Isofenphos

Ethyl hydrogen fumarate, see Malathion 0-Ethyl hydrogen-A-isopropylphosphoramidate, see Isofenphos... 

Isocyanatopropane, see Atrazine Isofenphos oxon, see Isofenphos Isoheptane, see PCB-1242 Isohexane, see PCB-1242 Isononane, see PCB-1242 Isononanes, see Octane Isooctane, see PCB-1242 Isooctanes, see Octane Isophthalic acid, see ro-Xylene Isopropoxyphenol, see ProDoxnr Isopropyl alcohol, see Isopropyl acetate Isopropylatnide, see Bentazone IV-Isopropylaniline, see Propachlor Isopropylbenzene, see Propylbenzene, PCB-1242,... 

Isopropyl salicylic acid, see Isofenphos p-Ketoadipic acid, see Aniline, Diethyl phthalate, Hydroquinone... 

CASRN 25311-71-1 molecular formula C15H24NO4PS FW 345.40 Soil. Rapidly degraded by microbes via oxidative desulfuration in soils forming isofenphos oxon (Abou-Assaf et al, 1986 Abou-Assaf and Coats, 1987 Somasundaram et al., 1989), isopropyl salicylate, and carbon dioxide (Somasundaram et al., 1989). The formation of isofenphos oxon is largely dependent upon the pH, moisture, and temperature of the soil. The degradation rate of isofenphos decreased with a decrease in temperature (35 °C >25 °C >15 °C), moisture content (22.5% >30% >15%), and in acidic and alkaline soils (pH 6 and 8). After isofenphos was applied to soil at a rate of 1.12 kg ai/ha, concentrations of 8.3, 7.2, 5.1, and 1.0 ppm were found after 5, 21, 43, and 69 d, respectively. Following a second application, 4.9, 1.55, 0.25, and 0.10 ppm of isofenphos were found after 5, 21, 43, and 69 d, respectively (Abou-Assaf and Coats, 1987). 

A pure culture of Arthrobacter sp. was capable of degrading isofenphos at different soil concentrations (10, 50, and 100 ppm) in less than 6 h. In previously treated soils, isofenphos could be mineralized to carbon dioxide by indigenous microorganisms (Racke and Coats, 1987). Hydrolyzes in soil to salicylic acid (Somasundaram et al., 1991). 

Abou-Assaf, N., Coats, J.R., Gray, M.E., and Tollefson, J.J. Degradation of isofenphos in cornfields with conservation tillage practices,/. Environ. Sci. Health, B21(6) 425-446, 1986. 

Dureja, P.S.W. and Mukerjee, S.K. Photodecomposition of isofenphos [0-Ethyl-0-(2-isopropoxycarbonyl)phenyl]isopropyl-phosphoramidothioate, Toxicol Environ. Chem., 19(3-4) 187-192, 1989. 

Racke, K.D. and Coats, J.R. Enhanced degradation of isofenphos by soil microorganisms, / Agric. Food Chem., 35(l) 94-99, 1987. 

Sears, M.K., Bowhey, C., Braun, H., and Stephenson, G.R. Dislodgable residues and persistence of diazinon, chlorp3uifos and isofenphos following their application to turfgrass. Pestle. Scl, 20(3) 223-231, 1987. 

Lemmon CR, Pylypiw HM, Jr. 1992. Degradation of diazinon, chlorpyrifos, isofenphos, and pendimethalin in grass and compost. Bull Environ Contam Toxicol 48 409-415. 

Chlorpyriphos methyl, diazinon, disulfoton, fenamiphos, fenthion, isofenphos, malathion, methidathion, pyridafenthion, temephos... 

Fig. 4 Chromatograms of a blank apple sample (top) and the same apple sample spiked with 27 of the 31 organophosphorus at the following concentration levels (bottom). 1 = paraoxon methyl 500 2 = malaoxon 6400 3 = paraoxon ethyl 800 4 = metidathion 500 5 = azinphos-methyl 200 6 = phosmet 200 7 = parathion methyl 800 8 = malathion 2000 9 = triazophos 200 10 = fenitrothion 800 11= azinphos ethyl 200 12 = chlorfenvinphos 200 13 = quinalphos 200 14 = parathion-ethyl 400 16 = ethrimphos 1000 17 = diazinon 800 18 = coumaphos 800 19 = fonophos 200 21 = phoxim 400 23 = chlorpyriphos-methyl 500 24 = disulfoton 2000 26 = isofenphos 500 27 = fenchlorphos 500 28 = temephos 400 29 = chlorpyriphos ethyl 200 30 = pyrimiphos-ethyl 200 31 = carbophenothion-ethyl 400. The chromatography was carried out with the Altima column using CH3CN/H20 as mobile phase in gradient elution CHjCN from 28 to 39% in 20 min, and then from 39 to 88% in 40 min. (From Ref. 59.)...

Toxicity The acute oral LD50 of isofenphos for rats ranges from 20 to 125 mg/kg, and the acute dermal LD50 for rats is 70 mg/kg. The acute LC50 for rats is 0.144 mg/L and 1.3 mg/L. The acute inhalation LC50 (4 hours) for hamsters is 0.23 mg/L. These values indicate that the compound is highly toxic to organisms and humans who inhale even small amounts of isofenphos. In combination with malathion, isofenphos becomes extremely toxic.65,67... 

R.K. Broadberg, Estimation of Exposure of Persons in California to Pesticide Products Containing Isofenphos, California Department of Food and Agriculture, Division of Pest Management, Sacramento, CA, 5-75, 1990. 

B.W. Wilson, M. Hooper, E. Chow, R.J. Higgins, and J.B. Knaack, Antidotes and neuropathic potential of isofenphos. Bull. Environ. Contam Toxicol. 33 386, 1984. 

U.S. Environmental Protection Agency, Pesticide Environmental Fate On-Line Summary Isofenphos, Environmental Fate and Effects Division, Washington, DC, 1990. 

Isocarbamid amide, imidazolidinone Isofenphos phosphoro organic, phosphoro amido thioate... 

Phosphorus tribromide brodifacoum, difenacoum, fenpropidin, flocoumafen, pyriproxifen Phosphorus trichloride chloretoxyfos, disulfoton, EPN, ethephon, ethoprop, fonofos, fosamine ammonium, fosetyl aluminium, fosthiazate, glufosinate, glyphosate, isofenphos, merphos, propaphos, sulprofos, SSS-tributyl phosphorotrithioate, trichlorfon, trichloronat Phthalic acid pindone, tecloftalam... 

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