珠江三角洲淡水养殖沉积物及鱼体中DDTs和PAHs的残留与风险分析

采用GC-ECD和GC-MS分析了珠江三角洲淡水养殖鱼塘沉积物及鱼体中DDTs、PAHs的质量分数。结果表明,珠江三角洲地区鱼塘积物中DDTs质量分数范围为2.87～8.25ng·g-1,PAHs质量分数分布在61.76～196.05ng·g-1(干物质量)之间;鳙鱼、草鱼等5种鱼肌肉样品中DDTs质量分数为5.47～125.27ng·g-(1湿质量),PAHs质量分数为30.94～410.06ng·g-1(湿质量),5个品种鱼体内DDTs质量分数均未超过国家食用卫生标准。部分鱼塘中含有o,p’-DDT和p,p'-DDT,表明近期曾受到DDT污染。生态风险分析表明,珠江三角洲部分地区DDTs污染生态风险较高。     

滴滴涕类农药在广东省鱼类中的残留及人体暴露水平初步评价

检测了采自广东省13个城市水产市场和超市的390个鱼样品中滴滴涕类农药(DDT)及其代谢物(包括o,p’-DDE,p,p’-DDE,o,p’-DDD,p,p’-DDD,o,p’-DDT,p,p’-DDT)的残留浓度.鱼体中DDTs的含量为8.7￣18002ng·g-1(脂肪重)或0.1￣698.9ng·g-1(湿重).不同鱼类之间因生活环境和生活习性的不同,而使其DDTs含量存在较大差别.与我国鱼类食品中DDTs的残留标准相比,仅有2个样品中的DDTs含量水平超过此标准,约占样品总数的0.51%,而超过欧盟水产品标准和美国环境保护局(EPA)标准的样品分别占13.8%和30.5%.广东省居民通过鱼类消费每天DDTs的摄入量为30.8ng·kgbodyweight-1·day-1,仅占FAO/WHO每日允许摄入量的0.3%,但高于其他国家或地区.     

胶州湾某水域蛤蜊(Ruditapes philippinarum)、牡蛎(Crassostrea ariakensis)中的雌激素含量

为了探讨海洋贝类对环境中雌激素的富集情况,采用液-液萃取和固相萃取方法提取了胶州湾李村河入海口蛤蜊、牡蛎和底泥中的雌酮(E1)、雌二醇(E2)、雌三醇(E3)和雌炔醇(EE2),并用GC-MS方法测定了上述4种物质的含量,此外还采用暴露实验方法研究了蛤蜊吸收底泥中雌激素物质的影响因素.测定结果显示,该水域中蛤蜊全组织中E1含量为0.45～5.20ng·g-1,E2含量为nd～4.34ng·g-1,E3和EE2未检出;牡蛎体内的E1、E2和E3含量分别为4.64～29.66、2.16～7.20和0.96～7.96ng·g-1,EE2未检出;底泥中E1、E2和E3含量分别为0.43～2.36、nd～0.59、0.52～1.13ng·g-1,EE2未检出.蛤蜊和牡蛎体内的雌激素物质含量高于其栖息的底泥.暴露实验结果显示,随着底泥中雌激素物质含量的增加或暴露时间增加,蛤蜊体内雌激素物质的含量增加,贝类可吸收并富集底泥中的雌激素物质.     

煤矸石污染水域和天然水域Cd元素在鲫鱼组织中的沉积规律

煤矸石是采煤和洗煤过程中排放的固体废物,其中含有大量的重金属元素Cd,煤矸石的无序排放不仅对环境造成了污染,而且也对人体健康和食品安全构成了严重的威胁。研究商丘永城采煤塌陷区煤矸石污染水域Cd在鱼体中的沉积规律,可为进一步研究Cd污染对鱼类的危害和对煤矸石污染水域鱼肉食品安全的评估奠定基础。本试验采用火焰原子吸收法测定了煤矸石污染水域和天然无污染水域鲫鱼各个组织中Cd的含量。结果表明,(1)塌陷区煤矸石污染水域鲫鱼(Carassius auratus)的鳃、心脏、肌肉中Cd含量分别为1.063 0±0.278 4、8.638 9±3.230 1、1.146 1±0.204 6μg·g-1均高于无污染天然水域鲫鱼相应组织的含量,其中鳃、肌肉中Cd含量显著高于对照组(P0.05)。(2)天然水域中,Cd在鲫鱼体内的含量规律为:肝脏心脏肌肉鳃,但是各组织间的含量差异不显著;而煤矸石污染水域中,Cd在鲫鱼体内沉积规律是:心脏肌肉肝脏鳃,心脏中的含量远远高于其他组织。(3)一个成人每周可安全食用这两个水域的鱼肉量分别为823、365 g;若超过此含量,将存在着潜在健康威胁。结论:煤矿石污染水域鳃、肌肉组织中Cd含量远远高于天然水域,Cd更易沉积在鲫鱼的心脏组织中,每周食用煤矸石污染水域鱼肉365 g以上就存在着健康威胁。     

浑河野生鲫鱼体内重金属污染水平与金属硫蛋白基因表达

为揭示浑河重金属污染的潜在生态风险,分析测定了浑河野生鲫鱼体内重金属的残留水平以及肝和鳃组织中金属硫蛋白基因表达.对鱼体各组织中Cr、Cd、Pb、Cu和Zn含量的分析结果显示,各组织重金属含量的排序为肠＞肝＞鳃＞肌肉,且Zn含量最高(17.49～ 176.01 mg·kg-1,以湿体质量计算),Cd含量最低(N.D.～...     

两种喂食方式下微囊藻毒素-LR在罗非鱼肝脏和肌肉中动态变化的比较(Dynamical Response of Microcystins-LR in Liver and Muscle of Tilapia（Oreochromis niloticus）in Two Feeding Conditions of Cyanobacteria)

试验以尼罗罗非鱼作为受试动物,通过直接投喂未经处理的新鲜藻细胞和喂食相同量经超声波破碎过的藻细胞,比较了罗非鱼在摄食完整蓝藻细胞与摄食破碎的蓝藻细胞时微囊藻毒素-LR（MC-LR）在其体内的动态变化规律及代谢差异. 结果表明,无论是喂食破碎蓝藻细胞还是未破碎的蓝藻细胞均可在罗非鱼肝脏和肌肉中检出MC-LR,细胞破碎组肝脏和肌肉的富集能力高于未破碎组. 富集第3d,即可在肝脏和肌肉中检出不同程度的MC-LR,肝脏中MC-LR的含量显著高于肌肉,随着富集时间的延长,MC-LR的含量总体呈上升趋势,破碎组肝脏和肌肉分别在染毒的16d和11d达到最大值（分别为2.021μg·g-1和0.071μg·g-1）;未破碎组则分别在染毒的24d和21d达到最大值（分别为1.856μg·g-1和0.036μg·g-1）. 整个富集阶段破碎组肝脏MC-LR的平均值为1.171μg·g-1,略高于未破碎组的1.029μg·g-1;破碎组肌肉含量的平均值0.051μg·g-1,高于未破碎组的0.029μg·g-1. 将细胞未破碎组的罗非鱼进行释放阶段的试验. 结果表明,罗非鱼的肝脏能快速清除MC-LR,释放13d时达到释放阶段的最低值（为0.241μg·g-1）,与肝脏相比,肌肉对毒素的清除要缓慢得多.     

两种喂食方式下微囊藻毒素-LR在罗非鱼肝脏和肌肉中动态变化的比较

试验以尼罗罗非鱼作为受试动物,通过直接投喂未经处理的新鲜藻细胞和喂食相同量经超声波破碎过的藻细胞,比较了罗非鱼在摄食完整蓝藻细胞与摄食破碎的蓝藻细胞时微囊藻毒素-LR(MC-LR)在其体内的动态变化规律及代谢差异.结果表明,无论是喂食破碎蓝藻细胞还是未破碎的蓝藻细胞均可在罗非鱼肝脏和肌肉中检出MC-LR,细胞破碎组肝脏和肌肉的富集能力高于未破碎组.富集第3d,即可在肝脏和肌肉中检出不同程度的MC-LR,肝脏中MC-LR的含量显著高于肌肉,随着富集时间的延长,MC-LR的含量总体呈上升趋势,破碎组肝脏和肌肉分别在染毒的16d和11d达到最大值(分别为2.021μg·g-1和0.071μg·g-1);未破碎组则分别在染毒的24d和21d达到最大值(分别为1.856μg·g-1和0.036μg·g-1).整个富集阶段破碎组肝脏MC-LR的平均值为1.171μg·g-1,略高于未破碎组的1.029μg·g-1;破碎组肌肉含量的平均值0.051μg·g-1,高于未破碎组的0.029μg·g-1.将细胞未破碎组的罗非鱼进行释放阶段的试验.结果表明,罗非鱼的肝脏能快速清除MC-LR,释放13d时达到释放阶段的最低值(为0.241μg·g-1),与肝脏相比,肌肉对毒素的清除要缓慢得多.     

环渤海北部沿海地区表层土壤中PAHs的污染特征及风险评价

系统采集了环渤海北部沿海地区31个表层土壤样品,利用GC/MS分析了16种USEPA优控多环芳烃(PAHs)的含量和组分特征,运用主成分因子载荷法揭示了其污染来源,并初步评价了其风险水平.结果表明,沿海地区65%的土壤已被污染,最高污染样点PAHs含量达920.4ng·g-1,平均含量309.5ng·g-1,与国内外相关研究比较,处于中低等污染水平.各类燃料的不完全燃烧是该地区土壤中PAHs的主要来源,石油类挥发或泄漏对采油区土壤中PAHs的累积影响显著.     

乌鲁木齐市水磨河底泥及污灌区土壤中有机氯农药的分布

用GC-ECD定量测定了乌鲁木齐市水磨河底泥及污灌区土壤中有机氯农药的含量.结果表明:底泥样品中HCHs和DDTs的含量为0.107-111.69ng·g-1和0.476-66.512ng·g-1,有机氯农药总量为0.583-178.202ng·g-1;土壤中为0.194-6.974ng·g-1和0.520-10.438ng·g-1,有机氯农药总量为0.714-17.412ng·g-1.底泥中HCHs的α/γ比值约为4,底泥和土壤中DDT/(DDE DDD)的比值较大.     

太原市污灌区地表土中有机氯农药分布特征

为了研究太原市污灌区地表土中有机氯农药(OCPs)分布特征,本文在太原小店区共采集了31个地表土样,应用气相色谱-电子捕获检测器(GC-ECD)检测土壤中OCPs的含量.结果表明,研究区地表土中OCPs污染较轻,总OCPs浓度范围为2.01—47.20 ng.g-1(平均值为16.76 ng.g-1).其中总滴滴涕(∑DDT)浓度范围为0.27—37.93 ng.g-1(平均值为8.38 ng.g-1),总六六六(∑HCH)浓度范围为0.18—11.89 ng.g-1(平均值为3.37 ng.g-1),最高浓度均没有超过《土壤环境质量标准》(GB15618—1995)中的Ⅱ级标准(农业土地).不同灌溉区OCPs浓度平均值顺序为:污灌区>清灌区>背景点,表明污水回灌对OCPs浓度分布具有一定的影响,同时通过比较各采样点中OCPs各异构体的组成发现,该区域HCHs、DDTs和硫丹农药主要来自于历史残留,部分区域曾使用林丹和三氯杀螨醇农药.对比各有机氯农药浓度地理分布特征,表明OCPs浓度分布与污水灌溉存在一定的联系.     

Cadmium,copper, and zinc in carrots in Japan

Cadmium (Cd), copper (Cu), and zinc (Zn) in carrots obtained from different regions throughout Japan were assessed in a baseline study on the contents of trace metals in foods. These three metals were measured by flameless atomic absorption spectrophotometry. The geometric mean contents (with one geometric standard deviation indicated in parentheses) of Cd, Cu, and Zn were 0.02 (2.2), 0.7 (2.1), and 2.4 (1.6) mg?kg^?1 wet weight in carrots obtained in Japan. While there was a close relationship among the contents of the three metals in the carrots grown in Cambisols and Gleysols, a significant relationship was recognized only between the contents of Cd and Zn in those grown in Andosols and Fluvic Gleysols. Cd and Zn are classified as 2B metals in the periodic table of elements, and the authors speculate that the similarity of the metal characteristics between Cd and Zn may be responsible for the close relationship in the contents of the two metals, with no relation to the soil type.     

Geochemical anomalies in two sulfide-bearing waste disposal areas: Fe,Cu, Zn,Cd, Pb,and As in contaminated waters and snow,Kemerovo and Chelyabinsk regions,Russia

Sulfide-bearing mill wastes are sources of high concentrations of acid, soluble metals, Sb, and As. Contents of Cu, Zn, Fe, Pb, Cd, As, and Sb in wastes of the Belovo Zn-processing and the Karabash mineral-processing plants (Russia) exceed the average content in the upper continental crust and background soils. High-dissolved metal and As concentrations are found in acid drainages, which form as a result of interaction between sulfide wastes and water. Monitoring research using geochemical and geophysical methods was performed to evaluate the contamination of the surrounding area (water and bottom sediments in the contaminated rivers and snow cover). Zones of geochemical anomalies were identified where the concentrations of Fe, Cu, Zn, Cd, Pb, and As are 2–3 orders of magnitude higher than in drinking water standards (for rivers) and background levels (for snow). The use of geophysical methods allowed us to prove penetration of drainage solutions into the groundwaters. The total environmental damage caused by the pollution of water and land resources in the Belovo Zn-processing plant waste disposal area amounted to $156 million at the time of 2011, and could reach $480 million by 2030, if steps are not taken in recycling and remediation of disturbed areas.     

Applications of chitosan in food,pharmaceuticals, medicine,cosmetics, agriculture,textiles, pulp and paper,biotechnology, and environmental chemistry

Environmental Chemistry Letters - Chitosan is a biopolymer obtained from chitin, one of the most abundant and renewable materials on Earth. Chitin is a primary component of cell walls in fungi, the...     

Occurrence,distribution and dynamics of perchlorate in soil,water, fertilizers,vegetables and fruits and associated human exposure in Chile

Environmental Geochemistry and Health - Perchlorate (ClO4?) has been identified as a persistent environmental contaminant of concern. Perchlorate exposure is a potential health concern...     

Energy,population, and agricultural productivity in Iran

Solar energy feeds all life on this planet's surface. The energy of the Sun can be tapped and converted to the different forms of energy by renewable energy systems, such as solar power plants, photovoltaic systems, and plants. Land is needed for food production, which is the most globally important activity. With increasing population, the required area is determined by consumption and production patterns. The world is globally divided into poor and rich areas of production and consumption, which have large differences. Iran's energy and food production and consumption are studied and compare with poor and rich examples. It is concluded that available agricultural land is limited and currently declining per capita due to population growth. The expansion of irrigated crop area, high-quality seed, and modern farming techniques can marginally improve agricultural productivity and provide relative self-sufficiency in grain production. Much of the growth in Iran's renewable energy is attributed to hydroelectricity power plants. Solar energy, wind, hydro and geothermal energy are also potential forms of sustainable energy in Iran.     

Cd,Pb, and Cu in water and sediments and their bioaccumulation in freshwater fish of some lakes in Hanoi,Vietnam

The seasonal variations of Cd, Pb, and Cu in the water, sediments, and freshwater fish (Hypophthalmichthys molitrix, Cirrhinus molitorella, and Oreochromis mossambicus) of four lakes in Hanoi, Vietnam, were investigated. Samples for analysis were taken four times from April 2010 to March 2011. The levels in water were lower than the Vietnamese standards, except for Pb, but they were all much higher than the Canadian standards for protection of aquatic life; in the sediments, they were higher than world average levels. Bioaccumulation of the three metals in fish was site-dependent and species-dependent, but correlations of their levels in fish to those in water and sediments were weak. Levels of Pb in fish exceeded those of the UK and the WHO standards, and the recommended values of Vietnam for human consumption. Overall, the results show that the lakes are polluted with these metals, and consumption of high quantities of fish from them may be problematic. The outcome of this research helps to establish background data for future monitoring.     

MHC, health, color, and reproductive success in sand lizards

Good genes are genetic elements that contribute to lifetime reproductive success, regardless of an individuals additional genotype. Their existence is debated, and most work has targeted their viability benefits to the offspring of choosy females. In the present study, we analyze a case of potential good genes effects in adult male sand lizards (Lacerta agilis). We show that males with a particular RFLP (Restriction Fragment Length Polymorphism) MHC genotype (O-males), as opposed to those that lack this genetic element (NO-males), have less ectoparasites under increasing physiological stress (indexed by baseline corticosterone level), and are not constrained by parasites at production of status coloration. Furthermore, O-males are more successful at mate acquisition and guard their partners longer. Ultimately, they have a higher genetic reproductive success as assigned by microsatellites.Communicated by W. Cooper     

Lead,cadmium, copper,zinc, iron,and calcium in human hair as a function of gender,age, smoking,and hair dyeing

Hair samples were collected randomly from 110 subjects (55 male and 55 female) ranging in age from (<15–60) years. Each subject was asked to complete a personal questionnaire describing his/her sex, age, general health, smoking, use of hair dyes, occupational area, and living habits. Concentrations of Pb, Cd, Cu, Zn, Fe, and Ca in human hair samples were evaluated using atomic absorption spectrometry. Results indicated that concentrations of Pb, Cd, Cu, and Zn in the hair of smokers were higher than those in the hair of non-smokers, whereas, Fe and Ca concentrations in hair of smokers were lower than those in hair of non-smokers. Moreover, the concentrations of these elements are higher in dyed hair compared with undyed hair.