ARS PESTICIDE PROPERTIES last update May 1995


name:TRIBUFOS                                  CASRN: 78-48-8

molecular formula: C12H27OPS3
molecular weight : 314.52
physical state   : L
(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):
150    -             0.3mmHg                      H    9ACHB2

Melting point(deg C):
       -

Decomposition point(deg C):
       -

Heat of vaporization(deg C):

--RATE CONSTANTS--

Hydrolysis (per day):
STABLE*                        25       5,7           M   6MILES
0.0056*                        25       9             M   6MILES

Photolysis (per day):
<0.023*              SOIL      9-42 OD                M   6MILES
0.00234*             WATER     25                     M   6MILES

Vapor pressure (mPa):
0.213*                         20                     M   6MILES


Water solubility (ppm):      -temp-              -source- -reference-
23*                            20                     M   6MILES

Organic solubility (ppm):

Henrys law (Pa m3/mol):
0.029*                         20                     M   6MILES

Octanol/water partitioning (log Kow):
5.52*                          20                     M   6MILES

Acid dissociation (pKa):


Soil sorption:
soiltype      temp.   Kd     Koc    %om   pH   source  reference
SAND          25      66.8   12684  1.0   4.3     M    6MILES
SANDY LOAM    25      60.6   10465  1.1   6.6     M    6MILES
SILT LOAM     25      74.3   4870   2.9   5.9     M    6MILES
CLAY LOAM     25      106    9115   2.2   6.4     M    6MILES
                             7700*

Field Dissipation halflife(days):
value         test area          pH    %OM     source  reference
19.3        CA(CHAULAR)LMY SND   7.3              M    6MILES
47-7        CA(FRESNO)LMY SND    7.8              M    6MILES
32*

Halflife in soil:
Soiltype            aerobic      anaerobic     source  reference
SANDY LOAM          745*         701*             M    6MILES      


Comments:
SOIL SORPTION KOC VALUE=7700(4870-12684)