Registration Dossier

Administrative data

Endpoint:
other distribution data
Type of information:
calculation (if not (Q)SAR)
Remarks:
Migrated phrase: estimated by calculation
Adequacy of study:
supporting study
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
other: The result is sourced from secondary literature (company product literature). The original reference was not available for review and no further information is available.

Data source

Referenceopen allclose all

Reference Type:
study report
Title:
Unnamed
Year:
2000
Reference Type:
publication
Title:
Evaluating the environmental fate of a variety of types of chemicals using the EQC model
Author:
Mackay D, Di Guardo A, Paterson S, Cowan CE
Year:
1996
Bibliographic source:
Environ. Toxicol. Chem. 15:1627-1637
Title:
Unnamed
Year:
1985
Reference Type:
grey literature
Title:
Unnamed
Year:
1991
Report Date:
1991
Reference Type:
other: estimation software
Title:
Estimations Programs Interface (EPI) Suite™. (The EPI Suite™ and the individual models included within the software are owned and copyright protected by the U.S. Environmental Protection Agency.)
Author:
United States Environmental Protection Agency
Year:
2000

Materials and methods

Type of study:
other: Fugacity Model Level I, II and III

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
3-Glycidoxypropyltrimethoxysilane (TMSPGE, CAS No.
2530-83-8)

Upon contact with water or water vapor,
3-glycidoxypropyltrimethoxysilane generates methanol and the
corresponding silanol, 3-glycidoxypropylsilanetriol.
Depending upon concentration, 3-glycidoxypropylsilanetriol
will condense to form a highly cross-linked polymeric gel.

Results and discussion

Any other information on results incl. tables

Level-I Simulation. 
Environmental Compartment
                         Air        Water        Soil        Sediment 
Distribution (%)        0.0        100        0.0        0.0 

Level-II Simulation 
Environmental Compartment 
                         Air        Water        Soil        Sediment 
Distribution (%)        0.0        100        0.0        0.0 
Reaction losses(%)        0.0        99.1        0.0        0.0 
Advective losses(%)        0.0        0.9                0.0 
Overall residence time(h)  9.3 
Reaction residence time (h)  9.4 
Advective residence time (h)  1000 

Level-III Simulation 
A. Emission Rates (kg/h): Air = 1000; Soil = 0; Water = 0
Environmental Compartment
                         Air        Water        Soil        Sediment 
Distribution (%)        1.4        1.9        96.7        0.0 
Reaction losses(%)        11.2         14.2        73.6        0.0
Advective losses(%)        0.9        0.1                0.0 
Overall residence time(h)  69 
Reaction residence time (h)  70
Advective residence time (h)  6474 

B. Emission Rates (kg/h): Air = 0; Soil = 1000; Water = 0
Environmental Compartment        Air        Water        Soil        Sediment 
Distribution(%)        0.0        0.8        99.2        0.0
Reaction losses(%)        0.0        14.2        93.0        0.0
Advective losses(%)        0.0        0.1                0.0 
Overall residence time (h)  4 
Reaction residence time (h)  4 
Advective residence time (h)  5384 

C. Emission Rates (kg/h): Air = 0; Soil = 0; Water = 1000
 Environmental Compartment         
                        Air        Water        Soil        Sediment
Distribution (%)        0.0        100        0.0        0.0
Reaction losses (%)        0.0        99.1        0.0        0.0 
Advective losses (%)        0.0        0.9                0.0 
Overall residence time (h)  9.3 
Reaction residence time (h)  9.4 
Advective residence time (h)  1000 

D. Emission Rates (kg/h): Air = 1000; Soil = 1000; Water =
1000 
Environmental Compartment        
                        Air        Water        Soil        Sediment
Distribution (%)        0.6        6.9        92.5        0.0
Reaction losses (%)        3.7        40.1        55.5        0.0
Advective losses (%)        0.3        0.4                0.0 
Overall residence time (h)  55 
Reaction residence time (h)  55 
Advective residence time (h)  7930

The measured hydrolysis half-life for
3-glycidoxypropyltrimethoxysilane at pH 7.0 is 6.5 hours at
25 °C.  As such, 3-glycidoxypropyltrimethoxysilane will not
exist in the environment but will rapidly hydrolyze to
methanol and 3-glycidoxypropylsilanetriol.  The
environmental fate, transport, and distribution of
3-glycidoxypropylsilanetriol were evaluated to provide a
more realistic assessment of
3-glycidoxypropyltrimethoxysilane.  Results from the
simulation suggest that > 99% of the total steady-state mass
of 3-glycidoxypropylsilanetriol will reside in the water and
soil compartments, and will not be found in air or sediment.
 It is expected that 65-85% of the
3-glycidoxypropylsilanetriol produced by the steady-state
hydrolysis of 3-glycidoxypropyltrimethoxysilane will degrade
in about 20-35 days.


Air % (Fugacity Model Level I): 0
Water % (Fugacity Model Level I): 100
Soil % (Fugacity Model Level I): 0
Biota % (Fugacity Model Level II/III): 0
Soil % (Fugacity Model Level II/III): 0

Applicant's summary and conclusion

Executive summary:

Results from the multimedia model simulations indicate that 3-glycidoxypropyltrimethoxysilane will not persist in the environment, but will degrade to methanol and 3-glycidoxypropylsilanetriol. If released directly to air, about 11% of the steady-state emission is expected to degrade in air, 74% expected to partition to and degrade in soil, and 14% expected to partition to and degrade in water. When released to soil 93% of the steady-state emission is expected to degrade in soil and 7% expected to partition to and degrade in water. When released directly to water, essentially 100% of the steady-state emission will degrade in water. Advection from the local environment is expected to be insignificant (less than or equal to 1% of the steady-state emission) for all emission scenarios. Global persistence of 3-glycidoxypropyltrimethoxysilane in the model system was about 3 days when released directly to air or soil, and about 0.5 days when released to water. If released simultaneously to all three compartments (i.e., air, water,

and soil), essentially 100% of the steady-state emission degrades in about 2 days. Based on Level-III modeling, it is expected that > 99% of the total steady-state mass of 3-glycidoxypropyl-trimethoxysilane will reside in the water and soil compartments and will not be found in air or

sediment.