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Objective: This study was conducted to describe secondhand smoke (SHS) exposure among non-smoking employees in the workplace, and identify factors related to SHS exposure in Qingdao. Methods: The study participants covered key non-smoking places stipulated in the "Qingdao City Smoking Control Regulations," which included three categories: restaurants, bars, and office buildings. Airborne nicotine concentration in the workplace and saliva cotinine concentration of employees were measured. The questionnaire included employees' demographic factors, smoke-free measures in the workplace, employers' tobacco hazard knowledge, and attitudes towards smoke-free policy. Results: A total of 222 non-smoking employees and 46 non-smoking employers were included in the study. The median concentrations of airborne nicotine and salivary cotinine were 0.389 μg/m3 and 0.575 ng/mL, respectively. Educational status, average number of workplace smokers per day, exposure time to SHS in the workplace, and whether smoking and non-smoking areas were divided significantly related to airborne nicotine concentration. Age, educational status, exposure time to SHS in the workplace, tobacco control training and publicity, and whether the employers support the "Qingdao Tobacco Control Regulation" were significantly related to salivary cotinine concentration. Conclusions: Despite the implementation of the "Qingdao Smoking Control Regulations" in 2013, the workplace remains an important location for SHS exposure. Interventions such as raising workers' awareness of the risks associated with SHS exposure through health education and developing smoking prevention and cessation programs to reduce SHS exposure in the workplace are urgently needed. [ABSTRACT FROM AUTHOR]

Colloids may play an important role in the geochemical cycle of antimony (Sb). However, the controlling behaviors of colloids on Sb fate in contaminated groundwater are not available. To investigate the effects of colloids on Sb mobility, groundwater samples from Xikuangshan Sb Mine's two main aquifers (the D 3 s2 aquifer and the D 3 x4 aquifer) were successively (ultra)filtered through progressively decreasing pore sizes (0.45 µm, 100 kDa, 50 kDa and 5 kDa). The results showed that 0.1–84.1% of Sb was adsorbed or carried by colloids, which corresponded to Sb concentration ranging between 0 and 2973 μg/L in the colloids (0.45 µm - 5 kDa). In both aquifers, Sb was closely associated with organic colloids (r = 0.72 p < 0.05 for the D 3 x4 aquifer, r = 0.94 p < 0.01 for the D 3 s2 aquifer). Parallel factor analysis of the three-dimensional fluorescence spectra determined that the protein-like substances in the D 3 x4 aquifer and the humus-like substances in the D 3 s2 aquifer controlled Sb behavior. X-ray absorption spectroscopy confirmed Sb complexing with organic substances. Competitive adsorption of As and Sb suppressed the complexation of colloids with Sb, particularly in the D 3 x4 aquifer (r = –0.71, p < 0.05). Sb mobility was also influenced by the redox of the groundwater system. As the oxidation-reduction potential and dissolved oxygen increased, Sb in the colloidal fractions decreased. These findings provide new insights into the mechanisms involved in Sb fate affected by colloids, establishing the theoretical basis for developing effective Sb and even metalloid pollution remediation strategies. [Display omitted] • Colloids are important in Sb geochemical cycling. • Colloidal Sb behavior was mainly controlled by organic colloids. • Arsenic competes for Sb adsorption sites on colloids. • Oxidizing conditions reduced the proportion of Sb in colloids. [ABSTRACT FROM AUTHOR]

The dissimilatory Fe(III)-reducing bacteria play a significant role in the mobility of antimony (Sb) under reducing environment. Sb-rich smelting slag is iron (Fe)-containing antimonic mine waste, which is one of the main sources of antimony pollution. In this study, the soluble antimony reacted with Fe(III) by S. oneidensis (Shewanella oneidensis strain MR-1) was performed in reduction condition, then the dissolution behavior of the Sb-rich smelting slag with S. oneidensis was investigated. The results showed that the released Sb was immobilized by S. oneidensis and the strain adsorbed Sb(III) preferentially. Sb(V) can be reduced by S. oneidensis without aqueous Fe. In the presence of Fe(III), S. oneidensis mediated Sb bio-adsorption and the chemical redox of Sb-Fe occurred simultaneously. Sb was co-precipitated with Fe to form the Sb(V)-O-Fe(III) secondary mineral, which was identified as the bidentate mononuclear edge-sharing structure by extended X-ray absorption fine structure (EXAFS) analysis. These results suggest that S. oneidensis has a positive effect on the immobilization and minimizing toxicity of antimony in anoxic soil and groundwater, which provides a theoretical basis for the treatment of antimony contamination. [Display omitted] • Sb was immobilized by S. oneidensis and Sb(III) was bio-adsorbed preferentially. • Sb(III) was indirectly oxidized to Sb(V) by S. oneidensis with aqueous Fe(III). • Sb was co-precipitated with the released Fe from the Sb-rich smelting slag. • Secondary mineral was bidentate mononuclear structure with Sb(V)-O-Fe(III). [ABSTRACT FROM AUTHOR]

A method of Mn-coated biochar production was developed, which showed great removal ability of trivalent antimony (Sb(III)) (0.94 mg g−1) and pentavalent antimony (Sb(V)) (0.73 mg g−1), and the adsorption capacity was stable under different pH. According to the adsorption kinetics and isotherm, the adsorption process of both Sb(III) and Sb(V) was chemisorption, which was both monolayer and poly layers heterogeneous chemisorption process. X-ray photoelectron spectroscopy (XPS) and attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy analyses indicated that the main oxides and functional groups involved in the adsorption were manganese oxides (MnO x), carboxyl and hydroxyl groups and Sb(V) was combined with Mn-coated biochar by inner-sphere complexation. Sb(III) was oxidized by oxygen and MnO x which was both on the surface of biochar and dissolved in solution. Furthermore, X-ray absorption near-edge structure (XANES) showed that Sb(V) was the main species after Sb(III) and Sb(V) adsorbed on the Mn-coated biochar. Extended X-ray absorption fine structure (EXAFS) analysis indicated that Sb(III) and MnO x formed the monodentate mononuclear and corner-sharing complexes with a structure of Mn-O-Sb on Mn-coated biochar. While Sb(V) and MnO x formed inner-sphere complexes including edge-sharing and corner-sharing complexes. The new synthetic material can contribute to develop new remediation strategies for treating Sb-contaminated water. Unlabelled Image • Biochar modified with MnSO 4 is firstly used for Sb removal. • Mn oxides, carboxyl and hydroxyl groups are involved in Sb removal. • Sb(III) is oxidized by oxygen and Mn oxides. • Sb XANES analyses show Sb(V) is the main species after removal. • Sb EXAFS analyses show Sb is in Sb-O-Mn form in Mn-coated biochar. [ABSTRACT FROM AUTHOR]

Background: Mixed results have been found regarding the relationship between media use degree and depressive symptoms. The purpose of this study is to explore the relationship between media use degree, big five personality and depressive symptoms with a mediation model. Method: This was a cross-sectional study. With 9-item Patient Health Questionnaire (PHQ-9), 10-item Big Five Inventory (BFI-10) and self-designed media usage scale, 11,031 participants aged 12 and above in 120 cities in China were collected. Pearson correlation analysis and regression analysis were performed on the data. The Process plug-in was used to construct the mediation model and explore the relationship among media use degree, big five personality and depressive symptoms. The nonparametric percentile Bootstrap method was used to test the mediating effect of personality traits. Results: The degree of media use was positively correlated with depressive symptoms (r = 0.20, P < 0.001), and big five personality played a mediating role between the degree of media use and depressive symptoms. Among five traits, extroversion (r=-0.12, P < 0.001), conscientiousness (r=-0.23, P < 0.001), openness (r=-0.03, P < 0.01) and agreeableness (r=-0.22, P < 0.001) were negatively correlated with depressive symptoms, and neuroticism (r = 0.25, P < 0.001) were positively correlated with depressive symptoms. In addition, extraversion (-0.004, -0.001), conscientiousness (-0.015, -0.008), agreeableness (-0.008, -0.001) and neuroticism (-0.015, -0.007) in big five personality played a mediating role between media use and depressive symptoms. Conclusion: The degree of media use positively predicted depressive symptoms, and excessive media use may bring risks to mental health. People with high neuroticism, low agreeableness, low conscientiousness and low extroversion are more likely to suffer from depressive symptoms. [ABSTRACT FROM AUTHOR]

Smoke-free government(SFG), as a key tobacco control measure, has been added in Healthy China 2030 blueprint and Qingdao started the establishment of the demonstrative SFG in 2020.This study examined the effects of SFG policy on smoking and smoke-free(SF) environment after establishing the demonstrative SFG. This cross-sectional survey selected participants by simple random sampling from party and government agencies in Qingdao (N = 3625) and the participants filled in questionnaires online from November 31 to December 15, 2020. We utilized AMOS to set up models to analyze the direct and indirect effects of SFG policy. The findings showed that knowledge of SFG policy was positively associated with SF environment(β = 0.29, P<0.001) and negatively associated with smoking(β = -0.14,P<0.001). Knowledge of SFG policy had indirect effects on SF environment through four channels: independent mediation of discouraging smoking and attitude towards SFG policy, as well as chain mediation of these two factors, and perception of tobacco hazards and discouraging smoking, with indirect effects accounting for 33.5% of the total effect. Knowledge of SFG policy had indirect effects on smoking reduction via SF environment and two chain mediation: SF environment and attitude towards SFG policy, perception of tobacco hazards and intention to quit smoking, with indirect effects accounting for 50.2% of the total effect. The results provided the evidence that SFG policy not only had positive effects on creating SF environment but also on reducing smoking. The efficient policy infiltration to individuals played a vital role in the establishment of SFG. Attitude towards SFG policy, discouraging smoking and SF environment were the potential mediators for SFG policy. Findings in this study added more evidence related to effect mechanism of SFG policy and had a positive influence on promoting the implementation SFG policies for China and other countries. [ABSTRACT FROM AUTHOR]

The Xikuangshan (XKS) mine, an antimony mine that has been active for more than a century, was chosen for a detailed antimony hydrogeochemical study because of the historical antimony contamination in local bedrock aquifers. Hydrochemical data, δ34S values of dissolved SO 4 2−, and δ98Mo values were analyzed to identify the predominant geochemical processes affecting Sb attenuation within the aquifers. Groundwater from the adits at the XKS Sb mine reflects an oxidizing environment and has pH values between 6.81 and 8.89 because of the sufficient acid-neutralizing effect of carbonates. The decrease in Sb concentrations along the groundwater flow direction and the highly coloured deposits in the adits indicate Fe and Mn oxides have a significant capacity for Sb sorption. The δ34S values of the groundwater indicate that reductive dissolution of Fe(III) hydroxides is not the dominant process controlling Sb mobilization. Furthermore, the δ34S values and weak-alkaline groundwater corporately suggest that Sb adsorption on and desorption from Fe/Mn (hydr)oxides may both occur, with adsorption being more significant than desorption with respect to Sb attenuation in groundwater. The δ98Mo values of the groundwater further demonstrate that this adsorption is relatively significant in terms of Sb attenuation, and that competitive adsorption may occur between Sb and As in groundwater at the XKS Sb mine. Overall, the hydrochemistry analysis, especially the S and Mo isotope evidences collectively elucidate that the attenuation of Sb in groundwater from the XKS Sb mine are influenced by several geochemical processes, including: (1) more adsorption on than desorption from Fe/Mn (hydr)oxides; (2) competitive adsorption of arsenic; and (3) dilution with low-Sb groundwaters. This study demonstrates that hydrochemical analyses, particularly S and Mo isotope studies, are useful for tracking Sb attenuation in groundwater from antimony-contaminated mine areas. [Display omitted] • S and Mo isotopes were used to elucidate the attenuation of Sb in bedrock aquifer. • Adsorption on Fe/Mn (hydr)oxides is relatively significant in terms of Sb attenuation. • A competitive adsorption may occur between Sb and As. • A conceptual model of Sb attenuation in bedrock aquifer system was proposed. [ABSTRACT FROM AUTHOR]

The Xikuangshan (XKS) mine, the world's largest antimony (Sb) mine, was chosen for a detailed Sb isotopic signature study owing to its historical Sb contamination of water systems. Hydrochemical data, in particularδ123Sb values, were analyzed to identify the Sb source and predominant geochemical processes that affect Sb mobilization in different waters. The δ123Sb values of waters from the XKS Sb mine range from − 0.20‰ to + 0.73‰. In particular, the δ123Sb values of the main Feishuiyan stream do not significantly vary (+0.19‰-+0.24‰), while those of groundwater in different aquifers (−0.08‰ to +0.73‰) and mine water in different adits (−0.20‰ to +0.37‰) vary over a wide range. The relationships between δ123Sb values and Sb concentrations indicate that a simple dilution of Sb and a weak Sb adsorption onto Fe/Mn suspended particles and sediments in the Feishuiyan stream may occur, oxidative weathering and leaching infiltration of Sb-containing waste rocks and slags may cause variations in the δ123Sb values in groundwater, and Sb mobilization in the mine water is influenced by a combination of processes (oxidative dissolution, adsorption of Fe/Mn (hydr)oxides, and mixing). A conceptual hydrogeochemical model was summarized to elucidate the Sb source and mobilization in water systems from the XKS Sb mine. [Display omitted] • The δ123Sb values of waters from the XKS Sb mine range from − 0.2‰ to + 0.73‰. • Both adsorption onto Fe/Mn (hydr)oxides and mixing occur in mine water. • The source and mobilization of Sb are closely related to the mining activities. • A conceptual model of Sb source and mobilization in water systems was proposed. [ABSTRACT FROM AUTHOR]