ARS PESTICIDE PROPERTIES last update May 1995


name:METHAM-SODIUM                             CASRN: 137-42-8

molecular formula: C2H4NNAS2
molecular weight : 129.18
physical state   : S
(L=liquid; G=gas; S=solid)
reference: 9ACHB2

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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):
       -

Decomposition point(deg C):
       -

Heat of vaporization(deg C):


--RATE CONSTANTS--
Hydrolysis (per day):
0.693*                           25     5        M     8ICIAG,03/01/90
0.092*                           25     7        M     8ICIAG,03/01/90
0.361*                           25     9        M     8ICIAG,03/01/90

Photolysis (per day):
10.4*                SOIL        25        7     M     8ICIAG,03/01/90

Vapor pressure (mPa):
0.0*                                             M     8ICIAG 03/01/90
21*(parent)                                      M     8ICIAG


Water solubility (ppm):       -temp-         -source-  -reference-
963000*                         20               M     8ICIAG 
7.22E04                         20               H     9HERBH
                                                 H     9ACHB2 1983 ED.
                                                 H     9FACHB 1990


Organic solubility (ppm):

Henrys law (Pa m3/mol):

Octanol/water partitioning (log Kow):
<1*                              25              M     8ICIAG 03/01/90

Acid dissociation (pKa):
17.6*                                            M     8ICIAG


Soil sorption:
soiltype        temp.   Kd      Koc      %om   pH     reference


Field Dissipation halflife(days):
value            test area        pH          source  reference
5-7                                             H     9HERBH
3                                               M     8ICIAG
4.5(3-7)*

Halflife in soil:
Soiltype               aerobic      anaerobic   source    reference

Comments:
VAPOR PRESSURE=rt:NONVOLATILE(SALT) REF. 9ACHB2 1983 ED. &
VAPOR PRESSURE 0.0 = AS SALT; 21 = PARENT