Mercury concentration in the muscle of seven fish species from Chagan Lake,Northeast China

Chagan Lake is located downstream of the Second Songhua River basin in Northeast China. It is one of the top ten inland freshwater lakes, and an important aquatic farm in China. The lake has been receiving large amounts (currently at 1.5 × 10⁸ m³/a) of water from the river since 1984. This would pose a threat to the aquatic system of the lake because the river was seriously polluted with mercury in 1970s–1980s. The current study is the first to report the total mercury concentrations in fish found in the lake. Mercury concentrations in seven fish species collected from the lake in January 2009 were determined. The related human health risk from fish consumption was also assessed. The average concentration of mercury in the fish was 18.8 μg/kg of wet weight, ranging from 4.5 to 37.6 μg/kg of wet weight. A large difference in the mercury concentrations among the fish species was found. The mercury concentration was found to be higher in carnivorous species and lower in omnivorous and herbivorous species. This demonstrates greater mercury bioaccumulation in fish species at higher trophic levels. Mercury concentrations in fish showed significant positive correlations with age, length, and weight. No significant relationship was found between mercury concentrations in fish and the habitat preferences. Mercury concentrations in fish from the lake were within the limits of the international and national standards of China established for mercury. According to the reference doses established by the United States Environmental Protection Agency, the maximum safe consuming quantity considering all the fish was 297.3 g/day/person, which was more than five times as much as the current quantity (50 g/day/person) consumed by the local residents. This investigation indicates that the historical pollution of the Second Songhua River has not caused mercury bioaccumulation in fish muscle tissue of Chagan Lake. The present consumption of fish from the lake in the local area does not pose a threat to human health.     

北方沙尘对四川盆地环境空气质量影响和特征分析

利用沙尘天气资料和颗粒物浓度、激光雷达监测数据以及后向轨迹,分析浮尘天气的气象特征及传输路径,构建了浮尘天气对四川盆地各城市大气环境质量影响的量化指标,并利用该量化指标分析了浮尘天气对四川盆地各城市大气环境的影响,得出2013—2015年浮尘对四川盆地PM_(10)年均质量浓度的贡献,2013—2015年约为4.82、1.00、0.56μg/m~3;浮尘对PM_(10)年均质量浓度的贡献川西区域最大,川东北区域次之,川中区域最小,其贡献量分别为3.5、2.2、1.4μg/m~3。同时还进一步分析浮尘对区域PM_(10)影响差异的原因。     

Natural and anthropogenic factors affecting the shallow groundwater quality in a typical irrigation area with reclaimed water,North China Plain

In this study, the hydrochemical characteristics of shallow groundwater were analyzed to get insight into the factors affecting groundwater quality in a typical agricultural dominated area of the North China Plain. Forty-four shallow groundwater samples were collected for chemical analysis. The water type changes from Ca·Na-HCO₃ type in grass land to Ca·Na-Cl (+NO₃) type and Na (Ca)-Cl (+NO₃+SO₄) type in construction and facility agricultural land, indicating the influence of human activities. The factor analysis and geostatistical analysis revealed that the two major factors contributing to the groundwater hydrochemical compositions were the water-rock interaction and contamination from sewage discharge and agricultural fertilizers. The major ions (F, HCO₃) and trace element (As) in the shallow groundwater represented the natural origin, while the nitrate and sulfate concentrations were related to the application of fertilizer and sewage discharge in the facility agricultural area, which was mainly affected by the human activities. The values of pH, total dissolved solids, electric conductivity, and conventional component (K, Ca, Na, Mg, Cl) in shallow groundwater increased from grass land and cultivated land, to construction land and to facility agriculture which were originated from the combination sources of natural processes (e.g., water-rock interaction) and human activities (e.g., domestic effluents). The study indicated that both natural processes and human activities had influences on the groundwater hydrochemical compositions in shallow groundwater, while anthropogenic processes had more contribution, especially in the reclaimed water irrigation area.     

楼顶式移动基站电磁辐射污染调查

对南通市楼顶式移动基站电磁辐射污染进行了调查。结果表明,南通市418个楼顶站基站周边地面50 m范围内电磁辐射功率密度值均能满足《电磁环境控制限值》(GB 8702—2014)的要求;楼顶美化天线、集束天线和景观塔等建设较晚的楼顶塔形地面电磁辐射强度相对较小,楼顶角钢塔、拉线塔和抱杆等建设较早的塔形地面电磁辐射强度相对较大;楼顶塔所在楼顶平台监测值存在轻度超标的情况。提出,应严格控制楼顶塔所在楼顶的人员可达性,即基站电磁辐射防护区应高出楼顶2 m以上,避免公众进入基站电磁辐射防护区内,受到基站天线的过量辐射影响。     

多组学技术应用于化学品风险评估的研究进展

随着进入到环境中的化学品种类和数量日益增加,化学品风险评估面临着越来越大的挑战.传统的化学品风险评估方法依赖于动物实验,无法对大量化学品的毒性进行高效检验与预测,并且缺少对机制的研究.多组学技术是多种高通量组学技术的联合应用,主要包括基因组学、转录组学、蛋白质组学和代谢组学等,可以更加快速、准确地分析化学品毒性,预测化...     

“双碳”背景下工业源VOCs排放特征与减排潜力研究

运用排放因子法估算2020年工业源VOCs排放量,综合相关文献调研结果、环境空气质量和“双碳”相关政策要求、技术发展规律以及专家评估,运用情景分析法确定排放源减排措施、排放因子减排率、能效提升率并量化2020—2060年强化情景和双碳情景的排放量和减排潜力,同时分析CO2和VOCs减排的协同效应.结果表明,2020年工业源VOCs排放量约为1357.5万t.含VOCs的产品使用环节排放量最大,占总量的55.7%.工业防护涂料涂装、印刷与包装印刷及石油和天然气加工为前3大排放量源,合计贡献率约为34.7%.江苏、山东、广东、浙江是全国前4大排放省份,共占全国总排放量的40.7%.4种控制情景下,2060年高速GDP-强化情景排放量最大,约为532万t;低速GDP-双碳情景最小,约469万t,相比于高速GDP-强化情景排放量减少63万t,表明双碳政策有利于VOCs减排;排放量减排率方面,2020—2040年高速GDP-双碳情景减排率小于低速GDP-强化情景,2040—2060年反之,表明双碳政策更有利于VOCs的中长期减排.环节方面,含VOCs产品的使用排放占比变化最大,2060年双碳情景...     

西南喀斯特地区典型矿渣中砷、锑的赋存形态及其潜在风险评价

针对西南喀斯特地区典型矿渣中砷、锑的赋存形态及其潜在风险的问题,采用Shiowatana连续提取法提取矿渣中的砷（As）、锑（Sb）,分析并揭示As、Sb的赋存特征;结合矿渣的基本理化性质和矿物组成特征,讨论矿渣堆中As、Sb的活动性及其关键影响因素;采用风险评价编码法（RAC）对矿渣中As、Sb的潜在生态风险进行相关评价.结果表明：矿渣中的As主要以铁铝结合态和残渣态的形式赋存;Sb主要以残渣态的形式赋存.As比Sb具有更高比例的铁铝结合态,而Sb比As具有更高比例的碳酸盐结合态.弱酸至近中性矿渣中,Sb的活动性强于As;酸性矿渣中,As的活动性强于Sb.矿渣中As、Sb的潜在风险以中-低风险为主,个别为高和极高风险.     

Quantifying groundwater phosphorus flux to rivers in a typical agricultural watershed in eastern China

Environmental Science and Pollution Research - Increasing evidence indicates that groundwater can contain high dissolved phosphorus (P) concentrations, thereby contributing as a potential pollution...     

Adsorption performance and mechanisms of mercaptans removal from gasoline oil using core-shell AC-based adsorbents

Environmental Science and Pollution Research - Sulfur compound detection such as mercaptans in liquid fuels is undesirable because sulfur is the main sourcing emission of sulfur oxide (SOx) into...     

超亲水石墨烯/二氧化硅复合膜的制备优化和表征

膜表面亲水性是主导膜污染发生的关键因素,亲水膜的抗污染能力较强。基于氧化石墨烯(GO)和氨基修饰的纳米SiO_2之间的自组装反应,分别通过真空抽滤、多巴胺辅助抽滤、热辅助法以及高温煅烧辅助抽滤法制备了多种GO/SiO_2复合膜,结合纯水接触角测定、表面官能团分析以及电镜观察等,对制备方法和条件进行了优化。结果表明:高温煅烧法制备的超亲水GO/SiO_2复合膜,其初始接触角为6.1°,并于2 s内,在膜表面实现完全铺展,表现出超亲水特性;此外,所制备的GO/SiO_2超亲水膜的纯水通量分别是传统PVDF超滤膜、超亲水SiO_2/PVDF复合膜和0.22μm有机商业膜的3.21、11.10和1.22倍,显示出良好的应用潜力。