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1.
[14C]Endrin was fed to two lactating cows in a portion of their diet for 21 days. The intake was equivalent to approximately 0.1 mg of endrin per kg of total diet. Excretion of radioactivity in milk, urine and faeces reached equilibrium with intake between 4 and 9 days after starting treatment. Milk residues reached 0.003–0.006 mg/kg, were composed of unchanged endrin and were located in the fat. Muscle residues reached 0.001–0.002 mg/kg. Residues in the fat reached a maximum of 0.1 mg/kg and were due to unchanged endrin. [14C]Endrin was administered in corn oil to six laying hens for 21 weeks. The intake was equivalent to approximately 0.13 mg/kg of total diet. Ingestion and excretion were almost in balance at 16–20 weeks. Egg residues reached 0.11–0.18 mg/kg, were composed of unchanged endrin and were located in the yolk. Tissue residues were 0.01 mg/kg in breast, 0.1 mg/kg in leg, 0.17 mg/kg in kidney, 0.47 mg/kg in liver and 1.0 mg/kg in fat. The residues were accounted for as unchanged endrin except in liver and kidney in which part was probably due to polar metabolites in the process of excretion. The results show that endrin is much more rapidly metabolised in cows than in hens. The pathways of metabolism were fundamentally the same in both species, the major product being anti-12-hydroxyendrin, which was found un-conjugated in cow urine and faeces and as the O-sulphate conjugate in hen excreta. The only observed difference in primary metabolism was some syfl-12-hydroxyendrin and 12-ketoendrin in cows. This pathway was not detected in hens.  相似文献   

2.
A method is described for the estimation of residues of the carbamate insecticide promacyl [5-methyl-m-cumenyl butyryl(methyl)carbamate] and its metabolites that are hydrolysable to isothymol (m-cymen-5-ol), using high-performance liquid chromatography with electrochemical detection to determine the isothymol. Clean-up of samples relied on the steam volatility of phenols. Recoveries at the 0.1 mg kg?1 level varied from 72–88% for fat tissue and 81–91% for liver. The limits of detection were found to be 0.01 mg kg?1 for and 0.02 mg kg?1 for liver. A comparative study of the chromatography of sample extracts using both ultraviolet detection and electrochemical detection showed a substantial decrease in the level of interfering co-eluates in the latter method. A field trial, involving a single spray application of the formulated acaricide on milking cattle, revealed residues in the butter fat comparable with those found in a previous investigation.  相似文献   

3.
采用高效液相色谱-串联质谱 (HPLC-MS/MS) 检测技术,建立了吡唑醚菌酯及其代谢物 BF-500-3 在龙眼中残留分析方法,并依据“农作物中农药残留试验准则”,开展了30%吡唑醚菌酯悬浮剂 (SC) 在广东省广州市和云南省玉溪市两地龙眼上的田间残留试验,研究了吡唑醚菌酯及其代谢物 BF-500-3 在龙眼中的降解和转化规律。样品采用乙腈提取,经PSA和C18吸附剂净化,HPLC-MS/MS检测分析。结果表明:在0.001、0.1及2 mg/kg添加水平下,吡唑醚菌酯和 BF-500-3 在龙眼中的平均回收率为84%~96%,相对标准偏差 (RSD) 为3.8%~6.7%,检出限 (LOD) 为0.25 × 10?3 mg/kg,定量限 (LOQ) 为0.001 mg/kg。田间试验结果显示:采用30%吡唑醚菌酯SC于龙眼初果期开始施药,施药剂量为有效成分375 mg/kg,施药3~4次,施药间隔7~10 d条件下,距末次施药后5、7、10 d分别取样测定,龙眼中吡唑醚菌酯及其代谢物 BF-500-3 的残留量分别为0.11~0.72和0.011~0.071 mg/kg。研究结果可为指导吡唑醚菌酯在田间的科学合理使用及制定其在龙眼上的最大残留限量 (MRL) 提供参考。  相似文献   

4.
Sheep were dosed orally with diazinon at 450 and 600 mg/kg: residues of diazinon were determined in the blood, brain, liver, kidney cortex and medulla, muscle, fat and rumen contents at intervals after dosing, and cholinesterase activities in the erythrocytes and the brain were determined at the same intervals. The relations between residues, cholinesterase activity and clinical symptoms are discussed from the points of view of their diagnostic value and the possibility of undesirable residues occurring in poisoned animals. Rough estimates of the residues of two metabolites, hydroxydiazinon and dehydro-diazinon, in one sheep are also discussed. The oxygen analogue of diazinon was not detected although it was specifically sought.  相似文献   

5.
Blackcurrants, treated with 0.1 kg of 2,4,5-T ha?1 (as esters of mixed C4–C6 alcohols; ‘Tormona 80’), contained 0.1 mg of 2,4,5-T residues kg?1 in the berries at ripeness 29 days after treatment. Total residues in the berries were not reduced during growth and ripening, although the residue concentrations declined in the same period due to growth dilution. In spinach leaves from old plants, treated with 0.1 kg ha?1, 0.05 mg of 2,4,5-T kg?1 was found 14 days after treatment. Fodder peas showed no residues (< 0.002 mg kg?1) at harvest 62 days after treatment with 2,4,5-T esters. After application of 0.1 kg ha?1 on potato plants, the disappearance of 2,4,5-T was rapid during the first month, but residues were translocated into the tubers and reached a constant level of 0.02 mg kg?1 after 1 month until harvest at 108 days after treatment. In all crops, visible effects were observed after treatment with 0.1 kg ha?1. After the application at 0.01 kg ha?1, phytotoxic effects were observed only in blackcurrants, but negligible residues were found in all the test crops.  相似文献   

6.
The depletion of zeta‐cypermethrin residues in bovine tissues and milk was studied. Beef cattle were treated three times at 3‐week intervals with 1 ml 10 kg?1 body weight of a 25 g litre?1 or 50 g litre?1 pour‐on formulation (2.5 and 5.0 mg zeta‐cypermethrin kg?1 body weight) or 100 mg kg?1 spray to simulate a likely worst‐case treatment regime. Friesian and Jersey dairy cows were treated once with 2.5 mg zeta‐cypermethrin kg?1 in a pour‐on formulation. Muscle, liver and kidney residue concentrations were generally less than the limit of detection (LOD = 0.01 mg kg?1). Residues in renal‐fat and back‐fat samples from animals treated with 2.5 mg kg?1 all exceeded the limit of quantitation (LOQ = 0.05 mg kg?1), peaking at 10 days after treatment. Only two of five kidney fat samples were above the LOQ after 34 days, but none of the back‐fat samples exceeded the LOQ at 28 days after treatment. Following spray treatments, fat residues were detectable in some animals but were below the LOQ at all sampling intervals. Zeta‐cypermethrin was quantifiable (LOQ = 0.01 mg kg?1) in only one whole‐milk sample from the Friesian cows (0.015 mg kg?1, 2 days after treatment). In whole milk from Jersey cows, the mean concentration of zeta‐cypermethrin peaked 1 day after treatment, at 0.015 mg kg?1, and the highest individual sample concentration was 0.025 mg kg?1 at 3 days after treatment. Residues in milk were not quantifiable beginning 4 days after treatment. The mean concentrations of zeta‐cypermethrin in milk fat from Friesian and Jersey cows peaked two days after treatment at 0.197 mg kg?1 and 0.377 mg kg?1, respectively, and the highest individual sample concentrations were 2 days after treatment at 0.47 mg kg?1 and 0.98 mg kg?1, respectively. © 2001 Society of Chemical Industry  相似文献   

7.
Marked seasonal changes in the BHC content of butter in Northern Ireland are reported. Levels of alpha-BHC rise to a maximum of between 0.5 and 0.9 mg/kg on a fat basis in January and February, falling to between 0.02 and 0.04 mg/kg in late summer and early autumn. The use of veterinary preparations containing technical BHC for the control of lice infection in the winter months would appear to be responsible for such fluctuations. Maximum BHC contamination of milk in January and February probably arises by direct ingestion or skin absorption of externally applied BHC and subsequent transfer from the bloodstream to the milk fat. A later smaller contamination peak in the April/May period is probably due to mobilisation of BHC stored in the body fat of the animals during the first weeks after parturition.  相似文献   

8.
四聚乙醛在烟草和土壤中的残留检测与消解动态   总被引:4,自引:0,他引:4  
建立了烟草和土壤中四聚乙醛残留量的气相色谱分析方法。样品中残留的四聚乙醛用二氯甲烷提取,中性氧化铝与活性炭混合柱净化,偏重亚硫酸钠溶液除去游离醛,所得的四聚乙醛经盐酸解聚成乙醛,乙醛与2,4-二硝基苯肼进行衍生化反应,经硅胶柱净化,GC-NPD测定其衍生物。方法的最小检出量为0.04 ng,最低检出浓度为0.02~0.10 mg/kg;3个添加水平的平均回收率为86%~100%,相对标准偏差(RSD)均小于15%(n=5)。四聚乙醛在烟草及土壤中的残留试验结果表明:烟草植株对四聚乙醛的吸收在施药后4~5 d达到高峰,之后缓慢下降,到21 d已接近最低检出浓度0.04 mg/kg;其在土壤中的半衰期约为4 d;在推荐使用剂量下,四聚乙醛在干烟叶中的残留量低于最低检出浓度0.10 mg/kg,不会对烟草造成残留污染。  相似文献   

9.
多菌灵在杭白菊及其土壤中的残留消解动态   总被引:2,自引:1,他引:1  
通过田间植株直接施药-定期采样提取-高效液相色谱分析的方法,研究了多菌灵在杭白菊胎菊、菊花及土壤中的残留消解动态,测定了多菌灵在杭白菊胎菊和菊花中的最终残留量,并在室内探讨了不同温度对干胎菊和干菊花中多菌灵消解的影响。结果表明:在0.675和1.00 kg/hm2 2个施药剂量下,多菌灵在杭白菊土壤、胎菊和菊花中的消解半衰期分别为7.98~8.34 d、3.90~4.05 d和3.31~3.45 d;不同温度下,干胎菊和干菊花中多菌灵的半衰期存在显著性差异(P2的剂量喷雾施用2次,第2次施药后21 d时多菌灵在干胎菊和干菊花中的残留量分别为0.182~0.294 mg/kg和0.371~0.381 mg/kg,远低于我国制定的多菌灵在怀菊中的最大残留限量标准(5 mg/kg)。  相似文献   

10.
为明确氟唑菌酰胺和吡唑醚菌酯在芒果上的残留行为,于2012和2013年在中国广东省和广西自治区进行了氟唑菌酰胺和吡唑醚菌酯在芒果上的田间残留及消解动态试验,建立了芒果中氟唑菌酰胺及吡唑醚菌酯残留量的高效液相色谱检测方法。样品用丙酮提取,乙酸乙酯液-液分配萃取,弗罗里硅土柱层析净化,高效液相色谱-二级管阵列紫外检测器检测,外标法定量。结果表明:氟唑菌酰胺和吡唑醚菌酯在芒果上的消解半衰期分别为7.2~9.1和8.0~11.0 d;采用42.4%吡唑醚菌酯·氟唑菌酯胺悬浮剂(SC),分别按有效成分200和300 mg/L的剂量于幼果期开始施药,施药3~4次,施药间隔期为10~15 d,距最后一次施药后7和14 d采样测定,芒果中氟唑菌酰胺和吡唑醚菌酯的残留量分别为0.004~0.053和0.004~0.072 mg/kg。其中,吡唑醚菌酯残留量符合中国制定的最大残留限量(MRL)标准(0.05 mg/kg),根据试验结果,建议中国可将氟唑菌酰胺在芒果上的MRL值暂定为0.2 mg/kg。  相似文献   

11.
In order to assess some of the residue characteristics of the experimental carbamate acaricide, 3-methyl-5-isopropylphenyl-N-(n-butanoyl-)-N-methylcarbamate (promacyl) a 0.2 % aqueous emulsion was applied to cattle in a series of five trials and in a sixth, the technical product was added to the feed of stalled cattle. A method of analysis involving the formation of a derivative suitable for gas chromatographic analysis on electron capture detection mode was developed. Separate estimations of levels of the parent compound and the metabolites, 3-methyl-5-isopropylphenyl -N-methylcarbamate and 3-methyl-5- isopropylphenol, were carried out on fatty tissues and butterfat but for non-fatty tissues “total” levels, which were a combined estimate of 3-methyl-5-isopropylphenol itself and all substances hydrolysable to it, were estimated and quoted as Promacyl. The highest group average level of the parent compound was 0.9 part/million in fatty tissues 24 h after the last of 8 applications at 3 day intervals. In a single spray trial the maximum group average of 0.7 part/million in fatty tissues 24 h after treatment fell to 0.2 part/million after 5 days. Residues in butterfat, 7 h after a single dermal application showed a maximum level of 1.2 parts/million and this declined to 0.1 part/million on the seventh day after treatment. “Total” residues in non-fatty tissues were of the order of 1/10 those found in fatty tissues.  相似文献   

12.
毒死蜱在杨梅果实中的残留及消解动态   总被引:1,自引:0,他引:1  
为探明毒死蜱在杨梅果实中的残留消解动态和最终残留量,于2013-2015年在浙江省临海市进行了毒死蜱在杨梅果实中的残留消解动态和最终残留量试验。结果表明:于杨梅春梢(幼果)生长期,在树冠均匀喷施48%毒死蜱乳油800倍液1次的施药条件下,毒死蜱在‘东魁’和‘临海早大梅’2个品种果实中的消解动态基本一致,均符合一级动力学方程,半衰期为4.60~5.78 d,降解速度较快。综合3年试验结果,施药后23 d,毒死蜱在杨梅果实中的残留量为0.26~0.45 mg/kg,低于中国(苹果、梨、荔枝和龙眼)及日本(其他浆果)最大残留限量标准(MRL,1 mg/kg);施药后34 d,毒死蜱在杨梅果实中的残留量为0.074~0.28 mg/kg,低于香港草莓中MRL值(0.3 mg/kg);但施药后44 d,毒死蜱在果实中的残留量为0.073~0.13 mg/kg,仍高于欧盟蓝莓及桑椹中毒死蜱的MRL值(0.05 mg/kg)。膳食风险评估结果表明,施药后23、27、34和44 d采收的杨梅果实中毒死蜱对2~6岁、7~14岁、18~30岁和60~70岁4类人群的膳食摄入风险商值及急性膳食风险均较低,处于安全水平。  相似文献   

13.
建立了对氯苯氧乙酸钠在荔枝和土壤中的残留分析方法,并在广州和南宁进行了8%对氯苯氧乙酸钠可溶性粉剂在荔枝上残留的田间试验,研究了对氯苯氧乙酸钠在荔枝和土壤中的消解动态和最终残留量。样品用碱溶液提取,盐酸调节pH值至2.5后乙酸乙酯萃取,采用高效液相色谱二极管阵列紫外检测器(HPLC-PDA)检测。结果表明:在0.01、0.1和1 mg/kg 3个添加水平下,对氯苯氧乙酸钠在荔枝和土壤中的平均回收率为81%~85%,相对标准偏差(RSD)为1.9%~4.6%,检出限(LOD)为0.005 mg/kg,定量限(LOQ)为0.01 mg/kg。田间试验结果表明:8%对氯苯氧乙酸钠可溶性粉剂在荔枝和土壤中的半衰期分别为3.2~5.9 d和15.2~20.6 d,属易降解农药。最终残留量测定结果显示:8%对氯苯氧乙酸钠可溶性粉剂按有效成分20和30 mg/L分别施药2次,广州和南宁两地收获期荔枝中对氯苯氧乙酸钠的残留量均<0.01 mg/kg。  相似文献   

14.
In a dietary toxicity study, laying hens received a diet containing the rodenticide flocoumafen at concentrations of 1.5, 5, 10 and 50 mg kg?1 for five consecutive days. The LC50 at termination following a 28-day observation period was 16.4 mg kg?1. Livers of birds which received doses of flocoumafen between 5 and 50 mg kg?1 had concentrations of flocoumafen (1.5 nmol g?1) that were independent of dose. The data indicate the presence in hen liver of a saturable high-affinity flocoumafen binding site with similar characteristics and capacity to that of the quail and rat. Residues of flocoumafen in samples of breast and leg muscle were low in all exposure groups. Higher, dose-related residues were found in samples of abdominal fat and skin-associated fat and there was a clear demonstration of the transfer of dose-related residues into eggs. In a separate study in which hens were dosed with [14C]flocoumafen for five consecutive days at a daily rate of 1 and 4 mg kg?1 body weight, the majority (68 %) of the daily radioactive dose was eliminated over the following 24 hours via excreta. Residues in liver at death or when killed accounted for < 1 % of the cumulative administered radioactivity. Residues in eggs were located primarily in the yolk with maximum concentrations 1.0 mg kg?1 or 0.18% of the low dose; 2.1 mg kg?1 or 0.06% of the high dose as [14C]flocoumafen equivalents were observed at 10 days after start of dosing. Some 40 % of the total activity in the yolk was unchanged flocoumafen.  相似文献   

15.
采用乙腈提取、固相萃取法净化和高效液相色谱(HPLC-UV)检测方法,研究了乙嘧酚在苹果中的消解动态及最终残留。结果表明:采用70%甲基硫菌灵(50%)·乙嘧酚(20%)可湿性粉剂,在乙嘧酚有效成分为525 mg/kg剂量下对苹果植株喷雾施药,2010和2011年乙嘧酚在苹果中的半衰期(t1/2)分别为1.94~2.65 d和2.07~2.70 d;在525 mg/kg剂量下施药4次,间隔期10 d,距第4次施药后7 d时,乙嘧酚在苹果中的最终残留量低于最低检测浓度(0.02 mg/kg),远低于欧盟规定的最大残留限量值(0.1 mg/kg)。  相似文献   

16.
采用气相色谱-微池电子俘获检测器(GC-μECD)测定了900 g/L异丙草胺乳油在土壤、玉米植株和玉米籽粒中的消解动态和最终残留。土壤、玉米植株和籽粒样品用石油醚-丙酮(1∶1,体积比)提取,经液液萃取,弗罗里硅土柱净化,GC-μECD检测,外标法定量。结果表明:异丙草胺在各供试样品中的添加水平为0.011~1.1 mg/kg时,回收率在78.8%~96.4%之间,相对标准偏差(RSD)为0.54%~10.5%;在土壤、玉米植株和籽粒中的定量限(LOQ)均为0.011 mg/kg。异丙草胺在土壤和玉米植株中的半衰期,2009年分别为4.7~5.3 d和4.1~4.5 d,2010年分别为5.4~5.5 d和4.9~5.4 d。按推荐高剂量(有效成分)2 400 g/hm2及其1.5倍剂量(3 600 g/hm2)施药,于玉米苗后茎叶初期施药1次,在玉米乳熟期和成熟期时,玉米籽粒中异丙草胺的最终残留量均低于定量限。玉米收获时(距施药45 d),土壤和玉米中的异丙草胺残留量均低于参考的MRL值(0.1 mg/kg),说明按规定在玉米田使用900 g/L的异丙草胺乳油是安全的。  相似文献   

17.
Fenvalerate, deltamethrin, (1R)-cis-permethrin, (1R)-trans-permethrin and (1S)-trans-permethrin, applied topically to the entire body surface of steers at a rate of 1 mg a.i. kg−1, provided 70% or better protection from black flies on cattle for 16, 9, 8, 6 and 6 days, respectively. The (1S)-cis stereoisomer of permethrin was ineffective as a protectant against black flies at a rate of 1 mg a.i. kg−1 when applied as a total body spray. One poly(vinyl chloride) ear tag containing 10% permethrin, in each ear of steers, provided protection from black fly attack for up to 13 days under field conditions. Poly(vinyl chloride) ear tags containing 8% fenvalerate, installed in each ear of steers, did not provide satisfactory protection from black flies under field conditions.  相似文献   

18.
为明确不同生育期豇豆上施用乐果可能产生的残留风险,以40%乐果乳油按有效成分设低(540 g/hm2)、中(600 g/hm2)和高(900 g/hm2)3个施药剂量,开展了苗期、结荚期2次施药和结荚期3次施药3种场景下的田间模拟试验,按照一定的时间间隔采集成熟豇豆样品,采用乙腈提取,C18分散净化,超高效液相色谱-串联质谱检测。结果表明:乐果和氧乐果在豇豆中的定量限均为0.01 mg/kg,在0.01~2 mg/kg添加水平下,乐果和氧乐果的平均回收率在77%~101%,相对标准偏差为3.1%~17%。距苗期最后一次施药后10 d,乐果在豇豆中的残留量各处理均低于中国国家标准中规定的最大允许残留限量(MRL)值0.5 mg/kg,最高为0.043 mg/kg;但其代谢物氧乐果残留量在施药后14 d,仅540 g/hm2的处理低于其MRL值0.02 mg/kg,施药后18 d仍有检出,最高为0.013 mg/kg。于结荚期2次和3次施药条件下,豇豆中乐果的残留量分别于施药后3 d和5 d即低于其MRL值(0.5 mg/kg);而其代谢产生的氧乐果在施药后10 d仅540 g/hm2处理在豇豆中的残留量低于其MRL值。表明乐果使用后的残留超标风险主要源于其代谢物氧乐果。因此,建议豇豆结荚期不宜施用乐果,对其在苗期施用也应严格限制。  相似文献   

19.
建立了一种基于QuEChERS方法提取净化,超高效液相色谱/气相色谱-串联质谱检测桃叶、桃果和土壤中吡虫啉、嘧菌酯、腈苯唑、苯醚甲环唑、毒死蜱及β-氯氰菊酯6种农药残留量的分析方法。结果表明:在0.05~20 mg/kg (桃叶)、0.05~2 mg/kg (桃果) 和0.05~5 mg/kg (土壤) 添加水平下,6种农药在桃叶、桃果及土壤中的回收率为72%~111%,相对标准偏差 (RSDs) 为0.90%~18% (n = 5),均满足农药残留检测的要求。不套袋施药时,6种农药在桃叶中的原始沉积量最高,其沉积量占比为桃叶、桃果和土壤中总残留量的57%~69%;其次是土壤中,占比为25%~39%,桃果中占比仅为3%~6%;此外,2次施药后14和21 d时桃果上6种农药的最终残留量分别为 (0.07 ± 0.01)~(0.77 ± 0.13) mg/kg和 <0.05~(0.27 ± 0.05) mg/kg,分别为其对应最大残留限量(MRL)值的15%~60%和9%~34%。套袋可以显著降低桃果中6种农药的原始沉积量和最终残留量。套袋后,桃果上6种农药的原始沉积量占比均小于1%,且2次施药后14和21 d时的最终残留量均低于中国国家标准GB 2763—2019《食品安全国家标准 食品中农药最大残留限量》中对应MRL值的10%。本研究明确了果实套袋对6种农药在桃园中的沉积和残留的影响,为指导果实套袋措施在桃园中的安全使用提供了理论依据。  相似文献   

20.
3种新型杀虫剂对苹果黄蚜的毒力效果评价   总被引:1,自引:0,他引:1  
采用浸叶法在室内测定了3种药剂对苹果黄蚜的毒力,并在田间进行了防治试验。室内毒力测定结果表明:供试3种新型药剂中,双丙环虫酯和氟吡呋喃酮对苹果黄蚜的毒力较高,LC50分别为3.16 mg/L和23.58 mg/L,三氟苯嘧啶毒力较低,LC50为329.92 mg/L。田间试验结果表明:3种药剂对苹果黄蚜均有较好的速效性和持效性。17%氟吡呋喃酮可溶液剂和10%三氟苯嘧啶悬浮剂各处理3~7 d防效为82.19%~93.45%,药后30 d防效达到78.91%~87.92%;50 g/L双丙环虫酯可分散液剂2.5 mg/kg和4.2 mg/kg处理药后3~7 d防效为94.64%~97.04%,药后21 d防效仍可达88%以上。因此,3种新型药剂均可以用于防治苹果黄蚜,田间使用时推荐有效成分用量为双丙环虫酯2.5~4.2 mg/kg,氟吡呋喃酮113~170 mg/kg,三氟苯嘧啶28~80 mg/kg。  相似文献   

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