摘要:
Burning municipal waste produces a great deal of harmful heavy metals, which may lead to elevated exposure in incinerator workers and residents living nearby. However, relevant human exposure studies remain scarce, especially in China. This study aimed to determine the concentrations of ten heavy metals in urine of incinerator workers (n = 119, as the exposed group) and residents living nearby (n = 215, as the control group) from Shenzhen (China), and explore the associations between heavy metal exposure and DNA oxidative stress (indicated by 8-hydroxy-2'-deoxyguanosine or 8-OHdG) in humans. The median urinary concentrations of manganese (Mn), iron (Fe), chromium (Cr), arsenic (As), selenium (Se) and 8-OHdG in the exposed group were significantly higher than those in the control group (p < 0.05), suggesting occupational exposure elevated heavy metal intake for the incinerator workers. Nevertheless, there is no correlation statistically significant between the concentrations of any heavy metal and 8-OHdG in urine in the exposed group, indicating heavy metals releasing from waste incineration were not important factors to induce DNA oxidative stress. To our knowledge, this study firstly reported the concentrations of heavy metal in urine and their associations with DNA oxidative damage in waste incinerator workers in Shenzhen, China. (C) 2020 Elsevier Ltd. All rights reserved.
摘要:
The adsorption characteristics of phosphorylated Aspergillus niger (AN-P) for uranium(VI) were studied in this work. The AN-P was successfully prepared by the reaction of Aspergillus niger with phosphorus pentoxide in ice-bath under the catalysis of methanesulphonic acid. AN-P was characterized by FT-IR and SEM-EDS. The effects of pH, contact time, initial U(VI) ions concentration, adsorbent dosage and temperature on the adsorption of U(VI) by AN-P were investigated. The isotherm and kinetic data were accurately described by the Langmuir and pseudo-second-order models, respectively. The calculated thermodynamic parameters indicated that the adsorption of U(VI) by AN-P was an spontaneous and endothermic process. This indicated that the AN-P composite is a promising adsorbent for efficient removal of U(VI) from radioactive wastewater.
摘要:
A biosorbent, 4-sulfonylcalix[6]arene modified Fe(3)O(4)@Aspergillus Niger (MFSC), was successfully prepared through a two-step route for the effective removal of uranium (U(VI)) from aqueous solutions with high selectivity. The structure of MFSC was characterized by FT-IR, SEM, XRD, TGA and VSM, respectively. The impacts of various experimental parameters were investigated in detail. The results indicated that the biosorption of U(VI) on MFSC was mainly attributed to the electrostatic attraction (91% within 8 hours for U(VI)). The adsorption kinetics and adsorption isotherm of U(VI) were found to follow the pseudo second-order model and to be fitted by the Langmuir model, respectively. The thermodynamic parameters revealed that the adsorption process was spontaneous and endothermic. The findings herein highlight the MFSC with high ability for removal of U(VI) from aqueous solutions.
摘要:
The Aspergillus niger magnetic bioadsorbent ANFAN (amidoxime modified Nano-Fe3O4-Aspergillus niger, ANFAN) was prepared by amine oximation reaction with Aspergillus niger and nano-Fe3O4. The effects of initial pH value, adsorption time, adsorbent dosage, initial uranium concentration and coexisting ions on the adsorption of ANFAN for uranyl ion were studied in detail. The results showed that under the optimum adsorption conditions, the maximum adsorption efficiency of ANFAN for U(VI) solution amounted to 92.35%, and the maximum biosorption capacity could reach 23.38 mg/g. The kinetic data followed the pseudo-second-order model which indicated that the adsorption for uranium was mainly chemical activity on the surface of ANFAN. The adsorption equilibrium data fitted the Langmuir isotherm model well, which indicated that the adsorption of ANFAN for uranium was a single layer of chemical adsorption. Adsorption thermodynamics studies indicated that adsorption of ANFAN for uranium was a viable, spontaneous and endothermic process. The study provided a novel magnetic biosorbent with high adsorption capacity and a new method of adsorption for low concentrations of uranium.
摘要:
This work describes a method for the determination of 1-hydroxypyrene (OH-Py) via aggregation-induced quenching of the emission of protamine-coated gold nanoclusters using 9-hydroxyphenanthrene (OH-Phe) as a sensitizer to boost the emission efficiency of nanoprobe. Under optimum conditions, the drop in fluorescence intensity at excitation/emission wavelengths of 300/596 nm is proportional to the concentrations of OH-Py in the range from 1.0 to 65 nM. The relative standard deviations are 4.2, 2.4 and 1.9% (for n = 11) at concentration levels of 8.0, 32 and 48 nM of OH-Py, respectively. The detection limit is 0.3 nM which is much lower than that of some previously reported methods. The recoveries from urine samples spiked with OH-Py ranged between 94.4 and 98.8%. Graphical abstract 1-Hydroxypyrene (OH-Py) can trigger the aggregation of protamine-gold nanoclusters (PRT-AuNCs), resulting in the emission quenching of PRT-AuNCs. 9-Hydroxyphenanthrene (OH-Phe) can boost the emission efficiency of nanoprobe. Thereby, a highly sensitive assay of OH-Py was established.
期刊:
Journal of Radioanalytical and Nuclear Chemistry,2018年316(1):331-339 ISSN:0236-5731
通讯作者:
Li, Le
作者机构:
[Tan, Yan; Cheng, Bin; Lu, Wei; Li, Le] Univ South China, Sch Publ Hlth, Hengyang 421001, Peoples R China.;[Tan, Yan; Cheng, Bin; Lu, Wei; Li, Le; Dai, Zhongran; Liao, Qi; Sun, Jing] Univ South China, Hunan Prov Key Lab Green Dev Technol Extremely Lo, Hengyang 421001, Peoples R China.;[Tang, Shuangyang] Univ South China, Inst Pathogen Biol, Hengyang 421001, Peoples R China.
通讯机构:
[Li, Le] U;Univ South China, Sch Publ Hlth, Hengyang 421001, Peoples R China.;Univ South China, Hunan Prov Key Lab Green Dev Technol Extremely Lo, Hengyang 421001, Peoples R China.
期刊:
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY,2018年18(12):8160-8168 ISSN:1533-4880
通讯作者:
Li, Le
作者机构:
[Lu, Wei; Liu, Ling; Chen, Tuo; Li, Le] Univ South China, Sch Publ Hlth, Hengyang 421001, Peoples R China.;[Ding, Dexin; Lu, Wei; Li, Le; Dai, Zhongran] Univ South China, Hunan Prov Key Lab Green Dev Technol Extremely Lo, Hengyang 421001, Peoples R China.;[Tang, Shuangyang] Univ South China, Inst Pathogen Biol, Hengyang 421001, Peoples R China.;[Cao, Chen] Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Peoples R China.
通讯机构:
[Li, Le] U;Univ South China, Sch Publ Hlth, Hengyang 421001, Peoples R China.;Univ South China, Hunan Prov Key Lab Green Dev Technol Extremely Lo, Hengyang 421001, Peoples R China.
关键词:
Magnetic Graphene Oxide;Calix[6]arene;U(VI);Adsorption
摘要:
Magnetic graphene oxide/calix[6] arene (MGO-C6) composites were prepared and then characterized by Fourier transform infrared spectroscopy, Scanning electron microscope, X-ray diffraction and Thermo gravimetric analyzer, the adsorption of U(VI) by MGO-C6 from aqueous solution was investigated as a function of pH, contact time, initial U(VI) concentration and adsorbent dosage. The maximum adsorption rate of MGO-C6 can reach up to 93.21%, which was highly efficient for the removal of U(VI) under the condition of 1 mg/L initial uranium concentration. In addition, the selective adsorption experiment showed that MGO-C6 had an overall preference for U(VI). Adsorption process of MGO-C6 fitted well with the pseudo-second-order kinetic kinetics and the Langmuir isotherm model. The thermodynamic parameters illustrated that the adsorption process was endothermic and spontaneous. This work demonstrated that MGO-C6 was a promising adsorbent for removal of U(VI) from low concentration uranium-containing wastewater.