United States
Environmental Protection
Agency
r1
Office of Water
Regulations and Standards (WH553)
Washington DC 20460
1961
Final Draft Report
Water
EPA Prediction of
Chemical Partitioning
in the Environment
An Assessment of
Two Screening Models
V
rfhis document nas not been peer and
'administratively reviewed within EPA
'and is for i
distril
'I
Signature and Date
U.S. Environmental Preterit ion i.£:}>iv?
.CISSAiT/, PMS13, Roocaj 2'iW
4•:.'? ;.; su*»ot7 s.w.
gj'ashj.ngtcn, DC £0490 S'CC? 460
8550308

DISCLAIMER
This is a contractor's final draft report, which has been reviewed by the Monitoring and Data
Support Division, U.S. EPA. The contents do not necessarily reflect the views and policies of the
U.S. Environmental Protection Agency, nor does mention of trade names or commercial products
constitute endorsement or recommendation for use.

PREDICTION OF CHEMICAL PARTITIONING IN THE ENVIRONMENT
An Assessment of Two Screening Models
FINAL DRAFT REPORT
. by
Warren J. Lyraan
Arthur D. Little, Inc.
for the
U.S. Environmental Protection Agency
Office of Water Regulations and Standards
•Monitoring and Data Support Division
Washington, D.C. 20460
Task Manager: Charles Delos
Project Officer: Michael Slimak
Contract No. 68015949, Task 2
May 1981
U.S. Environmental Protection Agency
LIBRARY, FM213, Rooom 2404
401 M Street, S.W.
Washington, DG 2Q46Q STOP 460
2027550308 655^0308

1 FOREWORD
• . * '; !
Effective regulatory action for toxicchemicals requires an under
. .• • C
standing of the human and environmental risks associated with the manu
facture, use, and disposal of the chemical. Determining the origins of
risks requires an understanding of the behavior the chemical in tra
versing the environment. Such behavior includes the chemical's tendency
to undergo biological or chemical degradation, and its tendency to par
tition between phases.
The intent of this work was to explore facile, methods for predicting
the partitioning between air; water, soil, sediment, and biota, under
"*'•''
both equilibrium and steady state (nonequilibriura) conditions. As per
formed for the 114 organic compounds on the EPA water programs list of
129 priority :pollutants, partitioning estimates can suggest the environ
mental mediaimost subject to contamination by each compound, and thereby
assist in guiding investigative and ^analytical efforts into productive
directions.
Charles G. Delos, Task Manager
.  Water Quality Analysis Branch
Monitoring and Data Support Division (WH553)
; .Office of Water Regulations and Standards
ii

ABSTRACT
This report provides an assessment of two screening models that
may be used to predict environmental partitioning, and the importance of
certain degradation and transport pathways, for organic chemicals. These
models may play an important role in environmental fate assessments, in
the initial steps of risk assessments for new or existing chemicals,
and in the planning of laboratory and field tests with such chemicals.
The models studies were: (1) a fugacitybased model by Donald Mackay
which provides different levels of sophistication for a variety of sit
uations; and (2) a partitioning model by W. Brock Neely based on data
from a model ecosystem. Both models are easy to use, require a minimum
of input data, and are capable of solution with a hand calculator. Model
outputs for both include predictions of the precent of the chemical in
the air, water and soil compartments. Other outputs may also be. obtained,
the Mackay model being much more flexible in this regard.
s
This report describes each model, provides detailed instructions for
their use, shows the results of sample calculations for several chemicals,
and provides a comparison of monitoring data and predicted values for a
few cases.
iii

TABLE OF CONTENTS
Page
Foreword , 11
Abstract ; ill
List of Tables yi
List of Figures viii
I. INTRODUCTION • • 11
A. Background  . 11
B. .Mackay's Fugacity Approach • 11
/
C. Neely's Approach • »v 14
D. Study Objectives * 15
E. Report Contents 15
II. CONCLUSIONS . IIl
III. LEVEL 1 MACKAY CALCULATIONS IIIl
A. Basic Assumptions , IIIl
. .' i
B. Description of the Model Environment III2
1) Accessible Volumes III4
2) "Concentration" of Suspended and III4
Bottom Sediments and Soil,
3) Organic Carbon Content of Sediments and'. III5
Soils
" h. "v
4) "Concentration" of Biota in Water III5
P • T.
5) Temperature III5
•" f
C. ChemicalSpecific Parameters Required III6
D. Level I Equations III9
StepByStep Instructions 11115
iv

TABLE OF CONTENTS (cont.)
Page
IV. CALCULATIONS USING NEELY'S APPROACH IV1
A. Basis for Approach IV1
B. Sample Calculations IV6
V. LEVEL.II MACKAY CALCULATIONS Vl
A. Basic Assumptions/Model Output Vl
B. Description of the Model Environment' V2
C. ChemicalSpecific Parameters Required V2
D. Level II Equations V7
StepByStep Instructions V8
E. Level II Calculations, With Advection, For Vll
One Chemical
F. Level II Calculations for Test Set (No Advection) V15
G. Comparison of Predicted Concentrations with V26
Monitoring Data
VI. LEVEL III MACKAY CALCULATIONS VI1
A. Basic Assumptions/Model Output VI1
B. Description of the Model Environment VI4
• * *•*•«
C. ChemicalSpecific Parameters Required VI4
D. Level III Equations VI5
StepByStep Instructions VI6
E. Level III Sample Calculation '• VI7
VII. LIST OF SYMBOLS USED VII1
VIII. REFERENCES VIII1
.v

LIST OF TABLES
Table
No. Page
1 Summary Information on the Models Studied 12
2 Estimates of S, P and H for Selected Chemicals III7
vp
3 ChemicalSpecific Input Parameters for Level I 11117
Approach, and Calculated Fugacity
4 Mass of Chemical in Each Subcompartment Using 11125
Level I Approach
5 Calculated Concentrations of Chemicals in Each 11133
Subcorapartment Using Level I Approach
6 Description of the Model Ecosystem Used by Neely IV2
7 Properties of a Series of Chemicals Tested in the IV3
Simulated Aquatic Ecosystem
8 Distribution of the Chemicals Shown in Table 7 in IV4
the Various Compartments of the Simulated Ecosystem
9 Chemicals and Input Data Used with Neely*s Equations IV7
10 Results of Calculations Using the Neely Approach IV9
11 FirstOrder Rate Constants Used in Level II V4
Calculations
12 Scheme for Assignment of Rate Constants for Level II V6
Calculations
13 Summary of CompartmentSpecific Equations and . V10
Parameters for Level II Calculations
14 FirstOrder Rate Constants for Tetrachloroethylene V12
15 Level II Calculations for Tetrachloroethylene  V13
Intermediate Parameters
16 Final Results of Level II Calculations for V14
Tetrachloroethylene
17 Results of Level II Calculations for Test Set V16
18 Measured vs Environmental Concentrations for V28
Selected Chemicals
vi

LIST OF TABLES, (cent.)
Table
No. Page
19 Sensitivity of Level III Outputs' to D and I • VI12
Values. Test Calculations for Trichloroethylene
vii

LIST OF FIGURES
Figure
Page.
Schematic of Environmental Compartment Selected,, < III3
for Estimation of Equilibrium Partitioning of
Organic Chemicals
Estimated Residence Time in Compartment from V22
Level II Calculations (No Advection)
Estimated Concentration in Water Compartment from V23
Level II Calcualtions (No Advection)
Estimated Concentration in Air Compartment from V24
Level II Calculations (No Advection)
Estimated Concentration in Sediment Compartment V25
from Level II Calculations (No Advection)
Plot of Distribution Predicted by Level II V27
Calculations. Percent in Air, Water or Soil
and Sediment Compartment
viii

I. INTRODUCTION
A. Background
As an Initial .step in hazard or risk assessments for toxic chemicals,
and in the planning of laboratory and field tests with such chemicals,
it is important to understand the likely transport and fate of the chemi
cal. Which environmental compartment (air, water, soils, sediments,
biota) will be most affected? Which transport and degradation pathways
(photolysis, hydrolysis, volatilization, etc.) will be most important?
Rough guesses can sometimes be made by simple inspection of the chemical's
properties and reaction rate data  if such are available  or by the use
of mathematical models which seek to yield defensible and quantitative
estimates. Unfortunately, realistic chemical fate models usually require
extensive input information (not always available) and a computer for' '..
solving the lengthly calculations.
A simple, initial estimate of environmental partitioning, fate and
transport is thus desired; one involving an approach with minimal input
data requirements and capable of solution with a hand calculator. Such
approaches have been proposed by Mackay (1979) and Neely (1978a, b),
amongst others. It was the primary objective of this study to investigate
these two approaches and to determine their applicability to the general
need described above. Table 1 provides summary information on the models
studied.
8. Mackay* s Fugacity Approach
Fugacity* is a thermodynamic property of a chemical. It is related
to chemical potential but is easier to use in practical applications.
Fugacity has units of pressure (e.g., atm.) and is sometimes thought of
as a "corrected pressure" or "escaping tendency" of a chemical from a
phase. Three further points (Mackay, op. cit.'):
* From the Latin ^uga, meaning flight or escape.
11

I
ro
TABLE 1
Summary Information on the Models Studied
PROCESSES
MODELED

•
CHEMICAL
SPECIFIC
INPUTS
REQUIRED3
OUTPUTS3
Neely's
Method
• Partitioning in
model ecosystem
.
H,. S
(4 compartment)
% in Air, Water
and Soil; half
life for clearance
from fish
Mackay's Model
Level I Level II
.• Equilibrium • Steadystate
partitioning partitioning
. • Degradation
• Flux of chemical
into model envi
ronment
• Advection out of
" model environment

M, MW, H, K , MW, H, K I, k
BCF ' K
,, ^ xb (4 compartments)
(6 compartments) v F / .
H . , C . M . , • C . , R^ , T ,
M(=EM;)
Level III
• Steadystate par
• titioning
• Degradation
• Flux of chemical
into any subcom
partment
• Advection out of
model environment
• Intercompartmental
transfers
MB, B, Koc> Ilf k^,
"«
(4 compartments)
M,. , C^ , R.^ , T ,
M(=EM±)
a. Section VII provides definitions for the symbols used in this report. For many organic chemicals
all of the input chemical properties required (S,H,K , k , D) can be estimated. .
oc x
b. Additional compartments may be modeled if desired. Additional parameters will be required in some
cases. '•.'

1) Fugacity is linearly proportional to concentration (at least
at the low concentrations of anthropogenic chemicals usually
found in the environment).
2) For two phases in contact, the tendency is for a chemical to
move out of the phase where it has the higher fugacity value
into the other phase.
3) When the chemical's fugacity in the two phases is the same, the
distribution of the chemical between the two phases is the
equilibrium distribution.
As is always the case with thermodynamic considerations, an approach
that only considers fugacity cannot tell us how quickly a chemical is (or
should be) approaching equilibrium between two phases, just in which direc
tion equilibrium lies. There are two general areas in which the approach
can contribute to a better understanding of the fate and transport of
toxic substances. First, if concentration data are available for a pollu
tant in several phases, these concentration data can be converted to
fugacitles and the fugacity levels compared. Second, the approach may be
used to predict environmental levels (at equilibrium) for a new compound
which is being marketed for the first time, or for an old chemical for
which there are significant data gaps in the ambient monitoring file.
A fourtiered approach is suggested by Mackay. We report here on
investigations of the first three levels of calculations.
Level I considers the equilibrium partitioning of an organic chemi
cal in a static model environment with specified subcompartments (e.g.,
air, water, soil, biota). No degradation or transport is allowed. The
calculations require that the subcompartments be roughly, described
(volumes, sediment and biota "concentrations," temperature, etc.) and that
the amount of the chemical in the model environment be specified. A
relatively small number of chemicalspecific parameters are also required.
13

These parameters are used to calculate a "fugacity capacity constant,"
Z, which is related to fugacity, f, and compartment concentration, C, by
the formula C » Zf. .
Level II allows a steadystate input of the chemical into the model
environment, advection out of the model environment, and degradation by
any process for which a firstorder degradation rate constant can be
obtained. Compartmental concentrations, removal rates and an overall
lifetime of the chemical (in the model environment) are calculated, again
using the basic fugacity approach.'
Level III improves upon the previous levels by allowing a steady
state input ;of the chemical into any subcompartment and noninstantan
eous intercompartment transfers (e.g., volatilization). All other fea
 • ' u •••.="
tures of the Level I and II calculations are kept and the same outputs
* y
calculated.
Level IV (not investigated in this study) is concerned with non
steadystate distributions in the environment. The calculations would
generally require a computer.
C. Neely's' Approach
The Neely work (Neely, 1978 a, b) is based upon laboratory data from
a model environment into which small amounts of various chemicals were
placed. After a suitable waiting period, the concentration in each major
compartment  air, water, soil  was measured. The halflife for clearant
from fish is also obtained from laboratory data.
Using such data for ten chemicals exhibiting a wide range of
solubilities and vapor pressures, four regression equations were derived
allowing predictions of partitioning and fish clearance rates for other
chemicals. These predictions are intended to be used in a screening
process and are not expected to provide defensible quantitative estimates
of chemical partitioning.
14

t.D.,, , Study Objectives, ,..,.,: ^:, >^ a^iv.1*
The primary objective of the study was.?to,.investigate .the Neely and
Mackay models to assess the ease of use and usefulness for estimating
the partitioning, transport and fate of organic chemicals in the environ
ment. A secondary objective was to use the Mackay Level I approach to
predict the partitioning of most  if not all  of the organic priority
pollutants. Other secondary objectives were to compare the Neely and
Level I Mackay approaches, to investigate the sensitivity of the model to
various input parameters, and to compare model outputs (predicted environ
mental concentrations) with monitoring data for a selected group of chemi
cals .
E. Report Contents
Section II  Provides conclusions drawn from this study.
Section III  Describes Mackay's Level I approach. All necessary
equations and stepbystep instructions for their use are provided.
Calculations are shown for all organic priority pollutants.
Section IV  Describes Neely1s approach. f All necessary equations
are given. Calculations are shown for 20 organic chemicals and the
results compared with the Level I (Mackay) predictions.
Section V  Describes Mackay's Level II approach. All necessary
equations and stepbystep instructions for their use are provided.
Calculations are shown for a test set of 24 chemicals. Comparisons
with monitoring data are made for 8 chemicals.
Section VI  Describes Mackay's Level III approach. All necessary
equations and stepbystep instructions for their use are provided.
Sample calcualtions, including a sensitivity analysis for two
parameters, are provided for one chemical.

Section VII  Provides a listing of the symbols used in this report.
Section VIII  References.
16

II. CONCLUSIONS
1. AH of the models studied are easy to use, require a minimum of in
put data (much of them estimable), and are capable of solution with a
hand calculator. All are essentially limited to'use with singlecompon
ent organic chemicals, i.e., they cannot be used for complex mixtures,
solutions, salts, polymers or inorganic compounds.
2. Both the Mackay (Level I) and the Neely models fulfill the need for
a simple, easy to use environmental partitioning model. The Neely
approach is somewhat easier to use and requires fewer input parameters.
It can, however, yield mathematically incorrect results (e.g., percents
<0 or >100 for partitioning) which, while unsettling, can be overlooked
if they are used only for screening purposes. The Mackay Level I model
is a more rigorous approach with a significant amount of flexibility •"
with regard to the type of environment to be considered. The subcompart
ments and their accessible volumes must be described, if concentrations
in specific compartments'are to be calculated. Accessible volumes of the
subcompartments do not need to be defined if only concentration ratios
(e.g., concentration in air/concentration in water) are to be calculated.
3. If the analyst is only interested in calculating concentration
ratios between pairs of subcompartments or the percent (mass) in any =
subcompartment, the Level I Mackay calculation should be used. (The
Level I and Level II methods give identical results for these calcula
tions.) Accessible volumes in eachsubcompartment do not have to be speci
fied for the former calculation (concentration ratios) but do for the
latter (percent distribution of mass).
4. Both the Level I and Level II Mackay calculations give results
for an environment which has attained equilibrium partitioning. The
nature of this partitioning is most simply calculated.with the Level I
model; the relative importance of various degradation processes can
only be assessed with the Level II (or III) model. The Level II model
IIl

thus requires that degradation rate constants (e.g., for hydrolysis, bio
degradation, photolysis) be known or estimated.
5. The Level III Mackay model allows the analyst to obtain the ab
solute (or relative) concentrations in various subcompartments under
nonequilibrium conditions. For these calculations it is necessary
for the important intercompartmental transfer processes to be described
in a set mathematical format. At present, only volatilization from
water can be included in a rigorous manner; transfer coefficients for
other intercompartmental transfer processes must be guessed. This is '
considered to be a significant limitation of the Level III approach.
Just how closely the Level III outputs resemble those from Levels 1 and
II appears to depend primarily on how the input load is distributed
between the media (air, land, water) and on the selected intercompart
mental transfer coefficients. The results of Level I, II and III cal
culations for one chemical (trichloroethylene) are compared on page
VI12; the output shown there indicates the range of answers that may
be obtained with various Level III inputs.
6 These models make no attempt to describe the fate and transport of a
chemical in a welldefined, realistic environment. Both essentially con
sider a generalized box environment containing air, water, soil and biota
(plus other compartments, if desired, in the Mackay model) and equilibrium
or steadystate partitioning. The models should primarily be considered
as screening models to determine what future studies are likely to be
important for a particular chemical.
7. In spite of the limitations mentioned in (6) above, there will
always be a temptation to use some of these models as predictive tools
for specific locations. The Mackay Level II and III models incorporate
a sufficient degree of realism—at least with regard to chemical degra
dation and transport—that the calculated environmental concentrations
might be taken as realistic predictions in some cases.
 II2

8. If the Mackay model is to be used as a predictive model for a
specific location, then some special care must be taken in the descrip
tion of the model environment so that it approximates the actual environ
ment. This poses some problems since .the Mackay model does not, as cur
rently formulated, allow for different portions of a subcompartment to
contain different concentrations of a chemical; all portions of that sub
compartment are taken to be equally accessible to the partitioning chemi
cal. A related problem is the size or accessible volume of a subcorapart
ment in relation to the lifetime or mobility of the pollutant in that
subcompartment. It is unrealistic, for example, to stipulate a 10 km
height for the air compartment for a chemical which is released at ground
level and has an atmospheric lifetime of only a few hours (e.g.,.due to
rapid photolysis) . For such a chemical a 1 km height would be moire
appropriate.
A comparison of calculated concentrations (Level II) with monitoring
data is given in Section VG for eight chemicals. The comparison showed
that wide discrepancies may frequently be seen, especially for surface
water concentrations. These discrepancies may be due to the combined
effects of: (1) a bias towards more polluted media in monitoring pro
grams; (2) problems in obtaining meaningful averages from reported data;
and (3) a bias in the sample calculations of this report towards less
polluted areas. None of these possible reasons reflects any fundamental
flaw in the model used.
II3

III. LEVEL I MACKAY CALCULATIONS
A. Basic Assumptions
The basic assumptions of the Level I calculations are as follows:
. • All of the environmental subcompartments (air, water, soil,
etc.) are at equilibrium, and there is no net flux of the sub
compartment material (air, water,, soil, etc.) into or out of
any subcomparttnent or the compartment as a whole.
• The chemical is at equilibrium in the.environmental compart
ment, and there is no net transport of the chemical between any
subcompartments, and no net flux into or out of the compartment
as a whole.
• No chemical or biological degradation of the chemical takes
place.
In addition to the above, there are a number of assumptions (or
estimates of various parameters) that are associated with a particular
set of calculations. One such set of assumptions is related to the size,
accessible volumes, and nature of.the various subcompartments selected
for study. Details on the compartment—related parameters selected for
use in the Level I calculations are given in the following subsection.
The specific numbers used were selected somewhat subjectively and are
not to be considered representative of all environments. Key assumptions
associated with the values selected include the following:
• The accessible volume in the air compartment encompasses the
air up to the top of the troposphere ( 10 km). (This is too
large for highly reactive chemicals and too small for very
stabl'e chemicals; e.g., the f luorocarbons.)
IIIl

• Deep soils and deep ocean waters are not considered to be
accessible to the chemical. (This will hold for chemicals with
modest halflives.)
The Level I calculations require a val;ue for the total amount of
the chemical in the environmental compartment if a real attempt is
being made to predict actual environmental concentrations. Obtaining
such a value would require either (1) extensive monitoring data on the
chemical, or (2) detailed information on emission rates, transport path
ways (and rates) and degradation rates. The time requirements for such
a data compilation or evaluation effort are significant, and thus we
have selected a route which, while only allowing the calculation of
relative amounts and concentrations of the chemical in each subcompart
ment, is rapid and still allows important conclusions to be drawn:
» The total amount of each chemical in the selected compartment
is 100 moles.
B. Description of the Model Environment *
Figure 1 provides a schematic diagram of the selected model
environment. The subcompartments selected here for study are:
1. Air 4. .Bottom sediments
2. Surface waters 5. Aquatic biota
3. Suspended sediments 6. Soils
There is no reason that fewer or more subcompartments could not be
used by other users of this method. The specific compartmentrelated
parameters used in our calculations are detailed below; subscripts
on any symbol refer to the: subcompartments identified above.
A listing of the symbols used in this (and subsequent) sections is
given in Section VII.
III2

Atmosphere
Soil
Surface Water
1 Aquatic Biota and
Suspended Solids
Bottom Sediments
FIGURE 1 SCHEMATIC OF ENVIRONMENTAL COMPARTMENT SELECTED FOR ESTIMATION
OF EQUILIBRIUM PARTITIONING OF ORGANIC CHEMICALS
Note: Diagram is not to scale. Dimensions and accessible volumes of each
subcompartment given in the text.
Ill3

1) Accessible Volumes (V.).. The volumes of .each subcompartment
that were considered accessible 'to all chemicals are as follows:
Air: V = 1 km x 1 km x 10 km(high) = 1010 m
Surface water: V~ = 1 km x 0.05 km x 3 km(deep) = 1.5 x 10 m
t
* 53
Suspended sediments : V, = V = 1.5 x 10 m
* 33
Bottom sediments : V, = 1 km x 0.05 km x 10 cm(deep) = 5 x 10 m
* 53
Aquatic biota : V = V_ = 1.5 x 10 m
Soils: V, = 1 km x 0.95 km x 15 cm(deep) = 1.4 x 10 m
o • •
2) "Concentration" of Suspended and BottomSediments and
Soil (c ). Within the accessible volumes for subcompartments 3, 4,
si
and 6, some of the volume is taken up by water or air. The sediments or
soil may thus be considered to exist at a certain "concentration"
within these volumes. The selected concentrations are:
3
. Suspended sediments : c =10 g/m
S3
Bottom sediments : c = 2 x 10 g/m
S4
Soils : c = 2 x 106 g/m3
S6
*  •
Initially the accessible volume for suspended sediments and
aquatic biota are taken to be the same as for the surface waters.
A correction factor is applied later that accounts for the fact that
suspended sediments and aquatic biota take up only a fraction of the
surface water volume. A similar correction factor is applied for
bottom sediments.
III4

3) Organic Carbon Content of Sediments and Soils (oc).. Since
we have selected to use soil and sediment adsorption .coefficients,
K , which are based upon the organic carbon content, (oc). of the
oc °
soil, this content must be specified..Values of.(oc) vary widely in
nature with" the range of 0.17.  20% encompassing most values. The
following values have been used for our Level I calculations:
Suspended and bottom sediments : (oc) = (oc), = 10%
Soils : (oc), =2%
o
4) "Concentration" of Biota in Water (B). The volume fraction
533
of biota in the surface waters is /taken to be 5 x 10 m /m . If the
density is assumed to be 1 g/cm ,fthe "concentration" is 5x10 g/g.
Mackay, in his original discussion of the biotic subcompartment,
required one additional parameter, y, the fraction of the aquatic biota
that could be considered equivalent to octanol. This was done so that
the octanol/water partition coefficient (K ) could be used in place
ow
of the bioconcentration factor (BCF) in assessing the uptake of the
chemical by biota. (Values of log K and log BCF can be related by
linear regression equations). We have decided to write our basic
equation in terms of BCF rather than y x K ., since it better describes
; °W.
what is implied in the term and shows explicitly how (or where) a
measured value of BCF may be used. In numerous cases, however, it will
be necessary to use values of BCF that have been estimated via K
ow
or some other parameter.
5) Temperature (T). A temperature of 20°C (293K) was selected
for the Level I calculations. The temperature is only used directly
in one part of the calculations (the Z factor for the air subcompart
ment), but it is an indirect factor for the other chemicalspecific
parameters (e.g., solubility, vapor pressure) which are a function
of temperature. It should be noted that many of the chemicalspecific
parameter values used here were derived at .temperatures other than
20°C, usually 25°C or some other value near room temperature. No~ correc
III5

tions were applied for the Level I calculations, since the results
would not be significantly affected by such small temperature changes.
C. . ChemicalSpecific Parameters Required
For the Level I calculations, the following chemicalspecific
input parameters are required:
• Henry's Law constant, H
• Soil and sediment adsorption coefficient, K
* oc
e Bioconcentration factor for aquatic life, BCF
• Molecular weight, MW
Values of H, K , BCF and MW were taken, when available, from a draft
oc
report by SRI, International. Although not explicitly stated in this
draft report, it should be understood that a large fraction of the
listed values are estimates and may be in error by one of the
order of magnitude or more. Values of H are usually taken as the ratio"!
of the chemical's vapor pressure (Pvo^ to its,water solubility (S).j
Values of H for 21 chemicals were not given in the SRI report and were
estimated by A. D. Little. The values we estimated, and the values of
P and S from which the values of H were derived, are listed in
Table 2. P values were estimated using a modified Watson correlation
vp
which requires a measured or estimated value of the boiling point. Most
of the S values were estimated using a measured or estimated value of
the octanol/water partition coefficient (K ) and one or more
ow
suitable regression equations relating log S to log K ; the values of
S for the two halomethanes were derived from a fragment constant
*
approach.
*
Details of the estimation' methods used are provided in two draft
chapters (Ch. 2: Solubility in Water, by W. Lyman; and Ch. 14: Vapor
Pressure, by C. Grain) which are part of a chemicalproperty estimation
methods handbook currently being prepared by A. D. Little under contract
to the U.S. Army. The report will be available in 1981.
III6

Table 2
Estimates of S, P and H for Selected Chemicals'
No.b
14.
16.
18.
20.
29.
33.
34.
60.
62.
81.
83.
84.
85.
89.
91.
108.
109.
110.
111.
112.
113.
Chemical
Endosulfan sulfate
Endrin aldehyde
Heptachlof epoxide
TCDD
2Chloronaphthalene
Methane, 
chlorodibromo
Methane,
dichlorobromo
Ether,
4bromophenyl phenyl
Bi s( 2ch loroethoxy )
methane
Phenol, 4nitro
Phenol, 2,4dimethyl
mCresol , pchloro
oCresol, ,
4,6dinitro
Phthalate, diNoctyl
Phthalate,
Butyl benzyl
Nitrosamine, dimethyl
Nitrosamine, diphenyl
Nitrosamine,
diNpropyl
Benzidine
Benzidine,
3,3'dichloro
Hydrazine,
1,2diphenyl
'P
Mol.
Wt.
422.9
381
389.2
322
162.6
208.3
163.8
249.1
173.1
139.1
122.2
142.6
198.1
391
312
74.1
198.2
130.2
184.2
253.1
184.2
s
(mg/L)
.100, 
o.iVc
(0.350)
(0.0002)
2.8
4,600
6,000
380
.
(8.1x10 )"
(1.6xl04)
(4,200)
(3850)
950
(3.0)
(2.9) .
4.9xl05
26
(9900)
890
(4)
30
P
(mm H^) ,
>•' ''&*
3.3x10
i.3xio~7
1.0xlO~7
6.1xlO~7
1.6xlO~2
(15)
(50)
(1.5xlO~ )
1
1.1x10
3.2xlO~6
(6.2xlO~2)
7.1x!0"3
— C
7.3x10
3.3xlO~5
,d
— D
8.6x10
2.7x10°
1.4xlO~5
1.6xlO~3
•7
6.8xlO~
2.9xlO~7
_5
9.2x10
« H '3
(atm'm /mole)
1.8X1010
6.5xlO~7
1.5xlO~7
1.3xlO"3
1.2xlO~3
4
8.9x10
1.8x10
6
1.3x10
_7
3.1x10
3.7xlO~?
2.4xlO~6
3.5xlO~7
2.0xlO~°
5.7xlO~6
— 1 1"
1.2x10
5.4xlO~6
1.4xlO~7 •
2.8xlO~8
10
1.8x10 1U
2.4xlO~8
_7
7.4x10
a. The values of S and P in parentheses are from the draft SRI,
International, report." The other values of S and P are estimates,
vp
III7

Table 2 footnotes (continued)
a temperature of ~20°C, by Arthur D. Little, Inc. Values of H are
derived from the S and P values as follows:
VP  . /*' '• ' '  , .' •'„/
3 P (mm Hg) . MW (g'/mole) .,
.atm . m _ vp • 6 £ ,.
1 mole ' ~ S .(mg/L) . 760 ' 
s
b. No. = index number of chemical used in subsequent listing of all organic
priority pollutants.
c. This value is an "educated guess"; it is more uncertain than other .
estimates.
d. This is a measured value from Gledhill et al. (1980).
III8

The values of H, K , BCF, and MW used for all of the priority.
pollutants are provided in Table 3. This table also provides the calcu
lated fugacity (f), which is the first parameter calculated in the
Level I approach described in the .following subsection.
t
The total mass (M) of each chemical .in the environmental compart
ment is taken as 100 moles for the Level I calculations. (See sub
section A above for rationale.).
D. Level I Equations
The basic tenet of the Mackay approach is that, at equilibrium,
the fugacity of the chemical is the same. in all subcompartments; i.e.,
This fugacity, which has the units of pressure (atm), can be regarded
as the chemical's "escaping tendency" or "corrected pressure" within
a phase.
A second major tenet is that f is proportional to the chemical's
concentration (C), at least at the low concentrations of anthropogenic
chemicals usually found in the environment. Mackay uses the symbol Z
for the proportionality constant:
C = Zf . (2)
3 3
With C in mol/m and f in atm, Z will have units of mol/m atm. 
The value of Z depends upon both the nature of the chemical and
the environment it is in. It' is also a function of temperature and
pressure. Mackay gives the following equations for the calculation
of Z in each subcompartment; the basis for these equations is discussed
more fully in his paper (op cit.):
III9 .

1. Air:
2. = 1/RT = 41.6 at 20°C (3)
53
(R = gas constant = 8.2 x 10 m atm/mol. deg.)
(T = temperature, K)
2. Surface Water:
Z2 = 1/H (= S/Pvp) (4)
*
3. Suspended sediments '
Z, = 10~6K c /H . . (5)
3 P3 S3
(K = soil adsorption coefficient)
P
or Z = 10~8(oc),K c /H (6)
^ j OC S
(K = 100 . K /(oc) )
oc p
( (oc) = % organic carbon in soil or sediment)
* • i
4. Bottom.sediments :
Z, = 10~6 K c /H (7)
4 P, s.
r4 4
or „
Z4 = 10"°(oc)4 KQC cs /H (8)
JL.
"Eqs. 5, 7, 9, and 11 are given by Mackay (op cit.). Eqs. 6,
8, and 12 (which involves the use of K in place of K and Eq. 10
which uses BCF in place of y . K ) have been used in the calculations
here*
11110

*
5. Aquatic Biota :
or
Z, = B . y . K /H , (9)
J OW
Z = B . BCF/H ' . (10)
6. Soils :
Z, = ICf6 K c /H (11)
6 ?6 S6
or
Z6 = iO8 (oc)6 KQC c /H (12)
b
With the above Zf actors, the fugacity is given by
6
f = M/ (V.) (13)
where M is the total amount of the chemical in the compartment, the
Z. values are obtained from Eqs. 3 to 12, and. the V. values are the
accessible volumes of each of the six subcompartments, as described
in subsection Bl above. When the selected values of V. and Eqs. 3,
4, 6, 8, 10 'and 12 are substituted into Eq. 13, the result is:
f = M/,(4.16 x IO11 + 1.5 x 105/H + 1.5 x 10~3(oc).K c /H
3 oc s_
+ 0.5 x 10~4(oc),K c /H + 1.5 x IO5 B (BCF)/H
4 oc s4
+ 1.4 x 10~3 (oc), K c /H) (14)
D OC S,
0
Then, with the selected values of (oc) , c arid B (see subsection B
5
above), Eq. 14 becomes:
f = MH/(4.16 x 10UH + i.5 x IO5 + 0.15 K + IO3 K
: pc , . oc
+ 7.5(BCF) + 5.6 x 103.KOC) . (15)
I1111

which may be reduced to:
£ = MH/(4.16 x 10UH + 1.5 x 105 + 6.6 x 103K + 7.5(BCF) ) (16)
oc
Equation 16 was then evaluated for all of the organic priority
pollutants using the values of H, K and BCF from Table 3; M was.
taken as 100 moles for each chemical. The calculated f values are also
given in Table 3; they range from about 10 to.10 atm.
It should be noted that, for certain classes of chemicals, just
one term in the denominator of Eq. 16 may be important. Values of H
(range ~ 10~ to 1), K (range •%. 1 to 10 ) and BCF (range «. 1 to 10 )
vary greatly. For chemicals with relatively low K and BCF values
and relatively high H valuess (i.e., hydrophylic, volatile chemicals),
the first term in the denominator will dominate and Eq. 16 reduces
to: ,
f = M/4.16 x 1011 . (17)
— 10
which is equal to 2.4 x 10 atm with M = 100 moles. Approximately
50 percent of the chemicals listed in Table 3 have f values of
~2 x 10 because of this combination of factors.
Two other points are worth noting. First, the calculated f values
are directly proportional to M, the total mass of the chemical in the
compartment. The values of f in Table 3 are for M = 100 moles. An
adjustment of f for any other value of M is thus a straightforward
ratio calculation. For example,,to obtain f for M = 10 moles, the values
of f in Table 3 would be divided by 10 (100/10 =10)..
Second, both K and BCF are measures of hydrophobicity in that
they represent the ratio of the chemical's concentration in some organic
medium (soil, biota) to that in water. A more general measure of hydro
phobicity is K , the octanol/water partition coefficient. Two fairly
general regression equations relating K to K and BCF are t
ow oc
* •  • '
Eq. 18 from Kenaga, E.E., and C.A.I, Goring (1980).
Eq. 19 from Veith et al. (1979).
11112

and
log K = 0.544 log K + 1.377 (18)
6 oc B ow
log BCF = 0;76 log K 0.23 * ' (19)
With these relationships,'Eq. 16 may be written with only two chemical
specific parameters, H and K :'"' •' •*'"'•
"*"*
f = MH/(4;l6xl011H+1.5xl05+1.6kl05(K )0^44+4.4(K )°'76) (20)
ow ow
This equation thus expresses f in termsof two, obviously important,
partition coefficients: an air/water partition coefficient (H) and
an organics/water partition coefficient (K ). These two coefficients
are not independent variables, since both depend on the hydrophilicity
(e.g, solubility) of the chemical.
Once values of f have been calculated, the mass of the chemical
in each subcompartraent, M^, is obtained from
':
v . ! . ' • • ' 
M. = f V. Z. moles '  ; ' • • (21)
111
Since in our own case 2»M, = 100 moles, the individual values of M.
are equivalent to the percent of the chemical in each subcompartment.
The calculated values of M. .(M. = mass
water, etc.). are shown in Table 4. . '
The calculated values of M. .(M. = mass in'air, M_ = mass in surface"
Once the M. values have been obtained, the'concentration of the
chemical in each subcompartment,•C., is obtained from •  •
C.^ = Z^f  mol/m3 .'. • ••••'. ' (22)
or . ' .. •.,.• :.' ' '  '•
Ci = Mi/Vi mol/m3 ' • ' ^23:)
The units of C. from Eqs. 22 and.23 are moles per cubic meter •<
1 3 3
of. the environment; i.e., moles per m of air for Cy, moles per nr of
3 • • • •
water for C2, C~, and C^,'moles per m of bottom sediments for C,,
11113 .  . .

3 •'''.'•
and moles per m of soil for C,. Concentrations of chemicals in the
o
environment are more commonly expressed on a .volume per volume basis
for the air compartment and on a weight per weight (or weight per
volume) basis for the other subcompartments. Conversion to these more
common units requires ..the use of the c values for soils and sediments,
the B value for biota, and the molecular weight (MW) of the compound.
For the environmental compartment chosen, the equations for calculating
concentrations, C.', in the more common units are:
C ' = 2.4 Mj ppt (vol/vol) * (24)
C2' = (MW)M2/0.15 ppt (wt/wt) . (25)
C3' = (MW)M3/1.5 x 10~6 ppt (wt/wt) (26)
C4« = (MW)M4 x 102 ppt (wt/wt) (27)
C5' = (MW)M5/7.5 x 10~6 ppt (wt/wt) (28)
C6' = (MW)M&/0.28 ppt (wt/wt) (29)
Equations 24 to 29 were used to calculate subcompartment concen
trations for each of the organic priority pollutants. The results are
provided in Table 5. Again, it should be pointed out that these
calculated concentrations are based upon an assumed total load (M)
of 100.'moles'of each chemical in the total compartment. But again,
the C.1 values are directly proportional to M so that adjustments may
easily be made for different estimates of M. The values of C' and
C,' are equal, since we have assumed that the organic carbon content
of the suspended and bottom sediments is the same (10%).
If only concentration ratios between two subcompartments are to
be calculated,. just the fugacity coefficients (Z) need to be calculated.
The ratio of concentrations in subcompartments i and j (cf. Eq. 22) is
simply: CJ./G.J = zi/zj •
If units of wt/vol are desired for air; use
c1' «• Mi

StepbyStep Ins t ructions r
•srta irx feifivfflj&iio ?o afto; ?e'i;itif;i.:i.;7orJ . A0 ' ». SOI CiXSJ V f rtGiJUnO '.V 9">r OKI ii'ifi 3a'.«i'iUIO%ivr.u
(1) For the pollutant of interest, obtain MW, H, K , BCF and M (mass
3.00 jriiiidw 10) . jr)oi.i.w iso :><{•*..;••'.; va no bos .HiomJipqrco:; :vu; . yH' "o:i
of chemical in mtfdel environment). H may be estimated from
>•!:) bn?, ,n;loid ~:v~i &I.UGV :s.'iC'j
(2) For the model environment, select the desired Values for the
•>
accessible volumes of each subcompartment , V (o ) , the concen
(flvj • ' " (Iov\.iov) :JC,TI ,H £ . £  ' .0
tration of soil and sediments in their respective sub compartments,
3
c (g/m ), the organic carbon content of these soils and sediments,
fcSs , i jw\:iw> • 3qq  '..'.;
oc (%) , the volume fraction of biota in the surface waters, B, and
the temperature, T (K) .
(di./ . (.iv,'i.;^5 :;qvi '''""O.! :< i". . }. \ t/ j ' v. ?'; • \ ;
(3) For the subcompartments of interest, calculate the fugacity
(\v) 3 ;jv..\jw) uq« "Of x ,K;'WM) •: ' . ,;
coefficients, Z (mol m /atm), from equations 3", 4, 6, 8, "10 and
12 (or 3, 4, 5, 7, 9 and 11 if the original Mackay approach is to
{80 x UwV;w; 3qq " y [ >: £'.*\.,KfWMj « ' /J
be used) .
^i;> (i^\.;w; y.:iq Sv.O\.H(WM) = ! D
(4). Calculate the chemical's fugacity us ing 'equation 13. (If 'equation
set 3, 4, 6, 8, 10 and 12 is used for' the Z values, and th
J .7ii'jrp3TBsiincjdu« ^::r, !i::>.r&v, ;> 3 \itv.» <•:"/ qv? y£*<.vj AS snoi;;sup:l
. . . .
accessible volumes (V ) are the same as were selected for the
?! 3 ! ti<; ft v or!T . a jcrfi .;i;i ; rt ;
model environment used here, then equation 14 may be used to
.sasrfj 3 fids j's/o .iaitiiioq s>c! ⅈor(a' ij: tioi.figA .L a Lost' fj.r Is ft h^y «>•/<«
calculate f. If, in addition, the values of (oc) , c and B are
J;)b&o.r I&:tOj b'jii(.'ja.aB (SB noqu h.'iEB
the same as in the model environment selected here, then equation
i:.r«asi 3:<3. . jnjiX7J"r.q(rio:i [fijc,:i nri:? rri I £.>.? flvirir/ rfoB9 io ,?iiiom 001 I'.i
. .
16 may be used to calculate f . )
K:rjvvrs.is«r be. :3t.>rfJ o?.. M 6n I <;ro.i >"ip<;ui vJ 3L>c»"t f.b
r»:T. ',,0 I:i a>ijjjv iilT .ts io ;.:••> jii(r:M?.=5 3fi£."! •>"; J rb ^oj Ebtifn nrf vfittr..
(5) Calculate the mass, M (mol), of the chemical in each subcompartment
Jr!OJi"!ci:> riOffsBD rj.rfi.f.y'iO a»Tj • :ff.:l j L> v (flu a 3 E sv'&ri 7;v^ s?n.f« ,'aups st£> ';"J
using equation 21. *"
'
(6) Calculate the concentration, C. (mol/m ), of the chemical in each
o') o'iii a.tasan'if.f.mosdusi ov; ri^^:i:.!.'Jrto;. j.f;\ «o.r:i6T.1n.iDno3 vine. xi.
subcompartment using either equation 22 or 23. Note that these
bs3B.i.i;VilK1} »4 oU bssm (S) s:r;:s/ioi A'C.M.O v'.MDBpiJ.! aii:3 i8i», tb:*aeiu3lfi:.> .&f
concentration units are mass per cubic meter of environment.
?:i ('IS , p!i' . io'J f SiiTfS 1 aj«i»:«.i.i^f;;:K'..'.iyv; J'J BfKii. 3 l.vT^OSi.OilOi jtO i;'l :.•}•• ^ uijT
Equations 2429 allow concentrations. C?, to be calculated and
i .^\t:s * j..">\v'> :vj.cj
»yt/ :'.'..'• '• JtvT !;>S'.t

expressed in more conventional units (ppt by volume for air and
ppt by weight for the other compartments),
11116

TABLE 3
ChemicalSpecific Input Parameters3 for
Level I Approach, and Calculated Fugacity (f)
No. Name
I. Pesticides
1. Acrolein
2. Aldrin
3. aBHC
4. BBHC
5. YBHC (Lindane)
6. 6BHC
7. Chlordane
8. DDD
9. DDE
10. DDT
11. Dieldrin
12. otEndosulfan
13. 6Endosulfan
14. Endosulfan Sulfate
15. Endrin
MW
56.06
' 365.
291.
291.
291.
291.
406.
320.
318.
354.5
381.
406.9
406.9
422.9
381.
H
5.66 x 10~5
1.7 x 10~4 .
6.0 x 10~6
4.5 x 10~7
8.16 x'10~6
2.07,x ID'7
9.4 x 10~5
2.15 x 10~8
6.79 x 10~5
1.58 x 10~5
4.57 x 10~10
C
1.0 x 10
1.91 x 10~5
1.8 x 10~10
4.0 x 10~7
K
oc
.563
1.10 x 105
4.27 x 103
4.27 x 103
4.27 x 103
4.27 x 103
1.66 x 105
8.92 x 105
5.02 x 106
4.47 x 106
1.91 x 103
0.0126
0.0126
0.0276
1.91 x 103
BCF
0.17
3.29 x 104
1.28 x 103
1.28 x 103
1.28 x 103
1.28 x 103
4.98 x 104
2.67 x 105
1.50 x 106
1.34 x 106
572.
0.00378
0.00378
0.00827
572.
f
2.39 x 10~10
2.13 x 10*"11
1.95 x 10"11
1.58 x 10~12
2.57 x 10"11
7.28 x 10~13
8.28 x 10"12
3.65 x 10"16
2.05 x 1C)"13
5.35 x 10"14
3.58 x 10~15
10
2.32 x 10
2.36 x 10"10
1.20 x 10"13
3.09 x 10"12

No. Name
16. Endrin Aldehyde
17. Heptachlor
18. Heptachlor Epoxide
19. Isophorone
20. TCDD
(2,3,7 ,8TetrachlorodIbenzopdioxin)
21. Toxaphene
II. PCB's and Related Compounds
5 22. PCB1016 (Arochlor 1016)
i
oo 23. PCB1221 (Arochlor 1221)
24. PCB1232 (Arochlor 1232)
25. PCB1242 (Arochlor 1242)
26. PCB1248 (Arochlor 1248)
27. PCB1254 (Arochlor 1254)
28. PCB1260 (Arochlor 1260)
29. 2Chloronaphthalene
III. Halogenated Aliphatics
30. Methane, Broroo (Methylbromide)
MW
381.
373.5
389.2
138.2
322.
.414.
257.9
200.7
232.2
. 266.5
299.5
328.4
' 375.7
162.6
94.94
H
6.5 x 10~7
3.95 x 10~3
1.5 x 10~7
5.75 x 10~6
1.3 x 10~3
0.21
3.3 x 10~4
1.2 x 10~4
8.6 x 10~4
1.98 x 10~3
3.6 x 10~3
2.6 x 10~3
0.74
1.2 x 10~3
0.197
K
oc
759.
1.41 x 104
246.
100.
3.80 x 106
1.1 x 103
2.1.x 105
6.6 x 103
880.
7.2 x 103
3.2 x 105
6.1 x 105
7.7 x 106
5.5 x 103
6.77
BCF
228.
4.24
73.7
30.0
1.14 x 106
330.
6.3 x 104
2.0 x 103
264.
2.1 x 103
9.5 x 104
1.8 x 105
2.3 x 106
1.68 x 103
2.03
f
1.20 x 10"11
2.27 x ID'10
8.17 x 10~12
1.80 x 10"10
5.07 x 10~12
,2.40 x 10"10
2.17 x 10"11
1.28 x 10" 10
2.36 x 10~10
2.27 x 10"10
9.97 x 10"11
5.09 x 10"11
2.06 x 10"10
,2.24 x 10~10
2.40 x 10~10

TABLE 3 (cont.)
No. Name
31. Methane, Chloro (Methylchloride)
32. Methane, Dichloro (Methylene
chloride)
33. Methane, Chlorodibromo
34. Methane, Dichlorobromo
35. Methane, Tribromo (Bromoform)
36. Methane, Trichloro (Chloroform)
37. Methane, Tetrachloro
(Carbon tetrachioride)
W'
M
71 38. Methane, Trichlbrofluoro
t1
vD
. 39. Methane,. Dtchlorpdifluoro •
40. Ethane, Chloro
41. Ethane, 1 , 1Dichloro
42. Ethane, 1 , 2Dlchloro
43. Ethane, 1,1,1Trichloro
44. Ethane, 1,1,2Trichloro
45. Ethane, 1,1,2,2Tetrachloro
46. Ethane, Hexachloro
MW
50.49
84.94
208.29
163.83
252.75
119.38
153.82
137.4
120.91
64.52
98.96
'98.98
133.41
133.41
167.85
236.74
H
0.04
2.98 x 10~3
8.9 x 10~4
1.8 x 10~3
5.44 x 10~4
2.88 x 10~3.
2.32 x 10~2
0.11
2.98
1.48 x 10"2.
4.26 x 10~3
9.14 x 10~4
3.0 x 10~2
7.42 x 10"4
3.80 x 10~4
2.49 x 10~3
K
oc
4.9
10.0
95.6
69.2
132.
50.2
502.
182. 
66.1
17.0 '
34.7
16.6
174.
64.6
251
2.29 x 104
BCF
1.47
3.00
28.7
20.8
39.6
15.4
150
54.6
I
19.8
5.10
10.4
4.98 :.
52.2
19.4
75.4
6.88 x 103
f
2.40 x 10~10
2.40 x 10~10
2.40 x 10"10
2.40 x 10~10
2.39 x 10"10
2.40 x 10~10:
2.40 x 10"10
2.40 x 10"10
2.40 x 10"10
2.40 x 10~10
2.40 x 10~10;
2.40'x 10~10
2.40 x 10"10
•2.40 x 10~10.
2.38 x 10~10
2.10 x 10~10

TABLE 3 (cont.)
NJ
O
No. Name
47. Ethene, Chloro
(Vinyl chloride)
48. Ethene, 1,1Dichloro
49. Ethene, Transdichloro
50. Ethene, Trlchloro
51. Ethene, Tetrachloro
52. Propane, 1,2Dichloro
53. Propene, 1,3Dichloro
54. Butadiene, Hexachloro
55. Cyclopentadiene, Hexachloro
IV. Ethers
56. Ether, Bis(2chloromethyl)
57. Ether, Bis(chloroethyl)
58. Ether, Bis(2chloroisopropyl)
59. Ether, 2chloroethyl vinyl
60. Ether, 4Bromophenyl phenyl
61. Ether, 4Chlorophenyl phenyl
62. Bis(2chloroethoxy) methane
MW ,
62.5
96.94
96.94
131.39
165.83
112.99
110.98
260.79
272.77
115.
143.
171.1
106.6
249.11
204.66
173.1
H
198.
0.160
6.9 x 10~2
9.10 x 10~3
2.0 x 10~2
2.31 x 10~3
1.33 x 10~3
2.56 x 10~2
1.61 x 10~2
2.1 x 10~4
1.3 x 10"5
1.1 x 10~4
2.50 x 10"7
1.3 x 10"6
2.19 x 10~4
3.1 x 10~7
K
oc
9.34
38.0
9.56
38.0
360.
57.6
29.5
1.00 x 103
1.05 x 103
1.32
15.9
69.2
7.59
6.61 x 104
1.70 x 104
5.89
BCF
2.80
11.4
2.87
11.4
100.
17.3
8.86
300.
314.
0.396
4.76
20.8
2.28
1.98 x 104
1.44 x 104
1.77
f
2.40 x 10~10
2.40 x 10""10
2.40 x 10"10
2.40 x 10~10
2.40 x 10~10
2.40 x 10~10
2.40 x 10~10
2.40 x 10~10
2.40 x 10~10
2.40 x 10~10
2.30 x 10~10
2.37 x 10~10
8.22 x 10"11
2.97 x 10~13
1.07 x 10~10
9.75 x lO'11

TABLE 3 (cont.)
K>
No. Name
V. Monocyclic Aromatics (Excluding
Phenols, Cresols, Phthalates)
63. Benzene
64. Benzene, Chloro
65. Benzene, 1 , 2Dlchloro
66. Benzene, 1 , 3Dichlofo
67. Benzene, 1,4Dichloro
68. Benzene, 1,2,4Trichloro
69. Benzene, Hexachloro
70. Benzene, Ethyl
71. Benzene, Nitro
72. Toluene
73. Toluene, 2,4Dinitrp
74. Toluene, 2,6Dinitro
VI. Phenols and Cresols
75. Phenol
76. Phenol, 2Chloro
77. Phenol, 2,4Dichloro
MW
78.12
112. 56'
147.01
147.01
147.01
181.45
284.79
106.16
: 123.11
92.13
182.14
182.14
94.1
128.56
163.0
H
_3
5.5 x 10
3
; 3. 58 x 10
_3
1.93 x 10
3
3.61 x 10
3
3.1 x 10
_3
2.31 x 10
6.79 x 10~4
o
6.58 x 10
1.31 x 10"5
3
5.17 x 10
6
4.5 x 10.
ft
7.9 x 10
_7
4.54 x 10
_5
1.03 x 10
6
2.8 x 10 °
K
oc
74.2
380.
3
2.00 x 10
3
2.00 x 10
3
2.00 x 10
A
1.02 x 10
1.45 x 106
3
1.20 x 10
40.8
339.
105.
105.
' 16.2
83.2
437.,
BCF
22.3
'114.
599.
. 599.
599.
. • — •— i
3.07 x 10J
4.34 x 105
' 361.
12.2
102.
31.4
31:4
4.87
25.0
131.
f
—in
2.40 x 10 AU
10
2.40 x 10 AU
10
2.36 x 10
10
2.38 x 10 ±u
10
2.38 x 10
10
2.25 x 10~
6.89 x 10~12
10
2.40 x 10 iu
2.23 x 10~10
10'
,2.40 x 10 u
10
1.66 x 10
10
1.91 x 10 AU
10
1.02 x 10 1U
10
2.07 x 10 AU
11
6.67 x 10

TABLE 3 (cont.)
[
K)
No . Name
78. Phenol, 2,4,6Trlchloro
79. Phenol, Pentachloro .
80. Phenol, 2Nitro
81. Phenol, 4Nitro
82. Phenol, 2,4Dinitro
83. Phenol, 2,4Dimethyl
84. mCresol, pChloro
85. oCresol, 4,6Dinitro
VII. Phthalate Esters
86. Phthalate, Dimethyl
87. Phthalate, Diethyl
88. Phthalate, DiNbutyl
89. Phthalate, DiNoctyl
90. Phthalate, Bis(2ethylhexyl)
91. Phthalate, Butyl benzly
VIII. Polycyclic Aromatic Hydrocarbons
92. Acenaphthene
MW
197.5
266.4
139.1
139.1
184.1
122.2
142.6
198.1
194.2
222.2
278.3
391.
391.
312.
154.2
H
6
4 x 10 °
2.8 x 10~6
f>
7.56 x 10
3.7 x 10"11
6.54 x 10~10
ft
2.4 x 10 °
_7
3.5 x 10
8
2.0 x 10
f>
2.15 x 10
ft
1.2 x 10
ft
4.5 x 10
ft
5.7 x 10
3.0 x 10~7
1.2 x lO'11
9.1 x 10~5
K
oc
•J
2.24 x 10°
6.03 x 104
30.9
51.3
55.
347.
381.
276.
112.
3
1.35 x 10
5
1.95 x 10
0
4.08 x 10
2.24 x 109
.1.95 x105
5.25 x 103
BCF
672.
1.81 x 104
. 9.28
15;4
16.5
104.
114.
82.7
33.7
405.
4
5.85 x 10
9
1.22 x 10y
6.72 x 108
5.85 x 104
1.58 x 103
f
—1 1
2.41 x 10 ij
7.01 x 10~13
10
2.16 x 10 u
7.57 x10~15
1.26 x 10~13
11
6.98 x 10
11
1.25 x 10
12
1.01 x 10
10
1.21 x 10 XU
11 '
1.25 x 10
13
3.50 x 10 *
17
2.12 x 10
2.03 x 10~18
9.32 x 10~19
1.25 x 10"10

TABLE 3 (cont.)
No. Name
93. Aceriaphthylene
94. Anthracene
95. Benzo(a) anthracene
96. Benzo(b) fluoranthene
97. Benzo(k) fluoranthene
98. Benzo(g,h,i) pefylene
99. Benzo(a) pyrene
100. Chrysene
i_i
M
V 101. Dibenz6(a,h) anthracene
(0
i*>
102. Fluoranthene
103. Fluorene
104. Indeno (1 , 2 , 3cd) pyrene
105. Naphthalene
106. Phenanthrene
107. Pyrene
IX. Nitrosamines and Other Nitrogen
Containing Compounds
108. Nitrosamine, Dimethyl (DMN)
m
152.2
178,0
,228.3
252.3
252.3
276.
252.
228.3.
278.4
202.3
166.2
276.3
128.2
178.2
202.3
 74.1
H
1.45 x 10~3
1.28 x 10~3
1.0 x 10~6
1.38 x 10~4
3.0 x Kf4
1.44 x IO"2
4.91 x 10~7
1.05 x 10~6
7.3 x 10~8
6.5 x IO"6
1.1 x 10~3
5.87 x IO"10
4.6 x 10~4
2.26 x 10~4
5.1 x.10"6
5.4 x 10~7
K
oc
2.89 x IO3
1.55 x IO4
2.24 x IO5
6.31 x Id5
6.31 x IO5
1.78 x IO6
6.31 x IO5
2.24 x IO5
3.24 x IO6
4.37 x IO4
4.47 x IO3
1.78 x IO6
1.07.x IO3
1.55 x IO3
4.37 x IO4
0;12
BCF
866.
4.65 x IO3
6.72 x IO4
1.89 x IO5
1.89 x IO5
5.34 x iO5
1.89 x IO5
6.72 x IO4
9.72 x IO5
1.31 x IO4
1.34 x IO3
5.34 x IO5
.. 322.
4.65 x IO3
1.31 x IO4
0.035
f
2.33 x 10~10
2.02 x 10" 10
6.76 x 10~14
3.27 x 10~12
6.99 x 10~12
8.12 x 10"11
14
1.18 x 10
7.10 x Kf 14
3. .41 x 10~16
2.23 x 10~12
2.26 x 10~10
5.00 x 10~18
2.32,x 10~10
2.16 x 10~10
1.75 x 10~12
L.44 x 10~10

TABLE 3 (cont.)
No. Name
109. Nitrosamine, Diphenyl
110. Nitrosamine, DiNpropyl
111. Benzidine
112. Benzidine, 3 , 3Dichloro
113. Hydrazine, 1 , 2Diphenyl
114. Acrylonitrile
MW
198.2
130.2
184.2
253.1
184.2
53.1
H
1.4 x 10~7
2.8 x 10~8
1.8 x 10~10
2.4 x 10~8
_7
7.4 x 10
70
K
oc
2.69 x IO3
17.0
19.5
525.
17.8
0.46
BCF
808.
5.10
5.85
157.
5.34
0.137
f
7.79 x 10~13
1.02 x IO"11
6.46 x 10~14
6.62 x IO"13
10
1.29 x 10
2.40 x 10~10
M
I
•J
a. MW = molecular weight (g/mol); H = Henry's Law constant (atm <• m /mol) ; K. = soil (and sediment)
adsorption coefficient based on organic carbon; BCF = bioconcentration factor for aquatic life.
f calculated from Eq. 16 with M = 100 moles.
Caution; A large fraction of the H, K . and BCF values are estimates which may
differ from the actual values by one order of magnitude (or more in
some cases). The. values listed here should not be considered as
reliable.
Source: Draft report by SRI, International for values of MW, H, K , and BCF except as noted in
Table 2.
oc

TABLE 4
Mass (M., Moles) of Chemical in Each Subcompartment Using Level I Approach'
No. Name
I. Pesticides
1. Acrolein"
2. Aldrin
3. orBHC
4. 8BHC
5. YBHC (Lindane)
M
M 6. 6BHC
i
fo
01 7 . Chlordane
8. DDD
9. DDE
10. DDT •
. 11. Dieldrin
12. aEndosulfan
13. 0Endosulfan
14. Endosulfan Sulfate,
15 . Endrin
Ml
99.35
8.87
8.09
6.56 x 10"1
10.70
_1
3.03 x 10
3.44
1.52,x 10~4
8.51 x 10"2
2.23 x^lO'2
1.49 x 10~3
96.52
98.15
4.98 x 10~2
1.29
,M2
6.33 x 10"1
1.88 x 10~2
4.86 x 10~
5.6 x 10"1
4.73 x 10T1
• _i
5.28 x 10
1.32 x 10"2
2.55 x 10~3
4.52 x 10"4
5.08 x 10~4
"1.18
3.48
1.85
99.83
1.16
M3
3.56 x 10~7
2.07 x 10~3
2.08 x 10~3
2.25 x 10~3
2.02 x 10T3
_
2.25 x 10~J
2.19 x 10~3
2.27 x.10"3
2.27 x 10~3
2.27 x 10^3
2.25 x 10~3
4.39 x 10~8
2.33 x 10~8
2.76 x 10~6
2.22 x 10~3
M4
2.38 x 10~3
13.78
13.84
14.97
13.45
15.02
14.62
15.15
15.13
15.14
14.97
2.92 x 10"4
1.56 x 10~4
1.84 x 10~2
14.78
M5
5.38 x 10~6
3.10 x 10~2
3.11 x 10~2
3.37 x 10~2
3.02 x 10~2
3.38
3.29 x 10~2
3.40 x 10~2
3.39 x 1

TABLE 4 (cont.)
No. Name
16. Endrin Aldehyde
17. Heptachlor
18. Heptachlor Epoxide
19. Isophorone
20. TCDD
(2,3,7, 8Tetrachlorodibenzopdioxin)
21. Toxaphene
II. PCB's and Related Compounds
22. PCB1016 (Arochlor 1016)
23. PCB1221 (Arochlor 1221)
24. PCB1232 (Arochlor 1232)
25. PCB1242 (Arochlor 1242)
26. PCB1248 (Arochlor 1248)
27. PCB1254 (Arochlor 1254)
28. PCB1260 (Arochlor 1260)
29. 2Chloronaphthalene
III. Halogenated Aliphatics
30. Methane, Bromo (Methylbromide)
Ml
5.0
94.6
3.4
74.7
2.1
100.
i :
9.0
53.3
98.4
94.5
41.5
21.2
86.0
93.2
100.
M2 
2.8
8.6 x 10~3
8.2
4.7
5.9 x 10~4
1.7 x 10"4
9.8 x 10~3
.16
4.1 x 10~2
1.7 x 10~2
4.2 x 10~3
2.9 x 10"3
4.2 x 10~5
2.8 x 10~2
1.8 x 10~4
M3
2.1 x 10~3
1.2 x 10~4
2.0 x 10~3
4. 7 x 10~4
2.2 x 10~3
1.9 x 10~7
2.1 x 10"3
1.1 x 10~3
3.6 x 10"5
1.2 x 10~4
1.3 x 10~3
1.8 x 10~3
3.2 x 10~4
1.5 x 10~4
1.2 x 10~9
M4
14 ..0
8.1 x 10"1
13.4
3.1
14.8 x 101
1.3 x 10~3
13.8
7.0
.24
.83
8.9
11.9
2.1
1.0
8.3 x 10"6
M5
3.1 x 10~2
1.8 x 10~6
5.0 x 10~2
7.03 x 10~3
3.3 x 10"2
2.8 x 10~6
3.1 x 10~2
1.6 x 10~2
5.4 x 10~4
1.8 x 10~3
2.0 x 10~2
2.6 x 10~2
4.8 x 10~3
2.4 x 10"3
1.9 x 10~8
M6
78.3
4.5
75.0
17.5
83.0
7.1 x 10~3
77.2
39.5
1.4 '
4.6
49.6.
66.9
12.0
:5.7
4.6 x 10"5

TABLE 4 (cont.)
No. Name
31. Methane, Chloro (Methylchloride)
32. Methane, Dichloro (Methylene
chloride)
33. Methane, Chlorodibromo
34. Methane, Dichlorobromo
35. l:ethane, Tribromo (Bromoform)
36. Methane, Trichloro (Chloroform)
37. Methane, Tetrachloro
M (Carbon tetrachloride)
M
iU 38.. Methane, Trichlorofluoro
39. . Methane, Dichlorodifluoro
40. Ethane, Chloro
41. Ethane, 1,1Dichloro
42. Ethane, 1 , 2Dichloro
43. Ethane, 1,1,1Trichloro :
44. Ethane, 1,1,2Trichloro
45 . Ethane ,1,1,2, 2Tetrachloro
46. Ethane, Hexachloro .
Ml
100.
100.
99.8
100.
99.6
100.
100.
100.
100.
100.
100.
100.
100.
99.8
98.9
, 87.3
M2
9.0 x 10~4
1.2 x 10~2
4.0 x 10~2
2.0 x 10~2
6.6 x 10"2
1.3 x 10~2
1.6 x 10~3
3.3 x 10~4
1.2 x 10~5
2.4 x 10~3
8.5 x 10~3
3.9 x 10~2
1.2 x 10~3
4.9 x 10"2
9.4 x 10~2
1.3 x 10"2
M3
4.4 x 10~9
1.2 x 10~7
3.9 x 10~6
1.4 x 10~6
8.7 x 10~6
6.3 x 10~7
7.8 x 10~7
6.0 x l6~8
8.0 x 10~10
4.1 x10"8
2.9 x 10"7
6.5 x 10~7
2.1.x 10"7
3.1 x 10~6
2.4 x 10~5
2.9 x 10~4
M4
2.9 x 10~5
8.1 x 10~4
2.6 x 10~2
9.2 x 10~3
5.8 x 10~2
4.2 x 10~3
5.2 x 10~3
4.0 x 10~4
5.3 x 10~6
2.8 x 10~4
2.0 x 10~3
4.4 x 10~3
1.4 x 10~3
2.1 x 10~2
.16
1.9
M5
6.6 x 10~8
1.8 x 10~6
5.8 x 10~5
2.1 x 10~5
1.3 x 10~4
9.6 x 10~6
1.2 x 10~5
8.9 x 10~7
1.2 x 10~8
6.2 x 10~7
4.4 x 10~6
9.8 x 10~6
3.1 x 10~6
4.7 x 10~5
3.5 x 10~4
4.3 x 10~3
Mfi
1.6 x 10~4
4.5 x 10~3
.14
5.2 x 10~2
.33
2.34 x 10~2
2.9 x 10~2
2.2 x 10~3
3.0 x 10"5
1.5 x 10~3
1.1 x 10"2
2.4 x 10"2
7.8 x 10"3
.12
.88
10.8

TABLE 4 (cont.)
No. Name
47. Ethene, Chloro
(Vinyl chloride)
48. Ethene, 1,1Dlchloro
49. Ethene, Transdichloro
50. Ethene, Trichloro
5i.. Ethene, Tetrachloro
52. Propane, 1,2Dichloro
53. Propane, 1,3Di.chloro
H
£ 54. Butadiene, Hexachloro
i
NJ
00 .55. Cyclopentadiene, Hexachloro
IV. Ethers
56. Ether, Bis(2chlorpmethyl)
57. Ether, Bis(chloroethyl)
58. Ether, Bis(2chloroisopropyl>
59. Ether, 2chloroethyl vinyl
60. Ether, 4Bromophenyl phenyl
61. Ether, 4Chlorophenyl phenyl
62. Bis(2chloroethoxy) methane
Ml
100.
100.
100.
100.
99.96
100.
100.
100.
100.
99.8
95.6
98.7
34.2
. .12
44.8
44.8
M2
1.8 x 10~7
2.3 x 10~4
5.23 x 10~4
4.06 x 10" 3
1.80 x 10~3
1.6 x 10~2
2.7 x 10~2
1.4 x 10~3
2.2 x 10~3
.17
2.6
.32
49.3
3.4 x 10~2
7.4 x 10"2
7.4 x 10~2
M3
1.7 x 10~12
8.6 x 10~9
5.0 x 10~9
1.5 x 10"7
6.49 x 10~7
9.0 x 10~7
8.0 x 10~7
1.4 x 10~6
2.3 x 10~6
2.3 x 10~?
4.2 x 10~5
2.2 x 10~5
3.7 x 10~4
2.3 x 10"3
1.3 x 10~3
1.3 x 10~3
M4
1.1 x 10~8
5.7 x 10~5
3.3 x 10~5
1.0 x 10~3
4.33 x 10~3
6.0 x 10~3
5.3 x 10~3
9.4 x 10~3
1.6 x 10~2
1.5 x 10~3
.28
.15
2. 5
15.1
8.4
8.4
M5
2.5 x 10"11
1.3 x 10~7
7.5 x 10~8
2.3 x 10~6
9.01 x 10~6
1.3 x 10~5
1.2 x 10~5
2.1 x 10~5
3.5 x 10~5
3. 4 x 10~6
6.3 x 10"4
3.4 x 10~4
5.6 x 10~3
3.4 x 10~2
5.3 x 10~2
5.3 x 10~2
M6
6.4 x 10~8
3.2 x 10~4
1.9 x 10~4
5.6 x 10~3
2.42 x 10"2
3.4 x 10~2
3.0 x 10~2
5.3 x 10"2
8.8 x 10~2
8.4 x 10"3
1.6
.84
14.0
84.7
46.8
46.8

TABLE 4 (cont.)
N>
VO
No.  Name
V. Monocyclic Aromatics (Excluding
Phenols. Cresols, Phthalates)
63. Benzene
64. Benzene, Chloro
65. Benzene, 1,2Dichloro
66. Benzene, 1 , 3Dichloro
. 67. Benzene, 1,4Dichloro
68. Benzene, 1,2,4Trichloro
69. Benzene, Hexachloro
70. Benzene, Ettiyl
71. Benzene, Nitro
72. Toluene .
73. Toluene, 2,4Dinitro
74. Toluene, 2,6Dinitro
VI, Phenols and Cresols
75. Phenol
76. Phenol, 2Chloro
77. Phenol, 2,4Dichloro
Ml
100.
' 99.8
98.4
99.1
99.0
93.4
2.9
99.7
92.9
99.9
68.9
79.6
42.3
86.0
27.7
M2
6.6 x 10"3
1.0 x 10~2
1.8 x 10~2
9.9 x 10~3
1.2 x HT2
1.5 x 10~2
1.5 x 10~3
5.5 x 10~3
2.6
7.0 x 10~3
5.5
3.6
33.6
3.0
3.6
M3
4.9 x 10~7
3.8 x 10~6
3.7 x 10~5
2.0 x 10~5
2.3 x 10~5
1.5 x 1Q~5
2.2 x 10~3
6.6 x 10~6
1.0 x 10~4
2.4 x 10~6
5.8 x 10"4
3.8 x 10~4
5.4 x 10~4
2.5 x 10~4
1.6 x"10~3
M4
3.2 x 10~3
2.5 x 10~2
.25
.13 .
.15
1.0
14.7
4.4 x 10~2
.70
1.6 x 10~2
3.9
2.5
3.6
1.7
10.4
M5
7.3 x 10"6
5.7 x 10~5
5.5 x 10~4
3.0 x 10~4
3.4 x 10"4
2.2 x 10~3
3.3 x 10~2
9.9 x 10~5
1.6 x 10~3
3.6 x 10~5
8.7 x 10~3
5.7 x 10~3
8.2 x 10~3
3.8 x 10"3
2.3 x 10"2
M6
1.8 x 10"2
.14
1.4
.74
.86
5.6
82.4
.24
3.9
8.8 x 10"2
21.7
14.2
20.3
9.3
58.3

TABLE 4 (cont.)
H
M
U> '
O
No. Name
78. Phenol, 2,4,6Trichlqro
79. Phenol, Pentachloro
80, Phenol, 2Nitro
81. Phenol, 4Nitro
82. Phenol, 2,4Dinitro
83. Phenol, 2,4Dimethyl
84. m^Cresol, pChloro
85. oCresol, 4,6Dinitro
VII. Phthalate Esters
86. Phthalate, Dimethyl
87. Phthalate, Diethyl
88. Phthalate, DiNbutyl
89. Phthalate, DiNoctyl
90. Phthalate, Bis(2ethylhexyl)
.91. Phthalate, Butyl benzly
VIII. Polycyclic Aromatic Hydrocarbons
92. Acenaph thene
Ml
10.0
.29
89.9
3.1 x 10~3
5.2 x 10"2
29.0
5.2
.42
50.1
5.2
.15
8.8 x 10~6
8.4 x 10~7
3.9 x 10" 7
52.0
M2
.90
3.8 x 10~2
4.3
30.7
29.2
4.4
5.3
7.6
8.4
1 1.6
.12
5.6 x 10~7
1.0 x 10~6
1.2 x 10~6
.21
M3
3
2.0 x 10
2.3 x 10~3
4
1>3 x 10
1.6 x 10"3
1.6 x 10~3
1.5 x 10~3
2.0 x 10~3
2.1 x 10~3
9.4 x 10~4
2.1 x 10~3
2.3 x 10~3
2.3 x 10~3
2.3 x 10~3
2.3 x 10~3
1.1 x 10~3
M4
13.5
15.1
.88
10.5
10.7
10.1
13.6
13.9
6.2
14.1
15'. 1
15.1
15.1
15.1
7.2
M5
_2
3.0 x 10
3.4 x 10"2
_3
2.0 x 10
2.4 x 10~2
2.4 x 10~2
2.3 x 10~2
3.0 x 10~2
3.1 x 10~2
1.4 x 10"2
3.2 x 10~2
3.4 x 10~2
3.4 x 10~2
3.4 x 10"2
3.4 x 10"2
1.6 x 10~2
Mfi
75.6
84.5
4.9
58.8
60.0
56.5
75.9
78.0
35'. 2.
79.1
84.7
84.8
84.8
84.8
40.4

TABLE 4 (cont.)
No. Name
93. Acenaphthylene
94. Anthracene
95. Benzo(a) anthracene
96. Benzo(b) fluoranthene
97. Benzo(k) fluoranthene
98. Benzo(g,h,i) perylene
99. Benzo(a) pyrene
100. Chrysene
101. Dibenzo(a,h) anthracene
102. Fluoranthene
103. Fluorene
104. Ihdeno(l,2,3cd) pyrene
105. Naphthalene
106. Phenanthrene
107. Pyrene
IX. Nitros amines and Other Nitrogen
Containing Compounds
108. Nitrosatnine, Dimethyl (DMN)
Ml
96.9
83.9
2.8 x 10~2
1.4
2.9
33.8
4.9 x 10~3
3.00 x 10~2
1.4 x 10~4
.93
93.9
2.1 x 10~6
96.4
90.0
.73
59.8
M2
2.4 x 10~2
2.4 x 10~2
1.0 x 10~2
3.6 x 10~3
3.5 x 10"3
8.5 x 10~4
3.6 x 10~3
1.0 x 10~2
7.0 x 10~4
5.1 x 10~2
3.1 x 10~2
1.3 x 10~3
7.6 x 10~2
.14
5.2 x 10~2
40.0
M3
7.0 x 10~5
3.7 x 10~4
2.3 x 10~3
2.2 x 10~3
2.2 x 10"3
1.5 x 10~3
2.3 x 10~3
2.3 x 10~3
2.3 x 10~3
2.2 x 10~3
1.4 x 10~4
2.3 x 10~3 '
8.1 x 10"5
2.2 x 10~4
2.3 x 10"3
4.8 x 10~6
M4
.46
2.4
15.1
14.9
14.7
10.0
15.1
15.1
15.1
15.0
.92
15.1
5.4 x 10"1
1.5
15.0
3.2.x 10~2'
"3
1.0 x 10~3
5.5 x 10~3
3.4 x 10~2
3.4 x 10~2
3.3 x 10~2
2.3 x 10~2
3.4 x 10~2
3.4 x 10~2
3.4 x 10'2
3.4 x 10~2
2.1 x^lO~3
3.4 x 10~2
1.2 x 10~3
3.3 x 10~2
3.4 x 10~2
7.0 x 10~5
M6
2.6
13.7
83.7
83.7
82.3
56.2
84.8
84.8
84.8 ;
84.0
5.1
84.8
3.0
84.2
84.2
.18

TABLE 4 (cont.)
M
M
I
U)
M
No . Name
109. Nitrosamine, Diphenyl
110. Nitrosamine, DiNpropyl
111. Benzidine
112. Benzidine, 3 , 3Dichloro
113. Hydrazine, 1 , 2Diphenyl
114. Acrylonitrile
Ml
.32
4.3
2.7.x 10"2
.28
53.5
100. .
M2
.83
54.8
53.8
4.1
26.1
5.2 x 10"7
M3
2.2 x 10"3
4
9.3 x 10
1.0 x 10~3
2.2 x 10~3
4.6 x 10~4
2.7 x 10"13
M4
15.0
6.2
7.0
14.5
3.1
1.6 x 10~9
M5
3.4 x 10~z
_2
1.4 x 10
1.6 x 10~2
3.2 x 10~2
7.0 x 10~3
3.5 x 10~12
M6
83.8
34.8
39.2
81.1
17,3
8.8 x 10~9
a.
Calculated from Eq. 21 with M  100 moles. Thus, the individual M values (in moles) are equivalent
to the percent in each subcompartment. The subscripts on M identify the environmental
subcompartments as follows:
1. Air
2. Surface water
3. Suspended sediments
4. Bottom sediments
5. Aquatic biota
6. Soils

TABLE 5
Calculated Concentrations (ppt) of Chemicals in Each Subcompartment
Using Level I Approach2
No. Name
I. Pesticides
1. Acrolein
2. Aldrin
3. aBHC ,
4. 8BHC ...'..
5. YBHC (Lindane)
6. 5BHC
7. Chlordane
8. DDD ! .
9. DDE
10. DDT
11. Dieldrin
12. otEndosulfan
13. 8Endosulfan
14. Endosulfan Sulfate
15. Endrin.
«;"
240.
210.
19.
1.6
26.
7.3 x 10~l
8.3
3.6 x 10~4
..20
5.3 x 10~2
3.6 x 10~3
230.
240.
 .12
3.1
C2
240.
46.
940.
1000.
920.
1000.
36.
5.4
.96
1.2
3000.
940.
5000.
'2.8 x 105
3000.
C^ and C£
13.
5.0 x 105
4.0 x 105
4.4 x 105
3.9 x 105
4.4 x 105
5.9 x 105
4.8 x 105
4.8 x 105.
5.4 x 105
5.7 x 105
12.
6.3
780.
5.6 x 105
C5
40. ' '
1.5 x 106
1.2 x 106
1.3 x 106
1.2 x 106
1.3 x 106
1.8 x 106.
1.5 x 106
1.4 x 106 i
1.6 x 106
1.7 x lO6
36.
19.
2300.
1.7 x lO6
C6.
2.7
1.0 x 105
8.1. x 104
8.7 x 104
7.8 x 104
8.7 x 104
\
1.2 x 105
9.7 x 104
9.6 x 104
1.1 x 105
1.1 x 105
' 2.4
1.3
160.
1.1 :x 105

TABLE 5 (cont.)
No. Name
. 16. Endrin Aldehyde
17. Heptachlor
18. Heptachlor Epoxide
19. Isophorone
20. TCDD
(2,3,7, 8Tetrachlorodibenzopdioxin)
21, Toxaphene
II. PCB's and Related Compounds
S 22. PCB1016 (Arochlor 1016)
r
£ 23. PCB1221 (Arochlor 1221)
24. PCB1232 (Arochlor 1232)
25. PCB1242 (Arochlor 1242)
26. PCB1248 (Arochlor 1248)
27. PCB1254 (Arochlor 1254)
28. PCB1260 (Arochlor 1260)
29. 2Chloronaphthalene
III. Halogenated Aliphatics
30. Methane, Bromo (Methylbromide)
Ci
12.
230.
8.2
180.
. 5.1
240.
220.
130.
240.
230.
100.
51.
210.
• 220.
240.
C2
7000.
220.
2.1 x 104
4.3 x 103
1.3
.47
17.
210.
64.
31.
8.3
6.4
.10
30.
.12
C' and C?
5.3 x 105
3.0 x 104
5.2 x 105
4.3 x 104
4.8 x 105
52.
3.6 x 105
1.4 x 105
5600.
2.2 x 104
2.7 x 105
3.9 x 105
8.1 x 104
1.7 x 104
7.8 x 10T2
C5
1.6 x 106
91.
1.6 x 106
1.3 x 105
1.4 x 106
160.
1.1 x 106
4:3 x 105
1.7 x 104
6.4 x 104
7.9 x 105
1.2 x 106
2.4 x 105
5.1 x 104
 24
C6
1.1 x 105
6.1 x 103
1.0 x 105
• 8.6 x 103
9.5 x 104
10.
7.1 x 104
2.8 x 104
1100.
4.4 x 103
5.3 x 104
7.8 x 104
1.6 x 104
3000.
1.6 x 10~2

TABLE 5 (cent.)
w
u>
No. Name
31. Methane, Chloro (Methylchloride)
32. Methane, Dichloro (Methylene
chloride)
33. Methane, Chlorodibromo
34. Methane, Dichlorobromo
35. Methane, Tribromo (Bromofonn)
36. Methane, Trichloro (Chloroform)
37. Methane, Tetrachloro
(Carbon tetrachlorlde)
38. • Methane, Trichlorofluoro
39. Methane, Dichlorodifluoro
40. Ethane, Chloro
41; Ethane, 1,1Dichlpro
42. Ethane, 1 , 2Dlchloro
43. Ethane, 1,1,1Trichloro
44. Ethane, 1,1,2Trichloro
45. Ethane, 1,1,2,2Tetrachloro
46. Ethane, Hexachloro
Ci
240.
240.
. .240.
240.
240.
240.
240.
240.
240.
240.
240.
240. '
240.
240.
240.
210.
C2
.30
6.9
56.
22.
110.
10.
1.6
.30
9.8 x 10" 3
. 1.0
5.6
26.
1.1
43.
110.
20.
C' and C'
.15
6.9
540. ..
150.
1500. •'";
50.
. 80. '  : 
' 5.5
6.4 x 10~2
1.8 ""
19.
43.
19.
280.
260.
4.6 x 104
C5
.45
21.
1600.
450.
4400.
150.
—240.
16.
.19
5.3
58.
130.
56.
840.
7900.
1.4 x 105
C6
3.0 x 10~2
1.4
110.
30.
 290.
10.
16.
1.1
.1.3 x 10~2
.36
3.9
8.6
37
56.
530.
9.1 x 103

TABLE 5 (cont.)
H
I
w
No. Name ,
47. Ethene, .Chloro
(Vinyl chloride).
48. Ethene, 1 , 1Dichloro
49. Ethene, Transdichloro
50. Ethene, Trichloro
51. Ethene, Tetrachloro
52. Propane, 1,2Dichloro
'53. Propene, 1 , 3Dichloro
54. Butadiene, Hexachloro
55. Cyclopentadiene, Hexachloro
IV. Ethers
56. Ether, Bis(2chloromethyl)
57. Ether, Bis(chloroethyl)
58. Ether, Bis(2chloroisopropyl)
59. Ether, 2chloroethyl vinyl
60. Ether, 4Bromophenyl phenyl
61. Ether, 4Chlorophenyl phenyl
62. Bis(2chloroethoxy) methane
C£ b
240.
240.
240.
240.
240.
240.
240.
240.
240.
240.
230.
240.
82.
.30
100.
97.
C2
7.6 x 10~5
.15
.34
3.5
2.00
12.
20.
2.4
4.1
130.
2500.
370.
3.5 x 104
57.
100.
5.4 x 104
C^ and C",
7.1 x 10"5
.55
.32
.13.
72.
68.
59.
240.
430.
17.
4000.
2600.
2.7 x 104
3.8 x 105
1.7 x 105
3.2 x 104
c;
2.1 x 10~4
1.7
.97
40.
200.
200.
180.
.730.
1300.
52.
1.2 x 104
7700.
8.0 x 104
1.1 x 106
1.4 x 106 .
9.6 x 104
Cfi
1.4 x 10~5
.11
6.5 x 10~2
2.6
14.
14.
12.
49.
85.
3.5
800.
510.
5.3 x 103
7.5 x 104
3.4 x 104
6400.

TABLE 5 (cont.)
No. Name
V. Monocyclic Arotnatics (Excluding
Phenols, Cresols, Phthalates)
63. Benzene
64. Benzene, Chloro
65. Benzene, 1,2Dichloro
66. Benzene, 1 , 3Dichloro
67. Benzene, 1,4Dichloro
68. Benzene, 1,2,4Trichloro
H
H 69. Benzene, Hexachloro :
u> • , ' • .
70. Benzene, Ethyl
71. Benzene, Nit ro
72. Toluene ;
73. Toluene, 2,4Dinitro
74. Toluene, 2,6Dinitro
VI. Phenols and Cresols • ;
75. Phenol
76. Phenol, 2Chloro
77. Phenol1, 2 , 4Dichloro
Cl
240.
240,
240.
240.
240.
220.
6.9
240. '
220.
240.
170.
190.
100.
210.
67,
C2
3.4
7.5
: 18.
9.7
11.
18.
2.9
3.9
2100..
.4.3
6700.
4400.
2.1 x 104
2600.
3900.
C' and C£
25.
290.
3600.
1900.
2300.
1.8 x 104
4.2 x 105
460.
8600.
150.
7.0 x 104
4.6 x 104
3.4 x 104
2.1 x 104 .
1.7 x 105
C5
76.
860.
1.1 x 104
5800.
6800.
5.4 x 104
1.3 x 106
140Q.
2.6 x 104
" ' 440.
2.1. x 105
1.4 x 105
' 1.0 x 105
6.4 x 104
5.1 x 105
r'
L6
5.1
57.
720.
390.
450.
3600.
8.4 x 104
93.
1700.
29.
1.4 x 104
9300
6.8 x 103
4300. '
3.4 x 104

TABLE 5 (cont.)
No. Name
78. Phenol, 2,4,6Trichloro
79. Phenol, Pentachloro
80. Phenol, 2Nltro
81. Phenol, 4Nitro
. 82. Phenol, 2,4Dinitro
83. Phenol, 2,4Dimethyl
84. mCresol, pChloro
H 85. oCresol, 4,6Dlnitro
H
tl> VII. Phthalate Esters
00
86. Phthalate, Dimethyl
87. Phthalate, Diethyl
88. Phthalate, DiNbutyl
89. Fnthalate, DlNoctyl
90. Phthalate, Bis(2ethylhexyl)
91. Phthalate, Butyl benzly
VIII. Polycyclic Aromatic 'Hydrocarbons
92. 'Acenaphthene
Cib
24.
.70
220.
7.6xlO"3
.13
70 :
12.
1.0
120.
13.
.35
2.1xlO~5
2.0xlO~6
9. 3x10 ~7
130.
r'
C2
1200.
67.
4000.
2.8 x IO4
3.6 x IO4
3600.
'5000.
1.0 x IO4
1.1 x IO4
2300.
22.
1.5 x 10~3
2.6 x 10~3
24.
210. .
C' and C'
2.7 x IO5
4.0 x IO5
1.2 x IO4..
1.5 x IO5
2.0 x IO5
1.2 x IO5
1.9 x IO5
2.8 x IO5
1.2 x IO5
3.2 x IO5.
4.2 x IO5
5.9 x IO5
5.9 x IO5
4.7 x IO5
1.1 x IO5
C5 :
8.0 x IO5
1.2 x IO6
3.7 x IO4
4.4 x IO5
5.9 x IO5
3.7 x IO5
5.8 x IO5
8.3 x IO5
3.7 x IO5
9.4 x IO5
1.3 x IO6
1.8 x IO6
1.8 x io6 :
1.4 x io6 :
3.4 x.105 . ,
C6
5.3 x IO4
8.0 x IO4
2500.
2.9 x IO4
3.9 x IO4
2.5 x IO4
3.9 x IO4
5.5 x IO4
2.4 x IO4
6.3 x IO4
8.4 x IO4
1.2 x IO5. ;
1.2 x IO5 :
9.5 x IO4
2.2 x IO4

TABLE 5 (cont.)
No. Name
93. Acenaphthylene
94. Anthracene
95. Benzo(a) anthracene
96. Benzo(b) fluoranthene
97. Benzo(k) fluoranthene
98. Benzo(g,h,i) perylene
99. Benzo(a) pyrene
100. Chrysene
101. Dibenzo(a,h) anthracene
102. Fluoranthene
103. Fluorene
104. Indeno(l,2,3cd) pyrene
105. Naphthalene
106. Phenanthrene
107. Pyrene
IX. Nitr os amines and Other Nitrogen
Containing Compounds
108. Nitrosamine, Dimethyl (DMN)
'ib
230.
200.
6.7 x 10~2
3.3
7.0
.81.0
1.2 x 10~2
7.1 x 10~2
3.. 4 x 10~4
2.2
230.
5.0 x 10~6
230.
220.
•1.8
140.
C2
250.
28.
15.
6.0
5.9
1.6
6.0
15.
13.
' 69.
.34. .. .
2.4
65.
170.
70.
2.0 x 104
C" and C£
7100.
4.3 x 104
3.5 x105
. 3.8 x 105
3.7 x 105
2.8 x 105
3.8 x 105
3.5 x 105
4.2 x 105
3.0 x 105
1.5 x 104
4.2 x 105
6.9 x 103
2.6 x 104
3.0 x 105
240.
C5
2.1 x 104
1.3 x 105
1.0 x 106
1.1 x 106
1.1 x 106
8.3 x 105
1,1 x 106
1.0 x 106
4.2 x 105
9.1 x 105
4,6 x 104
4.2 x 105
2,1 x 104,
7.9 x 105
9.1 x 105
690.
%
1400.
8700.
6.9 x 104
7.5 x 104
7.4 x 104
5.5 x 104
7.6 x'lO4
6.9 x 104
8.4. x 104
.6.1 x 104 .
3.0 x 103
8.4 x 104
i.4 x 103
5.3 x 103
6.1 x 104
47.'

TABLE 5 (eont.)
No. Name
109. Nitrosamine, Diphenyl
: 110. Nitrosamine, DiNpropyl
111. Benzidine
112. Benzidine, 3,3Dichloro
113. Hydrazine, 1,2Diphenyl
114. Acrylonitrile
M
c b
Cl
.78
. 10.
6.4 x 10~2
.66
130.
240.
C2
1100.
4.8 x 104
6.6 x 104
7000.
3.2 x 104
1.8 x 10~4
C' and C£
3.0 x 105
8.1 x 10
1.3 x 105
3.7 x 105
5.7 x 104
8.4 x 10~6
r"
L5
8.9 x 105
2.4 x 105
.3.9 x 105
1.1 x 106 '
1.7 x 105
2.5 x 10~5
C6
5.9 x 104
1.6 x 104
2.6 x 104
7.3 x 104
1.1 x 104
1.7 x 10~6
w
V a. Calculated from Eqs. 2429. C£ is in units of ppt (vol/vol) ; all other values are in units of ppt
o (wt/wt). Calculations assume 100 moles of the chemical are contained within the total environmental
compartment. The subscripts on C identify the environmental subcompartments as follows:
1. Air
2. Surface water
3. Suspended sediments
4. Bottom, sediments
5. Aquatic biota
6. Soils
Note that concentration ratios are independent of the total mass in the environment and the volumes
of the individual subcompartments.
•3 '
b. To .convert air concentrations to ng/m , multiply the value of C, given here by MW/24.

', IV. CALCULATIONS USING NEELY'S APPROACH
A. Basis for Approach
Researchers at the Dow Chemical Co. (Midland, MI) have investigated
the distribution of a number of chemicals after placement in a simulated
aquatic/terrestrial ecosystem (Neely, 1978a, 1978b). A scenario (Blau
and Neeley, 1975; Neely and Blau, 1977) was used involving the introduc
tion of 0.15 g/hr of the test chemical into the ecosystem for a30day
period (Neely, 1978c). This was followed by a 30day clearance period.
The percent of .the test chemical in air, water and soil was determined
after the first 30day period. The halflife for clearance from fish was
determined during the 30day clearance period. A brief description of
the ecosystem used .in these tests is shown in Table 6.
The test set of chemicals used, along with their relevant properties,
are shown in Table 7. The percent of each chemical found in water, soil,
and air  and the fish clearance rate  are shown in Table 8.
Four regression, equations were found to describe the results of these
tests in a statistically significant manner. They are:
% in Air • 0.247(1/H) + 7.9 log S + 100.6 (30)
% in Water  0.054U/H) 11.32 ' (31)
% in Soil = 0.194(1/H) 7.65 log S  1.93 (32)
log t1/2  0.0027(1/H) 0.282 log S + 1.08 (33)
where H = Henry's Law Constant = PV /S
S = water solubility (mM/L)*
P = vapor pressure (mm Hg)
fcl/2 = halflife for clearance from fish in ecosystem (hr)
To convert values of S from mg/L (e.g., the values in Table 6)
to mM/L, divide by the molecular weight.
IV1

Table 6
Description of the Model.Ecosystem Used by Neely
Parameter .  Values
8 3
Volume of Water 3.6 x 10 cm
Average depth of water 89 cm
Total weight of soil 1.5 x 10 7 ga*
% organic matter in soil 0.13%
Total weight of fish 8,580g
Weight of average fish 15g
Rate of chemical addition 0.15 g/hr
s
Duration of chemical addition 30 days
Clearance period 30 days
2
a. This is based on a conversion factor of 3.7 g of soil per cm for
a 2.5 cm layer.
Source: Neely (1978c)

Table 7
Properties of a Series of Chemicals Tested in
the.Simulated Aquatic Ecosystem
Toluene
pDichlorobenzene
Tr ichloroben zene
Hexachlorobenzene
Diphenyl
Trichlorobiphenyl
Tetrachlorobiphenyl
Pentachlorobiphenyl •
DDT
Perchloroethylene
Molecular •
Weight
92
147
180
285
154
256
291
325
350 '
166
Vapor Water "
 Pressure . Solubility
(nun Hg) (ppm)
 30 ." 470
1 . ' 79
0.5 . 30
M0~5 • • . '• • 0.035
9.7 x 10~3 ' 7.5
1.5 x 10~3 . 0.05 •
4.9 x 10~4 6.05
7.7 x 10"5 0.01
10~7 . 1.2 x 10~3
14 150
Source: Neely (1978a).
iv:

Table 8
Distribution of the Chemicals Shown in Table 7 in the Various
Compartments of the Simulated Ecosystem
Chemical
Toluene
pDichlorobenzene
Trichlorobenzene
Hexachlorobenzene
Diphenyl
Tr i chlo rob ipheny 1
Te t r achlo rob ipheny 1
Pentachlorobiphenyl
DDT
Perchloroethylene
Water, %
0.9 (1.33)b
.1.24 (1.31)
1.33 (1.34)
3.57 (1.98)
2.27 (1.59)
1.38 (1.33)
1.5 (1.34)
1.5 (1.34)
1.26 (3.17)
1 (1.32)
Soil, %
0.4 (MD)
1.28 (0.24)
2.06 (4.09)
39.4 (31).
5.4 (9)
15.2 (26)
17 (27)
21 (33)
67.5 (46.5)
1 fcO)
Air, %
98.6 (VLOO)
97.5 (98) .
96 (94)
56 (68)
92.2 (89)
83 (71)
81 (71)
77 (65)
28 (49)
98 (100)
•t1/2 from
fish3, h
10 (7.,6)
15 (H)
17 (20)
162 (164)
27 (29)
96 (134)
104 '(139)
229 (226)
915 (517)
14 (12)
This is the time for clearance from the fish in the simulated aquatic
ecosystem once addition of chemical was terminated.
The numbers in parenthesis were estimated from the regression equations.
Source: Neely (1978a)
IV4

Table 8 shows the predicted percentages (and t ,2 values) for the test
set of chemicals used by Dow.
'
It should be pointed out that the use of Equations 30 to 33 were
not Intended by Neely to provide the user with quantitative predictions of
environmental concentrations that would be an end in themselves. These
regression equations were proposed as part of a decision tree (Neeley,
1978a) which can lead the user to a decision on what, if any, additional
environmental tests should be carried out on a chemical of concern. The
percent values calculated are simply used to rank a chemical with regard
to its potential as an air,* water, soil, and/or aquatic biota pollutant.
The decision tree proposed by Neely (1978a) included the" following cut
off points :
Compartment . .If . Tests to 'be Conducted
Air >90% Photodegradation; model impact "on
stratosphere
Water >2% Degradation (chemical and biological)
in water
Soil >4% Degradation (chemical and biological)
in soils
Fish ti/2 ^OO hrs. Bioconcentration factors in aquatic
biota; metabolic degradation/elimination.
The decision tree also involves considerations of the use pattern
(e.g., confined vs dispersive) of the chemical and its physical form
(polymers are given a low ranking) . .
A final comment on Equations 3033 is required. This set of equa
tions has been normalized so that the sum of the percentages in air,
water and soil should sum to approximately 100% for any chemical. While
it is recognized that, in reality, the percent in any one compartment
cannot be >100 or <0%, the regression equations may yield values outside
these values for some chemicals. This is to be expected due to a combina
IV5

tion of experimental errors and the inability of the relativelysimple
regression equations to explain allof the variability in the measured
data.
B. Sample Calculations
The test set of compounds selected for use is shown in Table 9
along with the input data required for each chemical. These input data
were obtained from a draft report by SRI, International (Menlo Park, CA).
The test set consists of twenty chemicals representing a variety of
chemical classes.
Equations 30 to 33 were applied to each of the test chemicals.
The results are shown in Table 10. Underneath the calculated values for
% in air, water and soil are the corresponding values (M.., M and Mfi,
respectively) from the Level I fugacity calculations (Table 4).
The results of the Neely approach shown in Table 10 are somewhat
disturbing if attention is focused on the unrealistic percentages associ
ated with some chemicals. Percentages <0% or >100% were associated with
nearly onehalf of the test set (9 out of 20 chemicals). The "Total %"
value is unrealistic for only one chemical, 2,4dinitrophenol.
If, however, the numbers in Table 10 are only used  as described in
A above  to decide if additional tests are required, then the results atfe
meaningful for essentially the whole test set. The chemicals that exceed
the cutoff points associated with Neely1s decision tree are listed below.
(Text continues on page IV12)
1V6

Table 9
Chemicals and Input Data Used with Neely's Equations
No. Name
I. Pesticides
2. Aldrin
5. YBHC (Lindane)
17. Heptachlor
II. PCB's and Related Compounds
23. PCB1221 (Arochlor 1221)
24. PCB1260 (Arochlor 1260)
III. Halogenated 'Aliphatics
32. Methane, Dichloro
(Methylene chloride)
48. Ethene, 1,1Dichloro
54. Butadiene, Hexachloro
IV. Ethers
56. Ether, Bis(2chloromethyl)
61. Ether, 4chlorophenyl phenyl
V. Monocylic Aromatics (Excluding Phenols',
Cresols, Phthalates)
67. Benzene, 1,4Dichloro •
73. Toluene, 2,4Dinitro
MW •
(g)
365
291
373.5
200.7
375.7
84.94
96.94
260.79
115
204.66
. 147.01
182 . 14
Pvp
(mm Hg)
6 x 10"6
1.6 x 10~4
3.0 x 10~4
6.7 x 10~3 .
4.05 x 10~5
362.4
591
0:15 "•
30
2.7 x 10~3..
1.18 • ;
5.1 x 10~3 .
S
(mg/L)
.017
7.52
0.056
15
.0027
20,000
• 400
2
2.2 x 104
3.3
79
270
1/H
(mm Hg*m3/mole)
7.76
161.51
.50
11.2
1..77 x lO'1
6.50 x 10"1
6.98 x 10~3
5.1 x 10~2
6.38
5.97,
4.55 x lO'1 .
290.7 .

Table 9 (continued)
No . Name
VI Phenols and Cresols
77. Phenol, 2,4Dichloro
82. Phenol, 2,4Dinitro
VII. Phthalate Esters.
87. Phthalate, Diethyl
90. Phthalate, Bis(2Ethylhexyl)
VIII. Polycylic Aromatic Hydrocarbons
93. Acenaphthylene
99. Benzo(a)pyrene
105 . Naphthalene
IX. Nitrosamines and Other NitrogenContaining
Compounds
114. Acrylonitrile
MM
(g)
163
184.1
222.2
391
152.2
252
; 128.2
I
^53.1
P
vp
(mm Hg)
5.9 x 10"2
1.49 x 10"5
3.5 x 10~3
2 x 10~7
2.9 x 10~2
5.6 x 10~9
8.7 x 10~2
100
S
(mg/L)
4.6 x 103
5.6 x 103
896
0.4
3.93
3.8 x 10"3
31.7
7.9 x 104
1/5
(mm Hg , /mole)
478.3
2.04 x 10"1"6
1.15 x 103
5.12 x 103
.89
2.69 x 103
2.84
14.88

Table 10
Results of Calculations Using the Neely Approach3
No . Name
I. Pesticides
2 . Aldrin
5. Y BHC (Lindane) •
17. Heptachlor . .
II. PCB's and Related Compounds
23, PCB1221 (Arochlor) 1221
28. PCB1260 (Arochlor) 1260
III. Halogenated Allphatics
32. Methane, .Dichloro
• (methylene chloride)
48. Ethene,l,lDichloro
54. Butadiene, Hexachloro
% in Air
.64.5
(8.87)a
48.2
(10.7)
70.3
(94.6)
88.9
(53.3)
59.9
(86.0)
119.2
(xlOO)
105.5
(^100)
83.9
(VLOO)
% in Water
1.7
(0.02)a
10.0
(10.47)
1.3
(0.009)
1.9
(0.16)  .
1* 5
(4 x 10 °)
1.4
(0.01)
1.3
(2 x 10~4)
1.3
(0.001)
% in Soil
32.7
(77.3)a
41.5
(75.3)
27.4
(4.5)
8.9
(39.5)
37.5
(12.0)
19.9 ,
(4 x 10"J)
6.6
(3 x 10 4)
14.3
(.05)
Total %
98.9
99.7
99.0
99.7
98.7
100.6
100. 0
99.5
fcl/2 ^hrs'^
210.2
92.0
144.4
26.8
339.6
2.6
8.1
47.5
f
VO

Table 10 (continued)
No. Name
IV. lEthers
56. Ether, Bis (2Chloromethyl)
i
61. Ether, 4Chlorophenyl Phenyl
i
V. Monocylic Aromatics (Excluding
Phenols, Cresols, Phthalates)
'67. Benzene, 1 , 4Dichloro
•
73. Toluene, 2,4Dinitro
i
VI. Phenols and Cresols
77. Phenol, 2,4Dichloro
82. Phenol, 2,4Dinitro
VII. Phthalate Esters
87. Phthalate, Diethyl
90. Phthalate, Bis(2ethylhexyl)
% in Air
117.1
(99.8)
85.0
(44.8)
98.4
(99.0)
30.2
(68.9)
6.1
(27.7)
5.0 x 105
(0.05)
179.2
(5.2)
1190
(8 x 107)
% in Water
% in Soil
1.7 18.1
(0.17) (0.008)
1.6 12.9
(7.4 x 10"2) (46.8)
1.3 22
(0.01) . (0.86)
17.0
(5.5)
27.1
(3.6)
1.1 x 105
(29.2)
63.5
(1.6)
277.5
(1 x 10~6)
53.2
(21.7)
79.8
(58.3)
4.0 x 105
(60.0)
216.9
(79,1)
1010
(84.8)
Total %
100.6
99.5
99.9
100.3
100.8
2.14 x 103
101.3
104.4
Cl/2 (hrs')
2.8
40.0
14.4
65.5
91.7
99
>9.9 x 10
1.0 x 10 4
5.4 x 1015
f

Table 10 (continued)
VIII. Polycyclic Aromatic Hydrocarbo
93. Acenaphthylene
99. Benzo(a)pyrene
105. Naphthalene
IX Nitrosamines and Other Nitrogen
Containing Compounds
114. Acrylonitrile
% in Air
as
8?;s
(96.9)
600
(0.005)
95.1
(96.4)
122 LO
( 100)
% in Water
1.4 ,
(0.02)
147
(0.004)
1.5
(0.08)
2<1 7
(5 x 10 ')
% in Soil
10.4
(2.6)
557
(84.8)
3.3
(3.0)
23.3 Q
(9 x 10 *)
Total %
99.6
101.5
99.8
100.8
tl/2 (hrs*^
33.9
5.1 x 109
18.1
1.68
a. Vales in parenthesis are the corresponding results (K., M and M,) from the Level I fugacity
calculations (Table 3). ..

Air Pollutants
(% in Air >9Q%)
Methane, dichloro
Ethene, 1,1dichloro
Ether, BIs(2chloromethyl)
Benzene, 1,4dichloro
Naphthalene
Acrylonitrile
Water Pollutants
(% in Water >2Z)
YBHC
Toluene, 2,4dinitro
Phenol, 2,4dichloro
Phenol, 2,4dinitro
Phthalate, diethyl
Phthalate, Bis(2ethyl
hexyl)
Benzo(a)pyrene
Acrylonitrile
Soil Pollutants
(% in Soil >4%)
Aldrin
YBHC
Heptachlor
PCB1221
PCB1260
Butadiene, hexachloro
Ether, 4chlorophenyl
phenyl
Toluene, 2,4dinitro
Phenol, 2,4dichloro
Phenol, 2,4dinitro
Phthalate, diethyl
Phthalate, Bis(2ethyl
hexyl)
Acenaphthylene
Benzo(a)pyrene
Fish Pollutants
.(ti/2 >100h)
Aldrin
Heptachlor
PCB1260
Phenol, 2,4dinitro(?)
Phthalate, diethyl
Phthalate, Bis(2ethylhexyl)
Ben zo(a)pyrene
All of the assignments as air, water, and/or soil pollutants appear
reasonable in connection with the results of the Level 1 fugacity calcu
lations, and the known (or estimated) properties of these chemicals.
IV12

V. LEVEL II MACKAY CALCULATIONS
A. Basic Assumptions/Model Output
The Level II calculations go beyond the Level I equilibrium
calculations by allowing:
>, • .
1) Degradation (by firstorder kinetics only) in each subcompart
ment;
2) A net flux of the chemical into the total compartment; and
3) Removal of the chemical from a subcompartment by advection,
e.g., transport in the air or water.
The Level II calculations do not consider rates .of intercompartmental
transport via such pathways as runoff, washout or volatilization.
Equilibrium partitioning between the subcompartments (a dynamic steady
state) is allowed. All other aspects of the basic model, including the
concept of accessible volumes for a chemical in each subeompartment,
still remain.
The Level II calculations provide as output estimates of the
following:
1) The mass, M (mol), of the pollutant in each subcompartment;
2) The concentration, C (mol/m ) or C' (ppt), of the pollutant
in each subcompartment;
3) The rate of removal of the pollutant from each subcompartment,
R. (mol/yr), due to the combined action of degradation and
advection; and
Vl

4) The mean residence time, T (yr), for the pollutant in the
model environment.
B. Description of the Model Environment
The Level II calculations were, with one exception, carried out
for the same model environment used with the Level I calculations.
(See Section IIIB.) The exception involves the elimination of
the Suspended Sediments and Biota subcompartments. Their elimination
does not materially affect the predicted concentrations for the remaining
subcompartments (air, water, sediments, soil) since their accessible
volumes are small. Elimination of the two subcompartments simplifies
the calculations but does not prohibit the model from estimating
pollutant concentrations in these subcompartments from the estimated
concentration in water.
As noted above, the Level II calculations can account for
advection, i.e., the net loss of a chemical due to transportin air,. .
water or sediment. The rate of loss due to advection must be calculated
with some assumed fluid transport velocities (e.g., air speed, current
speed) for the appropriate subcompartment. Examples of Level II
calculations with and without advection were provided in Subsection E
below. The additional Level II calculations reported in Subsection F
have all assumed that no advection losses take place.
C. ChemicalSpecific Parameters Required
For the level II calculations described below, the following
chemicalspecific input parameters are required:
3 " "
.1) Henry's Law constant, H (atm m /mol);
V2

2) Soil and sediment adsorption coefficient, K ;
oc
3) Molecular weight, MW (g/mol)
4) Firstorder rate constants, ki; (yr ), for all important
chemical, photochemical or biological degradation pathways,
by subcompartment; and
5) The rate ;of input of the chemical into the total compartment,
I (mol/yr).. : .
The bioconcentration factor for aquatic life, BCF, would have been
required if the Biota subcompartment had been kept in the model.
Values of H, K and MW were taken, when available, from a draft
report by SRI, International. Gaps were filled with estimates by
Arthur D. Little, Inc. Values of these parameters for the organic
priority pollutants were previously listed. (See Table 3.)
For the sample Level II calculations described below, a subset
of 24 chemicals from the full list of organic priority pollutants was
selected. Most of these chemicals have been (or are currently) the
subject of Risk Assessment studies by Arthur D. Little, Inc. for the
Environmental Protection Agency. The list of selected chemicals is
given in Table 11. ' . ;
•<
Table 11 also gives the values of the. degradation rate constants
used for each chemical. These values are mostly orderofmagnitude
estimates based upon data and discussions by Callahan e£ alU (1979),
Tabak (1980) and unpublished material prepared by SRI, International;
in risk assessment documents currently being prepared by Arthur D.
Little, Inc.; and in other miscellaneous sources. These values, while
considered reasonable, are for example purposes only. The shakeflask
V3

TABLE 11
—1 • a
FirstOrder Rate Constants (k, Years ) Used in Level II Calculations
No. Compound Biodegradation
Pesticides
7 • Chlordane
11. Dieldrin
17 . Heptachlor
20. TCDD
PCBs and Related Compounds
29. 2Chloronaphthalene
lUlosenated Aliphatics
36. Chloroform
39. Dichlorodifluoromethane
42. 1,2Dichloroethane
43. 1,1,1Trichloroethane
. 47. Chloroethene
50. Trichloroethylene
Halogenated Ethers
56. Bis(2chloronethyl)ether
57. Bis(2chloroethyl)ether
Monocyelic Aromattes
63. Benzene
65. 1,2Dichlorobenzene
'63. 1,2.4Trichlorobenzene
12. Toluene
Phenols and Cresols '
75 Phenol
77, 2,4Diehlorophenol
.79 Pentachlorophenol
81. 4Nitrophenol
Phthalate Esters
90. Bis (2rethylhexyl) phthalate
Polvcyclic Aromatic Hvdrocarbons
95; Benzo(ajanthracene
105. Naphthalene
0.03
0.2
0.1
0.03
3
1'
0
0.01
0.07
0
1
0
3
2
2
2
3
,
3
3
0.7
3
0.4
0.5
3
Photolysis'
Air ' Water
18
4.2
4.2
51
0.1
'i '
0.02
10
3
1000
63
26
1500
1000
84
250
400
2000
0
18
0
0
250
0
4.2
4.2
4.2
4.2
0.1
0
0
0
0 .
0
0
0
0
0
0
0
0
63
0
14
84
0
1900
250
Hydrolysis
0.1
0.2
260
0
0
' ' 0.6
0
0
1.4
0.07
0.8
10S
1
0
0
0
0
•o
0
0
0
•
10 ""
0
0
Oxidation
0
0
0
0
0.1
0
0
0
0
0
2.8
0
0
0
0
0
0
63
. 0
0
0
0
160
8.4
The values given for race constants are mostly order*ofmagnitude estimates based upon data and discussions
by Callahan, et al. (1979), Tatmk (1980), unpublished material prepared by SRI International, risk assess
ment documents currently being prepared by Arthur D. tittle. Inc.. and other miscellaneous sources. These
values, while considered to be reasonable, are Cor example purposes only.
b. Blodegradation rate constants were, in many cases, taken to be about one twentieth of (he rate measured
in seeded tests.
c. Photolysis is taken here to include any lightinduced reaction, including reaction with hydroxyl radicals
in Che atmosphere.
V4

biodegradation data of Tabak (1980) were especially useful in selecting
biodegradation rate constants. In many cases, a firstorder degradation
rate was taken to be 0.05 times the initial rate measured in these
seeded tests.
As shown in Table 12, certain degradation rate constants were
assumed to be applicable to 'two or more subcompartments. Thus, the
biodegradation rate constant (k ) for a chemical was always assumed to
be applicable to the surface water, sediment and soil subcompartments.
Similarly, the rate of hydrolysis (k ) was assumed to be the same in
u
these three subcompartments, while the rate of oxidation in water (kn)
was cut in half for the sediment and soil subcompartments. Biodegradation
hydrolysis and oxidation (excluding lightinduced freeradical oxidation)
were not allowed in the air subcompartment. Lightinduced degradation
was limited to the air and surface water subcompartments.
The estimated flux of each chemical into the model environment,
I (mol/yr), was derived whenever possible from emissions estimates
provided in the risk analysis documents (being prepared by Arthur D.
Little, Inc.), from preliminary estimates provided by Acurex, Inc., or
from other inhouse reports. If these reports provided an estimate of
the total annual losses to the environment (to air, water and land) in
the U.S., that figure (in kg/yr) was divided by the area of the 48
ft 9 f 9
contiguous states (7.86 x 10 km ) to obtain a flux  in kg/km yr  for
2 ' •
our model environment which has a surface area of 1 km . Dividing this
flux by the molecular weight (kg/mol) provides the value of I in the
desired units (mol/yr). No emissions estimates were available for 5 of
the 24 compounds in the test set; reasonable default values were selected
for these chemicals. The values of I for each test chemical is provided
below with the discussion in Section F.
V5

TABLE 12
Scheme for Assignment of Rate Constants for Level II Calculations
Phase
f Air
Surface Water
Sediment
Soil
Degradation Process
Photodegradation
Biodegradation Air Water " Hydrolysis Oxidation
0 kp 0 00
a
kB ° kP ^ kO
w
k_ 0 0 k_ 0.5k.
D n U
k 0 0 lc^ .0.5k
o n U

D. Level II Equations . •
The basic tenets of the fugacity approach used for Level I (see
Section III) are also valid for the Level II calculations. Most of the
parameters used were previously defined along with the Level I descrip
tion. A summary list is provided below: ;
subscript i = compartment identifier (For sample calculations given
here: 1 ~ air, 2 = surface water, 3 = sediments,
4 = soil)
3 • •
C. = pollutant concentration (mol/m )
Cf * pollutant concentration (ppt in v/v for air and w/w for
water, sediments and soil)
c = "concentration" of sediments or soil in their respective
N i 3
' subcompartments (g/m ) •
f = pollutant's fugacity (atm)
3
H » Henry's Law constant (atm m /mol)
I = flux of pollutant into model environment (mol/yr)
k( ) = first order rate constant for degradation; k for
biodegradation, k for hydrolysis, etc. (yr~^)
K. = overall firstorder degradation' constant for each
subcompartment (yr ). Obtained from sum of individual
k. . values and  if desired  advection rate constants.
K = soil or sediment adsorption coefficient based on organic
oc
carbon content

M. = mass of pollutant in each subcompartment (mol)
MW « pollutant's molecular weight (g/mol)
(oc). = organic carbon content of sediments or soil
R = gas constant
R, » rate of removal of pollutant in each subcompartment
(raol/yr)
T = temperature (K)
T = mean residence time of pollutant in model environment (yr)
3
V = accessible volume of each subcompartment (m )
Z = fugacity coefficient of pollutant in each subcompartment
3
(mol/m a tin)
A good narrative discussion of the Level II calculations is
provided in the original article by Mackay (1979). The detailed
instructions provided below follow his basic instructions with few
modifications.
StepbyStep Instructions
(1) For the pollutant of interest, obtain MW, H, K ,1 and k, ,
(the individual degradation rate constants). {It is helpful to
set up a matrix, such as the one shown in Table 12, for listing the
selected values of k, . for each subcompartment.]
(2) For the model environment, determine the desired values of V ,
c and (oc).. [The values used here for the test set are shown
si i
V8

in Table 13.] . ... , 
(3) Determine, for eachsubcompartment, the total firstorder rate
constant for degradation (plus advection if desired) by summing
the appropriate k, y.values: .
K ' Z k . .. (34)
;
[The summations used for our test set are shown in Table 13.] All
k., v values, and thus K., must be in units of yr .
(4) Determine, for each subcompartment, the value of the fugacity
coefficient, Z (mol/m ), using the equations given previously
for the Level I calculations: equations 3, 4, 8 and 12 [in
Section III] for the air, water, sediments and soil subcompart
ments, respectively. [These equations are also provided in Table
13.] . .
(5) Calculate the fugacity of the pollutant, f (atm), from:
f  I/I V Z K ' . (35)
± l l i •
(6) Calculate the mass of the pollutant in each subcompartment, M ,
from:
Mi * fZiVi
and then calculate the total amount of the pollutant in the model
environment from £ M.. . ,
i ' '."..
(7) Calculate the concentration of the pollutant in each subcompart
ment with:
C± (mol/m3) = Z}f = M±/V1 ,. (37)
V9

TABLE 13 .
Summary of CompartmentSpecific Equations and Parameters for Level II Calculations
f
i Phase
1 Air
2 Surface Water
. 3 Sediments
4 Soil
KjXyr""1) V1(m3) Z^mol/m3 atm)
k 1010 1/RT(=41.6 at 20°C)
a
kB = kp + 1^ + ^ 15 x 105 1/H
w
k_ + Ic, + 0.5k_ 5 x 103 10"8(oc),K c /H
o H 0 3 oc s_
(=0. 2K /H)3
oc
kB + 1^ + 0.5k0 1.4 x 105 10~8(oc)4KocCs /H
(=0.04K c/H)b
C^(ppt)
2.4^ (v/v)°
(MW)M2/0.15 (w/w)
(MW)M 100 (w/w)
(MW)M4/0.28 (w/w)
•
a. Assumes (Oc) = 10%, c = 2 x 10 g/m
3 si
/: 3
b. Assumes (oc)  2%, c = 2 x 10 g/m
4 S4
c. (v/v) = volume to volume ratio
d. (w/w) = weight to weight ratio

If concentrations, C', in units of ppt (v/v for air and w/w for
the other subcompartments) are desired, the equations given
previously for the Level I calculations may be used: equations
24, 25, 27, and 29 [in Section III] for the air, water, sediment
and soil subcompartments, respectively. [These equations are also
provided in Table 13. ]
(8) Calculate the rate of removal of the pollutant from each subcompart
ment from:
Rt (mol/yr) = V^K = f V Z±K (38)
(9) Calculate the average residence time of the pollutant in the model
environment from:,
T (yr) = Z M../I " . (39)
E. Level II Calculations, with Advection,for One Chemical
Level II calculations, with the consideration of advection, were
carried out for tetrachloroethylene. The simple fourcompartment model
described above was used. The firstorder.rate constants used are shown
in Table 14 and Table 15 shows some of the intermediate parameters, that
must be calculated; values are shown for two casest with and without
advection.
For the case with advection it was assumed that: .(1) the air
compartment was constantly swept.with a wind whose velocity was 16 km/hr;
(2) the water compartment was a river, 50m wide, 3m deep, with a. current
of 3.2 km/hr. In both cases a steadystate input of 200 mol/yr was
assumed. • . '•••_,
The final results of the Level II calculations are shown in Table
16. The calculated values for "total removal rate"(V C.K ) show .that
Vll

TABLE 14
FirstOrder Rate Constants for Tetrachloroethylene (Years'1)'
Phase Biodegradation Photolysis
la. Tetrachloroethylene (no advection)
Air 0 50.6
Water 1 1
Sediment 1 0
Soil 1 0
Ib. Tetrachloroethylene (with advection)
Air 0 50.6
Water 1 1
Sediment 1 0
Soil 1 0
Hydrolysis Oxidation
0 0
0.1 1
0.1 0.5
0.1 0.5
0 0
0.1 1
0.1 0.5
0.1 0.5
Advection Total
0 50.6
0 3.1
0 1.6
0 1.6
.
1.04 x 105 1.04 x 105
2.80 x 104 2.80 x 104
0 1.6
0 1.6
a. The values given here for the rate constants are mostly orderofmagnitude estimates based upon
data and discussions from Callahan e£ al. (1979) and  to a much lesser extent  a few other
sources. These values, while considered to be reasonable, are for example purposes only.
b. Photolysis is taken here to includeany lightinduced reaction, including reaction with hydroxyl
radicals in the atmosphere.

TABLE 15
Level' II Calculations for Tetrachloroethylene.'. Intermediate
Parameters3
/ mol \ Vi
1 3 I 3
Phase \ m *atm ' (m )
Air 41.6 1010
c.
Water 50 1.5 x 103
•\
Sediment 3600 5 x 10
5
Soil 720 1.4 x 10
/
K ' . . ZiViKi
• / mo], \
(yr ) * atmyr '
50.6 2.10 x 1013
(1.04 x 105)3 (4.33 x lO16)8
7
3.1 2.33 x W'
(2.80.x 104)3 (2.10 x 1011)3
7
1.6 2.88 x 10
8
1.6 1.62 x 10
1 1
E  2.10 x 10XJ
16 (
(= 4.33 x 10 )
a. For K ' and Z V K., two values are given. The top number is for the
case involving no advection. The bottom number, in parenthesis,
involves advection associated with the air and water subcompartments.
V13

TABLE 16
Final Results of Level II Calculations for Tetrachloroethylene
a,b,c
Phase
Air
Water
Sediment
Soil
Mi
(mol)
3.96
(1.9 x 10 ~3)
7.1 x 10~5
(3.5 x 10"8)
1. 7 x 10~4
(8.3 x 10~8)
9.6 x 10~4
(4.7 x 10"7)
S » 3.96
(3.1 x 10~3)
(ppt), .
9.5
(4.6 x 10~3)
7.9 x 10~2
(3.8 x 10~5)
2.8..
(1.4 x 10~3)
0.57
(2.8 x 10~4)
Wi
(mol/yr)
200
(200)
2.2 x 10~4
" (9.7 x 10~4)
2.7 x 10~4
(1.4 x 10~7)
1.5 x 10~3
(7.4 x 10~7)
a. M  B mass of chemical in each subcompartment;
CT = concentration of chemical in each subcompartment. Units.
are (vol/vol) for air and (wt/wt) for other subcompartments.
V.C K •« total removal rate from subcompartment.
b. Two values are given for each parameter. The top number is for the
case involving no advection. The bottom number, in parenthesis,
involves advection associated with the air and water subcompartments.
c. Steadystate input (I) of 200 moles/yr assumed in both cases.
V14

degradation in the atmosphere is, by far, the most important fate path
way for this chemical.
F. Level II Calculations for Test Set (Ko Advection)
Level II calculations were carried out for the teat set of 24 4
chemicals listed in Table 11. This table also shows the values of the
degradation rate constants used. No advection out of the model
environment was allowed.
The results of the calculations are given in,Table 17. This table
also provides the values for the other chemicalspecific input parameters
required (MW, H, K , X) and the values of some of the intermediate
parameters (f, K , Z , and V Z.K ). It should be noted that the primary
outputs  M., C' and R.  are all directly proportional to the input
flux, I. Thus, adjustment of the primary outputs is easy if a different
value of I is selected. • •
Some of the model outputs, in particular the values of T (residence
time) and G' (subcompartment concentrations), are displayed in Figures
25 so that the relative position of the various chemicals can be seen.
Predicted values of T are seen .(Fig. 2) to vary over five orders .of
magnitude, from 50 years for dichlorodifluoromethane (a stratospheric
pollutant) to 0.25d for bis(2chlorbethyl)ether; When model" calculations
for specific chemicals are being run this residence time should be con
sidered as an important factor in setting the accessible volumes (V ) of
each subcompartment. If, for example, a preliminary calculation shows
T s Id and degradation in the atmosphere is important (i.e., R is large
in comparison with R , R and R ), then the accessible volume for the air
compartment (V ) should probably be reduced in a second (revised)
calculation. A height of 1 km (rather than the 10 km used for the test
set here) would be more appropriate.
(Text continues on page V26)
V15

TABLE 17
Results of Level II Calculations for Test Set
f
h*
7. Chlordane
Inputs MH  406
K  1.66 x
oc
Outputs
 *—
£ « 3.43 x 10"13 atm
i  1
Air
K. » 18
. i
Zt ' 41.6
ViZlKi • 749 x IO12
M±  0.143
C^ • 0.343
Rt  2.57
, H  9.4 x 10"5 atm m3/mol
IO3 I • 3. 1 mol/yr
EMt  4.14 mol T  1.3 yr
2 3
Water Sediment
18.1 0.13
1.06 x 10* 3.53 x IO8
2.88 x IO10 2.30 x IO11
5.45 x 10~* 0.606
•
1.48 2.46 x 10*
1 *}
9.88 x 10"J 7.89 x 10"*4
4
Soil
0.13
7.06 x IO7
1.28 x IO12
3.39
4.92 x IO3
0.439
11. Dieldrin
Inputs MW  381
K  1.91 x
oc
Outputs
f  2.63 x 10"18 atm
i  1
Air
K, » 4.2
i
2t = 41.6
V,ZK.,  1.75 x IO12
i i i ,.
M.  1.10 x 10
1 ,
C^ « 2.64 x 10"°
Rt • 4.60 x 10~6
.. H  4.57 x 10~10 atm n3/mol
10 I * 3.3 x 10 mol/yr
^  7.35 x
2
Water
4.6
2.19 x IO9
1.51 x IO15
8.65 x IO"4
2.20
3.97 x IO"3
10"2 nol T  2.2
3
Seditttsnt
0.4
8.36 x IO11 1
1.67 x IO15 9
1.10 x 10 "2 6
419
4.39 x IO*3 2
yr
4
Soil
0.4
.67 x
.35 x
.16 x
83.8
.46 x
io11
IO15
1C'2
io2
17. Heptachlor
20. TCDD
Inputs
,MH  373.5
K  1.41 x
oc
. H  3.95 x
10* I 
10 ~ atm m /mol
0.31 mol/yr
Outputs
£  3.
i
K.
i
Z.
i
V.Z.K.
i i i
M.
i
c<
i
Ri
93 x 10"14 atm
1
Air
4.2
41.6
 1.75 x IO12
 1.63 x 10~Z
<•' ">
 3.91 x 10 *
 6.88 x 10"2
Hl^ " 0.0172 mol T  5.5 x 10"2
2
Water
264
253
. 1.00 x IO10
1.49 x 10"6
3.71 x 10~3
3.93 x 10"4
3
Sediment
260
7V14 x 10S 1.
9.28 x IO11 5.
1.40 x 10"4 7.
5.23
3.65 x 10~2
yr (» 20d)
4
Soil
260
43 x IO5
20 x IO12
87 x 10"4
*"
1.05
0.204
Inputs
MW  322
K  3.80 x
oc
, H  1.3 x 10"^ atm m3/mol
10° I = 5.1 x 10" mol/yr
Outputs
t  2.
i
K.
i
Z.
i
V_Z,K,
i i i
M,
i
cr
i
34 x 10" atm
«• 1
Air
51
41.6
• 2.12 x IO13
 9.73 x 10~9
• 2.34 x 10~8
• 4.96 x 10 ~
EM  4.61 x 10"7 ool T  0.
2 3
. Water Sediment
4.23 0.03
769 5.85 x IO8
4.88 x IO8 8.78 x IO10
2.70 x 10~12 6.84 x 10~8
9 3
5.80 x 10 2.20 x 10
1.14 x 10'11 2.06 x 10"9
90 yr
4
Soil
0.03
1.17 x IO8
4.91 x IO11
3.83 x 10~7
<_A
4.41 x 10
1.15 x 10"8

TABLE 17 (cont.)
f
29. 2Chloronaphthalene
Inputs MW  162.6
K 5.5 x 103
oc
Outputs
f  1.72 x 10~13 atm ZM
, i  1
Air
Ki * O1
Zj  41.6
V.Z.K. » 4.16 x 1010 4.
ill «
Mt  7.14 x 10 Z 2.
C* • 0.171 2.
R± " 7.16 x 10"3 6.
39. Dichlorodifluorome thane
, Inputs MW =120.9
V661
Outputs
£  1.20 x 10 atm EM.
" 1  1
Air
. K£  0.02
2. ' 41.6
i q
ViZiKi " 8'3 * 10
M,  5010 6.
4
C'i  1.20 x 10
&t » 99.6
H  1.2 x 10"3 atm m3/mol
I  2.3 x 10" mol/yr
 7.66 x 10~2 ooi T = 3.3 yr
234
Water Sediment Soil
3.2 3.05 3.05
833 .9.17 x 105 1.83 x 105
00 x 108 T.40 x 1010 7.81 x 1010
14 x 10"5 7.86 x 10"4 .4.39 x 10"3
32 x 10~2 12.8 2.55
88 x 10~5 2.41 x 10"3 1.34 x 10~2
H  2.98 atm m3/mol
I  100 mol/yr '".
,
• 5010 mol T  50 yr.
; 2 3 4
Water Sediment Soil
000
0.336 4.44 0.887
0 0 0
07 x 10~4 2.68 x 10~* 1.50 x 10~3
0.489 3.24 0.646
000
36. Chloroform
Inputs MW <• 119.4 H  2.88 x 10~3 atm m3/mol
K  50.2 I " 21 mol/yr
oc
Outputs
f  1.68 x 10 ~U atm TM±  6.99 mol T  0.33 yr
i  1 2 3 4
Air Water Sediment Soil
K. » 3 1.6 1.6 1.6
i ,
Zt  41.6 347 3.49 x 10J 697
ViZiKi " 1>2S x 1()12 8'33 x 10? 2>79 x 10? lw56 x l°8
M.  6.99 8.74 x 10~4 2.93 x 10"4 1.64 x 10~3
i
c;  16.8 0.696 3.50 0.699
1 3 4 3
R±  21.0 1.40 x 10 4.69 x 10 2.62 x 10
42. 1.2Dtchlo roe thane
•Inputs MW  ,99.0 H  9.14 x 10"4 atm m3/mol
KOC 16.6 I = 86 mol/yr
Outputs . .
f  2.07 x 10~ 1 atm EM = 8.60 mol T  0.10 yr
1=1 2 3 i
Air Water Sediment Soil
Kt « 10 0.01 0.01 0.01
Z±  41.6 1.09 x 103 3.63 x 103 7.26 x 102
V1Z1K1 " 4>l6 x lo12 1'64 * l°6 182 xlO5 1.02 x 106
Mt  8.60 3.38 x 10~3 3.75X10"4 2.10xlO~:
' ci ' 206 223 3.71 0.743
Rt " 86.1 3.40 x 10"5 3.77 x 10~6 2.11 x 10~:

TABLE 17 (cont.)
f
M
00
43. 1,1,1Trichloroe thane
Inputs MW = 133.4
Koc 17A
Outputs
£ » 1.92 x 10~10 atm
i  1
Air
K.  3
i
Zt  41.6
V.Z.K.  1.25 x 1012
i i i
M, = 79.9
i
c;  192
i
Rt  240
50. Trichloroethylene
Inputs MW • 131.4
If » 38.0
oc
Outputs
f  3.70 x 10~12 atm
i  1
Air
KI " 63
Z » 41.6
V.Z.K, = 2.62 x 1013
ill
M,  1;54
i
c;  3.70
i
R  96.9
H » 3.0 x 10~ atm ID /mol
I  240 mol/yr
EM  79.9 mol T  0.33 yr
2 3
Water Sediment
1.47 1.47
33.3 1.16 x 103
7.34 x 106 . 8.53 x 106
9.59 x 10~4 1.11 x 10 ~3
0.853 14.8
1.41 x 10~3 1.64 x 10"3
4
Soil
1.47
232
4.78 x 107
6.24 x 10~3
2.97
9.18 x 10*3
47. Chloroethene
Inputs MW  62.5
K 9.34
oc
Outputs
f  4.81 x 10~13 atm
i  1
Air
Kt « 1000
Z± » 41.6
ViZiKi " A'16 * 1<)14
M  0.200
*•
CJ  0.480
tL±  200
K » 198 atm m /mol
I  200 mol/yr
ZMt • 0.200 mol
2
Water
0.07
5.05 x 10~3
, 53.0
3.64 x 10~10
_7
1.52 x 10
2.55 x 10~11
T  1.0 X 10
3
Sediment
0.07
9.43 x 10 ~3
3.30
2.27 x 10~U
—7
1.42 x 10 '
1.59 x 10~12
~3 yr (» 0.36d)
4
Soil
0.07
1.89 x 10"3
18.5
1.27 x 1010
—ft
2.84 x 10 °
8.90 x 10"12
56. Bis(2chloromethyl)ether
H » 9.10 x 10~3 atm m3/nol
I  97 raol/yr
EMt = 1.54 mol T  1.59 x
2 3
Water Sediment
4.6 3.2
110 835
7.59 x 107 1.34 x 107
6.11 x 10~5 1.55 x 10r5
5.35 x 10"2 0.204
2.81 x 10~4 4.96 x 10~5
10~2 yr (5.8d)
4
Soil
3.2
167
7.48 x 107
8.66 x 10 ~5
4.06 x 10~2
2.77 x 10"4
Inputs MW  115
K » 1.32
oc
Outputs
f  1.27 x 10~18 atm
i = 1
Air
Kt » 26
Z  41.6
V.Z.K.  1.08 x 1013
7
M.  5.30 x 10 '
1 c
C^  1.27 x 10
Rt  1.37 x 10~5
H  2.1 x lO^atm m3/mol
I  (1.1 x
EM1 » 5. 30 x 10
2
Water
1 x 105
4.76 x 103
7.14 x 1013
9.10 x 10"10
6.98 x 10~7
9.07 x 10~5
10 mol/yr]
~7 mol T  4,
3
Sediment
IxlO5
1.26 x 103
6.3 x 1011
8.03 x 10~12
9.24 x 10~8
8.00 x 10~7
.8 x 10"3 yr (1.8d
4
Soil
1 x 105
251
3.51 x 1012
4.48 x 10"11
1.84 x 10~8
4.46 x 10~6

TABLE 17 (cont.)
[57. Bis(2chloroethyl)ether
Inputs MW  143 . H  1.3 x 10*5, ato m3/mol
KO<; 15.9 . I  [8.9 x 10"* mol/yr]
63. Benzene
yr (»0.25d)
i • 1
Air .
2
Water
K±  1500
Z±  41.6
V.Z.K.  6.24
jL X i
. M±  5.93
C'  142
J_
S. • 8.92
1
M
x 10
x.10
x 10
x 10
14
7
6
4
7.
A.
1.
1.
6.
69
61
64
56
59
4
x IO4
xlO10
X108
xlO5
xW8
3
Sediment
2.
4.
1.
2.
7.
45
90
75
50
01
4
xlO5
x 10
x 10
x 10
x 10
9
9
5
9
4.
2.
9.
4.
3.
4
Soil
4
89 x IO4
74 xlO10
76 x 10"
99 x 10
92 x 10
^
65. 1.2Dlchlorobenzene
Inputs MW " 147.0 ,
K 2.00 x 10J
oc . •
H  1.93 x 10"3 atm m3/mol
I  5.9 x 10~J mol/yr
Outputs
f « 1.69 x
i »'
10~16 atm
1
.Air
84
41.6
EM  7.03 x 10
2
Water
*5
T  1.2
Sediment
10~2 yr (»4.3d)
4
Soil
VJZ.K. • 3.49 x 10
"ii"!
Mi
' Ci
7.03 x 10
1.69 x 10
,13
5
4
5.90 x 10
3
2
518
1.55 x 10'
1.31 x 10"
1.28 x 10"
2.62 x 10
8
~8
2.07 x 10
2.07 x IO9
1.75 x 10
2.57 x 10
3.50 x 10
2
4.14 x
IO
,?
3
7
1.16 x 10
9.80 x 10"
5.14 x 10"
1.96 x 10"
10
Inputs MW « 78.1
K • 74 2
Koc '*'
Outputs
f  2.07 x 10~12 atm EM±
i  1
Air
K.  1000
i
Z.  41.6
1 14
V.Z.K. » 4.16 x 10 5
i i i
M,  0.860 5
1
c;  2.06 2
i
Rt  860 1
68. 1,2,4Trichlorobenzerie
. Inputs MW '" 181.4 ,
. K  1.02 x 10 '
oc
Outputs
£ = 9.62 x IO"14 atm m±
~ i  1
Air
K.  250
i
Z±  41.6
V.Z.K,,  1.04 x IO14 1
i 1. i.
Mj  4.00 x 10~2 6
• C.'  9.6 x 10~2 7
i
R  10.0 1
_•» i
H  5.5 x 10 "" atra m"/mol
I  860
 0.86 mol
2
Water
2
182
.46 x IO7
.64 x 10~5
.94 x 10"2
.13 x 10"4
H  2.31 x
I  10
 4.28 x 10
2
Water
2
433
. 30 x IO8
.24 x 10~6
.55 x 10"3
.25 x IO*5
mol/yr
T  1.0 X 10
3
Sediment
2
2.70 x IO3
2.7 x IO7
2.79 x 10"5
0.218
5.59 x 10"'
IO"3 atm m3/mol
mol/yr
mpl T » 4.
3
Sediment
2
8.83 x IO5
8.83 x IO9
4.24 x 10"4
7.69
8.49 x 10"4
"3 yr (0.36d) •
4
Soil
2
540
1.51 x IO8
1.56 x 10~4
4.36 x IO"2
3.13 x IO"4
3 x 10~3 yr,(l'6d)
4
Soil
2
1.77 x IO5
4.94 x IO10
2.38 x 10"3
1.54
4.75 x 10~3

TABLE 17 (cont.)
f
ISJ
O
72. Toluene
Inputs tW
Soc
Outputs
f  3.55 x
i 
K "
i
Zi
Wi.*
rl » ™ A »
ci  3
R. 
i
 92.1
 339
1014 atm
1
Air
400
41.6
ML
66 x 10
48 x 10~2
55 x 10 ~2
5,89
75. Phenol
H * 5.17 x 10~3 atm nfVraol
I  5.9 mol/yr Inputs MB  94.1
Outputs
EM,  1.48 x 10~2 mol t  2.5 x 10~3 yr <0.92d) 14
i f  2.94 x 10 atm
2
Water
3
193
7
8.68 x 10 '
1.03 x 10r6
6.32 x 10"4
_&
3.08 x 10
3
Sediment
3
A
1.31 x 10
a
1.96 x 10
2.33 x 10~6
2.15 x 10 ~2
6
6.96 x 10 D
4
Soil
3
3
2.62 x 10
g
1.10 x 10*
1.30 x 10~5
4.29 x 10~3
_5
3.90 x 10
77. 2,4Dichlorophenol
Inputs MW
= 163
K  437
oc
Outputs
f * 1.05 x
i =•
K, "
i
Z. •
i
V,Z K,, 
i i i
M4 •= 4.
1
c; • i.
i
Ri =
10~14 atm
1
Air
0
41.6
0
.35 x 10~3
_9
.04 x 10
0
H = 2.8 x
I = 3.4 x
, „$ 3 ,
10 " atm m /mol
10~2 mol/yr
£M± • 1.57 x 10~2 mol T  0
2
Water
3
3.57 x 105
1.61 x 1011
5.60 x 10"4
0.608
1.69 x 10~3
3
Sediment
3
3.12 x 107
4.68 x 1011
1.63 x 10"3
26.6
4.91 x 10~3
.46 yr
4
Soil
3
6.24 x 106
2.62 x 1012
9.14 x 10~3
5.32
2.75 x 10~2
i  1
Air
K,  . 2000
.. i
Z,  41.6
1 14
V.Z.K.  8.32 x 10
111 n
M.  1.22 x 10
c;  2.93 x 10~2
1
R  24.5
79. Pentachlorophenol
Inputs KM  266.4
K  6.03 x
oc
Outputs
f  6.68 x 10 ~15 atm
i • 1
Air
K±  18
Zt  41.6
viZiKi " 7*49 * 1()12
M.  2.78 x 10~3
3
CJ • 6.67 x 10
R. = 5.00 x 10~2
•
H  4. 54 x 10~7 atm m3/mol
I  26 mol/yr
EM1  2. 89 x 10~2 mol t  1.1 x 10~3 yr (0.40d)
2
Water
129
2.20 x 106
4.26 x 1013
9.72 x 10~3
6.10
1.25
3
Sediment
35
7.14 x 106
1.25 x 1012
1.05 x 10~3
9.88
2
3.68 x 10
4
Soil
35
1.43 x 106
6.99 x 1012
5.90 x 10~3
1.98
0.206
, H = 2. 8 x 10 atm m /mol
10 I  0.72
T.M±  0.952 mol
2
Water
14.7
3.57 x 105
7.87 x.1011
3.58 x 10~A
0.636
5.26 x 10~3
mol/yr
t « 1.3 yr
3
Sediment
0.7
4.31 x 109
1.51 x 1013
0.144
•j
3.84 x 10
0.101
4
Soil
0.7
8.61 x 108
8.44 x 1013
0.805
766
0.564

TABLE 17 (cont.)
,81. 4Nitrophenol
oc
139.1
51'3
f  2.40 x 10"18 atm
1
Air
0
41.6
Wi
M±  9.99 x 10
c;  2.40 x 10"
7
90. Bi8(2ethylhexyl)phthalate
H  3. 7 K 10*11
I  (0.91 mol/yr]
Ij  3.17 x
. 2
Water
87
2.70 x IO10
3.52 x 1017
9.72 x 10" 3
9.01
0. 845
10~2 mol T 
3
Sediment
3
2.77 x IO11
4.16 x 1015
3.32 x 10~3
46.2
9.98 x 10~3
3.5 x 10~2 yr
4
Soil
3
5.55 x 1010
2.33x 1016
1.87 x 10"2
9.27
5.59 x 10~2
yr <=>13d)
 391
H » 3.0 x 10~7 atm m3/mol
K • 2.24 x 10
oc
Out
f 
V.Z
i
puts
2.80 x
i 
K, •
i
Z. 
i
^ *
i i
M,  1.
i
c;  2.
i
R, "
10~1(? atm
1
Air
0
41.6
0
6
16 x 10 ^
78 x 10'6
0
' I " 55
EM  138
2
Water
0.4
3.33 x IO6
2.00 x 10U
f.
1.40 x 10^
3.65 x 10~3
5.60 x 10~7
mol/yr
T » 2.5 yr
3
Sediraeat
0.4
1.49 x 101S
2.98 x 1018
20.8
8.13 x IO5
8.34
4
Soil
0.4
2.99 x 10U
1.67 x IO19
117
1.6 x IO5
46.8
95. • Ben2o[a]anthraccne
. Inputs MW « 228.3 .
K  2.24 x IO5
4.68 x 10~20 atm
H  1.0 x 10
I  [5.57 x 10"
i 
Ki"
zi
viziKi 
Mi
ci
Ri"
i.
i.
4.
4.
1
Air
250
41.6
04 x
95 x
68 x
87 x
10,"
io8
Kf8
io6
EM " 6.92 x 10~5 nol
105. Naohthalene
ol/y]
t  1.2 x IO"2 yr <4.5d)
2
Water
Sediment
2060
1.00 x 10
3.09x 10
7.02 x 10"
1.07 x 10"
,6
.14
80.5
4.48 x 10
.10
1.80 x 10
1.05 x 10"
0.240
,16
4
Soil
80.5:
8.96 x 10s
1.01 x 10
5.87 x 10"
4.79 x 10"
.17
Inputs MW  128.2
K  1.07 x IQ
OC
H  4.6 x iO
I » [9.92
atm m /mol
mol/yr]
1.45xlO'5 8.42 x 10~* 4.73x10"
Outputs
£  5.07 x
i 
K,. •
i
Z 
 i
V Z K 
i i i
M. »
i
C' 
vl
R, *
Uf"
1
Air
0
41.6
0
21.1
50.6
0
EM1 • 21.9 mol
2
Water
261
2.17 x IO3
8.50 x IO10
1.65 x 10~2
14.1
4.31
T  2.2 yr
3
Sediment
7.2
4.65 x IO5
1.67 xlO10
" 0.118
1.51 x IO3
0.847
4
Soil
7.2
9.30 x 10*
9.38 x IO10
0.661
302
4.76

RESIDENCE 102_.
TIME(yeors)
10 
2Chloronophtholene *.^^
Pcntochlorophcnol ' ^
1 
2,4Dichlorophenol '\__tol
10"'
Dichlorodifluoromethone
Bis(2ethylhexyl)phtholate
Dieldrin
Chlordane
TCDD
Chloroform
1, 2Dichloroethane
4Nitrophenol
1,2Dichlorobenzene
Benzo [a] anthracene
1,2,4 Trichlorobenzene
Phenol
Chloroethene
Benzene
FIGURE 2. ESTIMATED RESIDENCE TIME IN COMPARTMENT
FROM LEVEL n CALCULATIONS (No Advection).
V22

CONCENTRATION IN in,
WATER (ppt) 10
10 
1 
Chloroform ;*
Pentochlorophenol ~r~//
Drchlorodifluoromethane ' .Qj_
10'2
Hftotnr hinr —• • »
ID"3
to'4
10'5
r T 106
io7
10'8
* Position of chemicals listed in
brackets very uncertain. Based
on use of default value for input (I).
in"*
[Naphthalene]*
[4Nitrophenol]
1,2 Dichloroethone
Chlordone
1,1,1Trichloroethane
2,4Oichlorophenol
Trichloroethylene
2 Chloronaphthalene
1,2,4Trichlorobezene
Bis(2ethylhexyl}pntna!ate
CBis(2chloroethyl) ether]
[Benzo[a]anthracene]
1,2Dichlorobenzene
Chloroethene
TCDD
FIGURE 3. ESTIMATED CONCENTRATION JN WATER COMPARTMENT
FROM LEVEL H CALCULATIONS (No Advectioo).
V23

IN AIR, ppt (w/v) 1U ~
10.?,
^NQpnTnaicnej ^
10 
1 
^niorocTnenc ^
H^ntnrhlAr — •*
Phenol ^
10"2
>o3
to;5
Bis(2ethylheKyl)phthalote ss^
[4 Nitrophenol]— ^^
Position of chemicals listed in
brackets very uncertain. Based
on use of default value for input (I)
ifl~®—
t
^~

CONCENTRATION IN 106_
SEDIMENTS (ppt)
10*
104
103
102
1.1,1Trichloroethone ^, fc
to 
1,2Dichloroethane ^^S
Dichlorodifluoromethane ' 1 _
10'
io2
. . . io3
'..;•" • io4
of chemicals listed in
very uncertain. Based
>f default value for input (I) ^
io7
la \
•  \r '*
"*
"^—
i ~
^
Bis(2ethylhexyl) phthalate
Chlordane.
[Naphthalene]'
2,4Dichlorophenol
2Chtoronophthalcne
Heptachlor
Chloroform ' .
[Bento [a] anthracene]
Trichloroethylene
TCDD
[Bis(2chloroethyl)ether3 .
Chlorbethehe '•;"'•
[Bis (2chioromethyl )ether]
FIGURE 5. ESTIMATED CONCENTRATION IN SEDIMENT COMPARTMENT
FROM LEVEL tt CALCULATIONS (No Advecjion). '
" V25" \  .":

Predicted water compartment concentrations (Fig. 3) range over 10
orders of magnitude while those for air (Fig. 4) and sediments (Fig. 5)
range over 12 and 14 orders of magnitude, respectively. Predicted soil
concentrations are one fifth of the predicted sediment concentrations and
thus the soil concentration ranking would appear as shown in Figure 5.
The extremely high value of C' shown for bis(2ethylhexyl)phthalate in
Figure 5 results from the high (probably excessively so) value of K
n oc
used (2.2 x 10 ).
An alternate manner of presenting the predicted environmental con
centrations is shown in Figure 6. This figure plots  for each chemical 
predicted values of M (mass in air), M_ (mass in surface water), and
M, + M, (total of mass in soil and sediments), expressed as a percent
of the total mass in the model environment. This figure dramatizes the
(predicted) tendency of most of the selected priority pollutants to
reside primarily in the air compartment or thesoil/sediment compartments.
Only phenol (#75) has an appreciable mass ( ~34%) residing in the water
compartment; , '. • t
Predicted values for removal rates, R., show that atmospheric
degradation (mostly reaction with lightproduced hydroxyl radicals) is
the most important loss area for 14 of the 24 chemicals. For two
chemicals. 2,4nitrophenol and bis(2chloromethyl)ether  degradation
in the surface water compartment is the most important; and for the
remaining 8 test chemicals, the soil compartment was most important for
degradation. These results would be altered (perhaps significantly) if
different, adjustable, values of V were used and if advection was
considered.
G, Comparison of Predicted Concentrations with Monitoring Data
The environmental concentrations predicted by the Level II calcu
lations are compared in Table 18 with monitoring data for eight chemicals.
In most cases, monitoring data on surface water concentrations (much of
V26

57
36, 39, 42
43, 47, 50
56, 63,65, 72
to
Water
79, 90, 95
Soil and
Sediment
Note: Numbers by each point refer to the compounds listed in Table 11. The percent of the total mass
(in the model environment) in each of the three subcompartments is given by the vertical dis
tance from the line opposite the apex with the named subcompartment.
Pimipp 6 .PLOT.QF.D!STR!BUT!OKjRRED!GTEDiBYLSVEL!!,CALCULAT!ONS.
PERCENT IN AIR, WATER, OR SOIL AND SEDIMENT COMPARTMENT.

TABLE 18 .
Measured vs Environmental Concentrations for
Selected Chemicals3
No.
36.
39.
50.
51.
63.
75.
77.
79.
Compound
Chloroform
Dichlorodifluoromethane
Trichloroethylene
Tetrachloroethylene
Benzene
Phenol
2, 4Dichlorophenol
Pentachlorophenol
Approximate Concentration Ratio:
Measured/Predicted
Air
110
1021
1102
110
102103
—
—
—
Water
103104
103105
104(+102)
104107
104105
102104
'vlO4
. 1Q2~105
Data on measured concentrations were taken from risk assessment
documents being prepared by A.D. Little, Inc. Data clearly
labeled as representing sites near pollution sources were ex
cluded in an attempt to obtain "background" concentration data.
The predicted concentrations were, from the Level II (Mackay)
calculations.
V28

4 2
the data were from STORE!) indicate ambient levels that are 10 (+ 10 )
higher than the surface water concentrations predicted by the model.
Monitoring data for atmospheric concentrations (five chemicals) indicated
2
ambient concentrations are generally within a factor of 10 to 10 of the
Level II predictions reported here. Insufficient data were available to
make meaningful comparisons for the other chemicals in the test set or
for the soil and sediment compartments.
The wide discrepancies seen for the surface water concentrations
is thought to be due to the combined effects of:
1) A bias towards the more polluted streams and rivers in
monitoring programs; besides having higher than "average"
concentrations, chemical pollutants in these waters may
have been discharged to the water and not had time to
equilibrate with other environmental 'compartments;
2) Problems in obtaining meaningful "averages" of. concentration
data from monitoring programs when detection or reporting
levels are often not specified, when the concentrations being
reported are frequently near these detection limits, and when
data management systems (e.g., STORE!) use questionable
methods (e.g., using either 0 or the detection limit) when
averages must be taken from data sets containing numerous
"not detected" or "less than X" entries.
3) A bias towards less polluted areas in the method used here to
/ . *
select the inputs, I (mol/yr), for each chemical into the
model environment. The use of total U.S. emissions divided
by the area of the 48 contiguous states (to yield I in
2 2
mol/yr km for the model environment whose area was 1 km )
will significantly underestimate pollutant loadings for
chemicals released in the more populated and industrialized
sectors of the U.S. which occupy only a relatively small
fraction of its surface area.

The discrepancies seen, then, should not be considered a failure
on the part of the basic fugacity model, but a result of inadvertent
biases in the monitoring data and model parameters used. Both of these
biases can presumably be compensated for, if not fully corrected, in
future uses of this model.
V30

VI. LEVEL III MACKAY CALCULATIONS
A. Basic Assumptions/Model Output :
The Level III calculations go beyond the Level II calculations by
allowing:
1) A steady state flux, I> (mol/yr), of the pollutant into
any subcompartment, i;
2) Timedependent intercompartmental transfers (e.g., volatiliza
tion from water) where a steadystate transfer process may be
postulated.
Other processes covered in the Level II calculations (e.g., degradation
and advectiqn out of the model environment) may still be included.
The subcompartmentspecific pollutant loadings (I. values) will
frequently be available from materials balance studies for a pollutant.
These studies may provide estimates of (total) discharges to the sub
compartments of interest, i.e., air, surface water and land. This
model does not, however, simulate point source discharges. Thus,
a discharge to land, for example, would imply a discharge to all of
the land in the model environment chosen; the Level III calculations
r
will then assume that all of the land is equally contaminated. This
will — at least for discharges to land — seldom be a good assumption.
The intercompartmental transfers are postulated to occur as a
steadystate transfer rate, N (mol/yr), as:
N = D^C^  f..) (40)
VI1

where D.. is the transfer coefficient for transfer between subcompartments
± and j, and f. and f. are the fugacities of the pollutant in subcom
partments i and j, respectively. In this treatment, D = D and
J J*
values of D must always be positive. The transfer coefficient, D,
has units of mol/(yr atm) and will depend upon the pollutants rate
of diffusion and the common transfer area between the two subcompartments.
Mackay (op.cit.) has shown that for volatilization from water
D = KQa/RT (41)
where K is the overall gas mass transfer coefficient (m/yr), a is the
interfacial area between the surface water and atmosphere (m~), R is
the gas constant and T the temperature.
K_ is a chemical and environmentalspecific parameter which
may be estimated from the chemical's Henry's law constant and molecular
weight (Thomas, 1980). For compounds of relatively low molecular
weight (<65 g/mol) the equations given by Thomas (op.cit.) may be
combined to give the following expression:
K,,  87.6 [(0.314H + 7.86xlb~5)\/MWr1m/yr (42)
{j t . . • ; •
where MW is the molecular weight (g/mol), H is Henry's law constant
3
(atm m /mol), and a temperature of 20°C has been assumed. For compounds
of high molecular weight (>65 g/mol) the wind and current velocity,
and the mean depth of the water body, are also required for the
estimation of KG> The equations given by Thomas, for one set of wind
and current velocities and three depths, may be reduced to the
following:
• V wind = 5 m/s (VLO mph), V current = 0.5 m/s (yl mph),
Depth of water  1 M:
KG = 87.6 [(0.120H + 3.77xlO~5) VMW]"1 m/yr (43)
VI2

* Depth of water = 3m (velocities as above):
K = 87.6 [(0.057H + 3. 77xlO~5) VSW]^1 m/yr (44)
•
• Depth of water = 10 m (velocities as above):
87.6 [(0.025H + 3. 77xl(f5)VSw3~X m/yr (45)
Other intercompartmental transfer processes which may be
important for some pollutants are volatilization from soil, wet and
dry deposition (to land and surface waters), adsorption on and
desorption from sediments, and uptake and clearance by aquatic biota.
Expressions for the respective transfer coefficients for each of these
processes can presumably be devised. However, none are presented in
the Mackay work (op. cit.). Thus, for the present, the user must
make an informed guess for K_ for these other processes.
t» •
Implicit in this treatment of intercompartmental transfers
is the assumption that the rate of transfer (N in eq.40) is directly
proportional to the difference in the chemical's fugacity in the two
subcompartments. This will not always be true.
The Level III calculations provide as output estimates of the
following:
• '.. •' ' p 3 •''': ' '' ' '
1) The mass, M.(mol), and concentration, C (mol/m ) or
Cj (ppt) , of the pollutant in each subcompartment.
' 2) The rate of removal of the pollutant from each sub
compartment, R.(mol/yr), due to the combined action of
degradation, advection and intercompartmental transfer; and
3) The mean residence time, x (yr), for the pollutant in the
model environment.
The effect of intercompartmental transfers is also elucidated in the
calculational process.
VI3

B. Description of the Model Environment
The Level III sample calculation was carried out for the same
model environment used for the Level II calculations. (See Section V.)
Only the air, water, sediment and soil subcompartments are considered.
No advection out of the model environment is considered.
As noted in subsection A above, some exchange coefficients may
require compartmentspecific information. For volatilization from
water, for example, this includes: (1) the airwater interfacial
4 2
area (5 x 10 m in the model environment used here); and (2) for
chemicals with MW>65, the wind and current velocities and the mean
depth of the water. For the sample calculations given below we have
selected the conditions of equation 44, i.e., a wind velocity of
5 m/s, a water velocity of 0.5 m/s, and a mean water depth of 3 m,
C. ChemicalSpecific Parameters Required
For the Level III calculations described below, the following
chemicalspecific input parameters are required:
1) Henry's Law constant, H (atm m /mol) ;
2) Soil and sediment adsorption coefficient, K ;
oc
3) Molecular Weight, MW (g/mol);
4) Firstorder rate constants, k (yr ), for all important
chemical, photochemical or biological degradation path
ways, by subcompartment;
i
. 5) The rate of input of the chemical, I (mol/yr), into each
subcompartment; and
VI4

6) Transfer coefficients, D (mol yr atm )', foreach
intercompartmental transfer process (e.g., volatilization)
to be modeled. For volitization from water, D will require
only H and MW as chemicalspecific input parameters.
The bioconcentration factor for aquatic life, BCF, would have been
7
required if the Biota subcompartment had been kept in the Level III
calculations. .1
[• • .
D. Level III Equations '
The basic tenets of the fugacity approach used for the Level T
and II calculations (see Sections ill and V) are also valid for the
Level III calculations. The parameter symbols used below are the same
as in the Level I and II calculations.
The Level III calculations go beyond the Level II calculations by
allowing'a steadystate flux of the chemical, I (mol/yr), into any
subcompartment i. Intercompartmental transfers are modeled as a
flux, D (f  f.)» as shown in equation AO. Degradation within
a compartment is given (see eq. 38 in Section V) by the product V C K .
At equilibrium'the inputs and outputs in each subcompartment must be
equal:
li'Wi+yDyX' V (46)
The summation is over all compartments except i and must include
terms for each transfer process being considered. Remembering that
C = Zf, equation 46 can be reqritten as: '
• hfi 'Wi+ § V> .f Vi . (47)
In practice, equation 47 must be written out for each subcompartment
being considered, and then the set of siraulatarieous equations solved
for the f. values. Considering four subcompartmehts (e.g., air,
water, sediments and soil) will thus yield four simultaneous equations
to be solved for f1, f«, f_ and f,. Calcualtions can then be made for
M, C, R and T in a manner similar to that used in the Level II equations.
• VI5

StepbyStep Instructions
(D\
(2)
(3)
(4)
Steps (1) through (4) are the same as were
given previously for the Level II calculations
(see Section VD)
(5) Calculate V.Z.K (mol yr atm ) for each subcompartment.
(6) Calculate or select an exchange coefficient, D (mol yr^atm"1),
for each intercompartmental transfer process of interest, e.g.,
volatilization from soil and/or water, adsorption, uptake by
biota, etc. For volatilization from water, D is given by equation
41; the Kp parameter needed in equation 41 may be evaluated from
equation 42, 43, 44 or 45, as appropriate. Values of D for other
transfer processes must be assumed; no equations were given by
MacKay (op. cit.) for their calculation.
(7) For each subcompartment 1, write out the mass balance equation
given by equation 47. If there are n subcompartments, there will
be n simultaneous equation which must then be solved for the
chemical's fugacity in each compartment, f.(atm).
(8) Calculate the mass of the pollutant in each subcompartment, M., from:
M^mol) = f±V1Zi (48)
and then calculate the total amount of the pollutant in the model
environment from EjM..
VI6

(9) Calculate the concentration of the pollutant in each .
subcompartment with:
C± (mol/m3) = Z±fi = Mi/V± . (49)
Conversion to units of ppt may be made as described previously
for the Level II calculations.
(10) The rate of removal of the pollutant from each subcompartment,
R± (raol/yr), is  by definition — equal to I in the Leva! Ill
calculations. • .
(11) Calculate the average residence time (T) of the pollutant in the
model environment from:
T (yr) = E±MI/EIII (50)
E. Level III Sample Calculation
A sample Level III calculation is presented for trichloroethylene
in a fourcompartment model environment identical to the one described
for the Level II test set. The values of the input parameters used here,
although considered reasonable, should not be considered to be the
"best" values (or even defensible in some cases); they were selected
primarily to allow the sample calculation to be run.
For trichloroethylene we have used MW = 131.4 g/mol,
H = 9.1 x 10 3 atm m3/mol, K = 38 and the same degradation rates
assumed for the Level II calculations (see Section V, Table 17). The
selected values of I. and (previously) calculated values of V.Z.K. are
as shown below.
VI7

Compartment.
Number
1
2
3
4
Compartment
Air
Surface water
Sediment
Soil
Input
di)
mol/yr
. . 48
11
0
38
v^tc,
2.62 x 1013
7.59 x 107
1.34 x 107
7.48 x 107
Total 97
The total input (97 mol/yr) is the same as was used in the Level II
sample calculations.
This sample calculation considers the following intercompartmental.
transfer processes:
Process Transfer Coefficient
Volatilization from water D12 (
Volatilization from soil DH+ (
Adsorption on sediments T>23 (. 032)
Assuming an air speed of 5 m/s, a current speed of 0.5 m/s, and a mean
•water depth of 3 m, allows calculation of K from equation 44:
G
K_  87.6 [(0.057 x 9.1 x 10~3 I 3.77 x 10~5) V131.4]'1
t
 1.37 x 101* m/yr •
When this is substituted in equation 41 (with the interfacial area
a = 5 x 101* m2), Di2 is calculated as:
D12 = 137 x 10^(5 x 10^/2.4 x 152
= 2.85 x 1010 mol yr~ l atm~ l
VI8

For the initial calculation we will assume Dm = 1010 mol/(yr atra) and
D23 ° 1012.mol/(yr atm) . Since the uai*/sediment , soil/sediment and
soil/water compartment pairs have no common interface, we set
D13 = D31 = °» D3it " Di»3 * 0 and D2^ • Di+2 = 0.
The, general form of the four simultaneous equations (based on
equation 47) that require solution is:
12 + Dm)f!  (D12f2 + Duf^) (51)
I2 = (V2Z2K2 + D12 + D23)f2  0>i2fl + D23f3> ' '(52)
I3 = (V3Z3K3 + D23)f3  (D23f2) •>•.• (53)
(54)
Substituting in the input values given above gives:
For:
i  1 48 = (2.62 x 1013 + 2.85 x 1019 + 1019)fi  (2.85 x 1010f2 + 10
i = 2 . 11 = (7.59 x 107 + 2.85 x 1010 + 1012)f2  (2.85 x lO^f! + 101
i = 3 oQ (1.34 x 107 +.1012)f3  (1012f2) •,'
i = 4 38  (7.48 x 107 + 1010)f4  (1010fi) :
Collecting terms yields: .•••.
48  2.62 x 1013f!  2.85 x 1010f2  1010fH
11   2.85 x lO10^ + 1.03 x 1012f2  1012f3
0  . _ 1012f2 + 1012f3
38   1010f 1 + 1.01 x
VI9

The solution of this set of simultaneous equations yields:
fl = 3.67 x 1012 atm
f2  fs  3. 70 x HT10 atm
fn  3.77 x 109 atm
Steps 8 and 9 of the stepbystep instructions (equations 48 and
49) are then used to find the mass (M.) and concentration (C.) in each
compartment. The results are shown below and the predicted
concentrations compared with the Level II output.
M± (mol) =
C. (mol/m) =
C'± (ppt) =
CC from
Level II (ppt) =3.7 0.054 0.20 0.041
For this example we also have a total pollutant load in the model
environment (£M ) of 1.63 mol and an average residence time (T) of
0.017 yr (6.1 d). The Level II calculations predicted 1.54 mol and 5.8 d,
respectively. The significant differences in the predicted values of C.
for the Level II and III calculations (for the water, sediment and soil
compartments) should be noted.
1
Air
1.53
1.5 x 10'10
3.7
2
Water
6.1 x 103
4.,1 x 10 8
5.3
3
Sediment
1.5 x HP 3
3.1 x ICT7
20
4
Soil
8.8 x 10~2
t .
6.3 x lO7
41
VI10

Sensitivity Analysis ' '
The Level III calculations introduce two new parameters: sub
compartmentspecific inputs (I.) and intercompartmen'tal transfer
coefficients (DJ^)« The sensitivity of the model outputs to variations
in these inputs will depend, in part, on the values of many of the other
chemical and environmentspecific inputs. Thus, generalizations are
not possible and the user must conduct his/her own sensitivity analyses
on a casebycase basis.
Table 19 presents the results of a (partial) sensitivity analysis
for the trichloroethylene calculations described above. This table
shows the results of the Level I and II calculations followed by eight
Level III cases in which the D., and I, values were changed. Case No. 1
(Base Case) is the one described in detail in the text above. In
Case Nos. 24, values of Dm and 023 (which had been guessed at for the
base case) were varied over three to four orders of magnitude, generally
resulting in minor changes in the predicted concentrations. In.Case
Nos. 58, the subcompartment inputs (Ii  1^) were varied, but the total
input was kept at 97 mol/yr. In Case No. 5, no discharge to water is
allowed and the air and soil compartments receive about 60% and 40%,
respectively. In Case Nos, 68, all of the discharge is to one compart
ment: the air, soil, and. water compartments, respectively. In these
latter cases (Nos. 58 vs. Base Case) the model output, excepting the
air .compartment, is seen to be fairly sensitive to the varying I. inputs.
One general conclusion that might be made from the analysis above
is that predicted concentrations for a subcompartment that contains a
large"percentage of 'the total mass of the chemical (e.g., air for tri
chloroethylene) will be fairly insensitive to changes in Dj. and IA
variations. The converse statement would be equally valid.
viii

TABLE 19
Sensitivity of Level III Outputs to D.. and I Values.
Test Calculations for Trichloroethylene
Method of
Case No. Calculation Air
' . Level Ib '240
" Level IIC 3; 7
A
Concentration (ppt)
Water
3.5 '
0.054'
Sediment
13
0.20
in:
Soil
2.6
0.041
Level III:d ' :
1 Based 3
2 D23=109 3
3 Dm
4 DI^
IX =
5 I2=
I«»"
6 fll =
(I2=
=108 3
=1012 3
59
1 3=0 3
38
•'• } ,
13=1^=0 J
? ( IjIjlgO ) 3
Il =
8 I2=
I3=
;
D i
i
97 [ 3
Ij,=0 )
.7
.7
.1
.7
.7
.7
.7
.5
5.3
5.5
5.3
5.7
0.050
0.050
0.050
46
20
21
20
22
0.19
0.19 
0.19
170
41
41
24
0.45
41
0.040
100
0.038
a. ppt (v/v) for air and ppt (w/w) for other compartments.
b. Level I calculation assumed 100 moles of chemical were in the model
environment. No degradation allowed.
c. Level II calculation assumed total input of 97 mol/yr into model
environment. Degradation allowed. Mass of chemical in compartment
calculated to be 1.54 mol.
d. All Level III calculations assumed total input to model environment
was 97 mol/yr. Base case is the example worked out (in detail) in
the text where:
VI12

TABLE 19 (cont.)
D12 = 2.85 x 1010 Ii  48
D^ = 1010 I2  11 :
D23 = lQia I3 = 0
Ik = 38
In runs 2 through 8, changes in these input parameters were made as
indicated in the second column. For example, in Case No. 4 Dj^ was set
at lO1^; all other inputs remained as specified above for the base case.
VI13

VII. LIST OF SYMBOLS USED
. .
 ' 2
a = Area of common interface between two'subcompartments (m )
B = Volume fraction of biota in surface waters. (Assumed to be
5 x 10 m /m insample Level I calculations.)
BCF = Bioconcentratibn factor for aquatic life
C = .Concentration of chemical (mol/m )
C" » Concentration of chemical (ppt by volume in air and ppt by
weight in other compartments) . . "'
c = Concentration of soil or sediments in soil or sediments
s 3
compartments, respectively (g/m )
D = Transfer coefficient for transfer between subcompartments
(mol/yr. atm)
f = Fugacity of chemical (atm)
o mm Iff*
H ~ Henry's Law constant (atm m /mol) ( "Tjr: in Neely's equations)
I = Rate of input of chemical into model environment or a specific
subcompartment (mol/yr) •
i,j = Used as subscripts to identify subcompartments. See
Subscripts below.
K = Overall (or total) firstorder degradation rate constant for
chemical (yr )
k = Firstorder degradation rate constant for chemical (yr )
K,, = Overall gas mass transfer coefficient for volatilization (m/yr)
u
K = Soil or sediment adsorption coefficient base on organic
carbon content
K = Octanol water partition coefficient
K = Soil adsorption coefficient
M = Mass of chemical (mol)
MW = Molecular weight (g/mol)
N = Steadystate transfer rate for chemical between two subcorapart
ments (mol/yr)
(oc) ** Organic carbon content of soil or sediment (%)
P *» Vapor pressure of chemical (mm Hg)
VII1

5 3
R  Gas constant (8.2 x 10 atm ID /mol deg)
R = Total rate of removal of chemical from subcompartment i (mol/yr)
S « Solubility of chemical (mg/L) (mM/L in Neely's equations)
T = Temperature (K)
•1/2
Halflife for clearance from fish (hr)
t = Mean residence time of chemical.in model environment (yr)
3
V » Accessible volume of a subcompartment (m )
y « Fraction of aquatic biota that can be considered equivalent
to octanol
Z  Fuacity coefficient (tool m /atm)
Subscripts (i)
1
2
3
4
5
6
Level I Calculations
Air
Surface water
Suspended sediments
Bottom sediments
Aquatic biota
Soils
Level II and III Calculations
Air
Surface water
Bottom sediments
Soils
VII2

•• .VIII. REFERENCES
Blau, G.E. and W.B. Neely, "Mathematical Model Building with an Applica
tion to Determine the Distribution of Dursban Insecticide Added to a
Simulated Ecosystem," Adv. Ecol. Res.', £:133 (1975).
Callahan, M.A. jjt al., WaterRelated Environmental Fate of 129 Priority
Pollutants, U.S. Environmental Protection Agency, Report No. EPA440/
4~79029a and b (1979),
Gledhill, W.F., R.G. Kaley, W.J. Adams, 0. Hicks, P.R. Michael, V.W.
Saeger and G.A. LeBlanc, "An Environmental Safety Assessment of Butyl
Benzyl Phthalate," Environ. Sci. Technol., 14:30105 (1980).
Kenaga, E.E. and C.A.I. Goring, "Relationship Between Water Solubility,
Soil Sorption, OctanolWater Partitioning, and Bioconcentration of
Chemicals in Biota," prepublication copy of paper dated Oct. 13, 1978,
given at the Third Aquatic Toxicology Symposium, American Society for
Testing and Materials, New Orleans, LA, October 1718, 1978 [Symposium
papers published by ASTM, Philadelphia, PA, as Special Technical
Publication (STP) 707 in 1980.]
Mackay, D., "Finding Fugacity Feasible," Environ. Sci. Technol., 13;
121823 (1979).
Neely, W.B. (Dow Chemical Co., Midland, MI), "An Integrated Approach
to Assessing the Potential Impact of Organic Chemicals in the Environ
ment," preprint of paper presented at the workshop on "Philosophy and
Implementation of Hazard Assessment Procedures for Chemical Sub
stances in the Aquatic Environment," held August 1418, 1978 in
Waterville Valley, NH (1978a).
Neely, W.B., "A Method for Selecting the Most Appropriate Environmental
Experiments that Need to be Performed on a New Chemical," in Preprints
of Papers Presented at the 176th National Meeting, Miami Beach, FL,
September 1015, 1978; American Chemical Society, Division of Environ
mental Chemistry, Vol. 18, No. 2, p. 3367 (1978b).
Neely, W.B. and G.E. Blau, "The Use of Laboratory Data to Predict the
Distribution of Chlorpyrlfos in a Fish Pond," in Pesticides in the
Aquatic Environment, Plenum Publishing Co., New York (1977).
Neely, W.B., "A Preliminary Assessment of the Environmental Exposure
to be Expected from the Addition of a Chemical to a Simulated Aquatic
Ecosystem," Int. J. Envron. Sci. (1978c).
Tabak, H.H., Blodegradability Studies with Priority Pollutant Organic
Compounds, Staff Report (Draft), U.S. Environmental Protection Agency,
Environmental Research Center, Cincinnati, Ohio (1980).
VIII1

Thomas, R.G., "Volatilization from Water," draft report in Monthly
Report No. 18 submitted by Arthur D. Little, Inc., to the U.S. Army
Medical Research and Development Laboratory, Fort Detrick, Frederick,
MD, under Contract No. DAMD1778C8073 (April 7, 1980).
Veith, G.D., K.J. Macek, S.R. Petrocelli and J. Carroll, "An Evaluation
of Using Partition Coefficients and Water Solubility to Estimate Bloeon
centration Factors for Organic Chemicals in Fish," J. Fish. Res. Board.
Can. (1980).
VII12
 