*>EPA
United States
Environmental
Protection Agency
EPA 600/B-23/345 | Febuary 2024 | www.epa.gov/research
Users Guide for the All Ages Lead Model
(AALM) version 3.0 - Excel User Interface
and Fortran Model Executable
Office of Research and Development
Center for Public Health and Environmental Assessment
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x=,EPA
EPA/600/B-23/345
United States February 2024
Environmental Protection
Agency
Users Guide for the All Ages Lead
Model (AALM) version 3.0 - Excel
User Interface and Fortran Model
Executable
Center for Public Health and Environmental Assessment
Office of Research and Development
U.S. Environmental Protection Agency
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AALM v3.0 Users Guide
DISCLAIMER
This document has been reviewed in accordance with U.S. Environmental Protection Agency policy and
approved for publication. Any mention of trade names, manufacturers or products does not imply an
endorsement by the United States Government or the U.S. Environmental Protection Agency. EPA and
its employees do not endorse any commercial products, services, or enterprises. This document was
developed, and the work described in it was conducted, under contracts EP-W-17-008, EP-W-09-031, EP-
BPA-ll-C-018, EP-13-H-000037, EP-08-H-000055, EP-C-14-001, and 68HERC22D0004.
DISCLAIMER OF SOFTWARE INSTALLATION /
APPLICATION
Execution of any installation program, and modification to system configuration files must be made at
the user's own risk. Neither the U.S. EPA nor the program author(s) can assume responsibility for
program modification, content, output, interpretation or usage. AALM 3.0 has been extensively tested
and verified. However, as for all complex software, these programs may not be completely free of errors
and may not be applicable for all cases. In no event will the U.S. EPA be liable for direct, indirect, special,
incidental, or consequential damages arising out of the use of the programs and/or associated
documentation.
QUALITY ASSURANCE
This report was prepared by EPA with assistance from SRC, Inc. and ICF. EPA has an agency-wide quality
assurance (QA) program that is outlined in the EPA Environmental Information Quality Procedure, CIO
2105-P-01.3, and follows specification outlined in EPA Environmental Information Policy CIO 2105.3.
Quality assurance for this research is documented in a Quality Assurance Project Plan (QAPP), entitled
All Ages Lead Model (AALM) Development, EPA QAPP ID: L-HEEAD-0033877-QP-1-0, August 10, 2023.
AUTHORS AND CONTRIBUTERS
Dr. James S. Brown — Center for Public Health and Environmental Assessment, Office of Research
and Development, U.S. EPA, Research Triangle Park, NC
Dr. Gary L. Diamond — SRC, Inc., North Syracuse, NY
Dr. Mark H. Follansbee — SRC, Inc., Scarborough, ME
Dr. Graham Glen — ICF, Durham, NC
Dr. Cara Henning — ICF, Durham, NC
Ms. Rachel O'Neal — ICF, Durham, NC
Ms. Delaney Reilly — ICF, Durham, NC
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AALM v3.0 Users Guide
Table of Contents
DISCLAIMER 1
DISCLAIMER OF SOFTWARE INSTALLATION I APPLICATION 1
QUALITY ASSURANCE 1
AUTHORS AND CONTRIBUTERS 1
Table of Contents 2
List of Tables 3
List of Figures 4
I. A Brief History of the Leggett Model and an Introduction to the All Ages Lead Model 5
1. The All Ages Lead Model and an Exposure Interface 5
2. Adapting the Exposure Interface for AALM 6
3. User Interface and FORTRAN Updates 7
II. Overview of the Excel User Interface and FORTRAN Model 7
III. How to Setup and Run the AALM version 3.0 Using the Excel Interface 10
1. This section of the User's Guide provides a brief description of how to configure the user
interface (GUI) and run the FORTRAN model. Unzip the Model File Package 10
2. Complete the Simulation Control Tab and Modify Model Parameters as Needed 10
Simulation Name: The name of the output text files 11
Advanced Time Options 12
Base Parameters 13
Growth Parameters 13
Physiological Parameters 14
Time-dependent Parameters 14
Time-independent Parameters 16
Media Parameters 20
Filling in Media 22
Switch to indicate solution type 25
Switch to indicate stepwise or interpolated transitions between exposures 27
Switch to indicate if red blood cell (RBC) should be linear or allow for saturation 27
3. Run the Model and Review the Results 28
Detailed Outputs 30
Daily 32
4. QA Step: Confirm the Intake Results Give the Correct Time Series 33
IV. T roubleshooting 33
V. Appendix 35
Default Values 36
Mask Examples 50
Example 1: Children's camping over several years 50
Example 2: Youth summer day camp exposures from 6 to 19 years inclusive 51
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AALM v3.0 Users Guide
Example 3: Dietary Supplements taken on regular schedule 52
Example 4: Therapeutic home remedies 53
AALM Example Scenarios 54
Example 1: IEUBK Exposure Scenario 54
Example 1a: lEUBK Exposure Scenario 55
Example 2: Background BLL 56
Example 2a: Background BLL 56
Example 3: Background BLL and Short-term Soil Exposure 57
Example 3b: Background BLL and Short-term Soil Exposure 57
Example 4: Occupational Air Exposure 57
Example 5: Occupational Air Exposure 58
List of Tables
Table 1 - Timesteps between outputs (outwrite): How Often the Outputs should be Written to
the Output File 12
Table 2 - Base parameters 15
Table 3 - Growth Curve Parameters 14
Table 4 - Time Dependent Model Parameters 15
Table 5 - Time Independent Model Parameters 17
Table 6 - Parameters used in Media Tab 22
Table 7 - Lung Parameters 24
Table 8 - Model Options for Forward and Solve for Allowable Concentration Simulations 25
Table 9 - Stepwise or Interpolated Transitions for Exposure Intakes 27
Table 10 - Choice of Linear or Nonlinear binding to RBC 28
Table 11 - Output Parameters Displayed on the Detailed Outputs Tab 31
Table 12 - Output Parameters Displayed on the Daily Tab 32
Table 13 - Troubleshooting Questions and Answers 33
Table 14 - Default Model Values 37
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AALM v3.0 Users Guide
List of Figures
Figure 1 - Screenshot of Simulation Setup Screen 9
Figure 2 - Screenshot of Water setup in Media tab 21
Figure 3 - Lung Parameters screenshot 25
Figure 4 - Screenshot of Setup for Allowable Concentration Solution 27
Figure 5 - Button to Run a Simulation 28
Figure 6 - Output Section Screenshot 29
Figure 7 - Graphs that Users may Select to Display 30
Figure 8 - Screenshot 1 for Applying Masks to Camping Scenario 50
Figure 9 - Screenshot 2 for Applying Masks to Camping Scenario 51
Figure 10 - Screenshot 3 for Applying Masks to Camping Scenario 51
Figure 11- Screenshot for Applying Masks to Summer Camp Scenario 52
Figure 12 - Screenshot 1 for Applying Masks to an Adulterated Dietary Supplement 52
Figure 13 - Screenshot 2 for Applying Masks to an Adulterated Dietary Supplement 53
Figure 14 - Screenshot 3 for Alternative to Masks to an Adulterated Dietary Supplement 53
Figure 15 - Screenshot for Adulterated Therapeutic Home Remedies Scenario 54
Figure 16 - Screenshot with Masks for Adulterated Therapeutic Home Remedies Scenario....54
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AALM v3.0 Users Guide
I. A Brief History of the Leggett Model and an
Introduction to the All Ages Lead Model
The Leggett biokinetic model (Leggett RW. 1993. Environ Health Perspect. 101(7):598-616)
simulates the intake, exchange, and excretion of lead in humans from birth through adulthood
using a series of body compartments with mass exchange between them. When the model was
originally coded, it synthesized a wide variety of sometimes disparate sources of information
related to the biokinetics of lead in humans. The Leggett model was informed by:
¦ Lead tracer studies of injection, ingestion, and inhalation in healthy adult humans,
¦ Measurements of lead in environmentally exposed men, women, and children at autopsy,
¦ Lead mass-balance studies on adult humans,
¦ Bioassay and autopsy measurements on occupational^ exposed subjects,
¦ Lead studies in laboratory animals at different life stages
¦ Experimental, occupational, environmental, and medical data on the biokinetics of elements
that serve as physiological analogues of lead, and
¦ Basic physiological information on the human body.
As such, the Leggett model structure is a minimal system of body compartments and mass
exchange terms needed to synthesize all these data sets. The modular form of the model allows
investigators to modify specific parameter values to address special problems in lead toxicology
or to incorporate new information related to lead biokinetics. The original Leggett model
included:
¦ Input file: an ASCII input file containing information describing the lead exposure
scenario and the age-dependent lead transfer rates for each compartment, and
¦ Model code: an executable FORTRAN program which reads the input file, performs the
prescribed calculations, and writes the outputs to an ASCII file.
This approach was designed to provide maximum flexibility and versatility rather than to be
user-friendly.
1. The All Ages Lead Model and an Exposure Interface
The original Leggett model has, on several occasions, been translated onto other software
platforms or into other programming languages. One notable example is the inclusion of the
Leggett model in the Environmental Protection Agency's (EPA) All Ages Lead Model (AALM). In
collaboration with EPA, SRC, Inc. recoded the model in the acsIX programming language.
Unlike FORTRAN, this programming language comes with off-the-shelf differential equation
solvers supporting variable time steps, along with other functions (such as "TABLE") that easily
allow input parameters to vary in time during the simulation.
SRC also added an Excel user interface that expanded the Leggett model to incorporate
exposure estimation. The original Leggett model accepts inputs of inhalation and total oral
intake in units of jag lead/day. The Excel user interface allows the user to enter time-varying air
concentrations (|a,g lead/m3 air); soil and dust concentrations (|a,g lead/g dust); water
concentrations (jag lead/L water); inhalation rates (m3 air/day); soil and dust ingestion rates (g
dust/day); water ingestion rates (L water/day); and food and "other" intake rates (|a,g
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AALM v3.0 Users Guide
lead/day).The user can also specify relative absorption factors for air, soil, dust, water, food, and
"other" sources. The Excel interface writes input files for the acsIX code and the acsIX code
incorporates the different media concentrations, media intake rates, and relative absorption
factors to estimate total inhalation and total ingestion uptakes at each model time step. This
feature greatly improved the versality of the model, and made it more user-friendly, since users
could record and run a wide variety of exposure scenarios in a transparent way.
As part of coding and testing the AALM, EPA and SRC simulated a number of datasets,
including adult and childhood datasets used during the original Leggett code calibration and
validation as well as additional datasets identified during a literature search. Based on these
tests, parameters were adjusted to ensure the best overall fit against all datasets. A full report
documenting the datasets and parameter changes was provided to EPA and serves as a
technical support document for this user guide.
2. Adapting the Exposure Interface for AALM
As noted above, acsIX provides a number of benefits compared with a FORTRAN executable,
and the AALM Excel interface improved versatility and made the model more user-friendly for
estimating exposure profiles. However, acsIX is proprietary software, limiting the availability to
some stakeholders. Then, in 2015, makers of the acsIX simulation language announced the
language would be "sunsetted", meaning no new licenses would be sold. The EPA Office of
Pollution Prevention and Toxics was already using the FORTRAN version as part of the Lead
Renovation, Repair, and Painting analyses for public and commercial buildings; because of the
number of simulations needed for this Monte Carlo analysis, acsIX was not practical and EPA
required the speed and efficiency inherent in the FORTRAN language to complete the analysis.
As part of that project, EPA OPPT worked with EPA ORD to evaluate the differences between
the AALM and the Leggett FORTRAN code and to harmonize the inputs. They re-evaluated the
parameters against all datasets and also demonstrated that the acsIX and FORTRAN versions,
when configured with the same growth algorithms and input parameters, returned results to
within +/- 5% of each other for a range of exposure scenarios in both children and adults. The
final product included an acsIX version of the All Ages Lead Model (AALM.CSL) and a
harmonized FORTAN version (AALM.FOR), which was referred to as the All Ages Lead Model
(AALM) version 2.0.
To help allow other researchers and regulators to use the FORTRAN version, particularly in the
face of the acsIX "sunsetting", EPA and ICF have created an Excel user interface. The goals of
this user interface are:
1) To maintain the format and functionality of the AALM.CSL Excel interface, particularly
with respect to exposure estimation,
2) To adapt the tool to create the input files for the AALM.FOR and to call the FORTRAN
executable directly to allow the user to run the Leggett AALM algorithms without acsIX,
and
3) To provide a user's guide to help users to understand how to setup and run the
simulations in this version.
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AALM v3.0 Users Guide
3. User Interface and FORTRAN Updates
The AALM version 2.0 and associated technical documents were reviewed by an EPA Science
Advisory Board (SAB). The SAB review of the AALM version 2.0 and associated documentation
consisted of a two-day public meeting in October 17-18, 2019 and teleconferences on April 23
and June 23, 2020. The final August 2020 review report is posted on the SAB website:
https://sab.epa.gov/ords/sab/f?p=100:0:8979490196190:APPLICATION_PROCESS=REPORT_
DOC:::REPORT_ID: 1086). The SAB provided Tier 1 (recommended revisions), Tier 2
(suggestions), and Tier 3 (future considerations). The AALM version 3.0 incorporates revisions
in responses to all SAB Tier 1 and most Tier 2 comments, as well as some Tier 3 comments.
Beginning in April 2021 in response to SAB feedback, the user interface was updated to be
more intuitive to use. Many of these updates included reorganization of tabs and information,
increased use of macros and automation to guide the user through the tool, and introduction of
processes to reduce how much the user needs to do to interact with the data. Further, the
interface was updated to decrease visual clutter without content loss and to guide the user
through providing acceptable, accurate data for the model, housed in FORTRAN.
The FORTRAN code was updated in several ways. First, a revised lung model was
incorporated. Second, the contributions from the different inhalation and ingestion sources can
now be tracked. This includes differing absorption and/or lung clearance rates by source. Third,
explicit mass balance calculations have been added, both for total Pb and by source. Fourth,
the code's processing time has been decreased through the introduction of several process
efficiencies, including extensive vector and array processing. This also allows for more
timesteps to be simulated. Details of these changes can be found in the AALM Technical
manual. The AALM version 3.0 has been tested exclusively on computers with a Microsoft
Windows operating systems. The AALM Fortran code and Excel Interface have not been used
or tested on other systems (i.e., Apple, Linux) at this time.
II. Overview of the Excel User Interface and
FORTRAN Model
The Excel user interface to AALM.FOR model consists of the following pieces:
• The Excel GUI: For quick start examples that
o Simulation control (Figure 1, Tables 1 and 2) can be loaded into the Excel
o Growth Parameters (Growth Params; Table 3) GUI, see the Appendix,
o Time-dependent Physiological Parameters
(Time Dep Phys Params; Table 4)
o Time-independent Physiological Parameters (Time Ind Phys Params; Table 5)
o Media (Figure 2, Table 6)
o Lung (Figure 3, Table 7)
o Fortran input file
o Solution type (Figures 4 and 6, Table 8)
o Transitions between Exposure Times (Table 9)
o Binding to RBC (Table 10)
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AALM v3.0 Users Guide
o Explore Data (Figures 6 and 7)
o Summary
o Output (Table 11)
o Daily (Table 12)
• The Leggett executables:
o These are 32- or 64-bit executables that are called by the Excel file to run the
model. It is recommended that the default 64-bit executable is used.
• Leggettlnput.txt:
o This file is written with each simulation's FORTRAN inputs. It is a static reference
for the file to retrieve these inputs.
• Supplementary files:
o The user's guide (this document)
o AALM Fortran code (AALM_20240209.f90): The Leggett model text file that was
compiled to create the Leggett executable. It is not needed to run the model but
may be needed by some researchers who wish to make future changes to the
model algorithms,
o Technical Support Document
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AALM v3.0 Users Guide
Import
All Ages Lead Model (AALM)
O
Reset
Simulation Setup
Simulation Name SimName
1. Set Base Parameters
Age at start (yrs)
Age at end (yrs)
Sex
Q 32-b'itexe
64-bit exe
©
©
©
Select to see advanced time options:
2. Set Growth and Physiology
Adjust growth parameters?
Adjust physiology parameters?
No (default)
No (default)
©
©
3. Set Active Media
Soil
Dust
Water
Air
Food
Other
Solution type
Stepwise or Interpolated?
Linear or Non-linear RBC?
Media
Number of
Sources
Number of
Periodic
"Time Masks"
No
0
0
No
0
0
No
0
0
No
0
0
No
0
0
No
0
0
©
©
©
©
©
©
Stepwise
©
©
©
Run Simulation
Figure 1 - Screenshot of Simulation Setup Screen
To run the model users must configure the Simulation Control tab variables. Based on which
fields are indicated for adjustment, other tabs will appear for the user to navigate to in order to
update the parameters under each heading. Follow the prompts until all fields are updated as
desired. When ready, select "Run Simulation" at the bottom of the Simulation Control tab. This
action will then:
1. Create the FORTRAN input file, which can be reviewed by the user,
2. Run the FORTRAN executable (32 or 64 bit as selected by the user), and
3. Import the results of the simulation back into Excel for interpretation and visualization.
Please note: to create the 32 and 64-bit executables, ICF used the proprietary Intel FORTRAN
compiler. As such, the compiler itself is not provided as part of the package. This compiler
version was needed to get the model to properly compile. ICF also attempted to compile the
model using free FORTRAN compilers, including the GNU compiler. However, the code
returned errors in the compilation during our testing.
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AALM v3.0 Users Guide
III. How to Setup and Run the AALM version 3.0 Using
the Excel Interface
1. This section of the User's Guide provides a brief description
of how to configure the user interface (GUI) and run the
FORTRAN model. Unzip the Model File Package
To begin to use the model, unzip the zip file and place the contents in any folder on your C:\
drive. You can save different Excel files for each of your different simulations, and these can be
in different folders on your computer.
Each time you run AALM, the following files must be in the same folder:
1. AALM_32.exe and AALM_64.exe (the model executables)
2. AALM.xIsm
Next you can open the Excel GUI.
For some versions of Excel, the first time (or every time, depending on security settings) you
use the tool, you may need to enable the macros within the file when you open it as well. When
you open the tool, a yellow bar will appear at the top with a button "Enable Content?". Click the
button to enable the macros. If this button does not appear, you can also do the following:
1. Click the Microsoft Office Button, and then click Excel Options.
2. Click Trust Center, click Trust Center Settings, and then click Macro Settings.
3. Click the options to enable the macros.
While not required, it is generally advisable to close other Excel files when running the AALM.
Further, users should not have more than one instance of AALM open at a time. Users may
compare the outputs of multiple simulations within the same instance of the tool, which should
eliminate the need to have multiple workbooks open. As discussed in Section 3 of this
document, an Excel csv file (Out_[simulation name],csv) contains the output of a simulation
within a folder (simulation name) created by the AALM.
2. Complete the Simulation Control Tab and Modify Model
Parameters as Needed
To run a simulation, begin with the Simulation
Control tab. This tab will walk through each of the
other tabs that should be changed based on
which parameters are indicated as needing
adjustment. All other parameters will remain hidden
Parameters which the user may change are in yellow throughout the GUI. These fields are also
indicated in text.
Reset buttons fill parameter values with
Additionally, throughout the GUI, selecting "Reset" default values while Clear buttons erase the
will set all parameters back to default values while parameter data.
Yellow cells indicate values that can be
adjusted by the user if desired. Other cells
should not be edited.
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AALM v3.0 Users Guide
selecting "Clear" will erase all the parameter data. Reseting is particularly useful for growth
curves (Table 3), Time dependent parameters (Table 4), Time independent parameters (Table
5), and Solve for Allowable Concentration (Figure 6, Table 8).
Further, the "Import" buttons on the Simulation Control and Explore Data tabs can be used to
import inputs and results of previously run scenarios, respectively.
Simulation Control primarily contains the Leggett TU . .. ,, 0. , ,. ^ , ,
r 3 . The import buttons on the Simulation Control
input parameters that control the following. anC| EXp|0re Qata a||OW users to load
1. Simulation Name: The name optionally previously run inputs back into the GUI or
. ...¦ ¦ . . .. analyze previously run data,
given by user that is associated with the
current simulation. This will correspond to the input and output files generated.
2. Advanced Time Options:
a. How often AALM calculates lead kinetics each day (timesteps per day).
b. How often the calculations should be written to the output file (that is, how many
time steps there are between each output).
3. Base Parameters:
a. The age of the modeled individual at the beginning of the simulation, i.e., 0 years.
Users do not have access to change this parameter.
b. The age of the modeled individual at the end of the simulation.
c. The sex of the modeled individual (for estimation of growth parameters).
4. Growth Parameters
5. Physiological Parameters
6. Media Parameters
7. Lung Parameters
8. Solution type, either forward or to solve for an allowable level.
9. Stepwise or interpolated transitions between exposures.
10. RBC binding (linear or non-linear allowing for saturation).
Simulation Name: The name of the output text files
The user can type in the name of the folder and files generated when a simulation is run. This
name will be used for all simulation specific files tabs created. If the user does not create a
unique name, Excel will overwrite the previous folder and files. It will warn the user before this
happens so the user can revise the simulation name before the program overwrites previous
outputs.
This field does not allow for special characters except for an underscoreUsers can use all
letters and numbers in addition to this character. Spaces are not allowed as they are not
interpreted correctly by FORTRAN. Additionally, this field does not allow for names longer than
20 characters. In the event that a simulation name that does not fit these parameters (special
characters used or the length requirement is not met) is provided to the interface, users are
reminded of these requirements with a descriptive error message.
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AALM v3.0 Users Guide
Advanced Time Options
Unless the user selects "Select to see advanced time options" and alters the two parameters in
that section, they will be set to the default values as noted in the table below and in the
appendix Default Values.
If deviating from the default parameters, the user must decide what time steps to use and how
often to export the model results. This will impact output specificity, which could impact analysis
of the results. The interplay between these variables is explained in this section. The calculation
is straightforward and uses a single time step for the full simulation.
Timesteps per day (steps_per_day)
Determine the number of timesteps to be used
per day. In general, time steps should be
shorter than the fastest biological process or
the fastest rate of change in exposure. If
exposure is varying quickly (e.g., due to an
acute exposure scenario), the time step needs to be short and overall runtime becomes longer.
The default for this parameter of 100 timesteps per day, which is one timestep every 14.4
minutes, is recommended.
For use with the 32-bit executable, timesteps per day cannot exceed 12 (based on processing
needs). For the 64-bit executable, timesteps per day have not been found to be limited in the
same way, though greater than -500 timesteps per day significantly slow down the processing
time of the model.
Table 1 - Timesteps between outputs (outwrite): How Often the Outputs should be Written to
the Output File
Parameter
Name in FORTRAN
Location
Default
Parameter
Prompt in User
Input File
Value
Limits
Interface
Timesteps per
Cannot exceed
day
steps_per_day
Simulation
Control
100
12 when using
the 32 bit
executable.
Timesteps
between
outputs
outwrite
Simulation
Control
100
Must be positive
The user may decide how often the model should write the output variables to the output file.
This variable (outwrite) uses the number of time steps as its unit. If the time step is 0.5 days and
the outwrite is 730, the outputs will only be written once every year (0.5*730). This helps to
control the file size of the output file so that not every time step is saved.
PLEASE NOTE
Timesteps per day must not exceed 12
when using the 32-bit executable or 20 when
using the 64-bit executable.
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AALM v3.0 Users Guide
The default for this parameter is 100, meaning one output will be written for every 100
timesteps, which if using the default value in timesteps per day (100) means one output is
written per day.
Base Parameters
Age at start and Age at end (age_range)
Because lead accumulates in the body, it is
generally necessary to model the entire
lifetime exposure of an individual starting at
birth. The Age at start parameter is 0 years
(birth) and not accessible to users. The default end of the simulation is age 90, but this can be
any value greater than the start age value, up to 100 years when using the 64-bit executable.
Sex: The sex of the modeled individual (for estimation of growth parameters)
Next the user specifies whether the modeled individual is a male or a female. The AALM uses
growth algorithms that vary for males and females. Thus, the choice of sex does not control any
biokinetics in the model, but it does affect the predicted concentrations by altering the volume of
the modeled tissues/compartments over which the lead mass is distributed.
Table 2 - Base parameters
PLEASE NOTE
Age at end cannot exceed 8 years when
using the 32-bit executable.
Parameter
Name in
Location
Default
Parameter Limits
Prompt in User
FORTRAN
Value
Interface
Input File
Age at start (yrs)
age_range
Simulation
Control
0
Set to zero, not adjustable by
users
Age at end (yrs)
age_range
Simulation
90
Should not exceed 90 and must
Control
be greater than "Age at start"
Sex
sex
Simulation
Control
Female
Binary; Female or Male
Growth Parameters
The Growth Parameter tab contains the different growth parameters used by the model such as
weight, logistic constants, and the ratio of lean body mass to body mass. These parameters are
used in the simulation to calculate the body weight at each age, which informs lead
compartmentalization. The weight is calculated and graphed for easy visualization as:
DW ,.T age * 'Wchild Wadult
BW — wbirth + -—— ; 1- ¦
half + age 1 + k * e~^ * waduit * a9e
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AALM v3.0 Users Guide
After configuring the growth parameters, select "Done" to return to the Simulation Control tab
and continue configuring the simulation.
Table 3 - Growth Curve Parameters
Parameter
Prompt in
User
Interface
Name in
FORTRAN
Input File
Location
Default Value
Parameter Limits
sex
Sex
Growth
Params
Female
Male
Binary; Female or Male
wbirth
Wbirth
Growth
Params
3.3
3.5
Must be positive
wchild
wchild
Growth
Params
22
23
Must be positive
half
half
Growth
Params
3
3
Must be positive
wadult
wadult
Growth
Params
34
50
Must be positive
kappa
po
Growth
Params
600
600
Must be positive
lambda
lambda
Growth
Params
0.017
0.0095
Must be greater than 0
LB
LB
Growth
Params
0.85
0.88
Must be between 0 and
1
Physiological Parameters
The physiological parameters are broken out into time-dependent and time-independent
parameters.
Time-dependent Parameters
It is highly recommended that no changes be
made to any time-dependent parameter other than
the gastrointestinal absorption fraction (F1).
Altering any rate constants (unit: d~1) or deposition
fractions to compartments (unit: f) will alter mass
balance. It is also recommended that number of ages for time-dependent parameters be left at
the value of 11. Altering the number of ages could affect model mass balance.
Specified ages in this tab should be:
1. The minimum age of the simulation
2. Each age at which a parameter will
change value
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AALM v3.0 Users Guide
Before altering or filling in the time-dependent parameters, update the number of ages that
should be displayed. This number should be each time the value of the parameters will change
throughout the simulation time. Keep in mind this is across parameters, so the number should
be high enough to represent all the parameter changes needed.
There are no limitations on the number of ages that must or must not appear other than
requiring at least 1 age, so the parameters are represented in the inputs of the FORTRAN
model. Additionally, the first age should be the minimum age being simulated.
For each age provided, the parameter value will be used until the next value is given. This age
range can vary based on user preferences.
Table 4 - Time Dependent Model Parameters
Parameter Prompt in
Name in
Location
Default
Parameter
User Interface
FORTRAN
Value
Limits
Input File
F1
f1
Time Dep
Phys Params
Varied
Must be
between 0 and 1
AMTBLD
amtbld
Time Dep
Phys Params
Varied
Must be positive
FLONG
flong
Time Dep
Phys Params
0.6
Must be
between 0 and 1
GSCAL
gscal
Time Dep
Phys Params
Varied
No longer used.
RBLAD
rblad
Time Dep
Phys Params
Varied
Must be positive
RBRAN
rbran
Time Dep
Phys Params
0.00095
Must be positive
RCORT
rcort
Time Dep
Phys Params
Varied
Must be positive
RCS2B
rcs2b
Time Dep
Phys Params
Varied
Must be positive
RCS2DF
rcs2df
Time Dep
Phys Params
Varied
Must be positive
RDIFF
rdiff
Time Dep
Phys Params
0.023105
Must be positive
RKDN2
rkdn2
Time Dep
Phys Params
Varied
Must be positive
RLVR2
rlvr2
Time Dep
Phys Params
Varied
Must be positive
15
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AALM v3.0 Users Guide
Parameter Prompt in
Name in
Location
Default
Parameter
User Interface
FORTRAN
Input File
Value
Limits
RRBC
rrbc
Time Dep
Phys Params
Varied
Must be positive
RTRAB
rtrab
Time Dep
Phys Params
Varied
Must be positive
RTS2B
rts2b
Time Dep
Phys Params
Varied
Must be positive
RTS2DF
rts2df
Time Dep
Phys Params
Varied
Must be positive
TBONE
tbone
Time Dep
Phys Params
Varied
Must be
between 0 and 1
TFRAC
tfrac
Time Dep
Phys Params
Varied
Must be
between 0 and 1
TOBRAN
tobran
Time Dep
Phys Params
Varied
Must be
between 0 and 1
TOSOFO
tosofO
Time Dep
Phys Params
Varied
Must be
between 0 and 1
TOSOF1
tosofl
Time Dep
Phys Params
Varied
Must be
between 0 and 1
TOSOF2
tosof2
Time Dep
Phys Params
0.001
Must be
between 0 and 1
Time-independent Parameters
Time independent parameters remain constant
throughout the simulation or serve as a starting point for
further calculation, so necessarily require less user setup
than the time-dependent parameters.
These parameters are summarized below and
summarized in more detail in the Appendix as well as in
the GUI.
PLEASE NOTE
It is highly recommended that no changes
be made to any time-independent parameter
other than the maternal blood lead
concentration (BLDMOT).
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AALM v3.0 Users Guide
Table 5 - Time Independent Model Parameters
Parameter Prompt in
Name in
Location
Default Value
Parameter
User Interface
FORTRAN Input
File
Limits
ASHWT
ashwt
Time Ind Phys
Params
2800
Not currently
used in the
Leggett code.
BLDMOT
bldmot
Time Ind Phys
Params
0.62
Must be
positive
BONIN
bonin
Time Ind Phys
Params
0.32
Must be
between 0
and 1
BRANIN
branin
Time Ind Phys
Params
0.045
Must be
between 0
and 1
BRATIO
bratio
Time Ind Phys
Params
0.85
Must be
between 0
and 1
CRTWT
crtwt
Time Ind Phys
Params
4000
Must be
positive
H1TOBL
hltobl
Time Ind Phys
Params
0.45
Must be
between 0
and 1
H1TOH2
h1toh2
Time Ind Phys
Params
0.1
Must be
between 0
and 1
H1TOSI
hltosi
Time Ind Phys
Params
0.45
Must be
between 0
and 1
HCTA
hcta
Time Ind Phys
Params
0.41 (female)
0.46 (male)
Must be
between 0
and 1
HCTB
hctb
Time Ind Phys
Params
0.52
Must be
between 0
and 1
HEPIN
hepin
Time Ind Phys
Params
0.055
Must be
between 0
and 1
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AALM v3.0 Users Guide
Parameter Prompt in
Name in
Location
Default Value
Parameter
User Interface
FORTRAN Input
Limits
File
IFETAL
ifetal
Time Ind Phys
Params
1
Binary, 0 or 1
KWT
kwt
Time Ind Phys
Params
310
Must be
positive
PLSVOL
plsvol
Time Ind Phys
Params
30
Must be
positive
POWER
power
Time Ind Phys
Params
1.5
Must be
positive
RBCIN
rbcin
Time Ind Phys
Params
0.07
Must be
between 0
and 1
RBCNL
rbcnl
Time Ind Phys
Params
20
Must be
positive
RBCVOL
rbcvol
Time Ind Phys
Params
22
Must be
positive
RENIN
renin
Time Ind Phys
Params
0.01
Must be
between 0
and 1
RKDN1
rkdnl
Time Ind Phys
Params
0.139
Must be
positive
RLLI
rlli
Time Ind Phys
Params
1
Must be
positive
RLVR1
rlvrl
Time Ind Phys
Params
0.0693
Must be
positive
RPLAS
rplas
Time Ind Phys
Params
2000
Must be
positive
RPROT
rprot
Time Ind Phys
Params
0.139
Must be
positive
RSIC
rsic
Time Ind Phys
Params
6
Must be
positive
RSOFO
rsofO
Time Ind Phys
Params
2.079
Must be
positive
RSOF1
rsofl
Time Ind Phys
Params
0.00693
Must be
positive
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AALM v3.0 Users Guide
Parameter Prompt in
Name in
Location
Default Value
Parameter
User Interface
FORTRAN Input
File
Limits
RSOF2
rsof2
Time Ind Phys
Params
0.00038
Must be
positive
RSTMC
rstmc
Time Ind Phys
Params
24
Must be
positive
RULI
ruli
Time Ind Phys
Params
1.85
Must be
positive
S2HAIR
s2hair
Time Ind Phys
Params
0.4
Must be
between 0
and 1
SATRAT
satrat
Time Ind Phys
Params
350
Must be
positive
SIZEVF
sizevf
Time Ind Phys
Params
3
Must be
between 0
and 1
SOFIN
sofin
Time Ind Phys
Params
0.5
Must be
between 0
and 1
TBONEL
tbonel
Time Ind Phys
Params
0.08
Must be
between 0
and 1
TEVF
tevf
Time Ind Phys
Params
0.5
Must be
between 0
and 1
TOFECE
tofece
Time Ind Phys
Params
0.006
Must be
between 0
and 1
TOKDN1
tokdnl
Time Ind Phys
Params
0.025
Must be
between 0
and 1
TOKDN2
tokdn2
Time Ind Phys
Params
0.0004
Must be
between 0
and 1
TOLVR1
tolvrl
Time Ind Phys
Params
0.04
Must be
between 0
and 1
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AALM v3.0 Users Guide
Parameter Prompt in
Name in
Location
Default Value
Parameter
User Interface
FORTRAN Input
File
Limits
TOPROT
toprot
Time Ind Phys
Params
0.0004
Must be
between 0
and 1
TORBC
torbc
Time Ind Phys
Params
0.25
Must be
between 0
and 1
TOSWET
toswet
Time Ind Phys
Params
0.0035
Must be
between 0
and 1
TOURIN
tourin
Time Ind Phys
Params
0
Must be
between 0
and 1
TRBWT
trbwt
Time Ind Phys
Params
3000
Must be
positive
VBLC
vblc
Time Ind Phys
Params
0.067
Must be
positive
VKC
vkc
Time Ind Phys
Params
0.0085
Must be
positive
VLC
vie
Time Ind Phys
Params
0.025
Must be
positive
VLUC
vluc
Time Ind Phys
Params
0.015
Must be
positive
Media Parameters
After defining the configuration of Media, select "Go to
Media" to update the page with the defined selections.
PLEASE NOTE
Data other than that defined in the
Simulation Control tab and appearing in the
Media tab will not be included in the
simulation inputs for FORTRAN.
Binary switches (Yes/No) to include or exclude a
certain exposure media
These switches allow the user to easily include or exclude exposure from a given pathway (air,
dust, water, food, soil, and other). Please be aware that parameters other than those defined on
the simulation control tab will NOT be included in the simulation when inputs are defined for the
FORTRAN files (e.g., if data was entered on the Media tab for Soil, but the Soil pathway is
switched to "No" on Simulation Control tab before running simulation). Users must ensure
Simulation Control is accurate.
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AALM v3.0 Users Guide
Number of Sources
Sources can be used to model varied environments (or sources) of exposure. Each media is
allowed up to three different sources of exposure.
Examples of sources could be school, work, home, playgrounds, etc. These exposures can then
be turned on or off to mimic realistic exposure patterns using "masks" as outlined below.
The number of sources should be greater than zero if masks are to be used. However, if
sources is set equal to zero, when users select "Go to Media" all options for sources (i.e., 3) and
masks (i.e., 9) will appear.
After all sources are defined (i.e., active) and if no masks are applied, select "Go to Media" to
configure the page.
Time masks temporarily block or "turn
off" the exposure from the given source
from occurring during the desired time
period.
Number of Periodic "Time Masks"
Masks are used in simulations to temporarily "turn
off' exposure from a specific source. This process
temporarily turns off the source specified for the
defined length of time. Below is an example of
how masks could be used to assess high lead
concentrations in drinking water at a weekend camp. In this example Source 1 is the camp
exposure, which is "masked" (turned off, or blocked) 5 days of the week when the child is at
home or school. As setup in the example, exposure is turned off on days 2, 3, 4, 5, and 6 (i.e.,
first day blocked is 2 and the last day blocked is 6). Hence, the camp exposure source is only
active (i.e., turned on) during days 1 and 7. The days turned off by a mask are always within the
same period (e.g., 7 days for a week). Hence the "first day blocked" must be less than or equal
to the "last day blocked". Applying the mask correctly in the below example requires that the first
and last day blocked be consecutive days of the week (e.g., 1 and 2 or 6 and 7).
Media Sources, Intakes, and Relative Bioavailabilities
?
O
a
1 Masking Help 1
Reset
Done
RBA
RBA, Source 1
Clear Water
%eset Water
Concentration (ug/L)
Number of Ages
Ages (years)
0
5
18
3
Source 1
0
100
0
Mask#
Source
Period (days)
First day blocked
Last day
blocked
1
1
7
2
6
Intake
Number of Aqes
Aqes (years)
0
5
15
3
Intake (L/day)
0.2
0.3
0.35
Fraction, Source 1
1
1
1
Figure 2 - Screenshot of Water setup in Media tab
21
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AALM v3.0 Users Guide
Special use cases and additional examples of how to use these masks appropriately are
provided in the Appendix in Mask Examples.
Users may choose masks for any of their 3 sources per media. This tool allows for up to 9
masks per media type. Each mask is specific to one source.
For each of the media defined by the user, the following parameters are provided to FORTRAN.
Additionally, some parameters such as masks and concentrations are repeated as needed
provided by user inputs.
Filling in Media
After defining the configuration of the Media tab in
Simulation Control, define the number of ages
needed for both concentration of lead in the media
and intake. The Number of Ages is limited to 20.
Specific ages in this tab should be the minimum
age of 0 years and the age at which a parameter
will change value.
PLEASE NOTE
For recommended media concentrations
and intake rates as a function of age refer to
Appendix C of the Technical Support
Document (TSD) for the AALM v3.0. Users
may also refer to the AALM Example
Scenarios (Example 1 and 1a) in the
Appendix of this User Guide for defaults
related to the IEUBK model v2.0 for children.
The number of ages set by the user should
depend on how often the concentration or intake changes by age. This number should be each
time the value of the parameters will change throughout the simulation time. Keep in mind this is
across sources, so the number should be high enough to represent all the changes needed.
The first age should be the minimum age of the simulation followed by each age at which the
concentration or intake will change. If only one concentration is used (e.g., for soil or water), that
concentration only needs to be set for a single age starting of 0 years. The number of desired
changes in media intake rates can differ from the number of changes in concentration.
Table 6 - Parameters used in Media Tab
Parameter Prompt
Name in
Location
Default Value
Parameter
in User Interface
FORTRAN
Input File
Limits
Number of
sources
Simulation
0
Values allowed:
Sources
Control
0-3
Concentration:
Number of ages
conc_ages
Media
Varied
Maximum 100
ages can be
defined
Varied, site-
Must be positive
specific, refer to
Concentration (by
source and age)
cones#
Media
Appendix C of the
TSD for the
AALM v3.0 for
recommendations
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AALM v3.0 Users Guide
Parameter Prompt
in User Interface
Name in
FORTRAN
Input File
Location
Default Value
Parameter
Limits
Intake: Number of
ages
intake_ages
Media
Varied
Must be positive
Intake
intake_amt
Media
Varied, refer to
Appendix C of the
TSD for the
AALM v3.0 for
recommendations
Must be positive
Fraction
frac#
Media
1
Must be between
0 and 1;
Automatically set
to 1 when there
is only 1 source
Mask
mask#
Media
None
Four numbers
describing the
mask (source #,
period length
(days), first day
masked, last day
masked)
RBA
RBA
Media
Soil: 0.6*
Dust: 0.6 *
Water: 1
Air: 1
Food: 1
Other: No default
Relative
bioavailability of
each media
specific source
#, applied only to
fraction
transferred to Gl
tract.
* Default for smelter associated soil and dust Pb contamination.
Lung Parameters
This tab houses the parameters needed for FORTRAN to run a simulation with Air media. Users
are asked to update this data when Air is selected "Yes" on the Simulation Control tab.
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AALM v3.0 Users Guide
Table 7 - Lung Parameters
Parameter
Prompt in User
Interface
Name in
FORTRAN Input
File
Location
Default Value
Parameter
Limits
DepFracLET
DepFracLET
Lung
0.2
Must be between
0 and 1
DepFracLTB
DepFracLTB
Lung
0.159
Must be between
0 and 1
DepFracLalv
DepFracLalv
Lung
0.04
Must be between
0 and 1
RLETplas
RLETplas
Lung
7.68
Must be positive
RLETstom
RLETstom
Lung
0
Must be positive
RLTBplas
RLTBplas
Lung
1.94
Must be positive
RLTBLET
RLTBLET
Lung
0
Must be positive
RLalvPlas
RLalvPlas
Lung
0.347
Must be positive
RLalvLTB
RLalvLTB
Lung
0
Must be positive
RLalvLint
RLalvLint
Lung
0
Must be positive
RLintPlas
RLintPlas
Lung
0
Must be positive
As described in Section 2.3.3.1 of the Technical Support Document for the AALM v3.0, lung the
parameters in Table 7 and Figure 3 are for lung deposition, absorption, and elimination kinetics
are based on a study of human subjects. The subjects inhaled a clean (not excessively
carbonaceous due to a fuel rich mixture) automotive exhaust from combustion of fuel containing
203Pb-labeled tetraethyllead. The aerosol particles were reported to be 0.1 |jm and below. As
such, the lung kinetics (used in AALM v2.0 and v3.0) are most appropriate for near-ultrafine
(around 0.1 um in diameter) combustion aerosols. It is anticipated that a future version of the
AALM will offer guidance on particle deposition fractions for other sized aerosols and for the
lung kinetics parameters that are set to zero in AALM v3.0.
24
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AALM v3.Q Users Guide
Lung Parameters
X
Clear All
O
Reset
Done
Variable
Unit
Source 1
Description
DepFracLET
f
0.2
Fraction of inhaled air deposited in Extra-Thoracic region
DepFracLTB
f
0 159
Fraction of inhaled air deposited in Tracheo-Bronchial reqion
DepFracLalv
f
0.04
Fraction of inhaled air deposited in Alveolar reqion.
RLETplas
1/dav
7.68
Loss rate from Extra-Thoracic reqion to plasma.
RLETstom
1/dav
0
Loss rate from Extra-Thoracic reqion to Gl tract fstomach).
RLTBplas
1/dav
1.94
Loss rate from Tracheo-Bronchial reqion to plasma
RLTBLET
1/dav
0
Loss rate from Tracheo-Bronchial reqion to Extra-Thoracic reqion.
RLalvPlas
1/dav
0.347
Loss rate from Alveolar reqion to plasma.
RLalvLTB
1/dav
0
Loss rate from Alveolar reqion to Tracheo-Bronchial reqion
RLalvLint
1/dav
0
Loss rate from Alveolar reqion to Interstitial reqion.
RLintPlas
1/dav
0
Loss rate from Interstitial reqion to plasma.
Figure 3 - Lung Parameters screenshot
Switch to indicate solution type
The user can choose between "Forward" and "Solve for Allowable Concentration". Forward
solutions are calculated as normal with all the inputs feeding linearly into lead concentrations
(by tissue type) in the outputs. The Solve for Allowable Concentration option allows users to
calculate inputs iteratively to achieve the specified target BLL.
To run a Solve for Allowable Concentration simulation, make the selection on the Simulation
Control and return to the Media tab (at the top of the sheet) to update the parameters there.
When selecting "Solve for Allowable Concentration" a reminder will appear to help prompt the
user back to the Media tab to update these parameters. Confirm that there is only 1 source for
the specified media. If the background lead levels of the Allowable Concentration run are too
high to achieve the target BLL no outputs will be produced as there is no data appropriate for
the situation.
Table 8 - Model Options for Forward and Solve for Allowable Concentration Simulations
Parameter
Prompt in User
Interface
Name in
FORTRAN Input
File
Location
Default Value
Parameter
Limits
Solution type
iterate
Simulation
Control
Forward
Values specified
in drop down
menu
Media
media
Media
No default
Values specified
in drop down
menu
25
-------
AALM v3.0 Users Guide
Parameter
Prompt in User
Interface
Name in
FORTRAN Input
File
Location
Default Value
Parameter
Limits
Source
subtype
Media
No default
Values specified
in drop down
menu
Link Dust and
Soil?
Dustsoil
Media
No
Binary
Target BLL
targetbll
Media
No default
Must be positive
Precision
precision
Media
0.01
Must be positive
Metric
metric
Media
Arithmetic
Mean
Binary; Arithmetic
Mean or
Maximum value
for BLL
Age Width
agewidth
Media
No default
Must be positive
Age Min
agemin
Media
No default
Must be positive
Max Iteration
maxiter
Media
5
Must be positive
GSD
gsd
Media
1.6
Must be positive
Tail Fraction
tailfrac
Media
0.05
Must be between
0 and 1
The screenshot provided in Figure 4 illustrates the parameter setup to solve for the Pb
concentration in soil that will limit the probability to 5% for children (aged 1-6 years) from having
a blood lead that exceeds a target BLL of 5 |jg/dL. The metric is the arithmetic mean of
predicted blood Pb concentration over a five-year period starting when the hypothetical child
turns 1 year of age. Notice in Figure 4 that dust and soil concentrations are linked, whereas by
default they are not linked. This linkage means that the Pb concentration of soil and dust will be
increased or decreased by the same fraction of the originally entered concentrations until a
solution is reached. This solution is slightly different from the approach used in the Integrated
Exposure Uptake Biokinetic (IEUBK) model v2.0. If the IEUBK model v2.0 default "Multiple
source analysis" is used, the model calculates an indoor dust Pb concentration (jjg/g) that
equals 0.7 times the soil Pb concentration (jjg/g) plus 100 m3/g times the air Pb concentration
(|jg/m3). If users desire to solve for a soil Pb concentration in the same manner as the IEUBK
model, an equation can be entered into Cell F39 as =0.7*F12+100*F93 to solve for the dust Pb
concentration (Cell F39) as a function of the soil Pb concentration (Cell F12) and the air Pb
concentration (Cell F93). Users will need to run the solver function iteratively two or three times.
That is, after each run of the solver function, the user will enter the allowable soil Pb
concentration obtained by the solver into Cell F12 of the Media tab, then rerun the solver
function.
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AALM v3.0 Users Guide
Allowable Concentration Calculation Parameters
L:
;set Allowable | 0
ear Allowable
H
Media
Subtype
Link Dust and Soil?
Target BLL
Precision
Metric
Soil
Source 1
Yes
5
0.001
Arithmetic Mean
Age Width
(yr)
Age Min
(yr)
Max
Iteration
GSD
Tail
Fraction
5
1
8
1.6
0.05
Figure 4 - Screenshot of Setup for Allowable Concentration Solution
Switch to indicate stepwise or interpolated transitions between exposures
The Stepwise or Interpolated switch allows users to calculate changes in the sources of lead
exposure defined in Media in a stepwise manner or with linear interpolation between defined
concentrations for each age. In the stepwise approach the exposure concentrations remain
constant for the given age until defined for the next age, when they immediately change
according to user inputs. With the interpolated approach the exposure concentrations change
gradually over the given time period according to a linear formula between the concentrations at
the ages provided.
Table 9 - Stepwise or Interpolated Transitions for Exposure Intakes
Parameter
Prompt in User
Interface
Name in
FORTRAN
Input File
Location
Default Value
Parameter Limits
Stepwise or
Interpolated?
Interp
Simulation
Control
Stepwise
Binary; Stepwise
or Interpolated
Switch to indicate if red blood cell (RBC) should be linear or allow for
saturation
The RBC switch allows users to define if the red blood cell parameter should be calculated
linearly, or non-linearly which allows for saturation. For more information, see Section 2.3.4.3
(Red Blood Cells) in the Technical Support Document for the AALM v3.0.
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AALM v3.0 Users Guide
Table 10 - Choice of Linear or Nonlinear binding to RBC
Parameter
Prompt in User
Interface
Name in
FORTRAN
Input File
Location
Default Value
Parameter Limits
Linear or Non-
irbc
Simulation
Non-linear RBC
Binary; Linear or
linear RBC?
Control
Non-linear
3. Run the Model and Review the Results
Run Simulation
Figure 5 - Button to Run a Simulation
Finally, run the simulation by selecting Run Simulation please NOTE
(Figure 5) found at the bottom of the Simulation 0. , .. , , . . ....
. Simulation outputs are housed within
Control tab (Figure 1). The Excel file will create the parent ^rectory in a folder with the
text version of the input file, create a .xlsm of the input same name as the user-defined
file for user records, run the model, and import the simulation name,
results. If you have an error, ensure that the
executable file requested (32 or 64-bit) and User Interface (or GUI) are saved in the same
folder.
The outputs of the FORTRAN executables are written to a folder within the directory housing the
Excel GUI with the same name as the user provided simulation name. These files are:
• Day_[Simulation Name].csv
This output displays intake, uptake, and excretion data sums by day of the
simulation. This information is then displayed in the GUI in [Simulation
Name]_Daily. This data can be used for further analysis or could be read back
into the GUI for visualization using the "Import" button on the Explore Data tab.
• [Simulation Name]_Fortranlnput.xlsm
This output serves as a record of the inputs of the simulation provided to
FORTRAN. Values that deviate from the default are bolded and highlighted for
the user in yellow.
• Leggettlnput.txt The import buttons on the Simulation
This output serves as a secondary Control and Explore Data tabs allow users to
record of the inputs provided to load previously run inputs back into the GUI
FORTRAN that could be used to or ana|Vze Previously run data,
manually re-run the simulation if needed by replacing the file of the same name
in the parent directory and opening the FORTRAN executable or could be read
back into the GUI using the "Import" button on the Simulation Control tab.
• Log_[Simulation Name].csv
This output serves as a full log of the source data at each timestep.
• Out_[Simulation Name].csv
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AALM v3.0 Users Guide
This output displays concentration and mass data sums by tissue for each user-
defined output timestep. This information is then displayed in the GUI in
[Simulation Name]_Output.
• Src_[Simulation Name].csv
This output displays the source defined exposure data (including total lead
intake, body burden, and amount eliminated) by each user-defined output
timestep.
• Runlnfo_[Simulation Name].csv
This output displays information about the simulation especially when the
simulation solves for an allowable concentration. When that selection is chosen
this file is used by the GUI to display the calculated allowable concentrations.
These outputs are then imported into the GUI and displayed or summarized in the following
tabs:
• Output Summary: Acts as a menu to access outputs and displays allowable
concentration data as applicable.
• Explore Data: Presents data visualizations and allows for blood lead exceedance
calculations.
• Detailed Outputs: Presents user-defined timestep-level data from the model.
• Daily: Presents data from the model at a daily interval.
Output Summary
This tab houses basic analysis of the simulation and directs the user to the two raw output files
imported into the GUI. This tab has five buttons for users to select:
• General Run Information
This button displays brief summary data of the
simulation such as the runtime and duration,
simulation timespan, type of run, and an
indication of any errors or warnings
encountered.
• Detailed Outputs by Timestep
This button takes the user directly to Detailed
Outputs, described below.
• Daily Intake and Uptake Values
This button takes the user directly to Daily,
described below.
• Explore Data
This button takes the user directly to the
Explore Data tab, described below.
• Allowable Concentration
If the solution type was a Solve for Allowable Concentration, the button displays
the Solve for Allowable Concentration input data, along with the solution of when
the target BLL was reached in the user-defined Media.
Output Selection
Figure 6 - Output Section
Screenshot
29
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AALM v3.0 Users Guide
PLEASE NOTE
Throughout the GUI, yellow fields indicate
cells which should be altered by the user.
The white fields will calculate automatically
based on these updates.
Select Data Summaries to View
P" Blood Lead ((jg/dL)
W Plasma Lead (pg/dL)
P" Cortical Bone Lead (gg/g)
p"Trabecular Bone Lead (pg/g)
P" Cortical Bone Lead Mass ftjg)
P"Trabecular Bone Lead Mass (pg)
P" Gastrointestinal Lead Intake (pg/day)
Figure 7 - Graphs that Users may
Select to Display
Explore Data
Before analyzing and visualizing data in Explore
Data, update the page to ensure the data from the
simulation name defined on the Simulation Control
page is displayed. To display previously run
simulation data, the "Import" buttons on the
Simulation Control and Explore Data tabs can be
used to import inputs and results of previously run
scenarios, respectively.
In the Explore Data tab, users can select which
data summaries are most valuable for them in
their analysis by selecting each desired data
summary with the check boxes to the left of each
compartment.
As in the rest of the GUI, yellow cells indicate
fields which should be updated or altered by the
user. The white fields will calculate automatically
based on these updates.
For each data summary, the GUI calculates:
• Compartment-specific lead statistics, for a user-defined age range
o Percent exceedance of the average, for a user-defined limit and geometric
standard deviation (GSD)
• Compartment-specific lead values, for a user-defined age
o Percent exceedance at the user-defined age, for a user-defined limit and
geometric standard deviation (GSD)
• Compartment-specific Area under the curve (AUC), for a user-defined age range
Uses of these parameters may vary depending on the reason for the simulation, but in general,
the calculations of age-defined exposure values are expected to be useful for those users which
may be performing site-specific risk assessments or otherwise assessing risk. The AUC value
may be useful in calculation of a time-weighted average for each compartment.
Further, the x- and y- axes of the graphs can be altered to view a smaller portion of the graph in
greater detail as desired.
Detailed Outputs
This tab displays the output data as defined in the advanced time options and base parameters.
Each output field (described below) is quantified at each timestep as defined by the user. These
timesteps are then calculated into days and years to aid the user with analysis.
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AALM v3.0 Users Guide
Table 11 - Output Parameters Displayed on the Detailed Outputs Tab
Variable
Data description
timestep
Timestep number, with 0 being the start of the simulation
days
Age in days since birth
years
Age in decimal years since birth (=age/365)
Cblood
Total Blood Pb concentration (BLL)
Cplas
Blood plasma Pb concentration
Ckidney
Kidney Pb concentration
Cliver
Liver Pb concentration
Ccort
Cortical bone Pb concentration
Ctrab
Trabecular bone Pb concentration
Cbone
Total bone Pb concentration
Ablood
Pb mass in blood (plamsa + RBC). Same as in original Leggett code,
this does not include plasma-protein Pb.
Aplas
Pb mass in plasma
ARBC
Pb mass in red blood cells (RBC)
Akidney
Pb mass in kidneys
Aliver
Pb mass in liver
Acort
Pb mass in cortical bone
Atrab
Pb mass in trabecular bone
Abone
Pb mass in bone (sum of P+Q)
Asoft
Pb mass in soft tissue (sum of 3 tissue types)
Abrain
Pb mass in brain
ART
Pb mass in lungs (sum over compartments)
Astom
Pb mass in stomach
AGI
Pb mass in Gl tract (sum of SI, ULI, LLI)
Aprot
Pb mass in protein-bound plasma
AEVF
Pb mass in extra-vascular fluid (EVF)
Ablad
Pb mass in bladder
Aflow
Pb mass traveling between compartments
Tbody
Total Pb mass in body
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AALM v3.0 Users Guide
Variable
Data description
Aurine
Total Pb mass excreted via urine (summed over time)
Afecal
Total Pb mass lost via feces (summed over time)
Asweat
Total Pb mass lost via sweat (summed over time)
Ahair
Total Pb mass lost to hair (summed over time)
Daily
This tab displays output parameters summarized as daily values for intake, uptake, and
excretion for each media.
Table 12 - Output Parameters Displayed on the Daily Tab
Variable
Data description
InAirTot
Total Pb mass inhaled (summed over each day)
InAirDep
Total inhaled Pb mass deposited (summed over each day). This variable
is currently only showing deposition in the ET region, not TB or PU.
Inlngest
Total ingested Pb mass (summed over each day)
InDust
Total Pb mass from dust ingestion (summed over each day)
InSoil
Total Pb mass from soil ingestion (summed over each day)
In Water
Total Pb mass from water ingestion (summed over each day)
InFood
Total Pb mass from food ingestion (summed over each day)
InOther
Total Pb mass from other ingestion (summed over each day)
UpTotal
Total Pb uptake in plasma (summed over each day)
UpAir
Total Pb plasma uptake from air (summed over each day)
UpLung
Total Pb plasma uptake in lungs (summed over each day)
UpGIAir
Total Pb plasma uptake from air in Gl tract (summed over each day)
UpGITotal
Total Pb plasma uptake in Gl tract (summed over each day)
Uplngest
Total Pb plasma uptake from ingestion (summed over each day)
UpGIDust
Total Pb plasma uptake from dust (summed over each day)
UpGISoil
Total Pb plasma uptake from soil (summed over each day)
UpGIWater
Total Pb plasma uptake from water (summed over each day)
UpGIFood
Total Pb plasma uptake from food (summed over each day)
UpGIOther
Total Pb plasma uptake from other (summed over each day)
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AALM v3.0 Users Guide
Variable
Data description
ExAir
Total inhaled Pb not deposited in lungs (summed over each day)
Exllrine
Total Pb mass excreted in urine (summed over each day)
ExFeces
Total Pb mass excreted in feces (summed over each day)
ExSweat
Total Pb mass excreted in sweat (summed over each day)
ExHair
Total Pb mass excreted in hair and nails (summed over each day)
4. QA Step: Confirm the Intake Results Give the Correct Time
Series
As a final QA step, the user is encouraged to inspect the output and verify that the intake time-
varying profiles match what was intended. Remember that if the simulation exposure is varied
over a very brief time period but the output interval was longer than that time period, the actual
intake change won't be recorded in the output (e.g., an exposure from age 1.25 to 1.75, but
outputs only saved every year).
IV. Troubleshooting
Table 13 - Troubleshooting Questions and Answers
Question
Answer
Setup
I'm having trouble getting
the model to run.
Ensure all the files from the zip file are in the same folder
and none have been deleted. If needed unzip the original
file again and export the original files.
My Media tab isn't set up the
way 1 defined it in Simulation
Control.
Navigate to the Media tab through "Go to Media" this will
update the formatting of the tab.
Running AALM
Some of my data isn't
populating.
Check the Simulation Control. Any data outside the
parameters set in this tab are ignored when writing the input
files for FORTRAN.
Reviewing the Results
Where are my output files?
Outputs and a copy of the FORTRAN inputs for the run are
written to a folder with the same simulation name within the
folder housing the GUI.
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Question
Answer
My Explore Data tab looks
like it has old data.
Before using, select "update" at the top of Explore Data to
ensure the data has updated to the run name specified on
Simulation Control.
The output file is blank but
the daily file generated
correctly.
If an allowable concentration run results in background lead
too high to reach the target BLL, there are not results to
show, so they are not displayed in the GUI but the files are
still generated.
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AALM v3.0 Users Guide
V. Appendix
The sections in this appendix are meant to serve as a reference sheet for users to summarize
the user-defined parameters in this tool as well as give more instruction to users about how to
implement various scenarios.
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Default Values
Table 14 - Default Model Values
Parameter
Prompt in User
Interface
Name in
FORTRAN
Input File
Location
Default Value
Parameter Limits
Description
Timesteps per
day
steps_per_day
Simulation
Control
100
Cannot exceed 12
when using the 32-
bit executable
Number of times lead loading and
distribution should be calculated in
the simulation each day
Timesteps
between outputs
outwrite
Simulation
Control
100
Must be positive
Frequency of output written
containing lead loading and
distribution calculations
Age at start (yrs)
age_range
Simulation
Control
0- Not
accessible for
change by users.
Must not be greater
than 0 and must be
less than "Age at
end"
Age of the simulated individual at
the start of the simulation
Age at end (yrs)
age_range
Simulation
Control
90
Must not exceed
100 and must be
greater than "Age at
start". Cannot
exceed 8 years
when using the 32-
bit executable.
Age of the simulated individual at
the end of the simulation
Sex
sex
Simulation
Control
Female
Binary; Female or
Male
Sex of the simulated individual
wbirth
wbirth
Growth
Params
3.3
Must be positive
Weight at birth
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AALM v3.0 Users Guide
wchild
wchild
Growth
Params
22
Must be positive
Maximum weight for early hyperbolic
growth period
half
half
Growth
Params
3
Must be positive
Age at which weight is half WCHILD
wadult
wadult
Growth
Params
34
Must be positive
Maximum weight for logistic growth
period
kappa
kappa
Growth
Params
600
Must be positive
Logistic constant kappa
lambda
lambda
Growth
Params
0.017
Must be greater
than 0
Logistic constant lambda
LB
LB
Growth
Params
0.85
Must be between 0
and 1
Ratio of lean body mass to body
mass
ASHWT
ashwt
Time Ind
Phys
Params
2800
Not used
Skeletal ash weight
BLDMOT
bldmot
Time Ind
Phys
Params
0.62
Must be positive
Maternal blood lead concentration
BONIN
bonin
Time Ind
Phys
Params
0.32
Must be between 0
and 1
Fraction of body lead, at birth, in
bone
BRANIN
branin
Time Ind
Phys
Params
0.045
Must be between 0
and 1
Fraction of body lead, at birth, in
brain
BRATIO
bratio
Time Ind
Phys
Params
0.85
Must be between 0
and 1
Fetal: maternal blood lead
concentration ratio
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AALM v3.0 Users Guide
CRTWT
crtwt
Time Ind
Phys
Params
4000
Must be positive
Cortical bone weight
H1T0BL
hltobl
Time Ind
Phys
Params
0.45
Must be between 0
and 1
Fraction of transfer out of liver
compartment 1 that goes to
diffusible plasma
H1T0H2
h1toh2
Time Ind
Phys
Params
0.1
Must be between 0
and 1
Fraction of transfer out of liver
compartment 1 that goes to liver
compartment 2
H1T0SI
hltosi
Time Ind
Phys
Params
0.45
Must be between 0
and 1
Fraction of transfer out of liver
compartment 1 that goes to the
small intestine
HCTA
hcta
Time Ind
Phys
Params
0.41
Must be between 0
and 1
Adult hematocrit (sex dependent)
HCTB
hctb
Time Ind
Phys
Params
0.52
Must be between 0
and 1
Birth hematocrit
HEPIN
hepin
Time Ind
Phys
Params
0.055
Must be between 0
and 1
Fraction of body lead, at birth, in
liver
IFETAL
ifetal
Time Ind
Phys
Params
1
Binary, 0 or 1
Switch for starting tissue Pb from
maternal blood (1)
KWT
kwt
Time Ind
Phys
Params
310
Must be positive
Adult kidney weight
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AALM v3.0 Users Guide
PLSVOL
plsvol
Time Ind
Phys
Params
30
Must be positive
Plasma volume
POWER
power
Time Ind
Phys
Params
1.5
Must be positive
Exponent for RBC deposition
RBCIN
rbcin
Time Ind
Phys
Params
0.07
Must be between 0
and 1
Fraction of body lead, at birth, in red
blood cells
RBCNL
rbcnl
Time Ind
Phys
Params
20
Must be positive
Threshold concentration in RBC for
non-linear deposition from diffusible
plasma to RBC
RBCVOL
rbcvol
Time Ind
Phys
Params
22
Must be positive
Red blood cell volume
RENIN
renin
Time Ind
Phys
Params
0.01
Must be between 0
and 1
Fraction of body lead, at birth, in
kidney
RKDN1
rkdnl
Time Ind
Phys
Params
0.139
Must be positive
Transfer rate from kidney
compartment 1 to urinary pathway
RLLI
rlli
Time Ind
Phys
Params
1
Must be positive
Transfer rate from lower large
intestine to feces
RLVR1
rlvrl
Time Ind
Phys
Params
0.0693
Must be positive
Transfer rate out of the liver
compartment 1, including to small
intestine and diffusible plasma
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AALM v3.0 Users Guide
RPLAS
rplas
Time Ind
Phys
Params
2000
Must be positive
Total transfer rate from diffusible
plasma to all compartments
RPROT
rprot
Time Ind
Phys
Params
0.139
Must be positive
Transfer rate from bound plasma to
diffusible plasma
RSIC
rsic
Time Ind
Phys
Params
6
Must be positive
Transfer rate from small intestine to
upper large intestine
RSOFO
rsofO
Time Ind
Phys
Params
2.079
Must be positive
Transfer rate from soft tissue
compartment 0 to diffusible plasma
RSOF1
rsofl
Time Ind
Phys
Params
0.00693
Must be positive
Transfer rate from soft tissue
compartment 1 to diffusible plasma
RSOF2
rsof2
Time Ind
Phys
Params
0.00038
Must be positive
Transfer rate from soft tissue
compartment 2 to diffusible plasma
RSTMC
rstmc
Time Ind
Phys
Params
24
Must be positive
Transfer rate from stomach to small
intestine
RULI
ruli
Time Ind
Phys
Params
1.85
Must be positive
Transfer rate from upper large
intestine to lower large intestine
S2HAIR
s2hair
Time Ind
Phys
Params
0.4
Must be between 0
and 1
Deposition fraction from soft tissue
compartment 1 to other excreta
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AALM v3.0 Users Guide
SATRAT
satrat
Time Ind
Phys
Params
350
Must be positive
Maximum (saturating) concentration
of lead in RBC
SIZEVF
sizevf
Time Ind
Phys
Params
3
Must be between 0
and 1
Relative volume of the EVF
compartment compared to plasma
(EVF/Plasma)
SOFIN
sofin
Time Ind
Phys
Params
0.5
Must be between 0
and 1
Fraction of body lead, at birth, in soft
tissue
TBONEL
tbonel
Time Ind
Phys
Params
0.08
Must be between 0
and 1
End value of TBONE-age array
TEVF
tevf
Time Ind
Phys
Params
0.5
Must be between 0
and 1
Deposition fraction from diffusible
plasma to extravascular fluid
TOFECE
tofece
Time Ind
Phys
Params
0.006
Must be between 0
and 1
Deposition fraction from diffusible
plasma directly to the small intestine
(not including the transfer from
biliary secretion, specified by
RLVR1)
TOKDN1
tokdnl
Time Ind
Phys
Params
0.025
Must be between 0
and 1
Deposition fraction from diffusible
plasma to kidney compartment 1
TOKDN2
tokdn2
Time Ind
Phys
Params
0.0004
Must be between 0
and 1
Deposition fraction from diffusible
plasma to kidney compartment 2
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AALM v3.0 Users Guide
T0LVR1
tolvrl
Time Ind
Phys
Params
0.04
Must be between 0
and 1
Deposition fraction from diffusible
plasma to liver compartment 1
TOPROT
toprot
Time Ind
Phys
Params
0.0004
Must be between 0
and 1
Deposition fraction from diffusible
plasma to protein-bound plasma
TORBC
torbc
Time Ind
Phys
Params
0.25
Must be between 0
and 1
Deposition fraction from diffusible
plasma to red blood cells, below
non-linear threshold
TOSWET
toswet
Time Ind
Phys
Params
0.0035
Must be between 0
and 1
Deposition fraction from diffusible
plasma to sweat
TOURIN
tourin
Time Ind
Phys
Params
0
Must be between 0
and 1
Deposition fraction from diffusible
plasma to urine
TRBWT
trbwt
Time Ind
Phys
Params
3000
Must be positive
Trabecular bone weight
VBLC
vblc
Time Ind
Phys
Params
0.067
Must be positive
Total blood volume
VKC
vkc
Time Ind
Phys
Params
0.0085
Must be positive
Kidney volume in the adult
VLC
vie
Time Ind
Phys
Params
0.025
Must be positive
Liver volume in the adult
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AALM v3.0 Users Guide
VLUC
vluc
Time Ind
Phys
Params
0.015
Must be positive
Lung volume in adult
F1
f1
Time Dep
Phys
Params
Varied
Must be between 0
and 1
Gl-tract absorption fraction which
are applied to Pb ingested from all
sources, (based on Leggett 1993)
AMTBLD
amtbld
Time Dep
Phys
Params
Varied
Must be positive
Age-scaled amount of blood
FLONG
flong
Time Dep
Phys
Params
0.6
Must be between 0
and 1
Age-scaled fraction of total transfer
from the exchangeable bone
directed to non-exchangeable bone
GSCAL
gscal
Time Dep
Phys
Params
Varied
Not used
Age scaling factor for GIT transfer
RBLAD
rblad
Time Dep
Phys
Params
Varied
Must be positive
Age-scaled transfer rate from
urinary bladder to urine
RBRAN
rbran
Time Dep
Phys
Params
0.00095
Must be positive
Age-scaled transfer rate from brain
to diffusible plasma
RCORT
rcort
Time Dep
Phys
Params
Varied
Must be positive
Age-scaled transfer rate from non-
exchangeable cortical bone to
diffusible plasma
RCS2B
rcs2b
Time Dep
Phys
Params
Varied
Must be positive
Age-scaled transfer rate from
cortical bone surface to diffusible
plasma
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RCS2DF
rcs2df
Time Dep
Phys
Params
Varied
Must be positive
Age-scaled transfer rate from
cortical bone surface to
exchangeable cortical bone
RDIFF
rdiff
Time Dep
Phys
Params
0.023105
Must be positive
Age-scaled transfer rate from the
exchangeable bone, including
transfer to surface and non-
exchangeable bone
RKDN2
rkdn2
Time Dep
Phys
Params
Varied
Must be positive
Age-scaled transfer rate from kidney
compartment 2 to diffusible plasma
RLVR2
rlvr2
Time Dep
Phys
Params
Varied
Must be positive
Age-scaled transfer rate from the
slow liver compartment 2 to
diffusible plasma
RRBC
rrbc
Time Dep
Phys
Params
Varied
Must be positive
Age-scaled transfer rate from red
blood cell to diffusible plasma
RTRAB
rtrab
Time Dep
Phys
Params
Varied
Must be positive
Age-scaled transfer rate from non-
exchangeable trabecular bone to
diffusible plasma
RTS2B
rts2b
Time Dep
Phys
Params
Varied
Must be positive
Age-scaled transfer rate from
trabecular bone surface to diffusible
plasma
RTS2DF
rts2df
Time Dep
Phys
Params
Varied
Must be positive
Age-scaled transfer rate from
surface trabecular bone to
exchangeable trabecular bone
TBONE
tbone
Time Dep
Phys
Params
Varied
Must be between 0
and 1
Age-scaled deposition fraction from
diffusible plasma to surface bone
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AALM v3.0 Users Guide
TFRAC
tfrac
Time Dep
Phys
Params
Varied
Must be between 0
and 1
Bone deposition-scaled fraction of
diffusible plasma-to-bone deposition
that goes to trabecular surface
bone; 1-TFRAC is the fraction that
goes to cortical surface bone.
TOBRAN
tobran
Time Dep
Phys
Params
Varied
Must be between 0
and 1
Age-scaled deposition fraction from
diffusible plasma to brain
TOSOFO
tosofO
Time Dep
Phys
Params
Varied
Must be between 0
and 1
Age-scaled deposition fraction from
diffusible plasma to soft tissue
compartment 0
TOSOF1
tosofl
Time Dep
Phys
Params
Varied
Must be between 0
and 1
Age-scaled deposition fraction from
diffusible plasma to soft tissue
compartment 1
TOSOF2
tosof2
Time Dep
Phys
Params
0.001
Must be between 0
and 1
Age-scaled deposition fraction from
diffusible plasma to soft tissue
compartment 2
Number of
Sources
sources
Simulation
Control
0
Values allowed: 0-3
Sources of lead exposure per each
type of media (ie. soil, dust etc.)
Concentration:
Number of ages
conc_ages
Media
Varied
Maximum 100 ages
can be defined
Number of ages at which the user
wishes to define lead concentration
for the given sources; concentration
should be defined each time the
concentration will change for each of
the sources defined
Concentration
(by source and
age)
cones#
Media
see Appendix C
of the TSD for the
AALM v3.0
Must be positive
Lead concentration to be simulated
by each source varied by age as
needed
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Intake: Number
of ages
intake_ages
Media
Varied
Must be positive
Number of ages at which the user
wishes to define intake for the given
sources; intake should be defined
each time the concentration will
change for each of the sources
defined
Intake
intake_amt
Media
Varied. See
Appendix Table
Media Source
Intake Values by
Age
Must be positive
Intake of the given media to be
simulated by each source varied by
age as needed
Fraction
frac#
Media
1
Must be between 0
and 1; Automatically
set to 1 when there
is only 1 source
Fraction of exposure of each source
in intake
Mask
mask#
Media
None
Four numbers
describing the mask
(source #, period
length (days), first
day masked, last
day masked)
A period of temporary period of non-
exposure from a given lead source
RBA
RBA
Media
Soil: 0.6*
Dust: 0.6 *
Water: 1
Air: 1
Food: 1
Other: No default
Must be positive
Relative bioavailability of each
media specific source #, applied
only to fraction transferred to Gl
tract
DepFracLET
DepFracLET
Lung
0.2
Must be between 0
and 1
Fraction of inhaled air deposited in
Extra-Thoracic region.
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DepFracLTB
DepFracLTB
Lung
0.159
Must be between 0
and 1
Fraction of inhaled air deposited in
Tracheo-Bronchial region.
DepFracLalv
DepFracLalv
Lung
0.04
Must be between 0
and 1
Fraction of inhaled air deposited in
Alveolar region.
RLETplas
RLETplas
Lung
7.68
Must be positive
Loss rate from Extra-Thoracic region
to plasma.
RLETstom
RLETstom
Lung
0
Must be positive
Loss rate from Extra-Thoracic region
to Gl tract (stomach).
RLTBplas
RLTBplas
Lung
1.94
Must be positive
Loss rate from Tracheo-Bronchial
region to plasma.
RLTBLET
RLTBLET
Lung
0
Must be positive
Loss rate from Tracheo-Bronchial
region to Extra-Thoracic region.
RLalvPlas
RLalvPlas
Lung
0.347
Must be positive
Loss rate from Alveolar region to
plasma.
RLalvLTB
RLalvLTB
Lung
0
Must be positive
Loss rate from Alveolar region to
Tracheo-Bronchial region.
RLalvLint
RLalvLint
Lung
0
Must be positive
Loss rate from Alveolar region to
Interstitial region.
RLintPlas
RLintPlas
Lung
0
Must be positive
Loss rate from Interstitial region to
plasma.
Solution type
iterate
Simulation
Control
Forward
Values specified in
drop down menu
Switch indicating if the simulation
should use forward calculation or
solve for an allowable concentration
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Media
media
Media
No default
Values specified in
drop down menu
Media source of lead to be used in
allowable concentration calculation
Source
subtype
Media
No default
Values specified in
drop down menu
Switch indicating if concentration of
lead should be linearly interpolated
between user defined values or
stepwise in calculation
Link Dust and
Soil?
Dustsoil
Media
No
Binary
Switch indicating is red blood cells
should be linear or non-linear
(allowing for saturation)
Target BLL
targetbll
Media
No default
Must be positive
Target BLL to solve for
Precision
precision
Media
0.01
Must be positive
Allowable variation from the BLL
Metric
metric
Media
Arithmetic Mean
Binary; Arithmetic
Mean or Maximum
value for BLL
Calculation method to solve for
target BLL
Age Width
agewidth
Media
No default
Must be positive
The number of simulation days to
calculate BLL over
Age Min
agemin
Media
No default
Must be positive
Starting age of target BLL
calculation
Max Iteration
maxiter
Media
5
Must be positive
Maximum number of interations
used to calculate if target BLL is
reached
GSD
gsd
Media
1.6
Must be positive
Assumed geometric standard
deviation of the assumed lognormal
distribution of BLL
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Tail Fraction
tailfrac
Media
0.05
Must be between 0
and 1
Fraction of the lognormal distribution
in the tail
Stepwise or
Interpolated?
interp
Simulation
Control
Stepwise
Binary; Stepwise or
Interpolated
Switch indicating if concentration of
lead should be linearly interpolated
between user defined values or
stepwise in calculation
Linear or Non-
linear RBC?
irbc
Simulation
Control
Non-linear RBC
Binary; Linear or
Non-linear
Switch indicating is red blood cells
should be linear or non-linear
(allowing for saturation)
* Default for smelter associated soil and dust Pb contamination.
49
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Mask Examples
Below are some examples of scenarios which were modeled with previous versions of AALM
and how they might be implemented with this current system of masking.
Please note that the masking logic as currently implemented acts in a negative way, blocking
sources in a regular periodic manner. The specific examples are more amenable to a positive
"windowing" logic, where the sources are active only during the specified intervals. This
process may be implemented on future iterations of AALM.
The current system allows multiple masks to be applied to the same source. If any mask is
active the source is blocked.
Example 1: Children's camping over several years
Allow 2 weeks of exposure each summer from ages 10 to 18 years inclusive.
There are two ambiguous points here. First, the simulation could simply begin at age 10 and
end when the person turns 19. Then the age range is automatically accounted for. The second
point is that there is no seasonality in the simulation, except perhaps in the sources. Age is a
matter of time since birth, and people can be born at any time of the year.
Suppose the simulation is over a lifetime and the person is assumed to be born in the summer.
Turn on the camping source exposure (0.5 |jg/g) when age 10 is reached (3650 days) and off
after the age 18 exposure ends (say, 9*365 days later). Although the soil Pb concentration of
0.5 |jg/g will not cause a noticeable change in blood Pb concentration, 500 |jg/g would. Use
stepwise so the source turns on and off abruptly. The mask has period 365 days because it
repeats annually. It blocks all but the first 14 days of each year, for example:
Soil, maskl, 4, 1, 365, 15, 365
I Soil
Reset Soil
Clear Soil
Concentration (ug/g)
Number of Ages
Ages (years)
0
10
19
3
Source 1
0
0.5
0
Mask#
Source
Period (days)
First day blocked
Last day
blocked
1
1
365
15
365
Intake
Number of Aqes
Aqes (years)
0
0.25
2
Intake (q/day)
0.018
0032
Fraction, Source 1
1
1
|RBA I RBA. Source 1 I 0.6
Figure 8 - Screenshot 1 for Applying Masks to Camping Scenario
This says that the mask applies to soil source #1 (the number after the "4", which is the number
of values to be read from the row), has a period of 365 days, and starts on day 15 and ends on
day 365 of each period.
Alternatively, the mask could exclude all but the last 14 days of the year as follows:
Soil, maskl, 4, 1, 365, 1, 351
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AALM v3.0 Users Guide
Soil
Reset Soil
Clear Soil
Concentration (ug/g)
Number of Ages
Ages (years)
0
10
19
3
Source 1
0
0.5
0
Mask#
Source
Period (days)
First day blocked
Last day
blocked
1
1
365
1
351
Intake
Number of Aqes
Aqes (years)
0
0.25
2
Intake (q/dav)
0.018
0.032
Fraction, Source 1
1
1
RBA
RBA, Source 1
0.6
Figure 9 - Screenshot 2 for Applying Masks to Camping Scenario
To make the exposure time in the middle of the year is more difficult because two masks are
needed: one to exclude the days before camping and the other for the days after, for example:
Soil, mask"!, 4, 1, 365, 1, 180
Soil, mask2, 4, 1, 365, 195, 365
Soil
Reset Soil
Clear Soil
Concentration (ug/g)
Number of Ages
Ages (years)
0
10
19
3
Source 1
0
0.5
0
Mask#
Source
Period (days)
First day blocked
Last day
blocked
1
1
365
1
180
2
1
365
195
365
Intake
Number of Aqes
Aqes (years)
0
025
2
Intake (q/day)
0.018
0032
Fraction, Source 1
1
1
RBA
RBA, Source 1
0.6
Figure 10 - Screenshot 3 for Applying Masks to Camping Scenario
This allows the source to operate on days 181 through 194 inclusive, each year.
Example 2: Youth summer day camp exposures from 6 to 19 years inclusive
Allow 8 weeks (excluding weekends) of exposure from age 6-19 (inclusive).
This is similar to example 1 except that the exposure is interrupted each week to exclude
weekends. Although the soil Pb concentration of 0.5 |jg/g will not cause a noticeable change in
blood Pb concentration, 500 |jg/g would. Turn the source on when the child reaches age 6
(6*365 days) and off 13 years later. Two masks are needed, one with a period of 365 days to
create the annual repetitions and the other with a period of 7 days to create the weekly pattern.
Again, there is flexibility in when the day camp starts relative to the child's birthday. If it runs for
the last 8 weeks that they are 6 years old, then the following works:
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AALM v3.0 Users Guide
Soil, maskl, 4, 1, 365, 1, 309
Soil, mask2, 4, 1, 7, 6, 7
Soil
Reset Soil
Clear Soil
Concentration (ug/g)
Number of Ages
Ages (years)
0
6
20
3
Source 1
0
0.5
0
Mask#
Source
Period (days)
First day blocked
Last day
blocked
1
1
365
1
309
2
1
7
6
7
Intake
Number of Aqes
Aqes (years)
0
0.25
2
Intake (g/day)
0.018
0.032
Fraction, Source 1
1
1
|RBA | RBA. Source 1 | 0.6
Figure 11 - Screenshot for Applying Masks to Summer Camp Scenario
Both masks apply to the same source (the "1" after the "4"). The first mask blocks all but the last
56 days of each year. The second mask blocks days 6 and 7 of each week. The result is 8
weeks of 5 days exposure each week, repeating each year for 13 consecutive years.
Example 3: Dietary Supplements taken on regular schedule
Allow intake of dietary supplement on a daily basis from age 1 on.
This is a food intake, for which AALM requires input in total Pb/day (not separated into a product
of food mass consumed and Pb concentration of food). In this example, only the mass of Pb in
the dietary supplement is illustrated. Set up a constant source of the appropriate mass of lead
consumed per day (corresponding to an intake of 1 tsp of supplement per day), starting at the
age when the supplement is first administered. For this scenario it is assumed that a teaspoon
of supplement has a mass of 5 grams and that the lead concentration in the supplement is 1.4
ppm, which gives a daily intake of 7 |jg. Then mask it as follows in each of the cases:
a) 2 consecutive days per week:
¦ food, maskl, 4, 7, 3, 7
Food
Clear Food
Reset Food
1
Intake (ug/day)
Number of Ages
Ages (years)
0
2
2
Source 1
0
7
Mask#
Source
Period (days)
First day blocked
Last day
blocked
1
1
7
3
7
[RBA I RBA. Source 1 I 0.6 I
Figure 12 - Screenshot 1 for Applying Masks to an Adulterated Dietary Supplement
b) 2 non-consecutive days per week:
¦ food, maskl, 4, 7, 2, 3 and food, mask2, 4, 7, 5, 7
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AALM v3.0 Users Guide
Food
Clear Food
Reset Food
1
Intake (ug/day)
Number of Ages
Ages (years)
0
2
2
Source 1
0
7
Mask#
Source
Period (days)
First day blocked
Last day
blocked
1
1
7
2
3
2
1
7
5
7
RBA
RBA, Source 1
0.6
Figure 13 - Screenshot 2 for Applying Masks to an Adulterated Dietary Supplement
c) 2/7 tsp every day:
¦ No mask, just lower the source to 2/7 of above (i.e., 2 |jg).
Food
Clear Food ^
Reset Food
1
Intake (ug/day)
Number of Ages
Ages (years)
0
2
2
Source 1
0
2
I RBA
RBA, Source 1
0.6
Figure 14 - Screenshot 3 for Alternative to Masks to an Adulterated Dietary
Supplement
Example 4: Therapeutic home remedies
This would count as "other" media, which like food uses total Pb ingested per day without
separating it into mass and concentration. Determine the Pb intake per day from this source
and set up a constant source at that level.
a) 7 days per week for days 60 to 120 after the 20th birthday.
¦ Set up the source to start at age 20.16 (i.e., 20+60/365) and end at 20.33 (i.e.,
20+120/365), using stepwise (Cell E34 of the Simulation Control tab). No mask
needed.
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AALM v3.0 Users Guide
Media Sources, Intakes, and Relative Bioavailabilities
?
O
I Masking Help 1
Reset
Done
Intake (ug/day)
Number of Ages
Ages (years)
0
20.16
20.33
3
Source 1
0
0.5
0
RBA
RBA, Source 1
Figure 15 - Screenshot for Adulterated Therapeutic Home Remedies Scenario
b) 1 pill on 1 day per week for 4 months starting at 20 years of age.
¦ Set up the source to start at age 20 and end at 20.33 (i.e., 20+4*30/365), using
stepwise (Cell E34 of the Simulation Control tab). Use the mask "other, mask"!, 4, 1,
7, 2, 7". This allows the pill to be taken only on day 1 of each week.
Media Sources, Intakes, and Relative Bioavailabilities
9
>0
a
1 Masking Help 1
Reset
Done
Mask #
Source
Period (days)
First day
blocked
Last day
blocked
1
1
7
2
7
RBA
RBA. Source 1
Figure 16 - Screenshot with Masks for Adulterated Therapeutic Home Remedies
Scenario
AALM Example Scenarios
These scenarios were developed to give users some starting points in developing their own
media exposure scenarios.
Example 1: IEUBK Exposure Scenario
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AALM v3.0 Users Guide
Import: Leggettlnput_Ex1.txt
This scenario details how users may replicate an Integrated Exposure Uptake Biokinetic
(IEUBK) model v2.0 exposure scenario in the AALM. The scenario begins at birth and ends
after 7 years and includes exposure to every medium except "Other" in the AALM or "Alternate"
in the IEUBK. This scenario uses IEUBK v2.0 defaults to estimate blood lead levels in a female
child. The IEUBK is not sex specific. To best match the IEUBK, it is recommended the
simulations for a male and female be averaged.
After importing the file, users can see and adjust imported values from the "Simulation Control"
tab by going down the screen to "Item 3". Set Active Media" and pressing the
button. The soil and dust intake rows are 45 and 55%, respectively, of the IEUBK defaults for
soil plus dust ingestion at each year of life. The scenario setup in this example is for an
exposure to 200 mg/kg of lead in soil. Press to exit the "Media" tab. From the
"Simulation Control" tab, press . When viewing results, users may wish to
zoom in on age ranges. To the side of each graph, the min and max value for an axis may be
entered. To return to Excel defaults, a non-numeric value may be entered. Also, users should
notice that some statistics are provided to the right of each graph. The age ranges can be
adjusted by users. The top graph is for blood lead, the average blood lead from the age of 1
year until the child turns 6 years is 2.436 |jg/dL with a 6.3% probability of exceeding 5.0 |jg/dL.
By comparison, the IEUBK model predicts an average blood lead from the age of 1 year until
the child turns 6 years is 2.31 |jg/dL with a <5.0% probability of exceeding 5.0 |jg/dL.
At the top of the screen, press to return to the "Simulation Control" tab. Sex is changed
in Cell E14 of the Simulation Control tab. Change the sex from female to male and press . The average blood lead
from the age of 1 year until the child turns 6 years is 2.327 |jg/dL with a 5.2% probability of
exceeding 5.0 |jg/dL. Thus, the average (male and female) blood lead is 2.38 |jg/dL with a 5.7%
probability of exceeding 5.0 |jg/dL.
If users opt to run a different soil lead concentration, then for consistency with the IEUBK model,
the dust concentration should equal 0.7*(soil lead concentration^ 100*(air lead concentration).
That is, an equation can be entered into Cell F39 as =0.7*F12+100*F93. Press the
button to return to the "Simulation Control" tab. If is selected, users can see
parameters imported to mimic the IEUBK model's respiratory compartment.
Example 1a: IEUBK Exposure Scenario
Import: Leggettlnput_Ex1a.txt
Rather than averaging the results for males and females as done in Example 1, this example
uses a modified growth curve and hematocrit level to approximate the average of males and
females in a single simulation. This approximation is valid for the average blood lead level over
the age of 1 to 6 years (i.e., 12 to 72 months in the IEUBK model version 2.0), the age range
recommended for assessment of residential sites when using the IEUBK model. The
approximation overestimates the average of male and female blood lead levels for 1-2 year-
olds by -1% and underestimates the blood leads of 5-6 year olds by -1%. Thus, the
approximation is best for the average over the full age range from 1 to 6 years and not any
individual year of life. The approximation yields a predicted blood lead that is within ±0.01 |jg/dL
55
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AALM v3.0 Users Guide
of the average for males and females for soil lead concentrations between 0 and 700 |jg/g with
other media (air, diet, and water) remaining at IEUBK v2.0 defaults.
Example 2: Background BLL
Import: Leggettlnput_Ex2.txt
This scenario models background blood lead levels. The objective of this scenario was to have
a blood lead of 0.6 |jg/dl_ in a female at age 30 using the "Other" pathway. The "Other" pathway
can be used to match blood lead levels to NHANES at a particular age. For this example,
intakes by the "Other" pathway replace the pathways of soil, indoor dust, water, air, and food.
Using the "Other" pathway provides a simple alternative to entering intake rates and
concentrations for all media pathways as a function of age to achieve a desired blood lead level.
Press the button. The "Media" tab will only show a single intake source from the
"Other" source. Since a constant intake is used for all ages in this scenario, it is only necessary
to enter this value at the age of zero. Press the button to return to the "Simulation
Control" tab and the press the button. After a few seconds, when the run
completes, users will be on the "Output Summary" tab. Press the button to
access the data results. When viewing results, users may wish to zoom in on age ranges. To
the side of each graph, the min and max value for an axis may be entered. To return to Excel
defaults, a non-numeric value may be entered. Also, users should notice that some statistics are
provided to the right of each graph. The age ranges can be adjusted by users.
This simulation was for a female and it took 5.59 jjg/day (with an assumed relative bioavailability
of 100%, RBA = 1) to achieve a blood lead concentration of 0.60 |jg/dl_ at 30 years of age.
When done viewing the data, press the button to return to the "Simulation Control" tab.
What would it take to reach this same level in a male? Change the sex from Female to Male in
Cell E14 and rerun the simulation. The male is found to only reach a blood lead concentration of
0.462 |jg/dl_ at 30 years of age. The difference in the blood concentrations is due largely to the
difference in compartmental volumes (in this case blood volume) between males and females.
The required intake for a male may be quickly estimated as 5.59 jjg/day x (0.600 / 0.462) = 7.26
|jg/day. This may be check by adjusting the intake in the "Other" media from 5.59 to 7.62 jjg/day
and rerunning the simulation.
Example 2a: Background BLL
Import: Leggettlnput_Ex2a.txt
Users may notice for Example 2 that using a constant rate of intake from birth to 30 years of age
results in rather high blood leads during the first 10 years of life. The file Leggettlnput_Ex2a.txt
achieves a blood lead of 0.60 |jg/dl_ at 30 years of age while maintaining an average blood lead
level of 0.60 |jg/dl_ from 1 to 50 years. After loading Leggettlnput_Ex2a.txt, notice that cell E34
on the "Simulation Control" tab has changed from Stepwise to Interpolated. Run the simulation
and view results to see that the blood lead is relatively constant across all ages. After returning
to the "Simulation Control" tab, users my select to view the intake array that
produced the rather constant blood leads. If the Leggettlnput_Ex2.txt is reload, in the "Media"
tab, notice that the number of ages in Cell D141 says 1, but more than one age is displayed.
This may be corrected by entering 20 into Cell D141 and subsequently entering 1 into Cell
D141.
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AALM v3.0 Users Guide
Example 3: Background BLL and Short-term Soil Exposure
Import: Leggettlnput_Ex3.txt
This scenario builds on Example 2, with an additional short-term, intermittent soil exposure of 5
days per week to 1000 |jg-Pb/g-soil (also, mg/kg or ppm) for 3 months beginning at age 30.
After importing the file, press the button. Then, notice how the soil exposure is
set up and making any desired changes to the scenario. Subsequently, press to return
to the "Simulation Control" tab and press the button. After a few seconds,
when the run completes, users will be on the "Output Summary" tab. Press the
button to access the data results. When viewing results, users may wish to zoom in on the age
range when the intermittent exposure to soil occurred. This may be accomplished by entering
30 in Cell E32 and 30.5 in Cell J32. The y-axis can also be zoomed into by changing Cells C16
and C27 to 0.5 and 1, respectively. After zooming in on the intermittent exposure period, the
weekly changes in the estimated blood lead levels are apparent.
Users should notice that some statistics are provided to the right of each graph. The age ranges
can be adjusted by users. During this intermittent exposure, the blood lead rises from 0.60
|jg/dL at 30 years and is 0.93 |jg/dl_ at 30.25 years. At 30.5 years, the blood lead has decrease
back to 0.63 |jg/dL.
Example 3b: Background BLL and Short-term Soil Exposure
Import: Leggettlnput_Ex3b.txt
This scenario builds on Example 2a, with an additional short-term, intermittent soil exposure of 5
days per week to 1000 |jg-Pb/g-soil (also, mg/kg or ppm) for 3 months beginning at age 30.
After loading Leggettlmput_Ex3a.txt, E34 on the "Simulation Control" tab has changed from
Stepwise to Interpolated. This requires that soil exposure be zero until 1 day before 30 years,
with an increase at 30 years to 1000 mg/kg. Similarly, the soil exposure goes back to zero at 1
day after 30.25 years.
After running the simulation, on the "Explore Data" tab the results appear nearly identical to
Example 2a. The blood lead rises from 0.60 |jg/dl_ at 30 years and is 0.93 |jg/dl_ at 30.25 years.
At 30.5 years, the blood lead has decrease back to 0.63 |jg/dL. Thus, the increased complexity
of keeping the blood lead at approximately 0.60 |jg/dl_ using the "Other" media did not change
the results of this adult exposure scenario.
Example 4: Occupational Air Exposure
Import: Leggettlnput_Ex4.txt
This scenario models only exposures from air but could also accommodate background blood
lead levels using the "Other" media as illustrated in Example 2 and 2a. The objective of this
scenario was to model the effect of an occupational air lead exposure on blood lead of a male
from birth to 60 years of age. The occupational exposure is assumed to occur for 20 years
beginning at the age of 20 years.
After importing the file, users can see and adjust imported values from the "Simulation Control"
tab by going down the screen to item "3. Set Active Media" and pressing the
button. The aerosol concentration at the workplace was 50 |jg-Pb/m3 with a daily intake of 3.09
m3/day. This ventilation rate is from an hourly rate of 0.54 m3/hour times an 8-hour daily
57
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AALM v3.0 Users Guide
exposure period times a time-weighting factor of 5/7 for a five day per week exposure. Press the
button to return to the "Simulation Control" tab.
Next, press the button [if this button is not visible, turn the air pathway off and
back on to view the deposition fractions and transfer rates for this simulation]. As described in
Section 2.3.3.1 of the Technical Support Document for the AALM v3.0, parameters for lung
deposition, absorption, and elimination kinetics are based largely on a study of human subjects
inhaling clean (not excessively carbonaceous due to a fuel rich mixture) automotive exhaust
from combustion of fuel containing 203Pb-labeled tetraethyllead. The aerosol particles were
reported to be 0.1 |jm and below. As such, the lung kinetics (used in AALM v2.0 and v3.0) are
most appropriate for near-ultrafine (around 0.1 |jm in diameter) combustion aerosols prior to the
phase-out of leaded gasoline, in part, because the size of airborne Pb has shifted from <2.5 |jm
prior to the phase-out of leaded gasoline to somewhere between 2.5 |jm and 10 |jm after the
phase-out. It is anticipated that a future version of the AALM will offer lung kinetics based on the
form and size of inhaled Pb particulates.
Press to return to the "Simulation Control" tab, then press the button.
When the run completes, users will be on the "Output Summary" tab. Press the
button to access the data results. Adjusting the statistics to the right of the blood lead versus
time plot to start at 20 and end at 40 years of age, the average blood lead is observed to be
26.1 |jg/dL with a maximum of 28.8 |jg/dL, which occurs at 40 years of age.
Example 5: Occupational Air Exposure
Import: Leggettlnput_Ex5.txt
This scenario is nearly identical to Example 4, except that the 20-year occupational exposure
occurs 5 days per week and not occur 2 days per week.
After importing the file, users can see and adjust imported values from the Simulation Control
tab by going down the screen to item "3. Set Active Media". Compared to Example 4, for Air, the
number of sources is now 2 (rather than 1) and the number of "Time Masks" is 1 (rather than 0).
Press the button.
In Example 4, the aerosol concentration was 50 |jg-Pb/m3 with a daily intake of 3.09 m3/day.
That ventilation rate is from an hourly rate of 0.54 m3/hour times an 8-hour daily exposure period
times a time-weighting factor of 5/7 for a five day per week exposure. As in Example 4, the
aerosol concentration is 50 |jg-Pb/m3, but it is listed now as a second exposure source. The
daily intake is now 4.32 m3/day rather than 3.09 m3/day in Example 2 because it is not
necessarily to time-weight the intake. In this case, the time-weighting of the intake is
accomplished by applying a "Time Mask" that zeros out the exposure by Source 2 on days 6
and 7 of the week. Press the button to return to the "Simulation Control" tab.
If is selected, the deposition fractions and transfer rates for this simulation may be
seen. If Source 2 does not appear, press to return to the "Simulation Control" tab, then
chance the number of sources from 2 to 0 and back to 2, then select the button.
The parameters for Source 1 and Source 2 can differ, but for this example are the same
because the exposure outside of the occupational period is minimal. As described in Example 4,
the lung kinetics (used in AALM v2.0 and v3.0) are most appropriate for near-ultrafine (around
0.1 |jm in diameter) combustion aerosols prior to the phase-out of leaded gasoline.
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AALM v3.0 Users Guide
After importing the file and making any desired changes to the scenario, press the button. After a few seconds, when the run completes, users will be on the "Output
Summary" tab. Press the button to access the data results.
Adjusting the statistics to the right of the blood lead versus time plot to start at 20 and end at 40
years of age, the average blood lead is observed to be 26.1 |jg/dl_ with a maximum of 29.3
|jg/dL, which occurs at 40 years of age. The maximum was 28.8 |jg/dl_ in Example 4. This
difference is due to a 5-day work week that results in slightly greater daily intakes and uptakes
of lead. The average blood lead and the average area under the curve are nearly identical.
Thus, other than the visualization of the weekly pattern, there is little benefit from the added
complexity of this scenario versus that in Example 4. However, the differences in maximal blood
leads would be larger in magnitude for scenarios where vacation periods caused a more
intermittent exposure pattern.
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Agency
PRESORTED STANDARD
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