“引江济太”过程中塑化剂类污染物的输入特征和环境健康风险评价

为了解"引江济太"过程中塑化剂类污染物对贡湖的输入特征,于2013年8月对14个采样点的7种邻苯二甲酸酯类化合物(PAEs)的浓度进行采样分析,并通过美国环保署(USEPA)推荐的方法,对其环境风险进行评价.结果表明:各采样点邻苯二甲酸二丁酯(DBP)和邻苯二甲酸二环己酯(DCHP)均有检出,除采样点10、11和12外,邻苯二甲酸二乙酯(DEP)也有检出,其余4种均未检出,长江引水经望虞河进入贡湖后,DEP、DBP和DCHP浓度均有不同程度的降低,且其最高浓度均出现在望虞河长江引水处(采样点1),说明在引水过程中长江水对望虞河有明显的PAEs输入,而贡湖锡东水厂DEP浓度高于贡湖其他采样点,南泉水厂DBP和DCHP浓度高于贡湖其他采样点,金墅湾水厂PAEs浓度总体处于较低水平.环境健康风险评价结果显示:DEP的最大非致癌风险值为3.91×10-8a~(-1),未超过国际组织规定范围,而DBP的最大非致癌风险值为1.17×10-5a~(-1),超过英国皇家协会RS规定的1×10-6a~(-1),但均对人体无明显非致癌危害.     

绿洲边缘新月形沙丘表层沉积物粒度与重金属分布特征

本文以乌兰布和沙漠绿洲边缘工业化城市乌海市下风向典型新月形沙丘为研究对象,分析了新月形沙丘各部位0~10 cm沙物质、沙丘前50 m处大气降尘的粒度及重金属元素变化特征,探讨了重金属物质的来源及其与粒径的相关性,评价了重金属的潜在生态风险.结果表明:沙丘各部位沉积物粒度均以细砂为主,较对照沙丘极细砂含量增高而中砂含量减少.而降尘主要以极细砂、粉粒为主,降尘在沙丘表面的沉降堆积使沙丘表层沙物质细化.沙丘与降尘的重金属含量均为FeMnCrZnCu;Mn、Cu、Zn、Cr含量均高于背景值且发生富集.Mn、Zn含量在空间分布上呈中等变异;Fe、Cu含量在空间分布上为高度变异.Mn、Zn、Cu含量与细颗粒含量呈显著正相关,Zn、Cu含量与中砂含量呈负相关,Fe含量与细砂和中砂含量均呈负相关.Cu、Zn、Cr为人为污染因子,Mn、Fe为自然源因子,但Cr、Mn、Fe又受到自然地质背景和人类活动的共同控制.乌海市下风向新月形沙丘属于低生态风险状态,为轻度污染,需加强废气的治理控制以防重金属污染的进一步加深.     

我国生物质气化发电行业综合风险评价

针对我国生物质气化发电行业的现状,总结诸多风险的影响因素,建立了我国生物质气化发电行业综合风险评价体系。该评价体系主要包括5个一级风险影响因素:市场风险、技术风险、安全风险、管理风险、环境风险,每个一级影响因素包括4个二级风险影响因素。由层次分析法获得各个一级影响因素和二级影响因素的权重值,根据所构建的评价集和评分标准,结合模糊综合评价法对我国生物质气化发电行业现状的综合风险等级做定量定性分析。综合风险评价研究结果表明,生物质气化发电行业处于"较高"的风险等级,与实际情况相符。综合风险评价体系的构建合理,所建立的评价方法以及相应对策分析可为决策者提供参考依据。     

Changes in nitrogen budget and potential risk to the environment over 20 years (1990–2010) in the agroecosystems of the Haihe Basin,China

The nitrogen balance can serve as an indicator of the risk to the environment of nitrogen loss from agricultural land. To investigate the temporal and spatial changes in agricultural nitrogen application and its potential threat to the environment of the Haihe Basin in China, we used a database of county-level agricultural statistics to calculate agricultural nitrogen input, output, surplus intensity, and use efficiency. Chemical fertilizer nitrogen input increased by 51.7% from 1990 to 2000 and by 37.2% from 2000 to 2010, concomitant with increasing crop yields. Simultaneously, the nitrogen surplus intensity increased by 53.5% from 1990 to 2000 and by 16.5% from 2000 to 2010, presenting a continuously increased environmental risk. Nitrogen use efficiency decreased from 0.46 in 1990 to 0.42 in 2000 and remained constant at 0.42 in 2010, partly due to fertilizer composition and type improvement. This level indicates that more than half of nitrogen inputs are lost in agroecosystems. Our results suggest that although the improvement in fertilizer composition and types has partially offset the decrease in nitrogen use efficiency, the environmental risk has still increased gradually over the past 20 years, along with the increase in crop yields and nitrogen application. It is important to achieve a better nitrogen balance through more effective management to significantly reduce the environmental risk, decrease nitrogen surplus intensity, and increase nitrogen use efficiency without sacrificing crop yields.     

Predicted no-effect concentrations for mercury species and ecological risk assessment for mercury pollution in aquatic environment

Mercury(Hg) exists in different chemical forms presenting varied toxic potentials. It is necessary to explore an ecological risk assessment method for different mercury species in aquatic environment. The predicted no-effect concentrations(PNECs) for Hg(Ⅱ) and methyl mercury(Me Hg) in the aqueous phase, calculated using the species sensitivity distribution method and the assessment factor method, were 0.39 and 6.5 × 10-3μg/L, respectively. The partition theory of Hg between sediment and aqueous phases was considered, along with PNECs for the aqueous phase to conduct an ecological risk assessment for Hg in the sediment phase. Two case studies, one in China and one in the Western Black Sea, were conducted using these PNECs. The toxicity of mercury is heavily dependent on their forms,and their potential ecological risk should be respectively evaluated on the basis of mercury species.     

Excretion of manure-borne estrogens and androgens and their potential risk estimation in the Yangtze River Basin

The Yangtze River is the longest river in China, and the river basin spans one fifth of the area of the whole country. Based on statistical data, the excretion of manure-borne steroid hormones, including steroid estrogens(SEs) and steroid androgens(SAs), in 10 provinces of China within the region has been estimated. The potential environmental and ecological risk of manure-borne steroid estrogens to the surface water in this region was also assessed. The manure-borne SE and SA excretions in the 10 provinces and municipalities vary in the order: Sichuan Hunan Hubei Yunnan Jiangsu Anhui Jiangxi Chongqing Qinghai Shanghai. The highest increase of manure-borne SEs(1434.3 kg)and SAs(408.5 kg) was found in Hunan and Hubei provinces, respectively, and the total excretion in 2013 was 65% more than 15 years earlier in these two provinces. However, the emissions in Anhui and Shanghai decreased in this 15 year period of time. Swine urine,chicken feces, cattle urine, and laying hen feces were considered the dominant sources of manure-borne E1, βE2, αE2, and SAs, respectively. Although Jiangsu province did not have the largest excretion of manure-borne SEs, it had the highest level of predicted17β-estradiol equivalency(EEQs) value of 16.65 ng/L in surface water because of the limited surface water resources. According to the lowest observable effect level of 10 ng/L for17β-estradiol, the manure-borne SEs in Jiangsu province might potentially pose ecological risk to its wild aquatic organisms.     

基于情景信息扩散模型的雾霾社会风险演化仿真研究

雾霾灾害不仅危害公众健康,且风险信息的传播会引发社会次级风险。为了研究社会风险信息的扩散演化趋势,本文构建了雾霾社会风险的情景信息扩散模型。以中国2013年雾霾灾害为例,将风险信息扩散过程分为爆发期、扩散期和稳定期,分析了不同参数条件下的信息扩散规律。结果表明,政府应在风险信息爆发期和扩散期增大官方渠道信息的覆盖范围,尤其在爆发期需对自由渠道发布的信息进行严格监管,在社会风险扩大之前制定应对策略。     

典型印染废水处理过程中芳香烃化合物的污染特征及污泥生态风险评价

采用GC-MS测定了典型综合印染废水处理厂废水和污泥中芳香烃化合物的含量.结果表明,原水中苯系物总量为203.96±15.18μg·L-1,其中二甲苯占62.7%,尾水中苯系物总量为0.2±0.029μg·L-1,整个处理工艺对苯系物的去除效率为99%.原水中多环芳烃(PAHs)总浓度达1349.51±35.77 ng·L-1,以3—6环为主,主要富集在颗粒物上.整个工艺对PAHs的去除效率为95%,尾水中PAHs总浓度为65.81±20.99ng·L-1,以2—3环为主.干污泥中PAHs含量高达2996.10±151.0 ng·g-1,污泥吸附为水相中PAHs去除的主要机理之一.印染污泥直接填埋或农用会引起潜在的生态危害.     

水环境中的碘化X-射线造影剂及其去除工艺研究进展

碘化X-射线造影剂(Iodinated X-ray contrast media,ICM)在水环境中被广泛检出,因其近期被发现是碘化消毒副产物的前体物而受到越来越多的关注.本文总结了ICM在污水、地表水和饮用水等水环境中的污染现状;分析了ICM的转化产物及转化机制;重点介绍了ICM的去除工艺,包括高级氧化技术、辐射技术以及生物降解转化技术;讨论了ICM及其降解转化产物可能对环境造成的生态风险.最后,本文对未来ICM的研究前景进行了展望.     

饮用水细菌内毒素污染的风险识别与分析研究进展

细菌内毒素,又称脂多糖分子或者热原,是革兰氏阴性细菌和某些蓝藻细胞壁组分,主要由菌体死亡解体后释放.内毒素是常见的外源性致热原,属于强免疫刺激剂,与多种人类疾病密切相关.由于饮用水中会滋长微生物,因此内毒素污染在饮用水中普遍存在.近年来,国外研究中饮用水的细菌内毒素污染开始受到关注,成为饮用水微生物安全领域新兴的研究方向.本文概述了细菌内毒素的物化性质和生物活性,分析了细菌内毒素在饮用水中的存在形态,综述了国内外关于地表水源、地下水源、管网末梢水和深度处理水的内毒素污染调查状况,分析了传统水处理技术、深度处理技术和饮用水消毒技术对内毒素的控制效果,探讨了饮用水中内毒素的血液暴露、呼吸暴露和胃肠暴露途径导致机体潜在的健康风险、安全阈值和相关标准,并对饮用水细菌内毒素污染研究方向进行了展望.