A mixture of RR and RS isomers of: (2-(2-methoxy-1-methyl)ethoxy)-1-methylethyl acetate; (2-(2-methoxy-2-methyl)ethoxy)-1-methylethyl acetate; (2-(2-methoxy-2-methyl)ethoxy)-2-methylethyl acetate; (2-(2-methoxy-1-methyl)ethoxy)-2-methylethyl acetate

Distribution modelling

Administrative data

Endpoint:

distribution modelling

Type of information:

calculation (if not (Q)SAR)

Remarks:

Migrated phrase: estimated by calculation

Adequacy of study:

key study

Study period:

2009

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

There are no guidelines on how to conduct this type of modelling but the methods described are well accepted scientifically. The model used for predicting transport between environmental compartments was Level III fugacity model (method Mackay Level III).

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

Report date:

2009

Materials and methods

Model:

calculation according to Mackay, Level III

Release year:

2 004

Test material

Test material information

Constituent 1

Study design

Environmental properties:

INPUT PARAMETERS

Chemical Type: 1
Molecular Mass (g/mol): 190.2388
Data Temperature (Degrees Celsius): 20
Log Kow: 0.61
Water Solubility (g/m3): 183000
Water Solubility (mol/m3): 962
Henry's Law Constant (Pa.m3/mol): 0.0108
Vapour Pressure (Pa): 10.4
Melting Point (Degrees Celsius): -25.2

Results and discussion

Percent distribution in media

Air (%):

0.1

Water (%):

99.9

Soil (%):

0.1

Sediment (%):

0.1

Other distribution results:

Reported distribution based on emission scenario for 1000 kg/hr to water. This is the most probable emission route based on physical properties and use patterns.

Any other information on results incl. tables

Level III: Predicted distribution of DPMA among air, water, soil, and sediments

Emission Scenario	Percentage and amount distributed to				Residence Time (days) [without advection in brackets]
	Air	Water	Soil	Sediment
1,000 kg/hr to Air	0.7% 5291 kg	56.1% 4.22 x 10^5 kg	43.2% 3.25 x 10^5kg	<0.1% 174 kg	70 [ 31]
1,000 kg/hr to Water	<0.1% 5 kg	99.9% 8.38 x 10^5 kg	<0.1% 302 kg	<0.1 % 347 kg	35 [216]
1,000 kg/hr to Soil	<0.1% 613 kg	55.2% 7.45 x 10^5 kg	44.7% 6.03 x 10^5kg	<0.1% 308 kg	56 [234]
1,000 kg/hr simultaneously to Air, Water, and Soil	0.2% 5910 kg	68.2% 2.00 x 10^6kg	31.6% 9.28 x 10^5kg	<0.1% 829 kg	41 [144]

Highlighted scenario indicates most probable emission route, based on physical properties and use patterns

Applicant's summary and conclusion

Executive summary:

The environmental distribution and transport of dipropylene glycol methyl ether acetate (DPMA) between environmental compartments (air, water, soil, and sediments) was predicted using a Level III fugacity model. Input values required by the model include molecular weight, melting point, water solubility, vapor pressure, and octanol/water partition coefficient.  In addition to these parameters, the model requires input of measured or estimated half-lives for reaction in air, water, soil, and sediments. The model incorporates transport rates into and between environmental compartments, and allows for losses of the compound due to advection or degradation processes. 

 

This substance has high water solubility, a very low vapor pressure, and low log K_ow. The substance therefore has a low potential for adsorption to soil or sediments, and a low potential to volatilize from water or soil to the atmosphere. If released to air, the substance will react with hydroxyl radicals. If released directly to water, the most probable emission route based on physical properties and use patterns, most of the substance will remain in the water compartment and is expected to be biodegraded. If released to soil, the substance is expected to be biodegraded. These modeling calculations, and associated input emission rates and output environmental concentrations, are intended solely to illustrate potential for distribution and transport of the substance among environment compartments. These results are not intended for use in derivation of predicted environmental concentrations (PEC) for specific compartments and/or use patterns.