leads to the narrowing of the ZnO optical bandgap. Meanwhile, coupling with carbon prevents ZnO from photo-corrosion. Our approach highlights the roles of carbon as structure directing and stabilizing agents as well as heteroatom in defect engineering for wide band-gap oxide materials. The rational material design of multivariate mixed-dimensional architecture also provides guiding insight for the advancement of heterogeneous photocatalyst materials with superior performance and durability. The presented engineering strategy would be a promising method for the preparation of nanomaterials supported on 3D carbon network with high porosity and visible-light-driven photocatalytic performance.