Nickel carcinogenesis mechanism: cell cycle dysregulation

Environmental Science and Pollution Research - Nickel (Ni) is a widely distributed metal in the environment and an important pollutant due to its widespread industrial applications. Ni has various...     

Determination of PCBs, PCDDs and PCDFs in insulating oil samples from stored Chinese electrical capacitors by HRGC/HRMS

Homologue and congener profiles of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in commercial PCBs formulations are key information for the source identification of PCBs contamination as well as for the risk assessment caused by potential exposure. The isotope dilution technology in combination with high resolution gas chromatography-high resolution mass spectrometry (HRGC/HRMS) has made the accurate determination of such profiles possible. So far, various commercial PCB formulations except Chinese products have been successfully determined. Two PCBs containing insulating oil samples from stored Chinese electrical capacitors have been determined with the same methodology for comparability. The total concentration PCBs in two oil samples were 790 000 μg g⁻¹ and 720 000 μg g⁻¹, respectively. TriCBs, TetraCBs, and DiCBs were found to be most abundant. Concentration of dioxins contamination in two samples is 650-670 ngTEQ g⁻¹, of which 69-71 ngTEQ g⁻¹ from PCDD/Fs with the predominant congeners of 1,2,7,8-TeCDF; 2,3,7,8-TeCDF; 2,3,4,7,8-PeCDF and 1,2,3,7,8-PeCDF. The contributions of DL-PCBs in total TEQ in both samples were more than 85%. The dioxin-like toxicity in insulating oils contained in electrical capacitors could be considered receive attention as an important dioxins source if such wastes are not managed in an environmentally sound manner.     

标准化测试种子发芽和根伸长毒性试验的基质应用研究

种子发芽和根伸长毒性试验是研究和评价新化学物质对陆生生物危害性的重要手段之一。为探究在标准化测试中能否使用非推荐基质,以及使用推荐基质时能否用灭菌法替代酸洗法处理石英砂,选取8种植物种子在5种基质中进行试验。结果表明,不同基质对种子发芽率的影响较小,但基质较低的养分含量和特殊的物理结构易对部分种子根长形成胁迫,甚至直接制约根系发育。生菜、水稻在5种基质中的发芽率和根长无显著性差异;绿豆、甘蓝、西瓜在酸洗石英砂中的根长分别为25.1、24.5、29.0 mm,在其余4种基质中根长显著缩短;青瓜在吸水纸和发芽纸中发芽率偏低,仅为83.3%;玉米在酸洗石英砂和灭菌石英砂中的发芽率和根长无明显差异,为100%/45.7 mm和93.3%/44.8 mm,其他基质中显著偏低。标准化测试条件下,以推荐的酸洗石英砂上各种子的发芽率和根长为评判依据,生菜和水稻试验可使用本研究中任意基质,绿豆、甘蓝和西瓜试验仅可使用酸洗石英砂作为基质,青瓜和玉米试验可使用干热灭菌法替代酸洗法处理石英砂,并且青瓜试验还可使用滤纸基质。以上结果为测试机构在工作实践中优化试验条件提供理论依据。     

铁(Ⅲ)-羧酸配合物对水溶性染料的光化学脱色动力学的比较研究

铁-柠檬酸，铁-酒石酸，铁-丁二酸，铁-草酸配合物在高压汞灯（λmax＝313nm，250W）的照射下，能使活性艳红X－3B染料水溶液脱色。染料初始浓度在10mg／L～50mg／L时，染料脱色为动力学一级反应，脱色速率随初始浓度增大而降低。在pH2．0～3．0时铁-柠檬酸，铁-滴石酸，铁-丁二酸的染料溶液脱色效果较佳，在pH4．0时铁-草酸的染料溶液脱色效果最好。铁／羧酸盐配比对染料脱色速率也有影响。     

某冶炼厂拆迁场地土壤重金属污染健康风险评价

按照环保部最新颁布实施的污染场地风险评估技术导则(HJ 25.3—2014),选取Cu、Pb、Zn、Cd、Cr、As 6种重金属元素为主要污染物,结合Pearson相关分析及克里金差值法,对某冶炼厂拆迁场地土壤进行健康风险评价。结果表明:拆迁场地土壤中重金属污染集中于生产区及堆放场,污染程度为生产区≈堆放场生活区,6种重金属平均值低于《展览会用地土壤环境质量评价标准》B级(HJ 350—2007),Pb、Zn、Cd平均值高于广西省和中国土壤元素背景值;相关分析表明Cu分别与Pb、Zn、Cr、As,Pb-Cr、Pb-As及Zn-Cd存在极显著正相关关系;健康风险评价结果表明生活区土壤中6种重金属对人体健康不会产生不良或危害效应;生产区和堆放场土壤中Cr存在致癌风险,As存在致癌风险和非致癌危害。成人血铅模型(ALM)计算得出生活区、生产区及堆放场中成人血铅浓度值分别为4.98μg·d L-1、5.04μg·d L-1、5.03μg·d L-1,低于成人血铅浓度风险评价的基准值5.8μg·d L-1,且Pb的平均值低于国内外居住用地土壤铅环境基准值。     

关于黄土高原陇东地区环境变化的回顾与思考

在近七八十年里,生态环境脆弱的陇东地区由于人口增加引起乱砍滥伐、过度放牧、陡坡开垦造成的水土流失和引起大量开垦坡地,广种薄收,形成“越穷越垦、越垦越穷”的恶性循环等等,出现了一系列人地矛盾.随着植树造林,退耕还林,禁止放牧等一系列政策措施的实施和社会经济的快速发展,使得这一矛盾得到了一定程度的缓解,可今后怎样保持和继续深化以及怎样在环境可承载下发展经济和提高人民的生活水平是我们要思考的问题.从环境变化的几个方面进行讨论并得出一些存在的问题及建议.     

Organohalogenated compounds in pine needles from Beijing city, China

Pine needles collected from 22 sites of six areas in Beijing city, China, were analyzed by instrumental neutron activation analysis (INAA) combined with organic extraction for extractable organohalogens (EOX) and extractable persistent organohalogens (EPOX). The concentrations of EOX (EOX = ECl + EOBr + EOI) were in the order of EOCl > EOBr > EOI. About 1.6-34% of EOCl remained as extractable persistent organochlorine (EPOCl) after treatment with concentrated sulfuric acid, which suggested that major fractions of EOCl in pine needles were an acid-liable or acid-soluble fraction. The fact that pine needle contained higher EOCl contents in chemical industrial and traffic hub areas indicated that chemical industries and exhaust emission from vehicle were the main sources of organochlorines in the Beijing's air. The relative proportions of the known organochlorines (such as HCHs, DDTs, chlordanes, HCB and PCBs) to total EOCl and EPOCl were 0.32-0.76% and 2.5-11.4%, respectively, which implied that a major portion of the EOCl and EPOCl measured in pine needles was unknown. The organochlorinated pesticides (OCPs) and PCBs concentrations in six areas were as follows: sigma HCH (sigma HCH = alpha- + beta- + gamma- + delta-HCH), 11.7-20.8 ng/g; sigma DDT (p,p'-DDT + p,p'-DDE + p,p'-DDD), 12.5-113.3 ng/g; hexachlorobenzene (HCB), 1.1-5.3 ng/g; sigma chlordane (cis-chlordane + trans-chlordane + heptachlor), 1.7-9.5 ng/g, sigma PCB, 41.8-270.5 ng/g, on dry weight basis. The samples from chemical industrial area and residential area nearby chemical industries contained the highest concentrations of sigma DDT, HCB, sigma chlordane and sigma PCB, while the contamination levels of most OCPs and PCBs in iron-steel industrial area were the lowest. The ratios of alpha/gamma-HCH (ranged from 0.9-1.5) and p,p'-DDT/DDTs (ranged from 72.1% to 91.0%) revealed the presence of the recent use of lindane and DDTs or impure dicofol in Beijing.     

Water pollution and degradation in Pearl River Delta,South China

The Pearl River Delta Economic Zone is the most dynamic economic area in South China. One of the major problems in the region is the sustainable utilization of the water resources. On the basis of analysis of the water environment status and pollution sources, it is suggested that domestic sewage is the primary cause of pollution. Two new concepts "degradation coefficient" and "degradation volume" of water resources, due to pollution, which may be used to assess macroscopically the carrying capacity of the water resources and sustainability of the water environment, are proposed by the authors. The results calculated indicate that the volumes of degraded water resources will be up to 204, 352, and 537 million m3 in 2002, 2010, and 2020. It is suggested that water for daily consumption and domestic sewage must be controlled more effectively and there should be cross-regional coordination in tackling problems of water environment.     

垃圾焚烧炉燃烧过程的优化控制策略

焚烧炉控制旨在使城市垃圾经处理后达到无害化、减量化和资源化的目标,既有利于环境保护,也有良好的社会经济效益。针对垃圾焚烧过程中由于燃烧对象复杂性导致的控制难题,提出了一种对垃圾焚烧系统实施优化控制的仿人智能控制策略。研究出稳定燃烧评判指标、控制模型、工程控制算法,并进行仿真试验。系统仿真试验结果表明:仿人智能控制策略鲁棒性强、控制品种好,是一种有效的控制策略。     

Is there a silver lining? Aggregation and photo-transformation of silver nanoparticles in environmental waters

Is the aggregation of silver nanoparticles in environmental waters a silver lining? The answer is not simple. Clearly, however, the aggregation and photo-transformation of AgNPs are complicated and could be more significant than previously thought. The difference in the water chemistry that controls the aggregation and photo-transformation of AgNPs results in the varying behavior and fate of AgNPs among different water bodies.