Organophosphates applications

Application of the CCM to small sets (n < 6) of enzyme inhibitors revealed correlations between the inhibitory activity and the chirality measure of the inhibitors, calculated by Eq. (26) for the entire structure or for the substructure that interacts with the enzyme (pharmacophore) [41], This was done for arylammonium inhibitors of trypsin, Di-dopamine receptor inhibitors, and organophosphate inhibitors of trypsin, acetylcholine esterase, and butyrylcholine esterase. Because the CCM values are equal for opposite enantiomers, the method had to be applied separately to the two families of enantiomers (R- and S-enantiomers). 

Mental disturbances have been reported after organophosphate exposure. Neuropsychiatric symptoms occurred in two aerial applicators, one of whom used methyl parathion as well as other insecticides. One of these pilots had high levels of exposure to a mixture containing methyl parathion, toxaphene, and Dipterex when his clothing became saturated when the tank of his aircraft accidentally overflowed. Several months after the accident, the subject complained of anxiety, dizziness, emotional lability, and frequent and severe disagreements with family members and associates. Similar observations had been... 

Wolfe NL. 1980. Organophosphate and organophosphorothionate esters Application of linear free energy relationships to estimate hydrolysis rate constants for use in environmental fate assessment. Chemosphere 9 571-579. 

Organophosphate Ester Hydraulic Fluids. Repeated application of a patch treated with 0.2 pL of Skydrol 500B-4 for 5 weeks (3 times/week) resulted in mild cumulative erythema confined to the contact site in 14 of 53 human test subjects, beginning with the third dose during the first week. No evidence of immediate primary dermal irritation was observed (Monsanto 1980). 

Organophosphate Ester Hydraulic Fluids. Organophosphate ester hydraulic fluids are used in applications that require a degree of fire resistance such as in aircraft. EPA (1992b) has noted that aircraft mechanics may have dermal exposures of 1,300-3,900 mg/day and that 2,200 aircraft workers are routinely exposed to tributyl phosphate, while another 43,000 mechanics may be exposed at various times. Estimates of worker exposure in other industries were not found in the available literature. General population and military personnel exposure to organophosphate ester hydraulic fluids is likely to be much lower than exposure to mineral oil hydraulic fluids because these fluids have more specialized uses. 

Similarly, organophosphate esters are used in a wide variety of applications including hydraulic fluids, plasticizers, and antiwear additives to hydraulic fluids and engine oils. All of these uses have the potential to contaminate the environment, and all of the organophosphate ester components present in hydraulic fluids also are present in plasticizers and antiwear additives. Therefore, detection of a particular organophosphate ester in the environment or in biological media cannot identify the source of the contamination (i.e., hydraulic fluids, plasticizers, antiwear additives). 

Kaemmerer, K. and S. Buntenkotter. 1973. The problem of residues in meat of edible domestic animals after application or intake of organophosphate esters. Residue Rev. 46 1-240. 

Bergh C, Torgrip R, Ostman C (2010) Simultaneous selective detection of organophosphate and phthalate esters using gas chromatography with positive ion chemical ionization tandem mass spectrometry and its application to indoor air and dust. Rapid Commun Mass Spectrom... 

Diazinon Organophosphate 333-41-5 1.14 1953 Insectic. An insecticide used to control sucking and chewing insects on a wide range of crops including top fruit. It also has livestock applications... 

The TGD (EC 2003) contains a section on specific system/organ toxicity, which includes a section concerning guidance on investigation of neurotoxicity and EU-specific risk assessment. Eor the evaluation of organophosphate pesticides, it has been agreed to use the WHO/FAO JMPR recommendations (FAO 1998, 1999) (Section 4.7.7.3.1) as the applicability of these recommendations also can be extended to biocides and new/existing substances. 

Methyl parathion is used primarily on cotton. It was one of the first insecticides restricted under the 1996 Food Quality Protection Act (FQPA), which developed new safety standards for human health, especially that of children. It can no longer be used on many fruits and vegetables. Malathion and parathion are the broadest spectrum organophosphate insecticides. There are many other organophosphate insecticides in use in the U.S. today. Many are produced at the 1-5 million Ib/yr level for specific applications. Three other leading organophosphates besides those mentioned already are chlorpyrifos, terbufos, and phorate. 

There is some USEPA precedent for use of statistical meta-analysis in a regulatory context, including the recent meta-analysis of organophosphate-related acetylcholinesterase inhibition data and meta-analysis of epidemiological studies on effects of 2nd hand tobacco smoke exposure. Warren-Hicks and Moore (1998) provide some discussion of the potential applicability of meta-analysis to ecological risk assessments. 

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