Carbamate pesticide, solid

UN No. 1133 ADHESIVES UN No. 1266 PEREUMERY PRODUCTS UN No. 2757 CARBAMATE PESTICIDE, SOLID,TOXIC UN No. 3101 ORGANIC PEROXIDE TYPE B, LIQUID... 

McGarvey [304] has reviewed high-performance liquid chromatographic methods of determining 31 AT-methylcarbamate pesticides in soil, and Oka-moto et al. [305] used automated solid-phase extraction followed by on-line high-performance liquid chromatography to determine ten carbamate pesticides in soil. 

Nerve Agents are the most toxic of the known chemical agents. Solids, liquids or vapors from these agents are hazardous and can cause death within minutes after exposure. Nerve Agents disrupt the function of the nervous system by interfering with the enzyme acetylcholinesterase. The major effects will be on skeletal muscles, certain organs, and the central nervous system. These compounds are similar to, but much more deadly than, agricultural carbamate pesticides. 

Carbamate pesticides can be either solids or liquids with varying colors and odors. These pesticides are also found as solutions. 

The procedure to be used to extract carbamate pesticides from environmental samples depends on their polarity and on the type of sample matrix involved. Various choices exist for the extraction of pesticides ranging from conventional procedures (e.g., Soxhlet extraction, liquid-liquid extraction (LLE), evaporation, steam distillation) to new methodologies including solid-phase extraction (SPE), solid-phase microextraction (SPME), supercritical fluid extraction (SEE), matrix solid-phase dispersion (MSPD), accelerated solvent extraction (ASE) and microwave-assisted extraction. " ... 

LLE is a widely used technique among the official US-EPA methods for the preconcentration of pesticides in liquid samples. Nonpolar solvents for the LLE of pesticides include w-hexane, benzene, and ethyl acetate. Water-miscible solvents for this purpose include dichloromethane, methanol, acetonitrile, acetone, and water, which have been employed for the extraction of residues from high-moisture commodities. Mixed solvents have often been used to finely adjust the solvent strength. Thus, various carbamate pesticides were extracted from aqueous environmental samples with chloroform and determined by HPLC with a mean recovery of 71 Also, a method based on the extraction by sonication of solid samples placed in small columns with a low volume of ethyl acetate was developed for the extraction of thiocarbamates and other herbicides from soil with recoveries between 89 and 109%. ... 

Number of carbamate pesticides (see Table 24.1) other other noncarbamate pesticides LLE liquid-liquid extraction SPE solid-phase extraction... 

Soriano, J. M., Jimenez, B., Font, G., and Molto, J. C., Analysis of carbamate pesticides and their metabolites in water by solid phase extraction and liquid chromatography a review, Crit. Rev. Anal. Chem., 31, 19-52, 2001. 

Slobodnik, J., Hoekstra-Oussoren, S. J. F., Jager, M. E., Honing, M., van Baar, B. L. M., and Brinkman, U. A. Th., Online solid-phase extraction-liquid chromatography-particle beam mass spectrometry and gas chromatography-mass spectrometry of carbamate pesticides. Analyst, 121, 1327-1334, 1996. 

Yang, R. Z, Wang, J. H., Wang, M. 1., Zhang, R., Lu, X. Y., and Liu, W. H. 2011. Dispersive solid-phase extraction cleanup combined with accelerated solvent extraction for the determination of carbamate pesticide residues in radix glycyrrhizae samples by UPLC-MS-MS. J. Chromatogr. Sci. 49 702-708. 

Carabias-Martinez, R. et al.. Behavior of carbamate pesticides in gas chromatography and their determination with solid-phase extraction and solid-phase microextraction as preconcentration steps, /. Sep. Sci., 28, 2130, 2005. 

SFE. SFE has been established as the extraction method of choice for solid samples. The usefulness of SFE for soil samples has been demonstrated for carbamate,organophosphorus and organochlorine pesticides. However, SFE is more effective in extracting nonpolar than polar residues. In order to obtain a greater extraction efficiency for the polar residues of imidacloprid, the addition of 20% methanol as modifier is required. Extraction at 276 bar and 80 °C with a solvent consisting of supercritical carbon dioxide modified with methanol (5%) for 40 min gives a recovery of 97% (RSD = 3.6%, n = 10). It is possible to use process-scale SFE to decontaminate pesticide residues from dust waste. ... 

Solid-phase microextraction (SPME), e.g., for the determination of carbamate and triazine pesticides from water, soil leachates, and slurries [85-87]. 

Sagratini, G., Manes, J., Giardina, D., Damiani, P., and Pico, Y. (2007). Analysis of carbamate and phenylurea pesticide residues in fruit juices by solid-phase microextraction and hquid chromatography-mass spectrometry, J. Chromatogr. A, 1147,135-143. 

Carbary I (1-naphthyl methylcarbamate) is a chemical in the carbamate family used chiefly as an insecticide. It is a colorless white crystalline solid. Carbaryl disrupts the nervous system by adding a carbamyl moiety to the active site of the acetylcholinesterase enzyme, which prevents it from interacting with acetylcholine.1 It is classified as a likely human carcinogen by the EPA. The pesticide is used indiscriminately, so the toxicity has raised public concern about the ecosystem and human health. Carbaryl is lethal to many non-target insects such as the honeybee. Accumulation of the pesticide occurs in many aquatic organisms such as catfish and algae.2 Due to public health and ecosystem concerns a number of analytical procedures have been used to determine carbaryl concentrations. 

MSPD involves blending a solid sample with solid particles, which simultaneously disrupt and disperse the sample. The underlying mechanisms of MSPD include sample homogenization, cellular disruption, exhaustive extraction, fractionation, and purification in a simple process. One carbamate (pirimicarb) and 12 organophosphorus pesticides were extracted by MSPD from honey, the sample was mixed with Florisil and anhydrous sodium sulfate in small glass columns, and subsequently extracted with a volume of n-hexane-ethyl acetate. ... 

Apart from modified silica gel, the most frequently used solid-phase adsorbents are activated charcoal, macroreticular resins (XAD), ordinary silica gel, aluminum oxide, and Florisil. Activated charcoal is a universal adsorbent for concentrating trace organic materials in aqueous solutions and air, XAD resins are also commonly employed for extracting organic trace constituents, such as alkoxyacetic acids [1.57], organochlorine pesticides [200], [218], carbamates [198], 202j, and triaz.ines [218] from aqueous matrices. 

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