Organophosphorous-based

Generation lib. After the problems of the chlorinated organics became clear, the chemical and agricultural industry went to organophosphorous-based compounds. Although these compounds are not particularly long lived in the environment, they are more toxic to mammals as compared to the chlorinated compounds. 

Wash-resistant synthetic textiles (e.g., polyester and polyamide) can be obtained by using organophosphorous-based FRs. 

K. Rekha, M.D. Gouda, M.S. Thakur, and N.G. Karanth, Ascorbate oxidase based amperometric biosensor for organophosphorous pesticide monitoring. Biosens. Bioelectron. 15, 499-520 (2000). 

Neurotoxicants, immunotoxicants, and teratogens were also further explored, and it was concluded that, except for the organophosphorous neurotoxicants, such compounds would be covered by the stmcmre-based, tiered TTC approach. For organophosphates, a human exposure threshold of... 

Legierse, K. C. H. M., W. H. J. Vaes, T. Sinnige, and J. L. M. Hermens, Distribution of chlorobenzenes and the organophosphorous pesticide chlorthion in the pond snail (Lymnaea stagnalis) A multi-compartment model based on partitioning to polar lipids, neutral lipids and pond snail protein, Ph.D. thesis, University of Utrecht, Utrecht, 1998,... 

Bowman and Sans [12] measured Kow and water solubilities at 20°C for liquid and solid carbamates and organophosphorous insecticides and related compounds. Based on these data, they derived the following equation ... 

Accelerated solvent extraction is a new technique for the extraction of a range of organic pollutants from soils and related material. The technique is based on the use of a solvent or combination of solvents to extract organic pollutants at elevated pressure and temperature from a solid matrix. The range of organic pollutants for which the technique is proposed includes semi volatile compounds, organochlorine pesticides, organophosphorous pesticides, chlorinated herbicides, polychlorinated biphenyls and polycyclic aromatic hydrocarbons [66-69]. 

The phosphoric acid triesters (organophosphates, not to be mistaken for organophosphorous pesticides) are, like phthalates, plasticizers mixed into polymers to increase flexibility and workability. Unlike phthalates they are remarkable flame retardants as well. The total European production of phosphorous-base flame... 

This system is also used for detection of supertoxins and chemical war gases based on organophosphorous compounds, responsible for the blocking of acetyl cholinesterase in the central nerve system. The system of enzymatic reactions used for the brief analysis of such substances is the following [4] ... 

Arribas, A.S., Vazquez, T., Wang, J., Mulchandani, A., Chen, W. (2005). Electrochemical and optical bioassay of nerve agents based on the organophosphorous-hydrolase mediated growth of cupric ferrocyanide nanoparticles. Electrochem. Commun. 7 1371-4. 

Organophosphoric esters are very effective and degradable pesticides [304], which makes them preferable to their chlorine-based counterparts. Their hydrolysis behavior is well known [305], the final product being the orthophosphate ion. But these compounds are very toxic to humans because of their inhibiting effect on acetylcolinesterase as little as a few ppm can be lethal [306]. 

Enzymatic based devices have been widely reported for the detection of organic pollutants (see Table 3.2.4). The selective inhibition of choline esterases, principally acetylcholine esterase (AchE) (Guibault and Das, 1970), and butylcholine esterase (BchE) (Skladal, 1992), have been used for the detection of organophosphorous, and carbamate insecticides. However, there are some limitations. 

Bruce (1967) deveioped a method based on a gas chromatograph equipped with a specially constructed electron capture cell. This detector cell was claimed to allow the determination of extremely low quantities (picogram levels) of organophosphorous and pyrethroid insecticides, as well as synergists in food, feeds and water Moore (1972) analysed PBO residues in different foodstuffs (oils and fats, potato chips, bacon, chicken and eggs, dried codfish) by means of the Bruce gas chromatographic method. 

Grimsley, J.K., W.R Singh, J.R. Wild, and A. Giletto. 2001. A novel, enzyme-based method for the wound-surface removal and decontamination of organophosphorous nerve agents. Pp. 35-49 in Bioactive Fibers and Polymers, ACS Symposium Series No. 742. J.V. Edwards and T.L. Vigo, eds. New York, N.Y. Oxford University Press. 

Based on the EPI generated values for solubility (log Sol), octanol-water partitioning (log Kow), vapour pressure (log VP) and Henry s Law constants (log HLC) new linear QSAR models are build by estimating the relationships between the EPI generated data and available experimental data for up to 65 organophosphor insecticides, the general formula for the descriptors, Du to be used being... 

Stark and Sherman (1989) developed toxicity data for the 3 tephritid fruit fly species mentioned earlier after exposure to the organophosphorous insecticide, acephate. They found that the oriental fruit fly was the most susceptible species, followed by the melon fly and Mediterranean fly (Table 5.1). Although these are pest species, for this example I will consider them to be beneficial species and invent an EEC of 1 pg/g. Quotient ratios based on the LD50 and the above-mentioned EEC indicate that acephate poses a hazard only to the oriental fruit fly (Table 5.1). 

Kawagoshi Y, Fukunaga I, Itoh FI (1999) Distribution of organophosphoric acid triesters between water and sediment at a sea-based solid waste disposal site. J Material Cycl Waste Management 1, 53-61. 

An enzyme-based Pz biosensor for the detection of organophosphorous and carbamate pesticides has also appeared [176]. The assay was based in the inhibitory effect of the pesticides on immobilised acetylcholinesterase. After exposure of the enzyme to the pesticides, the substrate 3-indoyl acetate was added. This was enzymatically converted to an insoluble product, the concentration of which was determined by the resulting frequency change. The rate and amount of conversion was due to the concentration of the active immobilised enzyme, which was dependent on the amount of pesticide present. The system was very similar to that used by Ebersole and Ward in their AMISA [66]. The authors measured paroxon to 5 x 10 M and carbaryl to 1 X 10- M. 

Everett W. R. and Rechnitz G. A., Enzyme-based electrochemical biosensors for determination of organophosphorous and carbamate pesticides, Anal. Lett., 32, 1-10, 1999. 

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