Pesticides in groundwater: some observations on temporal and spatial trends

Following a monitoring programme of private shallow boreholes a total of 22 different pesticides were detected in 14 shallow boreholes in the Triassic Sherwood Sandstone aquifer of south Yorkshire, UK between January 2002 and November 2003. Of the 294 positive detections made, 34% were detected in excess of the permitted concentration value (PCV) (drinking water standard) for individual pesticides. Pesticides were detected in 11 (78%) of the boreholes, and in eight (57%) at concentrations exceeding the PCV on at least one occasion. These findings were complemented by data from deeper boreholes in which concentrations exceeding the PCV were also detected. Pesticide occurrence could be related to landuse; mecoprop and isoproturon were frequently detected at several locations reflecting the arable landuse, dicamba at a golf course, and atrazine, propazine and terbutryn near a railway. Temporal variations have emerged at individual sites and across the study area as the result of extended and frequent monitoring.     

异丙隆及其间位异构体、邻位异构体分析方法研究

采用高效液相色谱和气相色谱相结合,对异丙隆及其间位异构体、邻位异构体进行分离和测定。试验结果表明:异丙隆线性相关系数为0.996 1,相对标准偏差为0.19%,平均回收率为100.11%;间位异构体线性相关系数为0.995 9,相对标准偏差为2.26%,平均回收率为97.05%;邻位异构体线性相关系数为0.992 5,相对标准偏差为5.02%,平均回收率为97.61%。     

Preliminary studies in removing atrazine,isoproturon and imidacloprid from water by natural sepiolite

Sepiolite is a hydrated magnesium silicate clay with a fibrous structure and binder properties. To calculate the potential use of sepiolite in removing atrazine [2‐chloro‐4‐ethylamino‐6‐isopropilamino‐1,3,5,‐triazine], isoproturon [3‐(4‐isopropylphenyl)‐1,1‐dimethylurea] and imidacloprid [1‐(6‐chloro‐3‐pyridinylmethyl)‐N‐nitroimidazolin‐2‐ylideneamine] from water, the adsorption of atrazine, isoproturon and imidacloprid on sepiolite desiccated at 110 °C from aqueous solution at 25 °C has been studied by using batch experiments. In addition, column experiments were carried out with the sepiolite sample using aqueous solutions of atrazine, isoproturon and imidacloprid at a concentration of 20.0 × 10⁻⁴ cmol dm⁻³. The experimental data points have been fitted to the Langmuir equation to calculate the adsorption capacities (X_m). Values for X_m ranged from 2.70 × 10⁻¹ cmol kg⁻¹ for isoproturon up to 3.97 × 10⁻¹ cmol kg⁻¹ for atrazine. The removal efficiency (R) ranged from 36.7% for isoproturon up to 74.3% for atrazine. The batch experiments show that the sepiolite is more effective in adsorbing atrazine than imidacloprid and isoproturon. The column experiments show that sepiolite might be reasonably used in removing atrazine, the column efficiency being 46%. The data indicate that a readily available and inexpensive Spanish sepiolite can be employed as a filter for contaminated waters with these pesticides, controlling their release to the environment. © 1999 Society of Chemical Industry     

非异氰酸酯法合成除草剂异丙隆

报道了以氯甲酸甲酯为起始原料合成除草剂异丙隆的方法。考察了原料配比,反应温度和反应时间对反应的影响。结果表明,氯甲酸甲酯法制除草剂异丙隆,总收率为82.7%,原药纯度达95%。     

HPLC法分析40%氟噻草胺·吡氟酰草胺·异丙隆悬浮剂含量

[目的]采用HPLC建立检测40%氟噻草胺·吡氟酰草胺·异丙隆悬浮剂含量的方法。[方法]采用高效液相色谱法,以0.1%磷酸水溶液-乙腈为流动相梯度洗脱,使用Extend C18柱和DAD检测器,对试样中的氟噻草胺、吡氟酰草胺和异丙隆进行测定,外标法定量。[结果]该分析方法氟噻草胺、吡氟酰草胺和异丙隆线性相关系数分别为0.9999、0.9999和0.9998,变异系数分别为0.73%、0.84%和0.57%,平均回收率分别为101.09%、100.91%和101.12%。[结论]该方法的操作简单,精密度、准确度和灵敏度均满足要求,可用于40%氟噻草胺·吡氟酰草胺·异丙隆悬浮剂含量检测。     

非异氰酸酯法合成除草剂异丙隆

报道了以氯甲酸甲酯为起始原料合成除草剂异丙隆的方法。原料对异丙基苯胺先与氯甲酸甲酯反应生成对异丙基苯胺甲酸甲酯,再与二甲胺反应生成异丙隆。避免了异氰酸酯路线的种种缺点,具有收率高、含量高、成本低的特点。考察了原料配比,反应温度和反应时间对反应的影响。结果表明,在适合条件下,氯甲酸甲酯法可制得除草剂异丙隆,总收率为82.7%,原药纯度达95%。     

异丙隆半抗原的制备及鉴定

为了建立除草剂异丙隆的酶联免疫吸附测定(ELISA)方法,以对异丙基苯基异氰酸酯和N甲基已内酰胺为原料,经N甲基已内酰胺水解,而后与对异丙基苯基异氰酸酯反应,合成了与目标分子具有相似结构的异丙隆半抗原1(5戊基羧基)3(4异丙基苯基)1甲基脲。产物结构以红外及核磁等分析方法确认。为进一步研制异丙隆免疫抗体的制备奠定了基础。     

异丙隆防除麦田杂草效果及施用技术研究

25%异丙隆WP对麦田牛繁缕、看麦娘、菵草的防效均在85%以上,而6.9%骠马胶悬剂对牛繁缕的防效仅为20.66%,85%甲磺隆钠盐对菵草的防效为26.39%。施用异丙隆900ga.i./hm^2时,25%异丙隆WP对麦田杂草的综合防效为85.29%;50%异丙隆WP和75%异丙隆WP对麦田杂草的综合防效分别为92.1%和95.8%,在相同剂量下,药效差异不显著,但显著高于25%异丙隆WP的药效;采用扇型喷头与细孔喷头喷施异丙隆防除麦田杂草的效果一致,而扇型比细孔喷头可节时7.33-11.73h/hm^2。     

快灭灵与异丙隆混用防除麦田杂草

快灭灵与异丙隆混用防除麦田杂草试验表明：用40%快灭灵3～4g 50%异丙隆125g/667m^2可有效防除多种杂草,药后140d,对禾本科杂草的防效为82.9%～87.7%,对阔叶杂草的防效为68.6%～81.0%,总株防效为77.1%～84.9%,总鲜重防效为87.6%～92.4%。本试验条件下使用,对小麦安全。     

Determination of the herbicide isoproturon in cereal grains and pasta by LC with LC/MS confirmation

A method was developed for the determination of the herbicide isoproturon in wheat, maize, oats and pasta, with a limit of determination of 0.05 mg kg^-1. Isoproturon was extracted from moistened samples using a mixture of acetone, hexane and dichloromethane. The resulting extract was cleaned-up by solid-phase extraction using aminopropyl-bonded silica cartridges and analysed by reversed-phase liquid chromatography with photodiode array detection. Confirmation was by electrospray liquid chromatography-mass spectrometry. Recoveries from seven samples of each of the four matrices spiked with isoproturon at 0.05 and 0.5 mg kg^-1 were in the range 88-104%. The method was used to monitor cereal grains and pasta as part of the UK food monitoring programme.