Trace Metals in Upland Headwater Lakes in Ireland

Trace elements (n = 23) in Irish headwater lakes (n = 126) were investigated to determine their ambient concentrations, fractionation (total, dissolved, and non-labile), and geochemical controls. Lakes were generally located in remote upland, acid-sensitive regions along the coastal margins of the country. Total trace metal concentrations were low, within the range of natural pristine surface waters; however, some lakes (~20 %) had inorganic labile aluminum and manganese at levels potentially harmful to aquatic organisms. Redundancy analysis indicated that geochemical weathering was the dominant controlling factor for total metals, compared with acidity for dissolved metals. In addition, many metals were positively correlated with dissolved organic carbon indicating their affinity (or complexation) with humic substances (e.g., aluminum, iron, mercury, lead). However, a number of trace metals (e.g., aluminum, mercury, zinc) were correlated with anthropogenic acidic deposition (i.e., non-marine sulfate), suggesting atmospheric sources or elevated leaching owing to acidic deposition. As transboundary air pollution continues to decline, significant changes in the cycling of trace metals is anticipated.     

Mobility of radionuclides in soil/groundwater system: Comparing the influence of EDTA and four of its degradation products

The adsorption behavior of ²⁴¹Am, ⁶⁰Co, ¹³⁷Cs and ⁸⁵Sr in the presence and absence of chelating ligands (ethylenediaminetetraacetic acid, ethylenediaminediacetic acid, hydroxyethyliminodiacetic acid, iminodiaceiticacid and methyliminodiacetic acid) was investigated. Sorption affinity in the absence of chelating ligands followed: Am(III) > Co(II) > Cs(I) > Sr(II). The presence of chelating ligands generally had little effect on sorption of ⁸⁵Sr and ¹³⁷Cs with K_d values 110 and 690 mL g⁻¹, respectively. But at 0.02 M of ethylenediaminetetraacetic or hydroxyethyliminodiacetic, the K_d decreased to 5 or 63 mL g⁻¹, respectively, where thermochemical modeling indicated almost all ⁸⁵Sr is complexed with these ligands. The K_d values for ²⁴¹Am and ⁶⁰Co generally decreased with increasing chelating agent concentrations. In notable cases, the K_d values for Am increased at specific concentrations of 10⁻³ M for IDA, MIDA and 10⁻⁴ M for EDDA. This is proposed to be due to formation of a ternary surface complex.     

荧光分光光度法测定海洋生物体中石油烃前处理方法优化

海洋生物体中的石油烃质量分数是海洋环境监测评价体系的重要指标,现行分析方法标准为《海洋监测规范第6部分:生物体分析》(GB 17378.6—2007)荧光分光光度法,该标准方法中前处理操作较为复杂,实际样品分析中存在样品平行性差、加标回收率范围宽等问题。由于样品均匀性、皂化进程、萃取分离操作手法等因素均会影响样品测定结果的平行性和精密度水平。因此,对比了不同制备方式的样品(干样和匀浆样),通过过滤或离心的方式去除了皂化液中的非石油烃大分子干扰;并对比了不同皂化温度和时间,获得了最优的前处理方法,提升了方法的准确度和精密度。对实际海洋生物体样品的分析表明,优化后的方法检出限为0.9 mg/kg,变异系数为7.02%~14.4%,加标回收率为67.4%~138%,精密度和准确度良好,基本满足海洋生物体中石油烃测定的要求。     

超临界流体技术在化工污染治理中的应用

对于许多化工产品废物,如塑料、有毒物质、生物污泥和有机废水等,利用传统技术进行处理的效果较差。超临界流体(SCF)技术作为一种清洁环境的新技术,可用于治理化工污染物。SCF作为反应介质或反应物可替代有毒、有害有机溶剂;用作萃取剂,它是一种新型的分离技术;以SCF作移动相的色谱,可提高检测灵敏度和分辨率;将超临界水作为氧化剂,可破坏有机污染物的结构。SCF技术的应用可以大大减少环境污染。     

Changes in the chemical composition of water-extractable organic matter during composting: distribution between stable and labile organic matter pools

Aerobic decomposition and stabilization of organic matter during the composting of waste materials is primarily due to the biochemical transformation of water-soluble compounds in the liquid phase by the microbial biomass. For this reason water-soluble organic matter represents the most active fraction of compost, both biologically and chemically, and thus should directly reflect the biochemical alteration of organic matter. This work aims to elucidate the microbial-mediated processes responsible for the distribution of soluble organic matter between stable and labile pools with composting time. Accordingly, chemical analysis as well as UV absorption, and ¹H and ¹³C-NMR spectroscopy of samples collected during the industrial composting of urban waste revealed microbial induced transformation of water-extractable organic matter over time. The chemical composition changed from labile, hydrophilic, plant-derived organic compounds in the beginning to predominately stable, hydrophobic moieties comprising lignin-derived phenols and microbially-derived carbohydrates at later stages of composting.     

微囊藻毒素-RR的提取和臭氧氧化降解

在对采自云南滇池水华蓝藻细胞中的微囊藻毒素-RR(microcystin-RR,MC-RR)提取并发现其含量达到0.19mg/g(干重)的基础上,重点研究了臭氧氧化降解所提取的MC-RR。结果表明,当反应体系中臭氧浓度为5.7 mg/L时,初始浓度1.9 mg/L的MC-RR在15 min内被完全降解。利用HPLC/ESI/MS对提取的MC-RR及其氧化降解产物质荷比测定发现,降解前MC-RR的质谱图中出现特征离子m/z=1 038.7、m/z=519.8以及m/z=135.0。而降解后的产物质谱图中只有Adda基团中带苯环结构化合物(C9H10O)的特征离子峰m/z=135.0存在,其他2个离子峰完全消失。由此推断反应体系中MC-RR(m/z=1 038.2)在大量臭氧及其.OH自由基全面攻击下,分子结构中Adda基团以及单环结构中的不饱和双键直接被氧化而发生断链,最终形成小分子的有机物。     

太湖以西常州区域水体中典型PPCPs污染特征

为进一步了解环太湖区域药品及个人护理用品（PPCPs）环境污染现状,于2016年9月对太湖以西常州区域水体中典型PPCPs污染水平进行了调查。利用高效液相色谱-串联质谱（HPLC MS/MS）检测分析了24种PPCPs在常州区域水体中的赋存和空间分布特征。结果表明,常州区域水体中24种目标PPCPs均被检出,PPCPs质量浓度总量范围为51.08～325.79 ng/L,20个监测点位中,红凌桥检出PPCPs总量最高,达325.79 ng/L;水体中优势污染物为双酚A和诺氟沙星,双酚A在黄埝桥检出的质量浓度最高,达158.53 ng/L,其次是新河口和红凌桥,质量浓度分别为65.57和57.86 ng/L;诺氟沙星在红凌桥检出的质量浓度最高,达75.12 ng/L。喹诺酮类抗生素、磺胺类抗生素在常州流域内基本呈均匀分布;激素类、大环内酯抗生素、神经镇痛类和心脏病类药物质量浓度与人口密度大致呈正相关。     

新时期生态环境监测数据产品内涵和发展建议

简述了新时期环境监测数据产品内涵,分析了当前数据产品在信息化程度、深度开发、数据质量和信息公开等方面存在的问题;提出,要不断提高数据产品的信息化水平,推进其深度开发,要立足于服务社会和管控需求,加强数据产品可追溯能力建设,针对现各部门存在的\"数据孤岛\"问题,增强各部门间监测数据的可比性,推进区域污染物排放、空气环境质量、水环境质量等信息公开,为政府决策提供准确的技术支持,为公众、企业提供优质服务。