ARS PESTICIDE PROPERTIES last update May 1995 name:CHLORPYRIFOS CASRN: 2921-88-2 molecular formula: C9H11CL3NO3PS molecular weight : 350.62 physical state : S (L=liquid; G=gas; S=solid) reference: 9ACHB2 _________________________________________________________________________ Key to sources: (M)Manufacturer, (R)eview, (H)andbook, (E)xperiment, (C)alculated, (U)nknown, (P)EPA data, (W)auchope * denotes a selected value where multiple values of a property are listed. _________________________________________________________________________ -value- -medium- -temp- -pH- -source- -reference- Boiling point(deg C): - Melting point(deg C): 42 - 43.5 H 9ACHB2 Decomposition point(deg C): - Heat of vaporization(deg C): --RATE CONSTANTS-- Hydrolysis (per day): 0.009* 25 5 M 6DOWCH 0.0236* 25 7 M 6DOWCH 0.0440* 25 9 M 6DOWCH Photolysis (per day): Vapor pressure (mPa): 2.5* 25 H 9ACHB2 1983 ED. 12 35 H 9ACHB2 1983 ED. 2.3 20 R 9HRLCP 2.5(av.2.5,2.4,2.7) 25 M 6DOWCH Water solubility (ppm): -temp- -source- -reference- 1.18* (av. 1.20,1.39,0.94) 25 0.45 10 E JPFCD2 B20:625,1985 0.73 20 E JPFCD2 B20:625,1985 1.3 30 E JPFCD2 B20:625,1985 1.12 24 E JAFCAU 27:557,1979 Organic solubility (ppm): MISCIBLE ACETONE 25 H 9PMED8 MISCIBLE BENZENE 25 H 9PMED8 MISCIBLE CHLOROFORM 25 H 9PMED8 MISCIBLE METHANOL 25 H 9PMED8 Henrys law (Pa m3/mol): 0.743* 25 M 6DOWCH Octanol/water partitioning (log Kow): 5.0*(4.7-5.3) M 6DOWCH Acid dissociation (pKa): Soil sorption: soiltype temp. Kd Koc %om pH source reference 6070 E JEVQAA 16:422-428,1987 C 8BULEV 24:190-195,1980 1.36E04 R EESADV C 8SWAMD 1.4E04 R 8AOACA 5.3E03 C 8GLEAM 6085 E ETOCDK 8:339-357,1989 14800 E JPFCD2 22:55-69,1987 6100 R 8INSFO 1.35E04 R 8AGMAW 9930* Field Dissipation halflife(days): value test area pH %OM source reference 43(4-139)* 6-139 R JEENAI 78:412-418,1985 30 R JEENAI 78:412-418,1985 60 R RREVAH 85:139-147,1983 18-53 P 8EPAHO 63 R 8FULLE 60 R 8INSFO 90 H 9ACHB2 1983 ED. 63 E JEVQAA 16:422-428,1987 E SCSFAD 44:1-8,1985 12 C 8GLEAM 54 E ETOCDK 8:339-357,1989 9.5(6-12.9) SLTY CLY LM(IL) M 6DOWCH 25.5(6-58) SLT LM(NE,WA,BC,BELG) M 6DOWCH 45(12-77) CLY LM(ONT.) M 6DOWCH 23.5(6.8-78) SNDY LM(MI,IL,SOV,BELG,IND) M 6DOWCH 36.9(8.6-79.5) LM(CA,WA,IN,ITALY) M 6DOWCH 28(4-42) LMY SND(GA,BELG.) M 6DOWCH 22.3(6.8-80) SNDY LM(IL,BELG,SOV,IND) M 6DOWCH 24-45 SNDY CLY LM(SOV) M 6DOWCH 66.5(28-91) SNDY CLY(SOV) M 6DOWCH 59(27-91) CLY M 6DOWCH 72(39-120) MUCK(NY,ONT.) M 6DOWCH 22.8(6-58) SLT LM(WA,BC,BELG.) M 6DOWCH 7.6(1.3-14) SND(ONT.FL) M 6DOWCH Halflife in soil: Soiltype aerobic anaerobic source reference 30.5* M 6DOWCH Comments: SOIL SORPTION KOC=9930(6070-14800) AEROBIC = 30.5(12-102)