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SupplementalInformation on E‐FAST CEM Outputs:

Degreaser Use

FIRST IS A DESCRIPTION OF THE ASSUMPTIONS, THEN THE MODEL OUTPUT FOLLOWS

(NOTE THAT FULL CITATIONS FOR ALL REFERENCES CITED CAN BE FOUND IN THE REFERENCE

SECTION OF THE RISK ASSESSMENT)

Exposure Scenario for Aerosol Solvent Degreaser

1. Description of the product from manufacturer’s product technical data sheet and

13‐Sep‐2011 Material Safety Data Sheet (see supplemental document titled “Supplemental

Product Information for the TSCA Workplan Chemical Risk Assessment of TCE (External

Review Draft).pdf” for more details):

• Removes oil and grease stains, ink, and fresh paint easily.

• Very effective for cleaning oily and greasy parts while servicing, repairing, or

replacing them.

• Can be used on metal parts prior to painting or soldering.

• Will not short motors, generators, compressors, condensers, or other electrical

equipment.

• Removes unwanted ink spots, dirt, grease, oil, fresh paint, and other troublesome

stains fast. Also effective on tar, adhesive marks, crayon marks, and lipstick.

• Use this product on metal parts prior to painting or soldering, painted surfaces,

insulation, rubber, and fabrics. Electric motors and generators may be cleaned   

while in use under properly ventilated conditions. Also for use on sewing

machines, cutting tools, switches, control panels, and thermostats.

2.    Assumptions for E‐FAST/CEM model runs:

• Start with the E‐FAST/CEM default assumptions for Aerosol Paint, and adjust the

assumptions for frequency of use, exposure duration (chronic), mass of product per

event, and duration of event to represent automotive hobbyist use of aerosol solvent

degreaser. Retain other assumptions for “Product Sprayed on Surface – Constant Rate

and Incremental Models”: assume that one percent of the sprayed product is

aerosolized and is therefore immediately available for uptake by inhalation; assume

that the remainder of the product contacts the targetsurface, and subsequently

volatilizes at a rate that depends upon the chemical’s molecular weight and vapor

pressure. [The aerosolized portion is treated using a constant emission rate model.

The remaining (non‐aerosolized) mass is treated by combining a constant application

rate with an exponentially declining rate for each instantaneously applied segment.]

• User is an automotive hobbyist who uses the aerosol solvent degreaser indoors, at

home, twice a month (24 events per year) to clean automotive parts. The scenario

does not include uses in the garage, on the driveway, etc.

• Hobbyist uses one can of aerosol solvent degreaser every year. Hobbyist therefore

uses 20 ounces of aerosol solvent degreaser per year, 20/24 = 0.83 ounces of aerosol

solvent degreaser per use, 0.83 ounces x 28.349523 g/ounce = 24 g aerosol solvent

degreaser/use.

• An actual formulation of aerosol solvent degreaser contains >90 percent TCE.  For
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E‐FAST/CEM, assume a weight fraction of 0.9.

• The hobbyist is an adult who uses the aerosol solvent degreaser for 57 years as an adult

(ages 21 to 78) or the hobbyist is a teenager or young adult who uses the aerosol solvent

degreaser for 5 years (ages 16 to 20).  Note that the model used these exposure duration

assumptions to develop chronic exposure estimates to TCE.  However, the OPPT TCE risk

assessment only evaluated acute exposures to TCE from the degreaser use and did not

use the chronic exposure estimates reported in this supplement.   

These products were assumed to be used twice per month.  With this type of exposure

frequency, EPA/OPPT assumed no substantial buildup of TCE in the body between

exposure events due to TCE’s short biological half‐life.  See section 2.6.1.4 for information

supporting this assumption.

• Non‐user (bystanders) residents of the home can be of any age.

• The E‐FAST/CEM runs estimate the active exposure of the user (hobbyist) and the passive

exposure of non‐users (bystanders) living in a home where the aerosol solvent degreaser is

used.   

Age groups for the user: ages 16 to 20; and ages 21 to 78 yrs.  

Age groups for the bystander: less than age 1; ages 1 to 2; ages 3 to 5; ages 6 to 10; ages 11

to 15; ages 16 to 20; and ages 21 to 78 yrs.

As discussed in section 2.5.3 and 2.5.3 of the risk assessment, age group‐specific simulations

showed that all of the age groups within each user and bystander category had the same

indoor air concentrations of TCE (expressed in ppm).   

The age groups for users did not include individuals <16 yrs based on the assumption that

adults would be the primary users of these products.  However, EPA/OPPT cannot rule out

that these products are used by teenagers and children.  Since there are not survey data for

consumer behavior patterns or a way to create varying behavior patterns for different age

groups, the indoor air concentrations shown in Table 2‐17 of the risk assessment were

extended to all potential users in this risk assessment.

• E‐FAST/CEM scenarios for children do not permit them to be present in the room of use

during product use. Estimated exposures therefore represent their passive exposures while

they are elsewhere in the home.

 Duration of event is 1 hour.

• Molecular weight of TCE is 131.39.

• Vapor pressure of TCE is 73.46 torr at 25 °C.

• Exposure factors for age bins, inhalation rates, body weights, and life expectancy were

derived from the 2011 Exposure Factors Handbook (EPA, 2011a) and replace the E‐FAST

defaults derived from the 1997 Exposure Factors Handbook (EPA,

1997).

 The interzonal airflow for the room of use (utility room) is 0.22/hour.  Each room in the

house has a different interzonal air flow if it is used as zone 1.  This flow is responsible for

moving the chemical from zone 1 (the room of use) to zone 2 (the rest of the house). This is

not the same as the air exchange rate which exchanges external air with air in the house. A

higher value for this parameter would cause the chemical studied to move more rapidly to

the rest of the house.  Areas like the kitchen or living room are found to have higher

interzonal air flows than rooms where the doors are commonly smaller or kept shut (e.g. the

bedroom).
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 For further information on the E‐FAST/CEM defaults or underlying equations, see the E‐FAST

documentation manual (EPA, 2007b).

3. Guide to the CEM inputs and outputs

 The E‐FAST/CEM exposure estimates are potential acute dose rates (ADR) that do not

include any assumptions about absorption through the lung.

 Although chronic information has been entered into some of the fields (freq of use) and

chronic output data (LADD) were reported, only the acute exposure data is used in the

risk assessment. This involved one use of the product in the morning of the day of use.

 The Zone 1 volume is 20 m3 and this is the volume of room 5 (the utility room). The

information about the user and the non‐user (bystander) is present in the activity

pattern data.  The user spends two hours in room 5 and 18 hours in the rest of the house

which is Zone 2. The volume of Zone 2 is the volume of the house minus the volume of

Zone 1 (the utility room) or 369 m3 – 20 m3 =40 m3

.

 In the different runs the body weight and inhalation rates are varied to reflect different

age groups. However, in the assessment only the back‐calculated 24 hour air

concentrations are used.

 Along with the acute and chronic doses, the peak concentration calculated for a 10 s

interval over the course of the simulation run was also displayed. This value was the

same for each of the user (67 mg/m3

) and non‐user (bystander; 6.2 mg/m3) runs. It

indicated the highest concentration encountered for 10 s by the simulated person over

the entire time period of the simulation. The peak concentration value was not used in

the risk assessment.

The peak concentration was independent of body weight and inhalation rate, as the air

concentrations in the simulation were only dependent on the consumer product and

house inputs.  This value was only valid for the 10 s interval and is not an indicator of the

exposure over longer time periods.  Commonly, this peak value occurs rapidly after the

product use is initiated and the indoor concentration decays as the room and house air

are exchanged with outdoor air free of the chemical of interest.
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E‐FAST/CEM Input and Output Summaries

for Aerosol Solvent Degreaser

CEM Inputs ID Number: 1 degreaser user 21‐78

Product: aerosol solvent degreaser Chemical Name: TCE

Scenario: User Defined Population: ages 21‐78

Molecular Weight (g/mole): 131.4 Vapor Pressure (torr): 73.46

Consumer Product Weight Fraction ‐ 

Central Tendency (unitless):

0.9 Consumer Product Weight Fraction

‐ High‐End (unitless):

0.9

Inhalation Inputs

Frequency of Use (chronic)

(events/yr):

24 Exposure Duration (chronic)

(years):

57

Frequency of Use (acute)

(events/day):

1 Exposure Duration (acute) (days): 1

Mass of Product Used per Event ‐ 

Central Tendency (g):

24 Mass of Product Used per Event ‐ 

High‐End (g):

24

Inhalation Rate During Use (m3/hr): 0.74 Duration of Event ‐ Central

Tendency (hours/event):

1

Inhalation Rate After Use (m3/hr): 0.611 Duration of Event ‐ High‐End

(hours/event):

1

Zone 1 Volume (m3): 20 Whole House Volume (m3): 369

Air Exchange Rate (air

exchanges/hr):

0.45 Body Weight (kg): 80

Portion of Aerosol in Air (unitless): 0.01    

Activity Patterns

User: 1 1 1 1 1 1 1 2 3 5 5 4 2 4 7 7 4 2 2 7 4 4 4 1

Non‐User:    1 1 1 1 1 1 1 1 3 2 4 4 2 4 7 7 4 2 2 7 4 4 4 1

Hour: 0 6 12 18

Start Time: 9 Room of Use: 5. Utility Room

Dermal Inputs

There are no Dermal inputs for this scenario.

Averaging Time (chronic) (days): 2.85e+

04

Averaging time (acute) (days) : 1

Activity Patterns: 1 Bedroom; 2 Kitchen; 3 Bathroom; 4 Living Room; 5 Utility Room; 6 Car; 7 Out (outside the

house)
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Exposure Units Result AT (days)

Chronic Cancer

LADDpot (mg/kg‐day) 1.37e‐01 2.85e+04 3 LADCpot (mg/m ) 6.66e‐01 2.85e+04

Acute

ADRpot (mg/kg‐day) 2.85e+00 1 3 Cppot (mg/m ) 2.59e+02 NA

CEM Inhalation Exposure Estimates

ID Number: 1 degreaser user 21‐78

Scenario: User Defined Population: ages 21‐78

Exposure Duration (years) chronic: 57 Exposure Duration (days) acute: 1

LADD ‐ Lifetime Average Daily Dose (mg/kg‐

day)

LADC ‐ Lifetime Average Daily Concentration

(mg/m3

)

ADR ‐ Acute Dose Rate (mg/kg‐day) Cp ‐ Peak Concentration (mg/m3)

Notes:  

• 78 years = 2.85e+04 days; pot ‐ potential dose

• The potential peak concentration (Cppot) is defined as the highest instantaneous air concentration that is

calculated by the model during any 10‐second time step, and should not be interpreted as a daily

maximum concentration.

• The general Agency guidance for assessing short‐term, infrequent events(for most chemicals, an exposure

of less than 24 hoursthat occurs no more frequently than monthly) is to treat such events as independent,

acute exposuresrather than as chronic exposure (EPA, 1998c).
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CEM Inputs ID Number: 2 degreaser non‐user 21‐78

Product: aerosol solvent degreaser Chemical Name: TCE

Scenario: User Defined Population: ages 21‐78

Molecular Weight (g/mole): 131.4 Vapor Pressure (torr): 73.46

Consumer Product Weight Fraction

‐ Central Tendency (unitless):

0.9 Consumer Product Weight Fraction

‐ High‐End (unitless):

0.9

Inhalation Inputs

Frequency of Use (chronic)

(events/yr):

24 Exposure Duration (chronic)

(years):

57

Frequency of Use (acute)

(events/day):

1 Exposure Duration (acute) (days): 1

Mass of Product Used per Event ‐ 

Central Tendency (g):

24 Mass of Product Used per Event ‐ 

High‐End (g):

24

Inhalation Rate During Use (m3/hr): 0.611 Duration of Event ‐ Central

Tendency (hours/event):

1

Inhalation Rate After Use (m3/hr): 0.611 Duration of Event ‐ High‐End

(hours/event):

1

Zone 1 Volume (m3): 20 Whole House Volume (m3): 369

Air Exchange Rate (air

exchanges/hr):

0.45 Body Weight (kg): 80

Portion of Aerosol in Air (unitless): 0.01

Activity Patterns

User: 1 1 1 1 1 1 1 1 3 2 4 4 2 4 7 7 4 2 2 7 4 4 4 1

Non‐User:    1 1 1 1 1 1 1 1 3 2 4 4 2 4 7 7 4 2 2 7 4 4 4 1

Hour: 0 6 12 18

Start Time: 9 Room of Use: 5. Utility Room

Dermal Inputs

There are no Dermal inputs for this scenario.

Averaging Time (chronic) (days): 2.85e+

04

Averaging time (acute) (days) : 1

Activity Patterns: 1 Bedroom; 2 Kitchen; 3 Bathroom; 4 Living Room; 5 Utility Room; 6 Car; 7 Out (outside the

house)
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Exposure Units Result AT (days)

Chronic Cancer

LADDpot (mg/kg‐day) 3.92e‐02 2.85e+04 3 LADCpot (mg/m ) 2.13e‐01 2.85e+04

Acute

ADRpot (mg/kg‐day) 8.16e‐01 1 3 Cppot (mg/m ) 3.84e+01 NA

CEM Inhalation Exposure Estimates

ID Number: 2 degreaser non‐user 21‐78

Scenario: User Defined Population: ages 21‐78

Exposure Duration (years) chronic: 57 Exposure Duration (days) acute: 1

LADD ‐ Lifetime Average Daily Dose (mg/kg‐day) LADC ‐ Lifetime Average Daily Concentration

(mg/m3

)

ADR ‐ Acute Dose Rate (mg/kg‐day) Cp ‐ Peak Concentration (mg/m3)

Notes:  

• 78 years = 2.85e+04 days; pot ‐ potential dose

• The potential peak concentration (Cppot) is defined as the highest instantaneous air concentration that is

calculated by the model during any 10‐second time step, and should not be interpreted as a daily

maximum concentration.

• The general Agency guidance for assessing short‐term, infrequent events(for most chemicals, an exposure

of less than 24 hoursthat occurs no more frequently than monthly) is to treat such events as independent,

acute exposuresrather than as chronic exposure (EPA, 1998c).
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CEM Inputs ID Number: 3 degreaser user 16‐20

Product: aerosol solvent degreaser Chemical Name: TCE

Scenario: User Defined Population: ages 16‐20

Molecular Weight (g/mole): 131.4 Vapor Pressure (torr): 73.46

Consumer Product Weight Fraction

‐ Central Tendency (unitless):

0.9 Consumer Product Weight Fraction

‐ High‐End (unitless):

0.9

Inhalation Inputs

Frequency of Use (chronic)

(events/yr):

24 Exposure Duration (chronic)

(years):

5

Frequency of Use (acute)

(events/day):

1 Exposure Duration (acute) (days): 1

Mass of Product Used per Event ‐ 

Central Tendency (g):

24 Mass of Product Used per Event ‐ 

High‐End (g):

24

Inhalation Rate During Use (m3/hr): 0.72 Duration of Event ‐ Central

Tendency (hours/event):

1

Inhalation Rate After Use (m3/hr): 0.679 Duration of Event ‐ High‐End

(hours/event):

1

Zone 1 Volume (m3): 20 Whole House Volume (m3): 369

Air Exchange Rate (air

exchanges/hr):

0.45 Body Weight (kg): 71.6

Portion of Aerosol in Air (unitless): 0.01

Activity Patterns

User: 1 1 1 1 1 1 1 1 3 5 4 4 2 4 7 7 4 2 2 7 4 4 4 1

Non‐User:    1 1 1 1 1 1 1 1 3 2 4 4 2 4 7 7 4 2 2 7 4 4 4 1

Hour: 0 6 12 18

Start Time: 9 Room of Use: 5. Utility Room

Dermal Inputs

There are no Dermal inputs for this scenario.

Averaging Time (chronic) (days): 2.85e+

04

Averaging time (acute) (days) : 1

Activity Patterns: 1 Bedroom; 2 Kitchen; 3 Bathroom; 4 Living Room; 5 Utility Room; 6 Car; 7 Out (outside the

house)
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Exposure Units Result AT (days)

Chronic Cancer

LADDpot (mg/kg‐day) 1.18e‐02 2.85e+04 3 LADCpot (mg/m ) 5.00e‐02 2.85e+04

Acute

ADRpot (mg/kg‐day) 2.81e+00 1 3 Cppot (mg/m ) 2.59e+02 NA

CEM Inhalation Exposure Estimates

ID Number: 3 degreaser user 16‐20

Scenario: User Defined Population: ages 16‐20

Exposure Duration (years) chronic: 5 Exposure Duration (days) acute: 1

LADD ‐ Lifetime Average Daily Dose (mg/kg‐day) LADC ‐ Lifetime Average Daily Concentration

(mg/m3

)

ADR ‐ Acute Dose Rate (mg/kg‐day) Cp ‐ Peak Concentration (mg/m3)

Notes:  

• 78 years = 2.85e+04 days; pot ‐ potential dose

• The potential peak concentration (Cppot) is defined as the highest instantaneous air concentration that is

calculated by the model during any 10‐second time step, and should not be interpreted as a daily

maximum concentration.

• The general Agency guidance for assessing short‐term, infrequent events(for most chemicals, an exposure

of less than 24 hoursthat occurs no more frequently than monthly) is to treat such events as independent,

acute exposuresrather than as chronic exposure (EPA, 1998c).
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CEM Inputs ID Number: 4 degreaser non‐user 16‐20

Product: aerosol solvent degreaser Chemical Name: TCE

Scenario: User Defined Population: ages 16‐20

Molecular Weight (g/mole): 131.4 Vapor Pressure (torr): 73.46

Consumer Product Weight Fraction

‐ Central Tendency (unitless):

0.9 Consumer Product Weight Fraction

‐ High‐End (unitless):

0.9

Inhalation Inputs

Frequency of Use (chronic)

(events/yr):

24 Exposure Duration (chronic)

(years):

5

Frequency of Use (acute)

(events/day):

1 Exposure Duration (acute) (days): 1

Mass of Product Used per Event ‐ 

Central Tendency (g):

24 Mass of Product Used per Event ‐ 

High‐End (g):

24

Inhalation Rate During Use (m3/hr): 0.679 Duration of Event ‐ Central

Tendency (hours/event):

1

Inhalation Rate After Use (m3/hr): 0.679 Duration of Event ‐ High‐End

(hours/event):

1

Zone 1 Volume (m3): 20 Whole House Volume (m3): 369

Air Exchange Rate (air

exchanges/hr):

0.45 Body Weight (kg): 71.6

Portion of Aerosol in Air (unitless): 0.01

Activity Patterns

User: 1 1 1 1 1 1 1 1 3 2 4 4 2 4 7 7 4 2 2 7 4 4 4 1

Non‐User:    1 1 1 1 1 1 1 1 3 2 4 4 2 4 7 7 4 2 2 7 4 4 4 1

Hour: 0 6 12 18

Start Time: 9 Room of Use: 5. Utility Room

Dermal Inputs

There are no Dermal inputs for this scenario.

Averaging Time (chronic) (days): 2.85e+

04

Averaging time (acute) (days) : 1

Activity Patterns: 1 Bedroom; 2 Kitchen; 3 Bathroom; 4 Living Room; 5 Utility Room; 6 Car; 7 Out (outside the

house)
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Exposure Units Result AT (days)

Chronic Cancer

LADDpot (mg/kg‐day) 4.27e‐03 2.85e+04 3 LADCpot (mg/m ) 1.87e‐02 2.85e+04

Acute

ADRpot (mg/kg‐day) 1.01e+00 1 3 Cppot (mg/m ) 3.84e+01 NA

CEM Inhalation Exposure Estimates

ID Number: 4 degreaser non‐user 16‐20

Scenario: User Defined Population: ages 16‐20

Exposure Duration (years) chronic: 5 Exposure Duration (days) acute: 1

LADD ‐ Lifetime Average Daily Dose (mg/kg‐day) LADC ‐ Lifetime Average Daily Concentration

(mg/m3

)

ADR ‐ Acute Dose Rate (mg/kg‐day) Cp ‐ Peak Concentration (mg/m3)

Notes:  

• 78 years = 2.85e+04 days; pot ‐ potential dose

• The potential peak concentration (Cppot) is defined as the highest instantaneous air concentration that is

calculated by the model during any 10‐second time step, and should not be interpreted as a daily

maximum concentration.

• The general Agency guidance for assessing short‐term, infrequent events(for most chemicals, an exposure

of less than 24 hoursthat occurs no more frequently than monthly) is to treat such events as independent,

acute exposuresrather than as chronic exposure (EPA, 1998c).
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CEM Inputs ID Number: 5 degreaser non‐user 11‐15

Product: aerosol solvent degreaser Chemical Name: TCE

Scenario: User Defined Population: ages 11‐15

Molecular Weight (g/mole): 131.4 Vapor Pressure (torr): 73.46

Consumer Product Weight Fraction

‐ Central Tendency (unitless):

0.9 Consumer Product Weight Fraction

‐ High‐End (unitless):

0.9

Inhalation Inputs

Frequency of Use (chronic)

(events/yr):

24 Exposure Duration (chronic)

(years):

5

Frequency of Use (acute)

(events/day):

1 Exposure Duration (acute) (days): 1

Mass of Product Used per Event ‐ 

Central Tendency (g):

24 Mass of Product Used per Event ‐ 

High‐End (g):

24

Inhalation Rate During Use (m3/hr): 0.633 Duration of Event ‐ Central

Tendency (hours/event):

1

Inhalation Rate After Use (m3/hr): 0.633 Duration of Event ‐ High‐End

(hours/event):

1

Zone 1 Volume (m3): 20 Whole House Volume (m3): 369

Air Exchange Rate (air

exchanges/hr):

0.45 Body Weight (kg): 56.8

Portion of Aerosol in Air (unitless): 0.01

Activity Patterns

User: 1 1 1 1 1 1 1 1 3 2 4 4 2 4 7 7 4 2 2 7 4 4 4 1

Non‐User:    1 1 1 1 1 1 1 1 3 2 4 4 2 4 7 7 4 2 2 7 4 4 4 1

0 Hour: 0 6 12 18

Start Time: 9 Room of Use: 5. Utility Room

Dermal Inputs

There are no Dermal inputs for this scenario.

Averaging Time (chronic) (days): 2.85e+

04

Averaging time (acute) (days) : 1

Activity Patterns: 1 Bedroom; 2 Kitchen; 3 Bathroom; 4 Living Room; 5 Utility Room; 6 Car; 7 Out (outside the

house)
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Exposure Units Result AT (days)

Chronic Cancer

LADDpot (mg/kg‐day) 5.01e‐03 2.85e+04 3 LADCpot (mg/m ) 1.87e‐02 2.85e+04

Acute

ADRpot (mg/kg‐day) 1.19e+00 1 3 Cppot (mg/m ) 3.84e+01 NA

CEM Inhalation Exposure Estimates

ID Number: 5 degreaser non‐user 11‐15

Scenario: User Defined Population: ages 11‐15

Exposure Duration (years) chronic: 5 Exposure Duration (days) acute: 1

LADD ‐ Lifetime Average Daily Dose (mg/kg‐day) LADC ‐ Lifetime Average Daily Concentration

(mg/m3

)

ADR ‐ Acute Dose Rate (mg/kg‐day) Cp ‐ Peak Concentration (mg/m3)

Notes:  

• 78 years = 2.85e+04 days; pot ‐ potential dose

• The potential peak concentration (Cppot) is defined as the highest instantaneous air concentration that is

calculated by the model during any 10‐second time step, and should not be interpreted as a daily

maximum concentration.

• The general Agency guidance for assessing short‐term, infrequent events(for most chemicals, an exposure

of less than 24 hoursthat occurs no more frequently than monthly) is to treat such events as independent,

acute exposuresrather than as chronic exposure (EPA, 1998c).
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CEM Inputs ID Number: 6 degreaser non‐user 6‐10

Product: aerosol solvent degreaser Chemical Name: TCE

Scenario: User Defined Population: ages 6‐10

Molecular Weight (g/mole): 131.4 Vapor Pressure (torr): 73.46

Consumer Product Weight Fraction

‐ Central Tendency (unitless):

0.9 Consumer Product Weight Fraction

‐ High‐End (unitless):

0.9

Inhalation Inputs

Frequency of Use (chronic)

(events/yr):

24 Exposure Duration (chronic)

(years):

5

Frequency of Use (acute)

(events/day):

1 Exposure Duration (acute) (days): 1

Mass of Product Used per Event ‐ 

Central Tendency (g):

24 Mass of Product Used per Event ‐ 

High‐End (g):

24

Inhalation Rate During Use (m3/hr): 0.5 Duration of Event ‐ Central

Tendency (hours/event):

1

Inhalation Rate After Use (m3/hr): 0.5 Duration of Event ‐ High‐End

(hours/event):

1

Zone 1 Volume (m3): 20 Whole House Volume (m3): 369

Air Exchange Rate (air

exchanges/hr):

0.45 Body Weight (kg): 31.8

Portion of Aerosol in Air (unitless): 0.01

Activity Patterns

User: 1 1 1 1 1 1 1 1 3 2 4 4 2 4 7 7 4 2 2 7 4 4 4 1

Non‐User:    1 1 1 1 1 1 1 1 3 2 4 4 2 4 7 7 4 2 2 7 4 4 4 1

Hour: 0 6 12 18

Start Time: 9 Room of Use: 5. Utility Room

Dermal Inputs

There are no Dermal inputs for this scenario.

Averaging Time (chronic) (days): 2.85e+

04

Averaging time (acute) (days) : 1

Activity Patterns: 1 Bedroom; 2 Kitchen; 3 Bathroom; 4 Living Room; 5 Utility Room; 6 Car; 7 Out (outside the

house)
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Exposure Units Result AT (days)

Chronic Cancer

LADDpot (mg/kg‐day) 7.07e‐03 2.85e+04 3 LADCpot (mg/m ) 1.87e‐02 2.85e+04

Acute

ADRpot (mg/kg‐day) 1.68e+00 1 3 Cppot (mg/m ) 3.84e+01 NA

CEM Inhalation Exposure Estimates

ID Number: 6 degreaser non‐user 6‐10

Scenario: User Defined Population: ages 6‐10

Exposure Duration (years) chronic: 5 Exposure Duration (days) acute: 1

LADD ‐ Lifetime Average Daily Dose (mg/kg‐day) LADC ‐ Lifetime Average Daily Concentration

(mg/m3

)

ADR ‐ Acute Dose Rate (mg/kg‐day) Cp ‐ Peak Concentration (mg/m3)

Notes:  

• 78 years = 2.85e+04 days; pot ‐ potential dose

• The potential peak concentration (Cppot) is defined as the highest instantaneous air concentration that is

calculated by the model during any 10‐second time step, and should not be interpreted as a daily

maximum concentration.

• The general Agency guidance for assessing short‐term, infrequent events(for most chemicals, an exposure

of less than 24 hoursthat occurs no more frequently than monthly) is to treat such events as independent,

acute exposuresrather than as chronic exposure (EPA, 1998c).
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CEM Inputs ID Number: 7 degreaser non‐user 3‐5

Product: aerosol solvent degreaser Chemical Name: TCE

Scenario: User Defined Population: ages 3‐5

Molecular Weight (g/mole): 131.4 Vapor Pressure (torr): 73.46

Consumer Product Weight Fraction

‐ Central Tendency (unitless):

0.9 Consumer Product Weight Fraction

‐ High‐End (unitless):

0.9

Inhalation Inputs

Frequency of Use (chronic)

(events/yr):

24 Exposure Duration (chronic)

(years):

3

Frequency of Use (acute)

(events/day):

1 Exposure Duration (acute) (days): 1

Mass of Product Used per Event ‐ 

Central Tendency (g):

24 Mass of Product Used per Event ‐ 

High‐End (g):

24

Inhalation Rate During Use (m3/hr): 0.421 Duration of Event ‐ Central

Tendency (hours/event):

1

Inhalation Rate After Use (m3/hr): 0.421 Duration of Event ‐ High‐End

(hours/event):

1

Zone 1 Volume (m3): 20 Whole House Volume (m3): 369

Air Exchange Rate (air

exchanges/hr):

0.45 Body Weight (kg): 18.6

Portion of Aerosol in Air (unitless): 0.01

Activity Patterns

User: 1 1 1 1 1 1 1 1 3 2 4 4 2 4 7 7 4 2 2 7 4 4 4 1

Non‐User:    1 1 1 1 1 1 1 1 3 2 4 4 2 4 7 7 4 2 2 7 4 4 4 1

Hour: 0 6 12 18

Start Time: 9 Room of Use: 5. Utility Room

Dermal Inputs

There are no Dermal inputs for this scenario.

Averaging Time (chronic) (days): 2.85e+

04

Averaging time (acute) (days) : 1

Activity Patterns: 1 Bedroom; 2 Kitchen; 3 Bathroom; 4 Living Room; 5 Utility Room; 6 Car; 7 Out (outside the

house)
17

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Exposure Units Result AT (days)

Chronic Cancer

LADDpot (mg/kg‐day) 6.11e‐03 2.85e+04 3 LADCpot (mg/m ) 1.12e‐02 2.85e+04

Acute

ADRpot (mg/kg‐day) 2.42e+00 1 3 Cppot (mg/m ) 3.84e+01 NA

CEM Inhalation Exposure Estimates

ID Number: 7 degreaser non‐user 3‐5

Scenario: User Defined Population: ages 3‐5

Exposure Duration (years) chronic: 3 Exposure Duration (days) acute: 1

LADD ‐ Lifetime Average Daily Dose (mg/kg‐day) LADC ‐ Lifetime Average Daily Concentration

(mg/m3

)

ADR ‐ Acute Dose Rate (mg/kg‐day) Cp ‐ Peak Concentration (mg/m3)

Notes:  

• 78 years = 2.85e+04 days; pot ‐ potential dose

• The potential peak concentration (Cppot) is defined as the highest instantaneous air concentration that is

calculated by the model during any 10‐second time step, and should not be interpreted as a daily

maximum concentration.

• The general Agency guidance for assessing short‐term, infrequent events(for most chemicals, an exposure

of less than 24 hoursthat occurs no more frequently than monthly) is to treat such events as independent,

acute exposuresrather than as chronic exposure (EPA, 1998c).
18

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CEM Inputs ID Number: 8 degreaser non‐user 1‐2

Product: aerosol solvent degreaser Chemical Name: TCE

Scenario: User Defined Population: ages 1‐2

Molecular Weight (g/mole): 131.4 Vapor Pressure (torr): 73.46

Consumer Product Weight Fraction

‐ Central Tendency (unitless):

0.9 Consumer Product Weight Fraction

‐ High‐End (unitless):

0.9

Inhalation Inputs

Frequency of Use (chronic)

(events/yr):

24 Exposure Duration (chronic)

(years):

2

Frequency of Use (acute)

(events/day):

1 Exposure Duration (acute) (days): 1

Mass of Product Used per Event ‐ 

Central Tendency (g):

24 Mass of Product Used per Event ‐ 

High‐End (g):

24

Inhalation Rate During Use (m3/hr): 0.35 Duration of Event ‐ Central

Tendency (hours/event):

1

Inhalation Rate After Use (m3/hr): 0.35 Duration of Event ‐ High‐End

(hours/event):

1

Zone 1 Volume (m3): 20 Whole House Volume (m3): 369

Air Exchange Rate (air

exchanges/hr):

0.45 Body Weight (kg): 12.6

Portion of Aerosol in Air (unitless): 0.01

Activity Patterns

User: 1 1 1 1 1 1 1 1 3 2 4 4 2 4 7 7 4 2 2 7 4 4 4 1

Non‐User:    1 1 1 1 1 1 1 1 3 2 4 4 2 4 7 7 4 2 2 7 4 4 4 1

Hour: 0 6 12 18

Start Time: 9 Room of Use: 5. Utility Room

Dermal Inputs

There are no Dermal inputs for this scenario.

Averaging Time (chronic) (days): 2.85e+

04

Averaging time (acute) (days) : 1

Activity Patterns: 1 Bedroom; 2 Kitchen; 3 Bathroom; 4 Living Room; 5 Utility Room; 6 Car; 7 Out (outside the

house)
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Exposure Units Result AT (days)

Chronic Cancer

LADDpot (mg/kg‐day) 5.00e‐03 2.85e+04 3 LADCpot (mg/m ) 7.50e‐03 2.85e+04

Acute

ADRpot (mg/kg‐day) 2.97e+00 1 3 Cppot (mg/m ) 3.84e+01 NA

CEM Inhalation Exposure Estimates

ID Number: 8 degreaser non‐user 1‐2

Scenario: User Defined Population: ages 1‐2

Exposure Duration (years) chronic: 2 Exposure Duration (days) acute: 1

LADD ‐ Lifetime Average Daily Dose (mg/kg‐day) LADC ‐ Lifetime Average Daily Concentration

(mg/m3

)

ADR ‐ Acute Dose Rate (mg/kg‐day) Cp ‐ Peak Concentration (mg/m3)

Notes:  

• 78 years = 2.85e+04 days; pot ‐ potential dose

• The potential peak concentration (Cppot) is defined as the highest instantaneous air concentration that is

calculated by the model during any 10‐second time step, and should not be interpreted as a daily maximum

concentration.

• The general Agency guidance for assessing short‐term, infrequent events(for most chemicals, an exposure

of less than 24 hoursthat occurs no more frequently than monthly) is to treat such events as independent,

acute exposuresrather than as chronic exposure (EPA, 1998c).
20

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CEM Inputs ID Number: 9 degreaser non‐user <1

Product: aerosol solvent degreaser Chemical Name: TCE

Scenario: User Defined Population: age <1

Molecular Weight (g/mole): 131.4 Vapor Pressure (torr): 73.46

Consumer Product Weight Fraction

‐ Central Tendency (unitless):

0.9 Consumer Product Weight Fraction

‐ High‐End (unitless):

0.9

Inhalation Inputs

Frequency of Use (chronic)

(events/yr):

24 Exposure Duration (chronic)

(years):

1

Frequency of Use (acute)

(events/day):

1 Exposure Duration (acute) (days): 1

Mass of Product Used per Event ‐ 

Central Tendency (g):

24 Mass of Product Used per Event ‐ 

High‐End (g):

24

Inhalation Rate During Use (m3/hr): 0.23 Duration of Event ‐ Central

Tendency (hours/event):

1

Inhalation Rate After Use (m3/hr): 0.23 Duration of Event ‐ High‐End

(hours/event):

1

Zone 1 Volume (m3): 20 Whole House Volume (m3): 369

Air Exchange Rate (air

exchanges/hr):

0.45 Body Weight (kg): 7.8

Portion of Aerosol in Air (unitless): 0.01

Activity Patterns

User: 1 1 1 1 1 1 1 1 3 2 4 4 2 4 7 7 4 2 2 7 4 4 4 1

Non‐User:    1 1 1 1 1 1 1 1 3 2 4 4 2 4 7 7 4 2 2 7 4 4 4 1

Hour: 0 6 12 18

Start Time: 9 Room of Use: 5. Utility Room

Dermal Inputs

There are no Dermal inputs for this scenario.

Averaging Time (chronic) (days): 2.85e+

04

Averaging time (acute) (days) : 1

Activity Patterns: 1 Bedroom; 2 Kitchen; 3 Bathroom; 4 Living Room; 5 Utility Room; 6 Car; 7 Out (outside the

house)
21

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Exposure Units Result AT (days)

Chronic Cancer

LADDpot (mg/kg‐day) 2.65e‐03 2.85e+04

3 LADCpot (mg/m ) 3.75e‐03 2.85e+04

Acute

ADRpot (mg/kg‐day) 3.15e+0

0

1

3 Cppot (mg/m ) 3.84e+0

1

NA

CEM Inhalation Exposure Estimates

ID Number: 9 degreaser non‐user <1

Scenario: User Defined Population: age <1

Exposure Duration (years) chronic: 1 Exposure Duration (days) acute: 1

LADD ‐ Lifetime Average Daily Dose (mg/kg‐day) LADC ‐ Lifetime Average Daily Concentration

(mg/m3

)

ADR ‐ Acute Dose Rate (mg/kg‐day) Cp ‐ Peak Concentration (mg/m3)

Notes:  
22

Exposure Parameter Values Used in E‐FAST/CEM for TCE Modeling.

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Exposure

Parameter Population Exposure

Type

Default

Value Source Comment

Body

Weight

(BW)

Adult

(≥21 years)

All 80.0 kg EPA

(2011a)

Table 8‐3 (page 8‐12): Average of mean

body weights for all adults (≥21 years),

male and female combined.  Based on

U.S. EPA analysis of NHANES 1999‐2006

Youth

(16‐20

years)

All 71.6 kg EPA

(2011a)

Table 8‐1 (page 8‐2): Mean body weight

for age class 16‐<21 years. See Table 8‐3

(page 8‐12) for sample sizes.  Based on

U.S. EPA analysis of NHANES 1999‐2006

Youth

(11‐15

years)

All 56.8 kg EPA

(2011a)

Table 8‐1 (page 8‐2): Mean body weight

for age class 11‐<16 years. See Table 8‐3

(page 8‐12) for sample sizes.  Based on

U.S. EPA analysis of NHANES 1999‐2006

Child

(6‐10

years)

All 31.8 kg EPA

(2011a)

Table 8‐1 (page 8‐2): Mean body weight

for age class 6‐<11 years.  See Table 8‐3

(page 8‐12) for sample sizes.  Based on

U.S. EPA analysis of NHANES 1999‐2006

Small child

(3‐5 years)

All 18.6 kg EPA

(2011a)

Table 8‐1 (page 8‐2): Mean body weight

for age class 3‐<6 years. See Table 8‐3

(page 8‐12) for sample sizes.  Based on

U.S. EPA analysis of NHANES 1999‐2006

Infant

(1‐2 years)

All 12.6 kg EPA

(2011a)

Table 8‐1 (page 8‐2): Average of mean

body weights for age classes 1‐<2 and 2‐ 

<3 years. See Table 8‐3 (page 8‐12) for

sample sizes.  Based on U.S. EPA analysis

of NHANES 1999‐2006 data.

Infant

(<1 year)

All 7.8 kg EPA

(2011a)

Table 8‐1 (page 8‐2): Weighted average of

mean body weights for age classes 0‐<1, 1‐ 

<3, 3‐<6, and 6‐<12 months.  See Table 8‐3

(page 8‐12) for sample sizes.  Based on U.S.

EPA analysis of NHANES 1999‐2006 data.
23

Exposure Parameter Values Used in E‐FAST/CEM for TCE Modeling.

Version 06/18/2014

Exposure

Parameter Population Exposure

Type

Default

Value Source Comment

Inhalation

Rate

(InhR)

Adult

(≥21 years)

Chronic 14.7 m3

/day EPA

(2011a)

For general population exposures,

Table 6‐1 (page 6‐3): Average of

mean long‐term exposure values

for inhalation (males and females

combined) for age classes 21‐<31,

31‐<41, 41‐<51, 51‐<61, 61‐<71,

and 71‐<81years.

Adult

(≥21 years)

Acute 0.74

m3

/hour

EPA

(2011a)

For consumer exposures, Table 6‐2

(page 6‐4): Average of mean short‐ 

term exposure values for inhalation

during light activity (males and

females combined) for the age

classes 21‐<31, 31‐<41, 41‐<51, 51‐ 

<61, 61‐<71, and 71‐<81 years.  For

consumer scenarios: 0.74 m3/hour

during product use (based on short‐

term exposure at light activity level;

Table 6‐2, page 6‐4) and

0.611 m3

/hour after product use.

Youth

(16‐ 

20 years)

Acute 3 16.3 m /day EPA

(2011a)

For general population exposures,

Table 6‐1 (page 6‐3): Mean long‐ 

term exposure value for inhalation

(males and females combined) for

age class 16‐<21 years. Children are

typically considered to be non‐ 

users, however, for consumer

exposures: 0.72 m3

/hour during

product use (based on short‐term

exposure at light activity level;

Table 6‐2, page 6‐4) and 0.679

m3

/hour after product use.

Youth

(11‐ 

15 years)

Acute 15.2 m3

/day EPA

(2011a)

For general population exposures:

Table 6‐1 (page 6‐3): Mean long‐ 

term exposure value for inhalation

(males and females combined) for

age class 11‐<16 years. Children are

considered to be non‐users:

0.633 m3

/hour before and after

product use.
24

Exposure Parameter Values Used in E‐FAST/CEM for TCE Modeling.

Version 06/18/2014

Exposure

Parameter Population Exposure

Type

Default

Value Source Comment

Child

(6‐10

years)

Acute 12.0 m3

/day EPA

(2011a)

For general population exposures:

Table 6‐1 (page 6‐3): Mean long‐ 

term exposure value for inhalation

(males and females combined) for

age class 6‐<11 years.  Children are

considered to be non‐users:

0.500 m3

/hour before and after

product use.

Small child

(3‐5 years)

Acute 10.1 m3

/day EPA

(2011a)

For general population exposures:

Table 6‐1 (page 6‐3): Mean long‐ 

term exposure value for inhalation

(males and females combined) for

age class 3‐<6 years. Children are

considered to be non‐users:

0.421 m3

/hour before and after

product use.

Infant

(1‐2 years)

Acute 8.5 m3

/day EPA

(2011a)

For general population exposures:

Table 6‐1 (page 6‐3): Average of

mean long‐term exposure values

for inhalation (males and females

combined) for age classes 1‐<2 and

2‐<3 years.  Children are considered

to be non‐users: 0.35 m3

/hour

before and after product use.

Infant

(<1 year)

Acute 5.4 m3

/day EPA

(2011a)

For general population exposures:

Table 6‐1 (page 6‐3): Mean long‐ 

term exposure values for inhalation

(males and females combined) for

the age class birth to <1 year.

Children are considered to be non‐ 

users: 0.23 m3

/hour before and

after product use.

Exposure

Duration (ED)

Adult

(≥21 years)

Chronic 57 years EPA

(2011a)

Adult lifetime exposure duration,

based on life expectancy of 78 years

(Table 18‐1).  Exposure from 21 to

78 years of age. Previously,

18 years was used as the initiation

of this duration.  For consumer

exposures.

Adult

(≥21 years)

Acute 1 day _ Assumed 1‐day exposure for acute

scenarios.
25

Exposure Parameter Values Used in E‐FAST/CEM for TCE Modeling.

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Exposure

Parameter Population Exposure

Type

Default

Value Source Comment

Youth

(16‐ 

20 years)

Acute 1 day _ Assumed 1‐day exposure for acute

scenarios.

Youth

(11‐ 

15 years)

Acute 1 day _ Assumed 1‐day exposure for acute

scenarios.

Child

(6‐ 

10 years)

Acute 1 day _ Assumed 1‐day exposure for acute

scenarios.

Small child

(3‐5 years)

Acute 1 day _ Assumed 1‐day exposure for acute

scenarios.

Infant

(1‐2 years)

Acute 1 day _ Assumed 1‐day exposure for acute

scenarios.

Infant

(<1 year)

Acute 1 day _ Assumed 1‐day exposure for acute

scenarios.

Carcinogenic

Averaging

Time (AT)

Adult

(≥21 years)

Chronic 78 years EPA

(2011a)

Table 18‐1 (page 18‐1): Average of

male and female life expectancy.

This recommended value is

reflective of the average life

expectancy of the general

population. Data were collected in

2007 and published in 2010 (Xu et

al., 2010)

Acute

Averaging

Time (AT)

All Acute 1 day _ Assumed 1‐day exposure for acute

scenarios.