Evaluation of the possible adverse effects of legacy persistent organic pollutants (POPs) on the brown booby (Sula leucogaster) along the Brazilian coast

This study aimed to investigate the impact of contamination by persistent organic pollutants (POPs) on Brazilian wildlife. The concentrations of certain POPs, including dichlorodiphenyltrichloroethane (DDT) and polychlorinated biphenyls (PCBs), in the eggs of the brown booby (Sula leucogaster) were measured. The eggs were collected from breeding colonies located on three archipelagos (Saint Peter and Saint Paul, Abrolhos and Cagarras Islands) in the Atlantic Ocean, which are located at different distances from the Brazilian coast (range 4-1010 km). In addition, possible alterations in eggshell characteristics were evaluated. The average values of POPs found in eggs from the archipelago of Saint Peter and Saint Paul (0.05 μg g⁻¹ of ΣPCBs and 0.01 μg g⁻¹ of ΣDDT) and the archipelago of Abrolhos (0.19 μg g⁻¹ of ΣPCBs and 0.03 μg g⁻¹ of ΣDDT) were low compared to the reference values reported in the literature. In contrast, the concentrations measured in eggs from Cagarras (8.4 μg g⁻¹ of ΣPCBs and 1.8 μg g⁻¹ of ΣDDT) were the highest, and this total PCB level is close to the threshold values considered to be harmful to birds. Our findings indicate that the brown booby colony closest to the Rio de Janeiro coast has recently been exposed to DDT. Despite the high pollution levels found on the Cagarras Islands, no alterations in the eggshell weight or the thickness of the analyzed eggs were detected. Hence, more detailed studies are recommended to determine the actual effects of the selected POPs on the Cagarras breeding colony.     

Heavy metal induced ecological risk in the city of Urumqi, NW China

A total of 169 samples of road dust collected in the city of Urumqi, capital of the Xinjiang Uygur Autonomous Region in northwest China, were analyzed by method of inductively coupled plasma-mass spectrometry for 10 elements (i.e., Cd, Cr, Cu, Ni, Pb, Mn, Be, Co, Zn, and U). The possible sources of metals are identified with multivariate analysis such as correlation analysis, principal component analysis, and cluster analysis. Besides, enrichment factors are used to quantitatively evaluate the influences of human activities on heavy metal concentrations. Moreover, the potential ecological risk index is applied to evaluating the ecological risk of heavy metal pollutants. The results indicate that: (1) the concentrations of the heavy metals involved were much higher in urban areas than the background values, except those of Co and U. Mn, U, and Co are mainly of natural origin; Cu, Pb, Zn, and Cr are mainly of traffic sources and are partly of industrial sources; Ni and Be are mainly the results of industrial activities, such as machine shops, firepower plants, tire and rubber factories, cement factories, and textile mills and are partly of the traffic sources; (2) with high “toxic-response” factor and high concentration, Cd has more serious influences on the environment than other heavy metals. Therefore, commercial and industrial areas are usually characterized by higher potential ecological risk when compared with residential areas and new developing urban areas. The results of this study could be helpful for the management of environment in industrial areas.     

金城造纸厂综合污水处理工程调试运行

总结了采用好氧工艺处理造纸工业废水中各个不同调试阶段及对应的工艺运行参数。该废水难生化降解,其ρ(BOD5)/ρ(COD)值在23.3%左右,而且废水中N、P等营养元素含量不足。通过投加尿素和磷酸氢二氨,使均质池TN、TP含量满足微生物生长;同时降低进水ρ(COD)值至1500mg/L,提高曝气池溶解氧量至3.0mg/L,污泥浓度至4500mg/L,将COD污泥负荷从最初0.45～0.55kg/(kg·d)逐渐下降到0.30～0.35kg/(kg·d),经过2个月的调试运行,出水各参数达到设计排放标准:COD为450mg/L、BOD5为25mg/L、pH为6.8。     

落叶阔叶树异戊二烯排放研究

采用封闭式采样方法及光离子化气体分析仪直接分析技术测定了１２种北京市主要绿化树种的异戊二烯排放速率。结果表明：法国梧桐,龙爪槐、杨树和柳树为强异戊二烯排放树种;     

《海水水质标准(GB3097—1997)》定值的合理性浅析——以铅和甲基对硫磷为例

基于物种敏感度分布曲线法,推导了铅和甲基对硫磷的海水水质基准低值和高值,并与《海水水质标准(GB 3097—1997)》中铅和甲基对硫磷的相关标准限值进行了比较,结果表明目前尚缺乏充分的科学证据说明我国现行的海水水质标准可以为我国海洋环境中大多数水生生物提供适当的保护,不同污染物的标准定值存在着一定程度的"欠保护"和"过保护"的问题。此外,结合我国近岸海水水质监测资料,在剖析了海水水质标准定值的合理性的基础上,对我国今后的海水水质基准和标准的研究进行了展望,给出了相应的对策和建议。     

超声波/紫外线-Fenton反应联用去除克拉玛依土壤中石油类污染物

研究了超声波(ultrasonic)和紫外线(ultraviolet)-Fenton反应联用处理干旱区老化石油污染土壤。土壤TPH含量为30 470 mg/kg,pH值为3,H2O2与Fe比例为50∶1时,H2O2浓度为0.37%、0.74%、1.11%和1.85%在超声波处理6 h土壤TPH去除量分别为4 495、11 983、15 470和19 800 mg/kg;TPH去除量随H2O2/Fe2+增大而增大,H2O2/Fe2+为100∶1时,TPH去除量为12 699 mg/kg。溶液pH值接近中性,H2O2浓度为0.74%,H2O2/Fe2+为50∶1,超声波与UV共同作用2 h和4 h,TPH去除量分别达到14 824和21 821 mg/kg;UV单独作用2 h、4 h对土壤TPH去除量为9 253和12 845 mg/kg。超声波-Fenton反应对1,2-二甲苯降解效果最好,其次为C17-C28的直链及支链烷烃,最低为烃类衍生物。     

Gaps,biases, and future directions in research on the impacts of anthropogenic land-use change on aquatic ecosystems: a topic-based bibliometric analysis

Environmental Science and Pollution Research - Anthropogenic land use change (ALUC) satisfies human needs but also impacts aquatic ecosystems. Aquatic ecosystems are intrinsically linked with...     

把好进口关

化学性食物中毒指有毒的金属、非金属及化合物,农药、亚硝酸盐等化学物质污染的食物而引发食物中毒。如有机磷、亚硝酸盐、砷化物等。预防留存在蔬菜水果表面的农药,应用清水彻底冲洗     

New DDT inputs after 30 years of prohibition in Spain. A case study in agricultural soils from south-western Spain

This study provides information on the current status of contamination by DDT in agricultural soils in south-western Spain. A recent use of technical DDT in at least 17% of the soils was found based on the values (<1) of the ratio Rp,p^′/p,p^′=[p,p^′-DDE+p,p^′-DDD]/[p,p^′-DDT]. According to the ratio Ro,p^′/p,p^′=[o,p^′-DDT]/[p,p^′-DDT], a dicofol type contamination was detected in about 27% of the soils. A wide range of concentrations was observed (0.08-11.1 ng/g d.w.) regardless of the type of crop soil. Enantiomeric fractions (EFs), based on the chiral analysis of o,p′-DDT residues differed from the racemic value (0.500) in most soils but they were not correlated with the study variables [DDTs], SOM, Rp,p^′/p,p^′ and Ro,p^′/p,p^′. Given the health risks posed by DDT, our findings support how the environmental control of legacy pollutants such as DDT cannot be neglected.     

水体低氧的早期暴露对青鳉(Oryzias latipes)后期的生长、性别比和繁殖能力的影响

水体低氧已是全球性生态问题,常以季节性、偶发性和昼夜间等不同形式存在于不同的水体中。长期低氧可影响鱼类正常的生长和繁殖,但鱼类早期生活阶段暴露于不同形式的低氧后,后期的生长和繁殖是否会受到不利影响,目前研究甚少。本研究在实验室模拟了连续低氧(2.8 mg·L~(-1)DO)(H1)、昼夜低氧(H2)和发生在胚胎器官形成时期的偶发性低氧(H3)等3种情景对青鳉胚胎的发育影响,评估了这一早期暴露对青鳉后期的生长、存活和繁殖的影响。我们发现,3种低氧方式都可以显著延长青鳉胚胎的孵化周期,引起胚胎卵黄囊吸收和鱼鳔发育异常;暴露结束120 d后,H1组青鳉成鱼的畸形率显著升高、存活率和生长速度都显著下降;H1、H2和H3组中成鱼的雌雄比都发生了改变,鱼群中以雄鱼为主,且产卵量和受精率都显著下降。结果表明,鱼类早期胚胎发育阶段所受到的低氧暴露可对后期生长和繁殖产生不利影响,对子代补充和种群稳定产生重要影响;鱼类关键发育期所经历的低氧事件,以及昼夜低氧事件所产生的生态后果不容忽视。