Chlorinated and polycyclic aromatic hydrocarbons in riverine and estuarine sediments from Pearl River Delta, China

Spatial distribution of chlorinated hydrocarbons [chlorinated pesticides (CPs) and polychlorinated biphenyls (PCBs)] and polycyclic aromatic hydrocarbons (PAHs) was measured in riverine and estuarine sediment samples from Pearl River Delta, China, collected in 1997. Concentrations of CPs of the riverine sediment samples range from 12 to 158 ng/g, dry weight, while those of PCBs range from 11 to 486 ng/g. The CPs concentrations of the estuarine sediment samples are in the range 6-1658 ng/g, while concentrations of PCBs are in the range 10-339 ng/g. Total PAH concentration ranges from 1168 to 21,329 ng/g in the riverine sediment samples, whereas the PAH concentration ranges from 323 to 14,812 ng/g in the sediment samples of the Estuary. Sediment samples of the Zhujiang River and Macao harbor around the Estuary show the highest concentrations of CPs, PCBs, and PAHs. Possible factors affecting the distribution patterns are also discussed based on the usage history of the chemicals, hydrologic condition, and land erosion due to urbanization processes. The composition of PAHs is investigated and used to assess petrogenic, combustion and naturally derived PAHs of the sediment samples of the Pearl River Delta. In addition, the concentrations of a number of organic compounds of the Pearl River Delta samples indicate that sediments of the Zhujiang river and Macao harbor are most likely to pose biological impairment.     

Organochlorine compounds and polycyclic aromatic hydrocarbons in surface sediment from Baiyangdian Lake, North China： Concentrations, sources profiles and potential risk

Organochlorine pesticides(OCPs),polychlorinated biphenyls(PCBs),and polycyclic aromatic hydrocarbons(PAHs) were determined in nineteen surface sediment samples collected from Baiyangdian Lake and its inflowing river(Fuhe River) in North China.Total concentrations of OCPs,PCBs and PAHs in sediments ranged from 5.4 to 707.6 ng/g,2.3 to 197.8 ng/g,and 101.3 to 6360.5 ng/g,respectively.The levels of contaminants in Fuhe River were significantly higher than those in Baiyandian Lake.For hexachlorocyclohexane(HCHs) and dichlorodiphenytrichloroethanes(DDTs),α-HCH and p,p-DDT were predominant isomers;while for PCBs,PCB 28/31,PCB 40/103,PCB 60,PCB 101,and PCB 118 were predominant congeners.Possible sources derived from historical usage for OCPs and incomplete combustion fuel,wood,and coal and exhaustion of boats or cars for PAHs.Risk assessment of sediment indicated that sediments in Fuhe River were likely to pose potential biological adverse impact.     

沉积物中多环芳烃和有机氯农药定量分析的质量保证和质量控制

以美国ＥＰＡ为方法为基础,进行了沉积物中多环芳烃和有机氯农药分析的质量保证和质量控制实验,采用回收率指示物控制回收率,用内标法定量。结果表明多环芳烃的指示物回收率为５０．６７－９７．３３％,目标化合物的回收率为５８．６７－９６．３３％,方法检测限为３．３０－９．２６μｇ．ｋｇ＾－１。     

铁屑对低浓度含铬地下水的处理研究

以某铬渣污染场地上抽提上来的低浓度含铬地下水作为实验研究对象。选用铁屑对含铬废水进行处理。通过静态试验考察了影响六价铬去除率的因素:pH、铁屑用量、反应时间,得到了较好的反应工艺参数。并在静态试验的基础上,用铁屑填充自制的反应柱研究了动态试验的效果。结果表明:六价铬的出水浓度低于0.05 mg/L,达到GB/T 14848-93《地下水质量标准》Ⅲ类排放标准。     

Potential energy production from organic waste and its environmental and economic impacts at a tertiary institution in Palestine

Municipal solid waste (MSW) is one of the most well-known biomass resources that can be utilized to produce renewable energy. Numerous countries are plagued by the proliferation of waste, particularly organic waste that can be utilized for energy recovery. Palestine suffers from inefficient solid waste management, and only recently have a few projects focused on bioenergy production been implemented. Throughout the years, the city of Tulkarm experiences power outages which cause a challenge to the Palestine Technical University-Kadoorie campus in Tulkarm. Thus, the possibility of energy recovery from the organic portion in Palestine Technical University-Kadoorie was evaluated. The analysis of an economic impact included discussions of a number of economic aspects, including Levelized cost of energy, internal rate of return, present worth, annual worth, and payback period. On the other hand, a carbon dioxide savings analysis and gas emission were evaluated. The outcomes of the energy optimization demonstrated that the suggested system could supply the institution with an average of roughly 7 MWh of electrical energy. According to the economic study, this project offers 0.25 million dollars in present value, 0.144 million dollars in annual value, a 13 percent internal rate of return, a payback period of 6 years, and a levelized cost of energy of 0.11 dollars for each kWh generated. Additionally, the environmental assessment revealed that this system might reduce CO₂ emissions by around 8,343,778 tons. For effective waste management, energy recovery, and emission reduction, it is advised to implement anaerobic digestion technology.     

磷酸三(1,3-二氯-2-丙基)酯导致小鼠神经毒性结局的潜在靶点研究

磷酸三(1,3-二氯-2-丙基)酯(TDCPP)在环境介质及生物样本中被广泛检出,为探究TDCPP的潜在神经毒性以及作用机制,以C57BL/6小鼠为动物模型,考察经300 mg·kg-1·d-1的TDCPP持续染毒35 d后,小鼠大脑皮层神经功能相关因子及血清代谢组学的变化.结果显示,小鼠在TDCPP染毒35 d后,大脑皮层中5-羟色胺(5-HT)含量和乙酰胆碱酯酶(AChE)活性无显著变化(P＞0.05),而促炎性细胞因子白细胞介素-6(IL-6)、白细胞介素-1β(IL-1β)、肿瘤坏死因子-α(TNF-α)、诱导型一氧化氮合酶(iNOS)及胶质细胞源性神经营养因子(GDNF)基因表达水平显著上调(P＜0.05),神经营养因子-3(Ntf3)基因表达水平显著下调(P＜0.05);同时,TDCPP染毒显著干扰了小鼠的代谢过程,引起异亮氨酸、谷氨酸、甘氨酸和β-葡萄糖等多种神经性疾病相关生物标志物的改变,以及氨基酸代谢、糖类代谢和脂质代谢紊乱.研究结果表明,TDCPP的神经毒性效应与神经炎症和神经元损伤相关因子转录水平改变,以及代谢失衡引起的信号紊乱有关.     

合流制雨水泵站溢流污水消毒试验研究

论述了合流制排水系统污水溢流消毒处理的必要性。提出采用粪大肠杆菌群数≤104个/L作为污水消毒的卫生学指标。试验结果表明,达到CSO紧急消毒要求的几种氧化性消毒剂最佳投加量为次氯酸钠30mg/L,次氯酸钙25mg/L,二氧化氯20mg/L(均以有效氯计);二氧化氯>次氯酸钙>次氯酸钠>双氧水。     

Increasing polybrominated diphenyl ether (PBDE) contamination in sediment cores from the inner Clyde Estuary,UK

The concentrations of 16 polybrominated diphenyl ether (PBDE) congeners in six short sediment cores from the Clyde Estuary were determined by gas-chromatography mass-spectrometry. Total PBDE concentrations ranged from 1 to 2,645 μg/kg and the average concentration was 287 μg/kg. BDE-209 was the main congener and varied from 1 to 2,337 μg/kg. Elevated total PBDE concentrations were observed close to the sediment surface in the uppermost 10 cm of four of the six sediment cores. Comparison of the down core PBDE profiles revealed that the increase was driven by the accumulation of deca-BDE. Although the deca-BDE mix was dominant, the presence of lower molecular weight congeners BDE-47, BDE-99, BDE-183 and BDE-153 at most sediment intervals suggested additional sources of penta-BDE and octa-BDE pollution. Changing PBDE source input was the major factor in influencing the proportion of nona-brominated congeners, although other explanations such as post burial photo-debromination of BDE-209 cannot be entirely discounted. A clear cascading to lower hepta-, hexa-, and penta-homologues was not found. The increase in total PBDE concentrations and particularly the deca-BDE may possibly be ascribed to the use and subsequent disposal of electrical appliances such as televisions and computers. In the Clyde sediments, the proportion of nona-brominated congeners was higher than that reported for commercial mixtures. This might be due to changing sources of PBDEs or post burial photo-debromination of BDE-209.     

Contents and sources of polycyclic aromatic hydrocarbons and organochlorine pesticides in vegetable soils of Guangzhou, China

We investigated contents, distribution and possible sources of PAHs and organochlorine pesticides (Ops) in 43 surface and subsurface soils around the urban Guangzhou where variable kinds of vegetables are grown. The results indicate that the contents of PAHs (16 US EPA priority PAHs) range from 42 to 3077 microg/kg and the pollution extent is classified as a moderate level in comparison with other investigations and soil quality standards. The ratios of methylphenanthrenes to phenanthrene(MP/P), anthracene to anthracene plus phenanthrene (An/178), benz[a]anthracene to benz[a]anthracene plus chrysene (BaA/228), indeno[1,2,3-cd]pyrene to indeno[1,2,3-cd]pyrene plus benzo[ghi]perylene (In/In+BP) suggest that the sources of PAHs in the soil samples are mixed with a dominant contribution from petroleum and combustion of fossil fuel. The correlation analysis shows that the PAHs contents are significantly related to total organic carbon contents (TOC) (R2=0.75) and black carbon contents (BC) (R2=0.62) in the soil samples. Dichlorodiphenyltrichloroethane and metabolites (DDTs) and hexachlorocyclohexanes and metabolites (HCHs) account largely for the contaminants of OPs. The concentrations of DDTs range from 3.58 to 831 microg/kg and the ratios for DDT/(DDD+DDE) are higher than 2 in some soil samples, suggesting that DDT contamination still exists and may be caused by its persistence in soils and/or impurity in the pesticide dicofol. The concentrations of HCHs are 0.19-42.3 microg/kg.