Organochlorine pesticide residues in leek (Allium porrum) crops grown on untreated soils from an agricultural environment

Leek (Allium porrum) plants from organic farming were harvested at 15, 59, and 210 days after seed germination. Organochlorine pesticide (OCP) levels were quantified by GC-ECD in vegetative tissues (roots and aerial), bulk soil and rhizosphere. Leek plant bioaccumulate OCPs efficiently in their aerial and root tissues and alter the concentration of the soil where they are grown. OCPs distribution pattern of bulk soil was endosulfans > DDTs > dieldrin, while it was endosulfans > HCHs > DDTs in leek tissues. There were statistically significant declines in DDTs, chlordane, dieldrin, and heptachlor in the rhizosphere, indicating that recalcitrant residues of OCPs may be removed from contaminated soil using leek crops under normal growing conditions. The DDE/DDT and alpha-/gamma-HCH ratios of < 1 would indicate recent inputs of DDT and lindane in the environment. The occurrence of OCPs in this farm could be the result of atmospheric deposition and/or surface runoff of these pesticides.     

新疆典型农业地区土壤中有机氯农药（OCPs）分布特征及风险评价

为加强有机氯农药(organic chlorinated pesticides,OCPs)的污染预防与控制,该研究分析了新疆典型农业地区有机氯农药的污染状况并对其进行了风险评价。采集表层土壤样品36个,分析其中15种OCPs的残留状况。六六六(Hexachlorocyclohexanes,HCHs)、滴滴涕(dichlorodiphenyltrichloroethanes,DDTs)、氯丹类化合物、硫丹和硫丹盐的质量分数范围分别是0.37～22.82、0.91～858.47、0.15～47.08ng/g、N.D(未检出)～16.27和N.D～73.83ng/g。对OCPs的来源进行分析,发现HCHs来源于历史上工业HCHs的使用或近期林丹的输入,DDT来源于工业品的违法使用和三氯杀螨醇的使用,研究区域氯丹存在新的来源,而硫丹新来源较少。通过主成分分析,从15种OCPs中提取了5个主成分,总方差解释量达到了79.93%。5个主成分分别归因于DDT和工业HCH s的使用、OCPs原料的差异以及研究区域内病虫害的发病特征等。利用灰色关联分析研究区域内OCPs污染状况,结果表明石河子污染水平最高,各研究区域土壤均需要采取进一步的污染控制措施。     

巢湖东半湖沉积物中有机氯农药的残留特征及风险评价

采样测定了巢湖东半湖4个样点的表层沉积物中有机氯农药（OCPs）的含量。结果表明,11种有机氯农药在样品中被检出,总含量为8.26～31.73 ng.g^-1;OCPs在沉积物中的垂直分布从上往下大体呈递减趋势;且OCPs的最高含量都出现在上层沉积物中,说明巢湖东半湖沉积物中有机氯农药主要集中在0-3 cm的表层。根据分析,DDTs来自于早期残留或者施用农药后的长期风化残留。沉积物风险评估表明,巢湖东半湖表层沉积物中的有机氯农药存在一定的生态风险。     

运用红边参数估算叶片叶绿素含量

Soil samples collected from several sites along an altitudinal transect on the eastern slope of the Tibetan Plateau were analyzed for hexachlorobenzenes(HCHs) and dichlorodiphenyltrichloroethanes(DDTs).The results showed that HCHs and DDTs were found in the soil samples from the remote high altitude areas away from source regions,which confirmed the long-range atmospheric transport phenomenon of these organochlorine pesticides(OCPs) insecticides.The OCP concentrations in the soils had a significant negative correlation with altitude;they showed a trend to increase with decreasing altitude,but the increase was not continuous,being interrupted at some moderate-altitude sites on the transect.The distances from the source region,landforms,soil properties,and physical-chemical properties of OCPs were more important than total organic carbon content to the distribution of OCPs in soils disturbed by human activities.An analysis of the compositions of HCH isomers and DDTs revealed predominantly low ratios of α-HCH to γ-HCH,ranging from 0.06 to 4.79,which suggested current lindane inputs.On the other hand,low p,p-DDT/p,p-DDE and o,p-DDT/p,p-DDT ratios were observed,indicating mainly aged historical DDT residues in the study area.     

A miniaturized method for fast,simple, and sensitive pesticide analysis in soils

Journal of Soils and Sediments - Organochlorine pesticides (OCPs) like lindane and DDT have been used extensively after World War II until the 1990s. Still, residues of these pesticides can be...     

~(14)C-丁草胺、~(14)C-毒死蜱和~(14)C-DDT在日本林蛙中的生物学行为(英文)

用同位素示踪技术研究了14 C 丁草胺、14 C 毒死蜱和14 C DDT在日本林蛙 (RanajaponicajaponicaGuenther)中的生物学行为。结果发现 ,14 C 丁草胺、14 C 毒死蜱和14 C DDT在 2 4h后分布到青蛙的各个器官组织 ,并分别以胆囊、小肠、小肠为它们的特异性浓集器官。与胆囊或小肠的14 C放射性活度比较 ,其它器官组织中的要小得多。14C DDT在日本林蛙中较难降解 ,2 4h后DDT母体在肝和脂肪组织中占DDT代谢物的54 6%和 88 4%。青蛙中的14 C 丁草胺、14 C 毒死蜱和14 C DDT可被丙酮提取 ,但三者之间以及在青蛙的器官之间有差异     

大连湾养殖海域有机氯农药污染研究

采用毛细管GC-ECD法测定了大连湾海域表层沉积物及表层、微表层海水中16种有机氯农药(OCP₁₆)的含量。结果表明，毛细管GC-ECD测定OCPs回收率高、响应因子变异系数小、检出限低，适合于海洋环境样品中OCPs测定。在大连湾海域沉积物和水体中对OCPs均有检出，但污染水平相对较低。表层海水中OCPs平均含量为4.52 ng/L，表层沉积物中OCPs平均含量为6.17 ng/g。大连湾各站位微表层海水OCPs含量显著高于表层水，显示微表层海水对OCPs有较强的富集作用，平均富集系数在5.1～15.4之间。     

Composition, Distribution, and Characterization of Organochlorine Pesticides in Sandstorm Depositions in Beijing, China

Sandstorms which distribute a great number of particles are a special atmospheric occurrence and are uncommon in northern China. This study was conducted to determine, for the first time, the concentration of organochlorine pesticides (OCPs) in sandstorm depositions. Samples were collected from urban areas of Beijing and a total of eight OCPs were measured. All samples contained OCP residues. The total hexachlorocyclohexane (HCHs) concentration ranged from 20.6 to 59.8ng g^?1 and the total dichlorodiphenyltrichloroethane (DDTs) concentration ranged from 12.0 to 14.3ng g^?1. Furthermore, increasing HCH contamination was observed from the northwest to the southeast and a uniform distribution of DDT contamination was discovered in Beijing. Analysis of the sources of contamination showed that HCHs in the sandstorm depositions were derived from a relatively old source of lindane, and DDTs mainly originated from an old source of dicofol in Beijing. The preliminary pollution assessment of the samples indicated that HCH levels might be categorized as low pollution and DDT levels might be categorized as no pollution. The present study suggests that sandstorm depositions may not produce the special risk of adverse health effect from OCPs for the residents of Beijing, China.     

铜污染农田表层土壤的持久性有机氯农药残留状况

土壤中持久性有机污染物往往与重金属共存形成混合污染,但过去的研究较少关注它们在土壤中的相互影响。本研究选择典型铜污染区农田,分析了铜不同污染程度的表层土壤中HCB、HCHs与DDTs等持久性有机氯农药的组分及含量。结果表明:DDTs在土壤中的残留量随着土壤铜污染程度的加剧而上升;土壤中铜抑止了DDT向DDE或DDD的转化,DDTs残留量相对较大。供试土壤中持久性有机氯农药含量与有机质之间的相关性分析表明,污染土壤中两者之间的相关性大于未污染土壤,说明铜促进了土壤中的DDTs和HCHs与土壤有机质结合,这可能是导致水田土壤中DDTs的平均含量显著高于旱地和林灌地土壤的原因之一。     

Selected persistent organic pollutants (POPs) in the rhizosphere of sewage sludge-treated soil: implications for the biodegradability of POPs

The impact of regular application of sewage sludge or farmyard manure on the organic contaminant loads in soil was assessed in a model rhizobox experiment. Two soils originating from a long-term field crop rotation and fertilizer experiment running since 1996 were used. The total polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), organochlorinated pesticides (OCPs), polybrominated diphenyl ethers (PBDEs), perfluorooctanoic acid (PFOA), and perfluorooctane sulfonate (PFOS) contents were determined in the rhizosphere and bulk soil. The results showed low but still detectable contents of PCBs and OCPs in the soil, substances which were banned a few decades ago. Among the OCPs, dichlorodiphenyltrichloroethane (DDT) and its metabolites reaching up to 18.2 µg kg^?1 of the soil even exceeded the preventive levels for these compounds in agricultural soils, i.e. 7.5 µg kg^?1 of soil. For PBDEs, PFOA, and PFOS, their contents in the soil significantly increased with sewage sludge application. The enhancement of the potential biodegradability of the POPs in the rhizosphere was confirmed only for hexachlorocyclohexane (γ-HCH), where, the level of γ-HCH increased significantly in the rhizosphere soil compared to bulk soil. Thus, natural attenuation of POPs in the soil-plant system seems to be insufficient for most of the investigated compounds.     

天津大沽排水河沉积物典型持久性有机污染物的分布特征与来源解析

分别使用气相色谱质谱仪和气相色谱仪对2010年5月采集的天津市大沽排水河8个沉积物样的16种多环芳烃（PAHs）和7种有机氯农药（OCPs）进行了调查,结果表明,沉积物中PAHs的总含量范围为370～5607ng·g-1,平均浓度为2041ng·g-1,OCPs的总含量范围为42.2～680ng·g-1,平均浓度为222ng·g-1。对其组成特征及来源进行了分析,结果表明,沉积物中PAHs主要以3～4环为主,5～6环较少,沉积物中PAHs主要来自化石燃料的燃烧或交通源贡献,以及少量石油产品的输入。滴滴涕（DDT）及其代谢产物的含量明显低于林丹类物质（HCHs）,HCHs有新的输入,DDT没有新的输入,其降解方式主要是厌氧降解。     

DDT and HCH Residues in Basmati Rice (Oryza sativa) Cultivated in Dehradun (India)

Organochlorine pesticides were used earlier for agricultureproduction. Their residues may still be present in soil and mayaccumulate in food crops, posing potential health problems to consumers. DDT, HCH, their isomers and metabolites were analyzedin samples of soil and rice plants collected from ten differentvillages of a well-known Basmati rice growing area in Dehradun.Residues of both pesticides were found in all samples ofsoil and different parts of rice plants except for a few grainsamples. Maximum residue was observed in husk and minimum ingrains. The average concentration of DDT in soil ranged from0.013 to 0.238 ppm. p,p′-DDE was the major metabolite (>63%). Theaverage concentration of DDT in rice grain varied from 0.002 to 0.040 ppm. o,p′-DDT was the main isomer (>93%). Theaverage concentration of HCH in soil ranged from 0.122 to 0.638 ppm. β-HCH was the predominant (43%) isomerfollowed by α-HCH (21%). The average HCH concentrationin rice grain ranged between 0.013 and 0.113 ppm. All four isomers were present in grains. The levels of DDT and CHCin grains were similar in magnitude as those from differentIndian states, but well below the maximum residue limit of 0.1 ppm for DDT and 0.05 ppm for HCH prescribed by the Government ofIndia and WHO/FAO. As such, the pesticide residue levels in thisexport commodity are not of hazardous nature.     

作物根系对土壤中老化HCH-DDT的富集作用

在室温条件下,采用盆栽试验方法研究了小麦和玉米作物根系对自然污染土壤中不同水平老化HCH、DDT的富集作用及其影响机制。通过连续提取,将根系富集的有机氯农药分为弱吸着、强吸着和吸收3种不同形态。结果表明,作物对老化HCH、DDT的富集存在选择性。在60d的试验周期内,玉米根系富集的HCH、DDT中55．4％～62．2％为根表强吸着,23．3％～36．9％为根内吸收;而小麦根系中HCH,DDT的73．8％-76．9％被根表强吸着,仅15．4％-20．5％可以进入根系组织内部。不同形态组分中异构体及代谢物的组成比例差异化明显,其中吸收态以β-HCH为主,强吸着态以P,p＇-DDT、p,p＇-DDE和P,p＇-DDD为主。随着土壤污染水平的增加,小麦和玉米根系对HCH、DDT的富集总浓度增加,而生物蓄积系数逆浓度梯度增加,小麦根系的富集能力强于玉米。在控制污染水平的条件下,作物根系对土壤老化HCH、DDT的富集量与其根系比表面积大小和总脂含量极显著正相关,而向根系深层组织运移的过程主要受总脂含量控制。     

天津郊区土壤与作物中有机氯农药残留现状与来源初析

通过在天津塘沽和宁河地区野外实地采样分析,了解研究区域有机氯农药各异构体在土壤及作物各部位的残留水平,并通过特征比值推测其来源。结果表明,塘沽和宁河地区土壤中六六六的残留浓度均值分别为88.76μg·kg^-1与98.46μg·kg^-1,β-HCH占绝对优势而γ-HCH均未在土壤样品中检出,α-HCH手性分析结果显示为非消旋体,均表明土壤中六六六来自历史残留而非新近输入或林丹的使用。塘沽和宁河地区滴滴涕的残留浓度均值分别为30.87μg·kg^-1与1.30μg·kg^-1,亦来自历史残留,在个别点位可能曾使用过三氯杀螨醇。作物样品中六六六与滴滴涕的含量较高,经对数变换的生物富集系数变化范围分别为0.24～0.73与2.02～2.90。六氯苯、七氯、艾氏剂、异艾氏剂、反式氯丹、顺式氯丹、狄氏剂与异狄氏剂在大部分土壤与作物样品中也有不同程度的检出。     

茶园土壤中有机氯杀虫剂的残留状况研究

2004年5月和6月采集了安徽、江苏、湖南、湖北省5个茶园的38个土壤表层样品,利用ASE萃取技术,使用GC/MS方法测定了样品中的六氯苯、氯丹、总滴滴涕(DDE、DDD和DDT)、艾氏剂、狄氏剂、异狄氏剂、七氯和灭蚁灵等八种有机氯杀虫剂。5个茶园的六氯苯、总滴滴涕的检出率都为97.4%,是茶园土壤中普遍存在的两类持久性有机污染物(POPs)。艾氏剂、狄氏剂、异狄氏剂、七氯等未检出。总有机氯杀虫剂含量平均为17.4!g kg-1,总滴滴涕占总有机氯杀虫剂含量的97.9%,是茶园土壤中有机氯杀虫剂残留的主要成分。六氯苯的残留量很低,没有对茶园土壤质量造成危害。     

海南省瓜菜田土壤中有机氯农药残留及生态风险分析

采用气相色谱法检测了海南瓜菜田的33个表层土壤样品中18种有机氯(OCPs)农药残留,并对其进行污染来源分析和初步生态风险评价。结果表明:(1)土壤中的OCPs检出率为90.9%,最高残留量为17.37 ng·g-1,平均值为2.30 ng·g-1;(2)18种OCPs均有检出,六六六(HCHs)、滴滴涕(DDTs)、硫丹类农药的检出率较高,分别为63.6%、57.6%、54.5%;(3)DDTs是主要残留物质,占总OCPs残留量的54.6%,18.2%的土样可能有DDTs新的输入,土壤中HCHs主要来源于过去使用的林丹;(4)与国内其他地区土壤和国家《土壤环境质量标准》(GB 15618—1995)一级标准相比,海南省瓜菜田土壤DDTs和HCHs残留量处于较低水平,生态风险也较低。     

静电场处理对贮藏番茄品质及生理变化的影响

为探讨静电场对番茄贮藏品质的影响,以“朝研219”绿熟番茄为试材,从控制软化和转红出发,筛选了适宜的静电场处理条件为：场强-200 kV/m,频度2 h/d。研究静电场处理对贮藏番茄品质和生理变化的影响,结果表明：静电场处理能显著延缓番茄果实硬度的下降,抑制由绿转红的过程;可以延缓果实可溶性糖含量的下降和可滴定酸含量的上升;经负高压静电场处理的番茄,呼吸跃变推迟6 d出现,乙烯峰的出现也延迟了3 d,相对电导率与丙二醛含量较对照明显降低,说明静电场处理可调控果实细胞膜透性的变化。     

污染土壤中六六六和DDT在温室中的分布特征及动态变化研究

应用PUF材料空气被动采样技术,研究了密闭温室条件下污染土壤中有机氯农药[DDT和六六六（HCH）]含量的动态变化及其向空气中扩散的规律。结果表明：土壤中∑HCHs和∑DDTs总量随着培养时间的延长而降低;空气中HCH和DDT浓度在20d时达到峰值,20d以后浓度逐渐降低。培养60d后,土壤中∑HCHs的浓度随土层深度增加而增加,0~2cm土层中∑HCHs的浓度（9.4±0.69）mg·kg-1显著低于6~8cm土层中的浓度（12.11±0.83）mg·kg-1;∑DDTs在土壤中浓度随土壤层次呈现先升高后降低的变化趋势。在温室条件下有机氯农药的异构体和降解产物的组成也发生一定变化,土壤中HCHs和DDTs在一定程度上被激活,温室条件也可能促进HCHs和DDTs的土-气交换过程;温室环境促进了p,p′-DDT和o,p′-DDT向p,p′-DDD和p,p′-DDE转化,从而增大DDT和HCH的环境风险。     

汕头地区农业生态系统中有机氯农药的研究

有机氯农药(Organochlorine Pesticides,OCPs)是一类由人工合成的杀虫广谱、毒性较低、残效期长的化学杀虫剂。本文以汕头市为研究区域,探讨了土壤OCPs的残留现状和特征,并对该区的土壤进行了环境质量评价和初步的生态风险评价。结果表明:(1)汕头地区土壤中OCPs的检出率高达99.13%,OCPs残留量的平均值是113.37ng·g-1,主要的OCPs污染物为DDTs和硫丹类;南澳县OCPs残留量平均值最高(174.68 ng·g-1),其次为龙湖区,濠江区含量平均值最低(69.24 ng·g-1);(2)与国内外一些地区土壤中OCPs的残留量对比,本研究区域土壤中的OCPs处于中等污染残留水平;与美国马里兰州标准、纽约州可容许的土壤浓度标准和我国的土壤环境质量标准相比较,OCPs基本没有超标;(3)本研究地区土壤存在较高的生态风险,OCPs可能对环境造成一定的危害,其中生态风险最高的是DDTs,BHCs的生态风险较低。     

Persistent organic pollutants in the natural environments of the city of Bratsk (Irkutsk Oblast): Levels and risk assessment

The contents of persistent organic pollutants (POPs)—polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs)—in the natural environments of an industrial city (Bratsk) of Irkutsk oblast have been studied. Features of the spatial and seasonal distribution of the PCBs and OCPs in the soils and the atmospheric air have been revealed. The structure of the homological and congeneric composition of the PCBs in the soils and the atmospheric air has been shown. Parameters of the carcinogenic and noncarcinogenic risks for human health from the impact of the PCBs and OCPs present in the soils and the atmospheric air have been determined.