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Little is known about the relationship between traffic congestion and antimony (Sb) distribution in street dust, which is essential for Sb control and emission reduction in urban areas. Sb concentrations and mass load of the street dust collected in 19 cities of China were determined before investigating the mechanism of traffic influence on Sb distribution through diverse statistical means. The results showed that the Sb concentrations in each city were 1.10–4.76 times higher than the local background values. Sb concentrations in transportation areas were significantly higher than those in residential and industrial areas, and were significantly affected by road network density. The effect of congestion on Sb load of street dust was influenced by vehicle flowrate. Only when the vehicle flowrate was high, the traffic congestion would promote the increase of Sb load obviously. The improved accounting method showed that the Sb dissipation from brake wear in major Chinese cities were higher than that in Stockholm, Sweden, in 2005. The latent path analysis illustrated that a 1% increase in congestion index was correlated with a 0.886% increase in the Sb load. Compared with Switzerland, which has a typical industrialized Sb consumption pattern, China needs to recycle brake pads in addition to taking various measures to alleviate traffic congestion and reduce brake pad wear, despite the fact that the maximum health risk of Sb was far below the safety threshold. This study will provide valuable insights for urban traffic management and brake pad recycling. [Display omitted] • The effect of congestion index on Sb load of street dust was influenced by vehicle flowrate. • Material flow analysis for Sb dissipation from brake wear was improved pursuant to congestion. • The latent path analysis quantified the relationship between traffic congestion and Sb load. [ABSTRACT FROM AUTHOR]

Co 3 O 4 @rGO were facilely prepared by template free self-assemble in this study. The morphology of Co 3 O 4 @rGO was actiniaria-like core-shell structural nanocomposites. The formation mechanism of Co 3 O 4 @rGO core-shell nanocomposite was discussed according to its significant time-dependent morphology evolution course. To evaluate the application potential of Co 3 O 4 @rGO, its adsorption performance toward highly toxic antimony ions were studied. The Co 3 O 4 @rGO nanocomposite exhibit high anti-interference ability and high adsorption ability. The maximum adsorption capacities towards Sb(III) and Sb(V) are 151.04 and 165.51 mg/g, respectively. River water samples containing antimony violating the limit were used to evaluate the practical application of Co 3 O 4 @rGO, and high performance was achieved. The EU and China limits for antimony in drinking water can be met by using mesoporous Co 3 O 4 @rGO treating the actual river water samples with original antimony concentration lower than 50 μg/L. Adsorption isotherm, adsorption kinetics, pH and co-existing ions effects were also studied in details. The results indicate that mesoporous Co 3 O 4 @rGO is an excellent adsorbent for antimony removal. Mesoporous Co 3 O 4 @rGO nanocomposite is a potential candidate for antimony removal from waste water. Image 1 • High performance core-shell structure Co 3 O 4 @rGO nanocomposites were synthesized. • The actiniaria-like core-shell structure was self-assembled without template. • The time-dependant self-assembling process was detailly investigated. • Co 3 O 4 @rGO exhibits high antimony removal performance by adsorption. • The different adsorption mechanisms for Sb(III) and Sb(V) were discussed in details. [ABSTRACT FROM AUTHOR]

Thallium (Tl) is an uncommon toxic element, with an even greater toxicity than that of As, Hg and Cd. Steel-making industry has been identified as an emerging new significant source of Tl contamination in China. This paper presents a pilot investigation of the contamination and geochemical transfer of Tl and associated metal(loid)s in river sediments affected by long-term waste discharge from the steel-making industry. The results uncovered an overall Tl contamination (1.96 ± 0.42 mg/kg) across a sediment profile of approximately 1.5 m in length, even 10 km downstream the steel plant. Highly elevated contents of Pb, Cu, Cd, Zn and Sb were found in the fluvial sediments, displaying strong positive correlations with Tl contents. Elevated levels of geochemically mobile Tl as well as Cd, Zn, Cu and Pb occurred in the fluvial sediments, signifying anthropogenic imprints from steel production activities at high temperature. Levels of contamination and ecological risk were calculated to be moderate to considerable for Tl, Cu, Zn and high to very high for Cd, Pb, Sb. The results highlight that there is a great challenge in view of potentially considerable Tl pollution due to continuous massive steel production in many other parts of China. It is high time to initiate process-based management of Tl contamination control for the ambient aquifer system in the steel-making area. Image 1 • Steel industry is an emerging new significant source of Tl pollution in China. • Steel-making activities have generated Tl contamination imprints in river sediments. • High levels of Tl as well as Pb, Zn, Cd, and Sb were identified in the sediments. • Higher than 30% of Tl is geochemically mobile, bearing high ecological risks. • It indicates great challenge for Tl pollution in China due to massive steel industry. [ABSTRACT FROM AUTHOR]