Samples of water, sediment and epilithic periphyton (EP) were collected from a lake (Dimna, DL), an intermediate canal (IC), and a river (Subarnarekha River, SR) to compare the pollution status of an urban ecosystem, and the concentrations of metal(loid) s were determined. Water characteristics were analysed by the water quality index (WQI). Sediment pollution was assessed using the ecological risk index (ERI). Accumulation of metal(loid) s in EP was determined by using bioaccumulation factor (BAF) and biota-sediment accumulation factor (BSAF). The result showed that the DL was least polluted (WQI = 30.39) and SR (WQI = 90.13) was the most polluted ecosystem. Sediment analysis revealed that Ni, Cr and Cd are the significant pollutants, especially in SR. The THQ value for fish dishes cooked in Indian style was found higher than that of raw fish, suggesting calculations considering the cooking process can provide better results. Health risk assessment shows that people inhabiting DL are vulnerable to Cr and Cu exposure, whereas people inhabiting IC and SR are susceptible to As and Co exposure due to the consumption of cooked fish. Moreover, for a developing country like India, it is important to upgrade the assessment methods and include regular monitoring of interconnecting ecosystems for the safeguard of human and ecological health.

The soil microbiome comprises one of the most important and complex components of all terrestrial ecosystems as it harbors millions of microbes including bacteria, fungi, archaea, viruses, and protozoa. Together, these microbes and environmental factors contribute to shaping the soil microbiome, both spatially and temporally. Recent advances in genomic and metagenomic analyses have enabled a more comprehensive elucidation of the soil microbiome. However, most studies have described major modulators such as fungi and bacteria while overlooking other soil microbes. This review encompasses all known microbes that may exist in a particular soil microbiome by describing their occurrence, abundance, diversity, distribution, communication, and functions. Finally, we examined the role of several abiotic factors involved in the shaping of the soil microbiome.

Brominated flame retardants (BFRs) are commonly used in consumer products and they shed off these products and eventually build up in household dust. Polybrominated diphenyl ethers (PBDEs), in particular, are known endocrine-disrupting chemicals affecting various hormone syntheses. Portable X-ray fluorescence spectroscopy (XRF) is the most common non-destructive method in identifying BFRs in environmental samples. However, the method is insensitive to bromine speciation. Synchrotron-based XRF has been shown to have very low detection limits (< 1 μg/g) that is suitable for detecting BFRs and can be combined with X-ray absorption near-edge spectroscopy (XANES) to identify the bromine species present in the household dust. Twenty indoor dust samples were collected from rural homes in Newfoundland (Canada) to assess the use of synchrotron-based techniques to identify BFRs. Synchrotron-based XRF analysis identified bromine in all the samples, with concentrations ranging from 2–19 μg/g. XANES analysis identified organic-based bromine species in several samples that are likely BFRs based on the spectral line shape. The accuracy of using XANES to identify BFRs is highly dependent on the source and size of the dust samples. Therefore, for future research, it is important to take into account the sources of dust sample and to focus on fine dust particles.

The heavy metal sources of large-scale raceway pond microalgae cultivation with flue gas were investigated to reduce heavy metal contents in microalgae during cultivation. The microalgae were cultivated with power plant flue gas (as C source) and circulating cooling seawater (added with N and P nutrients) for 6 days. The Pb, Cd, Hg, and As contents in microalgae were 0.91, 0.22, 0.08, and 0.28 ppm, respectively, which are nearly within the available national standard for food-grade microalgae. The heavy metal contents in microalgae with two membrane materials, namely, elastic polyethylene and random copolymer polypropylene, barely increased. The Hg, As, and Pb contents in microalgae cells cultivated with pure CO₂ were 16.67%, 69.23%, and 70.33% that of cells cultivated with CO₂ from flue gas. The Pb, As, and Hg contents in cells cultivated with fresh water were reduced by 38.46%, 15.38%, and 37.50%, respectively, compared with those cultivated with seawater. The heavy metal contents in microalgae were further reduced and controlled.

For the purpose of enhancing the removal rate of nitrogen (N) and organic matters, intermittent aeration and carbon source were used in filled-and-drained vertical flow constructed wetlands (VFCWs). The results showed that the best removal of COD (74.16%), NH₄⁺-N (93.56%), TN (86.88%), and NO₃⁻-N (79.65%) was achieved in VFCW1 (aerated with carbon source system). Illumina MiSeq300 high-throughput sequencing showed that carbon source aerated system increases the diversity and richness of the microbial community. The copy numbers of nitrification functional genes (nxrA, amoA), denitrification functional genes (nirS, nirK, nosZ), and anammox functional gene (anammox 16S rRNA) displayed various changes when applied different aeration modes and additional carbon source to each system. An increase of the DO concentration and carbon source facilitated the absolute abundance of microbial nitrification and denitrification functional genes, respectively. All in all, these results demonstrate that carbon source combined with intermittent aeration is valid to improve the pollutant treatment performance in these systems.

The China-Pakistan Economic Corridor (CPEC) is a journey towards economic integration of Eurasia. The CPEC contains US$62 billion investment projects on energy, infrastructure, and other development projects in Pakistan. However, CPEC could enhance climate change vulnerabilities for the faltering economy of Pakistan due to its three possible environmental risks and repercussions. Its major environmental concern is related to energy projects as three quarters of the newly planned energy will be generated from traditional coal-fired power plants. Traditional coal power plants are the major contributors to CO₂ emissions and smog, which ultimately lead to global warming and climate change. Its second important environmental concern is linked with massive tree cutting for the construction of various road networks from Kashghar, China, to Gwadar, Pakistan. Tree cutting leads to enormous concentration of CO₂ emissions along the road networks. Vehicle trafficking is its third important environmental threat. Karakorum highway is expected to carry up to 7000 trucks per day that will release up to 36.5 million tons of CO₂. Despite all the environmental risks, the CPEC enables Pakistan to manage energy crisis and upgrade aging infrastructure. However, if appropriate remedial measures are not taken to diminish environmental risks, Pakistan will be among major contributors to CO₂ emissions, and its rank will be worsen in global climate risk index, after completion of this project. Therefore, it is very crucial to assess possible environmental impacts of CPEC projects regarding energy, infrastructure, and transportation. Furthermore, scientists from both countries should collaborate to manage the environmental repercussions of CPEC projects.

A novel adsorbent derived from banyan aerial roots was prepared via modification and employed to aqueous gentian violet (GV) and rhodamine B (RhB) removal. The surface morphology and physicochemical properties of modified banyan aerial roots (MBARs) were investigated by SEM, EDS, N₂ adsorption/desorption, zeta potential, XRD, and FT-IR characterization experiments. Adsorption factors were tested, and the optimal conditions for GV and RhB removal were pH of 6 and 3, doses of 0.02 g and 0.03 g, and reaction time of 540 min. Adsorption isotherm simulation illustrated that theoretical monolayer adsorption capacities of GV and RhB were 456.64 mg/g and 115.23 mg/g, respectively. Kinetics data was assessed with pseudo-first-order and pseudo-second-order models, and the latter described GV and RhB adsorption better at 288 K, 298 K, 308 K, and 318 K. Thermodynamic analysis indicated that GV and RhB adsorption processes were endothermic and spontaneous. From the research results, it could be inferred that GV adsorption was mainly dominated by electrostatic interaction, while RhB adsorption might be primarily attributed to electrostatic interaction and hydrogen bonding. The study based on full utilization of waste plant fibers facilitates recycling of biomass resources, and due to simplicity, safety, and eco-friendliness of the preparation, as well as low cost and high efficiency of the application, MBARs may be potential absorbents for the treatment of dyestuff wastewater.

The degradation of land by trace metals contamination around coal mining areas is a serious environmental issue, and therefore, it is necessary to have detailed information about the pollution caused by them and their sources. The objective of the work was to study the impact of trace metals (e.g., Cd, Co, Ni, Cr, Zn, Pb, and Cu) on the soil of Jharia coalfield to analyze their sources, contamination level, and their spatial distribution. The present values of the trace metals were compared by their natural background values which were then analyzed on the scale of the Potential Ecological Risk Index (PERI) and by Improved Nemerow Index (Lₙₘ). The results of spatial distribution revealed that the majority of the soil in Jharia coalfield is moderately contaminated, a small portion of it is slightly contaminated, and altogether at moderate ecological risk due to trace metals. Multivariate statistical techniques including Principal component analysis, Cluster analysis, and Pearson’s correlation evaluated that Cu, Ni, Zn, Co, and Cr in the soil samples had the same source which is coal mining; Pb and Cd were from multiple sources. The spatial distribution maps of trace metals present in the soil of Jharia coalfield were generated using Radial basis function an interpolation method.

This study assessed the effect of rinsing and boiling on total content of As (tAs) and of its inorganic and organic forms in different types of rice (polished and brown) from Spain and Ecuador. Rice was subjected to five different treatments. The results showed that the treatment consisting of three grain rinsing cycles followed by boiling in excess water showed a significant decrease in tAs content compared with raw rice. Regarding As species, it is worth noting that the different treatments significantly reduced the content of the most toxic forms of As. The estimated lifetime health risks indicate that pre-rinsing alone can reduce the risk by 50%, while combining it with discarding excess water can reduce the risk by 83%; therefore, the latter would be the preferable method.

The problem of haze pollution in China is still serious, and it is an important issue how to measure and improve environmental regulation efficiency of haze control (EREHC) in China. To explore the spatial evolution characteristics and influencing factors of EREHC in each province in China, this paper builds an evaluation system for EREHC in China and calculates EREHC values in 30 provinces, autonomous regions, and municipalities in China from 2003 to 2015 through the super-efficiency slacks-based measure (SE-SBM) model. Moreover, the influencing factors and the driving mechanism of EREHC in China are examined by using the Theil index, Moran’s I index, and the geographically and temporally weighted regression (GTWR) model. The results are as follows. (1) During the sample period, EREHC in each province in China is mostly favorable, and the average efficiency value is approximately 0.5. EREHC has been declining only in some regions in China. (2) EREHC in eastern China is the best, followed by western China, and EREHC in central China is the lowest. The inter-regional difference in EREHC has been declining over time. (3) EREHC is positively correlated with economic level, the industrial upgrading, and the opening to the outside world, but negatively correlated with energy mix and labor force quality. The positive and negative effects of the level of scientific and technological input are different among the three economic regions. The results indicate that EREHC in China is generally at low level, which presents the spatial difference characteristic of “High East and Low West.” It will help improve regional EREHC to raise the level of regional economic development, deepen industrial upgrading, and open to the outside world.