Removal of Carbaryl Pesticide from Aqueous Solution by Adsorption on Local Clay in Agadir

This study was conducted to assess the removal efficiency of pesticide (Carbaryl) used in Souss Massa region (Agadir city), on a clay originated from barrage situated in Agadir. The adsorption of Carbaryl from aqueous solution by local clay as a low-cost, natural and eco-friendly adsorbent was investigated. Different physicochemical parameters were analyzed: adsorbent mass, ionic strength (NaNO3), initial concentration of pollutant, temperature, and pH. The empirical results showed that all these parameters have an impact on the retention of pesticide on the clay. The equilibrium uptake was increased with an increase in the initial pesticide concentration in solution. The results of adsorption were fitted to the Langmuir and Freundlich isotherms. The Freundlich model represented the adsorption process better than Langmuir model, with correlation coefficients (R2) values ranged from 0.97 to 0.99. This study has shown that the natural clay is a solid that has got an important adsorption capacity, which may be used in treatment and depollution of water.

Impact of Nonlethal Levels of Metacid-50 and Carbaryl on Thyroid Function and Cholinergic System of Channa punctatus

With regard to brain acetylcholinesterase and acetylcholine and serum triiodothyronine(T_3) and thyroxine(T_4)profiles,a biphasic response pattern was elicited in Channa punctatus chroni- cally exposed to nonlethal doses of locally used pesticides,namely,Metacid-50 and Carbaryl. Data revealed that these xenobiotics caused significant inhibition of brain acetylcholinesterase activity and a decrease in thyroxine level accompanied by a concurrent increase in acetylcholine accumulation and T_3 level.It is surmised that Metacid-50 and Carbaryl influence both neural and hormonal functions.1989 Academic Press.Inc.

Sensitized effect of β-cyclodextrin on the fluorescence in the determination of carbaryl

Based on the significant enhancement of fluorescence intensity of carbaryl in inclusion complex, a spetrofluorimetric method with high sensitivity was developed for the determination of carbaryl in aqueous solution. Under the optimum conditions, the complex had excitation and emission maxima at 278 nm and 332 nm, respectively. The linear range of the method was 7.0 ng/ml—1500 ng/ml with a detection limit of 1.2 ng/ml. The proposed method was successfully used to determine quantitatively of carbaryl in cottonseeds.

Night-time Rise in Rat Pineal N-Acetyltransferase due to Carbaryl Administration Is Reduced by Propranolol Treatment

The purpose of the present study was to examine the effects of administration of sublethal doses of carbaryl on nighttime rat pineal melatonin synthesis in the presence and absence of propranolol, a β-adrenergic receptor antagonist. Two groups of adult male albino rats were administered orally N-methyl-l-naphthylcarbamate (carbaryl) (8. 33mg/kg BW daily in corn oil) for six successive days; another two groups received corn oil only.On the last day of carbaryl treatment, half of the animals received an intraperitoneal injection of propranolol (20 mg/kg body weight, one hour before lights off). The other two groups were given a saline injection. Four hours after darkness onset, pineal N-acetyltransferase (NAT) and hydroxyindole-O-methyltransferase (HIOMT) activities as well as pineal concentrations of 5-hydroxytryptophan (5HTP), serotonin (5HT),5-hydroxyindole acetic acid (5HIAA) and pineal and serum melatonin levels were measured. Nocturnal NAT activity was increased due to carbaryl administration but the pesticide was ineffective in stimulating NAT activity in rats treated with propranolol.Pineal 5HT was decreased due to carbaryl administration but 5HTP and 5HIAA levels were unaffected. Pineal and serum melatonin levels were decreased due to propranolol treatment. The results indicate that carbaryl may influence pineal NAT activity by a mechanism that involves β-adrenergic neural transmission.

Impairment of the Regulation of Gonadal Function in Channa punctatus by Metacid-50 and Carbaryl under Laboratory and Field Conditions

Regulation of gonadal function by gonadotropic hormone (GtH) and gonadotropin-releasing hormone (GnRH) in Channa punctatus was significantly affected by nonlethal levels of Metacid-50 and Carbaryl. Under laboratory conditions, the time-dependent decrease in serum GtH level was higher in Carbaryl-treated fish than in Metacid-50-treated fish. The situation was reversed in the field, with a higher inhibitory effect of Metacid-50 being recorded. On the other hand, pituitary GtH content and GnRH activity were inhibited to a greater extent by Metacid-50 than by Carbaryl under both field and laboratory conditions. The present findings highlight that even low doses of Metacid-50 and Carbaryl are effective enough to cause reproductive damage, as evidenced by homeostatic unbalance of the reproductive regulatory system. 1990 Academic Press. Inc.

Evaluation of Cytotoxicity and Genotoxicity of Insecticide Carbaryl to Flounder Gill Cells and Its Teratogenicity to Zebrafish Embryos

In this study, we determined the cytotoxicity and genotoxicity of carbamate insecticide carbaryl to flounder gill(FG) cells and its teratogenicity to zebrafish embryos. The cytotoxicity of carbaryl to FG cells was determined with methods including MTT and neutral red uptaking(NRU), lactate dehydrogenase(LDH) releasing and Hoechst 33342 and propidium idodide(PI) double staining. Moderate cytotoxicity in a concentration-dependent manner was observed. The 24 h-IC50 value of 53.48 ± 1.21, 59.13 ± 1.19 and 46.21 ± 1.24 mg L-1 carbaryl was obtained through MTT, NRU and LDH assays, respectively. Double fluorescence staining demonstrated that carbaryl induced the death of FG cells mainly through necrosis. There was no significant genotoxicity found in the FG cells exposed to the highest testing concentration of carbaryl(20 mg L-1, P > 0.05) as was demonstrated by Comet assay. Zebrafish embryos exposed to carbaryl at concentrations ≥10 mg L-1 displayed moderate toxic effects on the survival, spontaneous movement, hatching, heart rates of the embryos and their development, which were evidenced by yolk and pericardial sac edemas, body length reduction and tail flexure in time- and concentration-dependent manners at specific stages. The 24 h-, 48 h- and 96 h-LC50 values of carbaryl to zebrafish embryos were 41.80 ± 1.10, 17.80 ± 1.04 and 14.46 ± 1.05 mg L-1, respectively. These results suggested that carbaryl is moderately toxic to FG cells cultured in vitro and zebrafish embryos, and the FG cells were similar to zebrafish embryos in their sensitivity to carbaryl as 24 h-IC50 and LC50 indicated.

Synergistic effects of structural, crystalline, and chemical defects on the photocatalytic performance of Y-doped ZnO for carbaryl degradation

In this study,a photocatalytic material consisting of ZnO and yttrium-doped ZnO(YZO)nanoparticles was obtained via a facile precipitation conducted under ambient pressure whereby crystalline ZnO was successfully doped with yttrium.YZO had a hexagonal wurtzite polycrystalline structure with smaller crystal and grain sizes than ZnO,which in turn meant larger specific surface area and pore volume.Chemical defects were also produced,which facilitated photocatalytic activity,because such defects can act as reaction centers.The optical band gap magnitude and the diamagnetic nature of YZO were also determined.The structural,crystalline,and chemical defects of YZO synergistically enhanced the photocatalytic degradation of carbaryl;indeed,the kinetic rate constant of this reaction catalyzed by YZO was 11.17×10^(−2) min^(−1) under natural sunlight irradiation,higher than the value measured for ZnO(8.68×10^(−2) min^(−1)).Evidence thus indicates that yttrium-doping effectively modified some properties of ZnO nanoparticles so that YZO nanoparticles proved a suitable photocatalytic material for carbaryl degradation.

甲萘威的环境暴露与毒性研究进展

甲萘威是一种重要的氨基甲酸酯类杀虫剂,能防治多种害虫,被广泛应用于多种农作物的生产活动中。在鹿特丹公约化学品审查委员会第17次会议(CRC17)、18次会议(CRC18)和19次会议(CRC19)上,多次审议了甲萘威是否满足公约要求,尤其是风险评估的数据是否充分,委员会均未能达成一致,该产品将在CRC20上继续审议。基于此,本文总结了甲萘威的结构、理化性质、环境暴露及其毒性健康风险研究,其中毒性包括急性毒性与短期毒性、长期毒性与基因毒性、生殖毒性与发育毒性、生态毒性等,旨在为更好地保障粮食安全、农产品质量安全和环境安全等提供科学的数据支撑和借鉴。

Analysis of Carbaryl Pesticide Residues in Environmental Samples with Spectrophotometry

A facile, rapid and sensitive spectrophotometric method was developed for the determination of carbaryl in its formulations, water and grain （rice and wheat） samples with newly synthesised reagent. The proposed method was based on the alkaline hydrolysis of carbaryl pesticide and thus resulted 1-naphthol was coupled with diazotised 4,4＇-methylene-bis-m-nitroaniline in basic medium （pH 9） to give red colored product having λmax 480 nm for diazonium method （DM） or 1-naphthol reacts with 4,4＇-methylene-bis-m-nitroaniline in the presence of oxidising agent potassium dichromate （K2Cr2O7） to give red colored product having λmax 510 nm for oxidation method （OM）. The formation of colored derivatives with the coupling agent is instantaneous and stable for 48 h （DM） and 32 h （OM） respectively. Beer＇s law was obeyed in the concentration range of 0.2--10.0 μg·mL ^-1 for DM and 0.2--0.150 μg·mL^-1 for OM. The proposed methods are sensitive, easy to operate and permitted for the determination of carbaryl with detection limits of 0.028 μg·mL^-1 for DM and 0.024 μg·mL^-1 for OM respectively. The experimental results indicate that the procedure can eliminate the fundamental interferences caused by other pesticides and non-target ions, which made the methods more sensitive and selective. The method was applicable to the determination of carbaryl residue in water and food grain samples up to μg level.

Selection of a DNA aptamer for the development of fluorescent aptasensor for carbaryl detection

An improved ssDNA library immobilized systematic evolution of ligands by enrichment(SELEX)was applied to select aptamers against carbaryl.After nine selection rounds,a highly enriched ssDNA pool was obtained.The Apta3 was demonstrated as the optimal aptame r.In order to facilitate the modification of aptamer,the Apta3 was further truncated with the dissociation constant(K_(d))of 0.364±0.055μmol/L and a fluorescent aptasensor was developed.The linear range for carbaryl was from 100 nmol/L to1500 nmol/L,with the limit of detection was as low as 15.23 nmol/L.Besides,the biosensor was validated for the carbaryl spiked real samples,and the recoveries were between 97.7%and 107.3%.

HPLC-MS/MS直接进样法测定环境水体中阿特拉津和甲萘威

采用HPLC-MS/MS直接进样方式,建立了一种适用于生活饮用水及其水源水等环境水体中甲萘威和阿特拉津的快速测定方法。本方法与现行环境保护标准相比,具有灵敏度高、操作简便、出峰时间快等优势。实验结果表明:甲萘威和阿特拉津的检出限分别为0.07μg/L和0.08μg/L,甲萘威相关系数达0.999 7,阿特拉津相关系数达0.999 6,方法精密度在2.72%~10.32%之间,加标回收率结果在87.5%~120.5%之间。该方法线性相关系数高、方法检出限低、精密度和准确度均满足环境水体中特定项目分析要求,方法准确可靠,且只需将样品过滤及稀释后即可上机测定,免去了液液萃取或固相萃取等浓缩步骤,极大地缩短了样品预处理和分析测试时间,快速简便。

Synthesis, Characterization and Application of Organic-inorganic Hybrid and Carbaryl-imprinted Capillary Monolithic Column

Organic-inorganic hybrid and carbaryl-imprinted capillary monolith was synthesized via methacrylic acid（MAA） as functional monomer, γ-methacryloxypropyltrimethoxysilane（γ-MAPS） as crosslinker and carbaryl as template molecule in an acetonitrile/dichloromethane mixture（1：4, volume ratio）. With the capillary column obtained from this monolith, three carbamates（carbaryl, fenobucarb and metolcarb） were separated effectively by electrochromatography with the kMIp/kNlP values of 7.57, 1.27 and 1.64, respectively. In 20 mmol/L phosphate buffer solution（pH=3.5） with 30%（volume fraction） of acetonitrile, carbaryl was separated directly from the three-carbamate mixture（carbaryl, fenobucarb and metolcarb） with an effective 15 cm-length imprinted column.

超高效液相色谱串联质谱法筛查款冬花中135种农药残留及其风险评估

目的采用超高效液相色谱串联质谱技术对款冬花中135种农药残留进行筛选。方法供试品采用乙腈为提取溶剂,高速匀浆提取;CORTECSTM UPLC C18(1.6μm,2.1 mm×150 mm)色谱柱,流动相:流动相以0.1%甲酸水溶液(含5 mmol·L^(-1)甲酸铵)为水相,以95%乙腈水溶液(含0.1%甲酸和5 mmol·L^(-1)甲酸铵)为有机相梯度洗脱;流速0.3 mL·min^(-1)、柱温40℃、进样量为2μL。电喷雾离子源,多反应监测模式,以标准曲线法计算含量。采用慢性暴露评估法计算慢性风险商(HQc)。结果135种农药的回收率为70.30%~118.45%,相对标准偏差小于9.1%,各测定组分在1~100 ng·mL^(-1)范围内呈良好的线性关系(r≥0.99)。27批样品中,7批检出毒死蜱,1批检出腈菌唑,1批检出甲萘威。所有批次HQc均远小于1,款冬花的农药残留风险较低。结论该方法全面、准确、快速,适合款冬花中135种农药残留的高通量测定及风险评估,对其他中药材农药残留的检测也具有参考意义。

高灵敏西维因适配体传感器的制备

针对农药的滥用与残留对人体和环境造成的严重危害,亟需一种快速、灵敏的现场检测方法。采用特异性好的西维因核酸适配体和聚赖氨酸(PLL)修饰黑磷纳米片(BPNSs)构建适配体传感器,并采用差分脉冲伏安法(DPV)评估适配体传感器的性能。结果显示,其线性方程为:ΔI(μA)=11.71 lgC+21.62,线性范围为0.1 ng/mL~10μg/mL,线性相关系数R^(2)=0.998,检出限为83.47 pg/mL。该适配体传感器具有重复性好、稳定性强及特异性高的优点。

山药粉中甲萘威残留分析基体标准物质研制

目的:加强农产品流通监管,开发食品检测方法。方法:通过模拟种植方式获得含甲萘威的山药阳性样本,经过均质、冷冻干燥、粉碎、过筛、混匀、包装制备山药粉。采用液相色谱-串联质谱仪检测,同位素内标-标准曲线法定量。通过对均匀性、稳定性、协同定值、不确定度的评定,得到满足预期含量水平的山药粉中甲萘威基体标准物质。结果:该方法所制备的基体标准样的特性值为(1.04±0.10)mg/kg(k=2)。结论:采用冷冻干燥法制备的山药粉中甲萘威基体标准物质符合国家计量技术规范中均匀性、稳定性要求,可用于食品实验室方法验证、质量控制等活动。

毛豆壳生物炭的活化及其对甲萘威的吸附性能

以KOH为活化剂,优化毛豆壳活化生物炭(A-SBC)的制备条件,研究不同体系对A-SBC吸附甲萘威的影响,分析A-SBC对甲萘威的吸附动力学、热力学特性,以期为实现毛豆壳的资源化利用和控制甲萘威农药的环境污染提供理论依据和技术支撑。结果表明:将毛豆壳在700℃、1 h预碳化后,与KOH按1∶2.0的质量比混合,在750℃、1.5 h的条件下活化,获得的A-SBC对甲萘威的吸附性能最佳,吸附率达89.63%,吸附容量为113.28 mg·g^(-1)。与未经活化的毛豆壳生物炭相比,A-SBC的表面凹陷,孔隙密集,有机官能团减少。当体系pH为2.0~6.5时,A-SBC对甲萘威的吸附良好,并在pH值为5.5时吸附容量最大;A-SBC对甲萘威的吸附随温度升高而增多,在离子强度(NaCl)为0.01 mol·L^(-1)时吸附容量最大。A-SBC对甲萘威的吸附更符合准二级动力学模型,等温吸附曲线更适于用朗缪尔(Langmuir)方程拟合,说明其以化学吸附为主。吸附热力学结果表明,A-SBC对甲萘威的吸附由疏水作用主导,是自发的吸热反应。A-SBC对甲萘威的吸附性能优良,可为去除水体环境中的甲萘威污染提供新途径与新材料。

超高效液相色谱-三重四极杆质谱快速测定地表水中甲萘威、微囊藻毒素-LR、溴氰菊酯

基于超高效液相色谱-三重四极杆串联质谱技术(UPLC-MS/MS),建立了一种经简单过滤即可直接进样测定地表水中甲萘威、微囊藻毒素-LR、溴氰菊酯的分析方法。水样过0.22μm微孔滤膜后,经C18色谱柱(1.8μm,2.1 mm×50 mm),柱温40℃,流速0.3 mL/min,以甲醇和2 mmol/L乙酸铵水溶液(含0.1%甲酸)为流动相进行梯度洗脱;采用电喷雾正离子电离(ESI+),多反应监测模式(MRM)检测,外标法定量分析目标物。方法学验证结果表明3种目标物浓度在0.20~50.0μg/L范围线性关系良好,相关系数(R^(2))>0.9990,方法检出限为0.03~0.08μg/L,目标物平均加标回收率为89.3%~116%,相对标准偏差(RSD)为0.5%~9.6%(n=6)。所建立方法简便快捷、灵敏准确,适用于地表水中3种有机污染物同时快速测定。

高效液相色谱—质谱联用法测定苹果中9种氨基甲酸酯及其代谢物农药残留量

本文研究了甲奈威、灭多威、异丙威、抗蚜威、克百威(3-羟基克百威)、涕灭威(涕灭威砜、涕灭威亚砜)在苹果上的残留量,建立了使用液质联用仪同时检测的方法,样品提取液中加入无水MgSO_(4),NaCl,柠檬酸钠后振摇离心,上清液中加入无水MgSO_(4)和PSA,继续振摇离心,上清液过膜上机检测,大大降低了干扰,提高了检测的灵敏度。该方法操作简单、快速、灵敏度高。

甲维盐提纯工艺优化研究

为有效提升甲维盐纯度和收率,文章通过优化溶解剂、萃取剂、萃取压力、萃取温度、萃取时间、分离压力、分离温度等纯化条件,探究其对甲维盐成品纯度和收率的影响。结果显示甲维盐粗品用乙醇溶解,加入乙酸乙酯进行萃取,萃取压力为30 Pa,萃取温度为40℃,萃取时间为2.5 h,静置分层并分离,分离压力4 Pa,分离温度为40℃,获得萃取液,最后进行浓缩结晶即可,获得甲维盐的收率和纯度均有所提升。

猪粪制备的生物炭对西维因的吸附与催化水解作用

以猪粪为原料,在不同温度下制备生物炭,并对其进行除灰处理,研究了不同处理温度和灰分含量的生物炭与西维因的相互作用。猪粪制备的生物炭含有无机矿物、不定型有机质和结晶态芳香碳,且随处理温度升高,灰分含量增加,BET比表面积增加。生物炭对西维因的吸附表现为非线性,等温线符合Freundlich方程,且随生物炭制备温度的升高,非线性增强。生物炭除灰后,吸附作用大大增强,表明有机碳与无机成分复合造成其一部分吸附点位的损失。生物炭对西维因的吸附由亲脂性分配与特殊作用力构成,随着生物炭不同以及西维因浓度的变化,吸附机制发生变化。生物炭可提高溶液pH,pH随生物炭添加量和处理温度而升高,生物炭含有的矿物对西维因水解具有催化作用,其水解速率及程度与生物炭灰分含量呈正相关。