Bioaccumulation and changes of trace metals over the last two decades in marine organisms from Guangdong coastal regions, South China

Trace metal(Cr, Ni, Cu, Zn, Cd and Pb) exposures, distribution and bioaccumulation were investigated in marine organisms from Guangdong coastal regions, South China. The results showed that all of the selected metals were observed in marine organisms with a predomination of Cu and Zn. The metal exposure levels exhibited obvious variations between species with the decreasing order of crab > shellfish > shrimp > fish. The higher metals enrichment seen in shellfish and crab species primari...     

2018年春节期间京津冀及周边地区烟花禁放效果评估

为了评估2018年春节期间（2月15—16日）京津冀及周边地区“2+26”城市烟花禁限放措施的效果,采用浓度特征对比、ρ（PM_2.5）/ρ（CO）等方法,对“2+26”城市的ρ（PM_2.5）、ρ（PM₁₀）、ρ（SO₂）、ρ（NO₂）进行分析,并定量估算了除夕夜烟花燃放对ρ（PM_2.5）和ρ（SO₂）的贡献率.结果表明:“2+26”城市烟花的集中燃放会导致ρ（PM_2.5）、ρ（SO₂）显著增长,出现以PM_2.5为首要污染物的重污染时段,2018年12月16日03:00区域内14个城市ρ（PM_2.5）达到重度及以上污染水平,呈区域性污染特征;与2017年同期（1月27—28日）相比,2018年春节期间（2月15—16日）14个城市烟花燃放对ρ（PM_2.5）平均贡献量呈下降趋势,其中,淄博市、济南市、北京市降幅最大,分别下降了85.2%、74.6%和65.2%,表明烟花禁限放措施起到了显著的污染削峰作用;与城区相比,周边郊县ρ（PM_2.5）显著高于城区,呈“农村包围城市”的现象,说明城区监测点位受到郊县等周边地区烟花燃放的传输影响.研究显示,虽然城区烟花禁限放措施起到了显著的削峰作用,但城区监测点位空气质量仍受到郊县等周边地区烟花燃放的传输影响,导致大气重污染的发生.      

万州城区夏季、冬季PM_(2.5)中有机碳和元素碳的浓度特征

在位于三峡库区腹心的山地城市万州城区采集夏季和冬季PM2.5样品,采用热光反射法(Thermal Optical Reflection,TOR)测定了PM2.5中有机碳(OC)和元素碳(EC)的浓度,探讨了其污染特征及来源.结果发现,OC和EC在夏季的平均浓度分别为(7.09±1.86)μg·m-3和(3.49±0.64)μg·m-3;冬季分别为(16.82±6.87)μg·m-3和(6.21±2.06)μg·m-3,高于夏季,这可能与冬季当地居民生物质燃烧的贡献显著增加有关.冬季OC和EC显著线性相关(r=0.89),表明冬季两者的一次污染来源相近.冬季PM2.5中总碳(TC)和水溶性K+含量的相关性(r=0.88)高于夏季(r=0.69),表明冬季生物质燃烧对碳污染贡献显著.利用OC/EC比值法对二次有机碳(SOC)进行估算,SOC的浓度均值在夏季为(2.17±1.46)μg·m-3,占OC比例为28.18%±13.85%;冬季为(4.46±3.69)μg·m-3,占OC的23.13%±12.30%.通过计算PM2.5中8个碳组分丰度,初步判断机动车尾气排放和生物质燃烧是万州城区碳组分的主要来源.     

Reed-wetland beds for municipal wastewater treatment

The performance of 11 reed-wetland beds for municipal wastewater treatment is described in this paper. The interrelation between pollutants removal (BOD5, SS, N and P) and hydraulic loading rate, organic loading rate, hydraulic retention time as well as the seasonal variation could be found in this study. The treatment efficiencies of reed beds are better than the secondary treatment standards with high and steady nitrogen and phosphorus removal. The total nitrogen and phosphorus of the final effluent are less than 10 mg/L and 0.5 mg/L, respectively.     

处理重金属废水技术的研究进展

如何消除工业废水中重金属对环境和人类健康的危害，并且能够有效地回收废水中的贵重金属离子是环境保护工作者需解决的热点问题之一。详细她介绍了近十几年来国内外，处理重金属废水的技术方法，包括传统方法中的化学沉淀法、电化学法、吸附法和膜分离法，新出现的技术方法如分子印迹法和光催化法，并对以上各种技术方法的机理、研究进展、优点和所面临的主要问题进行了综合评述，同时阐述了处理重金属废水的技术和方法的发展趋势和应用前景。     

自制固相微萃取装置-气相色谱法测定空气中痕量苯

采用自制的固相微萃取(SPME)装置结合气相色谱仪(GC)对室内空气中痕量苯进行定性和定量的分析。阐述了固相微萃取法的原理和定量的机理;对影响SPME的因素(空气柱、萃取时间、解吸时间和温度)进行了讨论;对所建立的方法进行了系统评价,结果表明:建立的方法具有良好的线性关系(相关系数R=0.9998),检出限为0.01mg/L,3个含量点的相对标准偏差在允许的范围7%以内,回收率为98.18%。     

Diffusion of polybrominated diphenyl ether (PBDE) from an e-waste recycling area to the surrounding regions in Southeast China

Using Cinnamomum camphora (C. camphora) leaves as biomonitors, we investigated that the diffusion of polybrominated diphenyl ethers (PBDEs) from an e-waste recycling area to the surrounding regions. Variance in ∑₃₂PBDEs concentrations (0.46–399.93 ng g⁻¹ dry weight) in the leaves showed that PBDEs from the e-waste recycling area diffused into the surrounding regions, and resulted in a halo of PBDEs contamination, at least 74 km in radius. The attenuation of ∑₃₂PBDEs in the diffusing process fitted in log-linear regression. The difference in the attenuating slopes of linear equations among different directions can be explained by terrain and wind direction. The attenuation of PBDE congeners also fitted well in log-linear regression. The findings that similar attenuating slopes and characteristic travel distance among congeners suggest that the transport behavior of lower brominated congeners might not differ from that of higher brominated congeners in short-range scale.     

The use of experimental data and their uncertainty for assessing ozone photochemistry in the Eastern Iberian Peninsula

Observation-based methods are useful tools to explore the sensitivity of ozone concentrations to precursor controls. With the aim of assessing the ozone precursor sensitivity in two locations: Paterna (suburban) and Villar del Arzobispo (rural) of the Turia river basin in the east of Spain, the photochemical indicator O₃/NO_y and the Extent-of-Reaction (EOR) parameter have been calculated from field measurements. In Paterna, the O₃/NO_y ratio varied from 0 to 13 with an average value of 5.1 (SD 3.2), whereas the averaged value for the EOR was 0.43 (SD 0.14). In Villar del Arzobispo, the O₃/NO_y ratio changed from 5 to 30 with a mean value of 13.6 (SD 4.7) and the EOR gave an averaged value of 0.72 (SD 0.11). The results show two different patterns of ozone production as a function of the location. The suburban area shows a VOC-sensitive regime whereas the rural one shows a transition regime close to NO_x-sensitive conditions. No seasonal differences in these regimes are observed along the monitoring campaigns. Finally, an analysis of the influence of the measurement quality of NO_y, NO_x and O₃ on the uncertainty of the O₃/NO_y ratio and the EOR was performed showing that the uncertainty of O₃/NO_y is not dependent on either its value or the individual values of O₃ and NO_y but just on the quality of O₃ and NO_y measurements. The maximum uncertainty is 26% as long as the combined uncertainties of O₃ and NO_y remain below the 7.5%. The case of the EOR is different and its uncertainty depends on both the value of the EOR parameter and the individual concentration values of NO_y and NO_x. The uncertainty of the EOR estimation can be very high (>200%) if the combined uncertainties of both NO_y and NO_x are high (>7.5%), or especially, if u(NO_y) and u(NO_x) differ considerably from each other (>3.5%).     

Photolytic degradation of decabromodiphenyl ethane (DBDPE)

The photolytic degradation of decabromodiphenyl ethane (DBDPE), an alternative flame retardant to decabromodiphenyl ether, was investigated in a variety of matrixes (n-hexane, tetrahydrofuran, methanol/water, humic acid/water, and silica gel) by irradiation under ultraviolet light and in n-hexane under natural light. Photolytic degradation of DBDPE occurs in all the matrixes investigated within the irradiation period (<320 min). The degradation experiments showed varied reaction rates, dependent on the matrixes, with increasing half-lives (t_1/2) in the order of tetrahydrofuran (t_1/2 = 6.0 min) > n-hexane (t_1/2 = 16.6 min) > humic acid/water (30 < t_1/2 < 60) > silica gel (t_1/2 = 75.9 min) > methanol/water (t_1/2 > 240 min). The reaction in tetrahydrofuran, n-hexane, and silica gel matrixes can be described by the pseudo first order kinetics. Nevertheless, the matrixes have little effect on the degradation product distributions of DBDPE. A numbers of debrominated intermediates were identified. The degradation involves the initial formation of nona-BDPEs and the subsequent decomposition of these congeners to lower brominated congeners (octa- and hepta-BDPEs) within the irradiation time. To our knowledge, the present work is the first attempt to investigate the photolytic degradation kinetics and the identification of intermediates, as well as the degradation mechanism, during the degradation of DBDPE. Further research is needed to understand the photolytic degradation pattern of DBDPE in the natural environment.     

集中式饮用水水源地水质预警指标体系构建

饮用水水源地水质预警是建立健全饮用水安全保障体系的关键环节,构建水源地水质预警指标体系是水源地监控预警工作的重要基础。系统分析了常规水质在线、生物毒性在线、卫星遥感、人工巡视等水质预警监测技术手段,并分析比较了各方法的优缺点。以此为基础,遵循水源地预警指标体系构建原则与实际需求,统筹兼顾,提出了建立以常规理化-生物毒性在线监测相结合,遥感监测与人工巡查相统筹的一体化水源地水质预警指标体系,为水源地水质预警监控工作提供合理的、科学的技术支撑。