Modeling primary and secondary fractionation effects and atmospheric transport of polychlorinated biphenyls through single-source emissions

The Chinese Gridded Industrial Pollutants Emission and Residue Model (ChnGIPERM) was used to investigate potential fractionation effects and atmospheric transport of polychlorinated biphenyls (PCBs) derived from single-source emissions in China. Modeling the indicative PCBs (CB28, CB101, CB153, and CB180) revealed spatiotemporal trends in atmospheric transport, gas/particle partitioning, and primary and secondary fractionation effects. These included the inference that the Westerlies and East Asian monsoons affect atmospheric transport patterns of PCBs by influencing the atmospheric transport time (ATT). In this study, dispersion pathways with long ATTs in winter tended to have short ones in summer and vice versa. The modeled partitioning of PCB congeners between gas and particles was mainly controlled by temperature, which can further influence the ATT. The potential for primary and secondary fractionation was explored by means of numerical simulations with single-source emissions. Within ChnGIPERM, these phenomena were mainly controlled by the temperature and soil organic carbon content. The secondary fractionation of PCBs is a slow process, with model results suggesting a timescale of several decades.

     

Phosphorus adsorption by sediment considering mineral composition and environmental factors

Environmental Science and Pollution Research - Sediment, composed of a complex assemblage of minerals, controls the fate and behaviour of P in aqueous environments and affects trophic status. In...     

Influence of Cd on atrazine degradation and the formation of three primary metabolites in water under the combined pollution

Environmental Science and Pollution Research - To understand the influence of Cd on atrazine (ATZ) degradation in aqueous solution, the degradation of different initial levels of ATZ (0.1, 0.5,...     

Correction to: Knowledge domain and emerging trends of carbon footprint in the field of climate change and energy use: a bibliometric analysis

Environmental Science and Pollution Research -     

Efficient activation of peroxymonosulfate by Co-doped mesoporous CeO2 nanorods as a heterogeneous catalyst for phenol oxidation

Environmental Science and Pollution Research - Sulfate radical?based advanced oxidation processes have received considerable attentions in the remediation of organic pollutants due to their...     

氧化-絮凝深度处理焦化废水的研究

采用氧化-絮凝工艺对焦化废水二沉池出水进行深度处理,选择针对焦化废水研发的M180作为絮凝剂,NaQO作为氧化剂,考察了药剂投加量和废水pH值对处理效果的影响,得出最佳处理条件为:氧化时废水pH为4,氧化剂NaClO的投加量为0.9g/L;絮凝时pH为7,絮凝剂M180的投加量为0.05 g/L.处理后出水COD由160.8 mg/L降至56.9 mg/L,色度为20倍,浊度为0.5 NTU,满足《钢铁工业水污染物排放标准》(GB13456-1992)一级排放标准.     

Numerical simulation of flue gas desulfurization characteristics in CFB with bypass ducts

A new process of flue gas desulfurization in circulating fluidized bed with flue gas bypass ducts is presented. k–? Model, Discrete Phase Model and Finite-Rate Chemistry Model are proposed to simulate the desulfurization process characteristics in circulating fluidized bed reactor. The proposed model is validated by the comparison of experimental data and simulation results. The results show that the desulfurization reactor with bypass ducts is superior to the reactor without bypass ducts. The reactor with bypass ducts has higher desulfurization efficiencies and lower flow resistances than the reactor without bypass ducts, and it is more suitable for flue gas flow variation. Desulfurization reaction rate is controlled by absorption reaction on sorbent particles surface. When water content and Ca/S ratio increase, desulfurization efficiency of the reactor with bypass ducts increases. When SO₂ concentration increases, desulfurization efficiency decreases.     

The antiestrogen-like activity and reproductive toxicity of 2,6-DCBQ on female zebrafish upon sub-chronic exposure

2,6-Dichloro-1,4-benzoquinone (2,6-DCBQ), an emerging water disinfection by-product, is widely detected in water resources. However, its potential effects on the reproductive system are largely unknown. Here, we investigated the long-term effects of 2,6-DCBQ on gonadal development by exposing zebrafish from 15 to 180 days postfertilization (dpf). Following exposure to 2,6-DCBQ (20 and 100 µg/L), female-specific effects including delayed puberty onset, retarded ovarian growth and breakdown of the zona radiata were observed, resulting in subfertility in adult females. Adverse effects in folliculogenesis disappeared two months after cessation of 2,6-DCBQ administration. In contrast, no adverse impacts were noted in male testes. The effects on females were associated with significant reduction in 17β-estradiol (E2) level, suggesting a role for 2,6-DCBQ in anti-estrogenic activity. E2 level change in blood was further supported by dysregulated expression of genes (cyp19a1a, fshb, kiss3, esr2b, vtg1, and vtg3) related to the hypothalamic-pituitary-gonad-liver (HPGL) axis. The present study demonstrates for the first time that 2,6-DCBQ induces reproductive impairments in female zebrafish through disrupting 17β-estradiol level.     

Understanding the excretion rates of methylmercury and inorganic mercury from human body via hair and fingernails

Effective biomarkers are necessary to better understand the human mercury (Hg) exposure levels. However, mismatched biomarker sampling method causes extra uncertainty in assessing the risk of Hg exposure. To compare the differences between hair and fingernail, and further understand the excretion rates of methylmercury (MeHg) and inorganic mercury (IHg) via hair and fingernails, the total mercury (THg), MeHg, and IHg concentrations in paired hair and fingernail samples were investigated through paired samples collected from two typical mining areas, Wanshan mercury mine area (WMMA) and Hezhang zinc smelting area (HZSA). The positive correlation in THg, MeHg, and IHg concentrations (p <0.01) between hair and fingernail samples indicated that those two biomarkers can be corrected in application of assessing human Hg exposure. Compared to fingernails, the hair was suggested to be a more sensitive biomarker as the concentration of THg, MeHg and IHg were 2 ∼ 4 times higher than those in fingernails. Furthermore, the amounts of THg, MeHg, and IHg excreted via hair were 70 ∼ 226 times higher than that excreted via fingernails, and the hair plays a more important role than fingernails in the excretion of Hg from human bodies. Present study therefore provides some new insights to better understand the fate of human assimilated Hg.     

Regional differential decomposition and convergence of rural green development efficiency: evidence from China

Environmental Science and Pollution Research - An objective understanding of the current situation and influencing factors of rural green development in China is an important prerequisite for...