Registration Dossier

Administrative data

distribution modelling
Type of information:
Adequacy of study:
key study
Study period:
10 April 2020
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification
Justification for type of information:
Estimation Programs Interface (EPI) Suite for Microsoft Windows, v4.11 (US EPA, 2012)

2. MODEL (incl. version number)


See attached QMRF.

See attached QPRF.

- The model is scientifically valid (see attached QMRF).
- The model predicts partitioning of chemicals among air, soil, sediment, and water under steady state conditions for a default model "environment".
(mass amounts for the 4 compartments, the corresponding half-lives and the overall persistence, see also attached QPRF).
- See attached QPRF for reliability assessment.

Data source

Reference Type:
other: in silico model
Level III fugacity model (EpiSuite v4.1)
Bibliographic source:
The Canadian Environmental Modeling Centre (CEMC)

Materials and methods

calculation according to Mackay, Level III
Calculation programme:
LEV3EPI™ implemented in EpiSuite v4.1
Level III Fugacity Model of EPI Suite v4.11 with Single Level III Output option (adaptation of Mackay's EQC model for EPI Suite); Single Level III Output runs the Fugacity Model once using the emission rates of air water and soil each at 1000 kg/h (model default values). AOP conditions: 12-h day, 1.5E06 OH/cm³
Release year:
1 996
other: air - water - soil - sediment

Test material

Constituent 1
Chemical structure
Reference substance name:
EC Number:
EC Name:
Cas Number:
Molecular formula:
Specific details on test material used for the study:

Study design

Test substance input data:
- Molar mass: 85.11
- Data temperature:
- Water solubility: 6.797E+005 mg/L
- Vapour pressure: 0.013 mm Hg
- log Pow: -0.71
- Henry's LC: 1.06E-9 atm-m3/mole (Henry database)
- Melting point: 25°C
- Reaction half-life estimates for
- Air: AOPWIN estimate
- Water: BIOWIN (Ultimate) estimate
- Soil: BIOWIN (Ultimate) estimate
- Sediment: BIOWIN (Ultimate) estimate
Environmental properties:
see "Any other information on materials and methods incl. tables"

Results and discussion

Percent distribution in media

Air (%):
Water (%):
Soil (%):
Sediment (%):

Any other information on results incl. tables

Level III Fugacity Model (Full-Output):


Chem Name  :

Molecular Wt: 85.11

Henry's LC : 1.06e-009 atm-m3/mole (Henry database)

Vapor Press : 0.013 mm Hg (user-entered)

Log Kow    : -0.71 (user-entered)

Soil Koc   : 7.38 (KOCWIN MCI method)


Mass Amount            Half-Life          Emissions

                      (percent)               (hr)               (kg/hr)

Air                                    0.0228               21.5                    1000

Water                               32.2                   360                     1000

Soil                                   67.7                   720                     1000

Sediment                         0.0689              3.24e+003           0


Fugacity    Reaction   Advection   Reaction    Advection

(atm)       (kg/hr)      (kg/hr)    (percent)   (percent)

Air       1.22e-012    13.7        4.26        0.458      0.142

Water     3.75e-014    1.16e+003   602         38.7        20.1

Soil          1.84e-012    1.22e+003   0           40.6        0

Sediment  3.41e-014    0.276       0.0258      0.0092      0.00086


Persistence Time: 624 hr

Reaction Time:   782 hr

Advection Time:  3.08e+003 hr

Percent Reacted: 79.8

Percent Advected: 20.2


Half-Lives (hr), (based upon Biowin (Ultimate) and Aopwin):

Air:     21.51

Water:   360

Soil:    720

Sediment: 3240

Biowin estimate: 2.957 (weeks)


Advection Times (hr):

Air:     100

Water:   1000

Sediment: 5e+004

Applicant's summary and conclusion

Over time, the substance will preferentially distribute into the compartments soil (68%) and water (32%).
Executive summary:

Distribution modelling for 2 -pyrollidone was performed using the Level III fugacity model of the scientifically accepted computer program EPIWIN v4.1 by US-EPA. The executable file is called LEVEL3NT.EXE.The software is no stand-alone version and it contains a direct adaption of the Level III fugacity model developed by Mackay (1991) and Mackay et al. (1996). Level III modelling assumes a steady-state, but no common equilibrium conditions between the different environmental compartments. Four main compartments are concerned: air, water, sediment and soil. Between these compartments, mass transport is modeled via volatilization, diffusion, deposition and runoff. A fixed temperature of 25 °C is assumed. The substance properties vapour pressure, partition coefficient, water solubility and melting point were entered manually.

In general, disappearance of a chemical occurs via two processes: reaction and advection. The abiotic or biotic degradation belongs to reaction, whereas the removal from a compartment through losses other than degradation is called advection. The rate of advection is determined by a specific flow rate, which may be specified by the user. Furthermore, the user can specify emission rates; otherwise the default emission rate is equal amounts to air, water and soil. For the sediment compartment, no direct emissions are considered. If half-lives in the different compartments are known, the values should be entered manually. Otherwise, EPIWIN software BIOWIN (Biowin 3 – Ultimate Biodegradation Timeframe) and AOPWIN are used to make these estimations by default. If a chemical is susceptible to abiotic hydrolysis, HYDROWIN may be able to provide the half-life.If a combination of hydrolysis, photolysis and biodegradation is likely for the compound, the half-lives shall be converted to rate constants and added together. The resulting overall half-life should be entered into the modelling.The output of Biowin 3 cannot be used directly by the Level III mass balance model. The mean value is converted to a half-life using a set of conversion factors, which consider that 6 half-lives constitute complete degradation with first-order kinetics.

Ultimate biodegradation is generally slower under anaerobic conditions than under aerobic conditions. The program concerns aerobic conditions; only for sediment an anaerobic environment is assumed. The rate of ultimate degradation in sediment is on average one-ninth (1/9) of that in the water column. A further adjustment is taken into account: In general, the biodegradation rate in soil is, on average, one-half (1/2) that in water. Therefore, a half-life in soil twice that estimated for water is assigned.The default environmental emission rates are 1000 kg/h to air, water and soil (sediment: 0 kg/h), which may be altered manually.The advection lifetimes of the substance in air, water and sediment compartments are set to the default values of 100, 1000 and 50000 hours, respectively. These lifetimes are used to determine the advective flow rate (m³/h). If no advection to any compartment is expected, the lifetime should be set to some arbitrarily large value (such as 1E20); this effectively changes the advective flow rate to zero. A soil Koc value is also required for the fugacity model. By default, the connectivity-based adsorption coefficient is used (MCI result by KOCWIN).

For this calculation the default of 1.5E+6 OH radicals/cm³ and a 12 -hrs day was used.

Concerning 2 -pyrrolidone, for the 4 compartments, i.e. air, water, soil and sediment, the following mass amounts are predicted for the representative structure: 0.0228 %, 32.2 %, 67.7 % and 0.0689 %, respectively. The corresponding half-lives in the different compartments are predicted as: 21.5 h, 360 h (ca. 15 days), 720 h (ca. 1 month) and 3240 h (ca. 135 days), respectively. The overall persistence time gives a measure of how long the chemical remains in the model environment and is estimated as 624 h (ca. 26 days) for the test substance.