Organophosphates and carbamates

Organophosphates and carbamates containing a pyrazole ring, useful as insecticides as discussed earlier (Section 4.04.4.1.2), are metabolized mainly through hydrolysis of the ester function (B-80MI40406). 

Toxin (Enzyme Inhibition) Biosensors Enzyme affectors (inhibitors and activators) that influence the rate of biocatalytic reactions can also be measured. Sensing probes for organophosphate and carbamate pesticides, for the respiratory... 

Aaron CK, Howland, MA. 1998. Insecticides Organophosphates and carbamates. In Goldfrank LR, Flomenbaum NE, Lewin NA, et al., eds. Goldfiank s toxicologic emergencies. Stamford, CT Appleton Lange, 1429-1449. 

Senanayake N, Karalliedde E. 1992. Intermediate syndrome in anticholinesterase neurotoxicity. In Ballantyne B, Marrs TC, ed. Clinical and experimental toxicology of organophosphates and carbamates. Jordan Hill, Oxford, England Butterworth-Heinemann Etd., 57-62. 

Ballantyne, B. and Marrs, T.C. (1992). Clinical and Experimental Toxicology of Organophosphates and Carbamates, Butterworth/Heinemann, Oxford—Gives an in-depth account of the toxicology of both groups of compounds including some information about the so-called nerve gases. 

Misra, U.K. (1992). Neurophysiological monitors of anticholinesterase exposure. In B. Ballantyne and T.C. Marrs. (Eds.) Clinical and Experimental Toxicology of the Organophosphates and Carbamates 446-459. 

Chohnesterase-inhibiting pesticides (e g., organophosphate and carbamate pesticides) are detected by dipping the developed chromatogram in a solution of the enzyme chohnesterase followed by incubation for a short period. Then the plate is dipped in a substrate solution, e.g., 1-naphthyl acetate/fast blue salt B. In the presence of the active enzyme, 1-naphthyl acetate is hydrolyzed to 1-naphthol and acetic acid, and the 1-naphthol is coupled with fast blue salt B to form a violet-blue azo dye. The enzyme is inhibited by the pesticide zones, so the enzyme-substrate reaction does not occur pesticides are, therefore, detected as colorless zones on a violet-blue background [36]. 

Organophosphate and carbamate pesticides are potent inhibitors of the enzyme cholinesterase. The inhibition of cholinesterase activity by the pesticide leads to the formation of stable covalent intermediates such as phosphoryl-enzyme complexes, which makes the hydrolysis of the substrate very slow. Both organophosphorus and carbamate pesticides can react with AChE in the same manner because the acetylation of the serine residue at the catalytic center is analogous to phosphorylation and carbamylation. Carbamated enzyme can restore its catalytic activity more rapidly than phosphorylated enzyme [17,42], Kok and Hasirci [43] reported that the total anti-cholinesterase activity of binary pesticide mixtures was lower than the sum of the individual inhibition values. 

S. Jin, Z. Xu, J. Chen, X. Liang, Y. Wu, and X. Qian, Determination of organophosphate and carbamate pesticides based on enzyme inhibition using a pH-sensitive fluorescence probe. Anal. Chim. Acta 523, 117-123 (2004). 

Kikuchi, H., Y. Suzuki, and Y. Hashimoto. 1981. Increase of (3-glucuronidase activity in the serum of rats administered organophosphate and carbamate insecticides. Jour. Toxicol. Sci. 6 27-35. 

Meier, E.R, M.C. Warner, W.H. Dennis, W.F. Randall, and T.A. Miller. 1976. Chemical Degradation of Military Standard Formulations of Organophosphate and Carbamate Pesticides. I. Chemical Hydrolysis of Diazinon. U.S. Army Med. Bioengin. Res. Dev. Lab., Fort Detrick, Frederick, MD. Tech. Rep. 7611. 32 pp. 

It should be noted that space permits only one sample of District Chief Armando Bevelac-qua work. However, his production also includes medical protocols for Bronchospasms, Tachydysrhythmias, Chemical Burns, Carbon Monoxide, Nitrogen Compounds, Cyanide and Hydrogen Sulfide, Organophosphate and Carbamate (Nerve Agents), Hydrofluoric Acid, Phenol, Chloramine and Chlorine Products, Lacrimators, and Phosgene. 

In the 1960s and 1970s, the organophosphate and carbamate compounds replaced the chlorinated hydrocarbons as the most prominently used insecticides. These two families of insecticides share a common toxicological mechanism, the inhibition of cholinesterase enzymes in the nervous systems of... 

Chemical degradation has been investigated by Shlh and Dal Porto Q) and by Lande ( ) under EPA auspices as an alternative approach (to landfill disposal) for the removal of pesticide residues. Among candidate reactions for the safe detoxification of pesticides, only alkaline hydrolysis was recommended. Several organophosphates and carbamates were identified as amenable to a degradation procedure using strong base/aqueous alcohol. The... 

Acetyl cholinesterase activity AChE,. brain Neurotoxic parameter Organophosphate and carbamate pesticides Brain tissue 13-15... 

AChE, muscle Organophosphate and carbamate pesticides Muscle tissue 10-15... 

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