Chlorpyrifos solubility

Chemicals Used. Chemicals used in this study were technical grade products or better, dissolved in xylene with 5% emulsifying agent. The chemicals used included an oil soluble red dye, Dino-seb (2-sec-butyl-4,6 dinitrophenol), pentachlorophenol (PCP), Isopropyl N-(3-chlorophenyl) carbamate (CIPC or Chlorpropham), Iso-octyl 2,4,5- trichlorophenoxy acetate (2,4,5-T), chlorpyrifos (0, 0-diethyl 0-(3,4,6-trichloro 2-pyridyl) - phosphorothioate), and Ronnel (0-dimethyl 0-2, 4,5-trichlorophenyl) phosphorothioate) for application as a spray. The emulsifiable concentrate was diluted in water comparable to 50 gallons of spray to contain the following amounts respectively 2 lbs. for chloropryifos 4 lbs. for 2,4,5-T 3 lbs. CIPC and 2 lbs. for PCP. 

Example 2b) Estimate Koc and Kd for chlorpyrifos in a soil containing 4% organic carbon using the aqueous solubility value provided in Table 8.7 (log S = -6.07). 

Neurotoxic chemicals and motor neuropathy Chlorpyrifos, dichlorvos (DDVP), EPN, n-hexane, 2-hexanone, lead, lead chromate, lead II thiocyanate, leptophos, methamidophos, mipafox, omethoate, parathion, trichlor-fon, trichloronate, triorthocresyl phosphate Neurotoxic chemicals and sensorimotor neuropathy acrylamide, allyl chloride, arsenic and compounds, arsenic trichloride, calcium arsenate, carbon disulfide, dichloroacetylene, ethylene oxide, gallium arsenide, lead arsenate, mercuric chloride, mercuric nitrate, mercurous nitrate, mercury, nitrous oxide, phenyl arsine oxide, thallium and soluble compounds, thallous nitrate... 

Somewhat water-soluble pesticides such as acid herbicides will be washed from foliar surfaces and into subsurface soils by rainfall. For example, dislodge-able turf residues of 2,4-D after a 2.54-cm rainfall have been reported to be only 1-5% of those found at 4-8 h after application (Nishioka et al., 1996 USEPA, 1997c). However, dew or rain on aged turf residues may increase their dislodgeability (Nishioka et al, 1996). OP insecticides are semivolatile and will vaporize from surfaces after applications. Chlorpyrifos vaporizes rapidly from lawns if applied in aqueous formulations. Diazinon, which is used on lawns as well as indoors, dissipates even more rapidly. However, the persistence of OP... 

A well-documented example of this approach is a study of the fate of the pesticide, chlorpyrifos, in a pond in Missouri (87 reviewed by Branson, 75). The conceptual model includes rate constants for each of the transport and transformation processes affecting the final concentrations of chlorpyrifos in the water, the sediment, and the fish. The rate constant for evaporation from water is estimated from data on vapor pressure, solubility, and molecular weight (for techniques, see 33, 68, 71). The remaining rate constants for the pond model are derived from laboratory studies. When validated by sampling in a pond, the predicted and environmentally measured concentrations of chlorpyrifos showed close agreement (75). 

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