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This review will provide a scientific reference for Cd pollution control and management with respect to paddy field ecosystems in China and other countries.Heavy metal contamination has been threatening the health of human beings. To decrease the bio-toxicity of heavy metals, a thiol-functionalized nano-silica (SiO2-SH) was adopted to remediate the soil contaminated by lead (Pb), cadmium (Cd) and copper (Cu). The remediation effect of SiO2-SH on contaminated soils was investigated by the uptake of the heavy metals into lettuce and pakchoi in pot experiment. The bio-toxicity of the SiO2-SH was evaluated, and its immobilization mechanisms were proposed by the fraction distribution of Cd, Pb and Cu. It was found that the SiO2-SH can significantly reduce the uptake of Cd, Pb, Cu into pakchoi by 92.02%, 68.03%, 76.34% and into lettuce by 89.81%, 43.41%, 5.76%, respectively. The chemical species analyses of Cd, Pb, Cu indicate SiO2-SH can transform the heavy metal in acid soluble states into reducible fraction and oxidizable fraction, thereby inhibiting the extraction of heavy metals into soil solution. The concentrations of microbial biomass carbon, organic matter, and cation exchange capacity of the soil increased while the soil bulk density decreased after remediation. Those changes demonstrate that SiO2-SH not only has no bio-toxic impact on the soil environment but also improves the soil environment, which proves the prepared SiO2-SH is environmental-friendly. The SiO2-SH could be a promising amendment for heavy metal contaminated soils.Pyriproxyfen is a juvenile hormone analogue insecticide used worldwide. At present, the potential threat of pyriproxyfen to aquatic organism has not been well explored. In this work, the bioaccumulation, metabolic profile and toxicity of pyriproxyfen and its metabolites to zebrafish were studied, and the enantioselectivity of pyriproxyfen and the major chiral metabolites were also determined. Sixteen metabolites of pyriproxyfen in zebrafish were identified. Hydroxylation, ether linkage cleavage and oxidation in phase I metabolism, followed by sulfate and glucuronic acid conjugation. The bioconcentration factors ranged from 1175 to 1246. Hydroxylation metabolites of pyriproxyfen showed enantioselective behavior in zebrafish with enantiomer fractions (EFs) of 4′-OH- pyriproxyfen and 5″-OH- pyriproxyfen ranged from 0.50 to 0.71. Toxicological indexes including acute toxicity, joint toxicity and oxidative stress were tested. Among all the metabolites, 4′-OH- pyriproxyfen was found 2 folds more toxic to zebrafish than pyriproxyfen. (-)-Pyriproxyfen was found 2 folds more toxic than rac- and (+)-pyriproxyfen. Antagonistic effects were found in binary joint toxicity of pyriproxyfen and its hydroxylated metabolites. Pyriproxyfen and its metabolites also showed oxidative stress damage by inhibiting the activity of CAT and SOD and increasing MDA. This work provided deep insight into the metabolism and the potential risks of pyriproxyfen to aquatic organisms.Trace organic compounds (TOrCs) and microplastics (MPs) have been recognized as emerging pollutants that cause severe water pollution related problems due to their non-degradable and bio-accumulative nature. Many studies on oxidation processes such as ozone have been conducted to efficiently remove TOrCs in water treatment. However, there has been a lack of research on the removal efficiency of TOrCs in the oxidation process when they co-exist with MPs and form transformation byproducts (TBPs) during this process. This study evaluates the effects of MPs on TOrC removal during ozonation at various ozone concentrations and based on the mass of MP particles in distilled water. The adsorption of TBPs and TOrCs was also evaluated using the Freundlich and Langmuir isotherm equations. The toxicity of these compounds was evaluated to confirm the risk to aquatic ecosystems. TD-139 price The results show that triclosan (TCS) had the highest absorption capacity amongst the TOrCs and TBPs tested. Polyvinylchloride exhibited the highest adsorption efficiency compared with polyethylene and polyethyleneterephthalate (TCS 0.341 mg/g) due to its high adsorption capacity and hydrophobicity. In the toxicity test, 2,4-dichlorophenol and 4-chloroaniline as TBPs had a relatively higher toxicity to Vibrio fischeri (a marine bacterial species) than Daphnia magna (a freshwater plankton species).Particulate matter 2.5 (PM2.5) is an inflammatory-inducing factor that is considered to be related to many adverse respiratory problems, especially in the elderly. This study aimed to examine whether pre-exercise training could prevent pulmonary injury induced by urban PM2.5 in aging rats and investigate its relationship with inflammatory pathways. Male Wistar rats (aged 16 months) were randomly divided into four groups sedentary, exercise, sedentary + PM2.5 exposure, and exercise + PM2.5 exposure. All rats in exercise-related groups were treadmill-trained for 8 weeks (65%-75% VO2max for 30 min every other day). Sedentary groups’ rats lived freely in cages without exercise intervention. Rats in the PM-related groups were exposed to ambient PM2.5 (4 h day-1) for 2 weeks after an 8-week exercise intervention or sedentary treatment. Finally, all rats’ pulmonary function, lung morphology, degree of inflammation, and relevant protein and mRNA transcript expression levels were examined. The results indicated that Percise training may be an effective way to protect against PM2.5-induced lung toxicity in aging individuals.Urban street canyons formed by high-rise buildings restrict the dispersion of vehicle emissions, which pose severe health risks to the public by aggravating roadside air quality. However, this issue is often overlooked in city planning. This paper reviews the mechanisms controlling vehicle emission dispersion in urban street canyons and the strategies for managing roadside air pollution. Studies have shown that air pollution hotspots are not all attributed to heavy traffic and proper urban design can mitigate air pollution. The key factors include traffic conditions, canyon geometry, weather conditions and chemical reactions. Two categories of mitigation strategies are identified, namely traffic interventions and city planning. Popular traffic interventions for street canyons include low emission zones and congestion charges which can moderately improve roadside air quality. In comparison, city planning in terms of building geometry can significantly promote pollutant dispersion in street canyons. General design guidelines, such as lower canyon aspect ratio, alignment between streets and prevailing winds, non-uniform building heights and ground-level building porosity, may be encompassed in new development.