MEMORANDUM

TO: Bill Swietlik, EPA

FROM: Jill Lucy, ERG

DATE: September 21, 2015

SUBJECT: Fish Consumption Rates Used in the Environmental Assessment (EA) 

Human Health Module (DCN SE04482)

The U.S. Environmental Protection Agency (EPA) proposed revised effluent limitations 

guidelines and standards (ELGs) for the Steam Electric Power Generating Point Source Category 

(40 CFR Part 423) on June 7, 2013 (78 FR 34432). In support of the development of the revised 

ELGs, ERG supported EPA in conducting an environmental assessment (EA) to evaluate the 

potential environmental and human health impacts of pollutant loadings associated with current 

(i.e., baseline) discharges and assess the potential improvement from pollutant loading removals

under varying regulatory options.

ERG developed a national-scale immediate receiving water (IRW) model: human health 

module to estimate the daily contaminant doses for human receptors resulting from eating 

trophic level 3 (T3) and trophic level 4 (T4) fish caught in the immediate receiving waters from 

steam electric power plant discharges. This memorandum presents the following updates to the 

IRW Model: Human Health Module input data for the final rulemaking:

 Revised fish consumption rates based on consumer-only data, rather than per 

capita data, for finfish, where available.

 Added cohorts based on race population to support the environmental justice (EJ) 

analysis.

The memorandum includes the following sections:

 Section 1: Overview of Input Data in the Human Health Module.

 Section 2: Methodology to Select Fish Consumption Rates.

 Section 3: Fish Consumption Rates for Standard Cohorts.

 Section 4: Fish Consumption Rates for Cohorts in Environmental Justice 

Analyses.

 Section 5: References.
Memorandum

September 21, 2015

Page 2

1. OVERVIEW OF INPUT DATA IN THE HUMAN HEALTH MODULE

The IRW model: human health module evaluated the cancer risk and potential to cause 

non-cancer health effects from the consumption of fish within the following age and 

consumption categories (i.e., cohorts):

 Child recreational fishers.

 Child subsistence fishers.

 Adult recreational fishers.

 Adult subsistence fishers.

The model estimated the daily contaminant (i.e., pollutant)

1

doses for human receptors as 

a result of eating T3 and T4 contaminated fish. The model calculated the average concentration 

of pollutants in a fish filet consumed by humans based on a consumption diet of 36 percent T3 

and 64 percent T4 fish.

2 The IRW model: human health module then calculated the daily dose 

of pollutants from fish consumption for each cohort included in the analysis. The model 

calculated average daily doses (ADDs) and lifetime average daily doses (LADDs) to human 

receptors. The ADD (for noncarcinogenic substances) and LADD (carcinogenic substances) 

were specific for each pollutant and each immediate receiving water. Equations 1 and 2 show the 

calculation of ADD and LADD.

ADD =

Cfish_filet × CRfish × Ffish

1000 × BW

Equation 1

Where:

ADD = Average daily dose of pollutant from fish 

consumption (milligram [mg]/kilogram [kg] 

body weight [BW]/day).

Output from Equation 1.

Cfish_filet = Average fish filet concentration consumed by 

humans (mg/kg).

Calculated in the Human 

Health Module.

CRfish = Consumption rate of fish (grams wet weight [g 

ww]/day).

Cohort-specific value.

Ffish = Fraction of fish intake from contaminated 

source.

Assumed value of 1.

 

1 The IRW model includes ten pollutants: arsenic, cadmium, chromium VI, copper, lead, mercury, nickel, selenium, 

thallium, and zinc.

2 To determine the fraction of T3 and T4 fish intake for humans, ERG used data in Table 10-74 of the EPA 

Exposure Factor Handbook: 2011 Edition. The table includes total consumption of freshwater fish, listed by 

species, caught by survey respondents during one season. ERG determined the trophic level of each species and 

calculated a percentage of T4 and T3 fish consumed. See Appendix E, Table E-1 of EPA’s Environmental 

Assessment for the Effluent Limitations Guidelines and Standards for the Steam Electric Power Generating Point 

Source Category (EPA-821-R-15-006) lists the type of fish and assigned trophic level used to estimate percent of T3 

and T4 fish eaten.
Memorandum

September 21, 2015

Page 3

1,000 = Conversion factor (g/kg).

BW = Body weight (kg). Cohort-specific value 

LADD =

ADD × ED × EF

AT × 365

Equation 2

Where:

LADD = Lifetime average daily dose (mg/kg BW/day). Output from Equation 2.

ADD = Daily dose of pollutant from fish consumption 

(mg/kg BW/day).

Output from Equation 1.

ED = Exposure duration for oral ingestion (year 

[yr]).

Cohort-specific value.

EF = Exposure frequency (days/yr). Assumed value of 350.

AT = Averaging time (yr). Standard value of 70.

365 = Conversion factor (days/yr).

The model evaluated the cancer risk (using LADD) and potential to cause non-cancer 

health effects (using ADD) from the consumption of fish for the following cohorts:

 Recreational Fishers

— Adult

— Child, age 1 to < 2 years

— Child, age 2 to < 3 years

— Child, age 3 to < 6 years

— Child, age 6 to < 11 years

— Child, age 11 to < 16 years

— Child, age 16 to < 21 years

 Subsistence Fishers

— Adult

— Child, age 1 to < 2 years

— Child, age 2 to < 3 years

— Child, age 3 to < 6 years

— Child, age 6 to < 11 years

— Child, age 11 to < 16 years

— Child, age 16 to < 21 years

To determine the ADD and LADD from fish consumption, the model used the following 

information:

 Concentration of Pollutant in Fish (T3 and T4) – calculated in the IRW model: 

water quality module for immediate discharge receiving waters. These data were 

not cohort dependent.

 Fish Consumption Rate –Section 2 presents the methodology to select fish 

consumption rates. Section 3 discusses updates for standard cohorts, and Section 

4 presents values for cohorts based on race or Hispanic origin. These data are 

cohort dependent.
Memorandum

September 21, 2015

Page 4

 Body Weight – values provided in the EPA Exposure Factors Handbook: 2011 

Edition (Table A-1, Attachment A). These data are cohort dependent.

 Exposure Duration – values based on time spent in respective cohort (Table A-1, 

Attachment A). These data are cohort dependent.

2. METHODOLOGY TO SELECT FISH CONSUMPTION RATES 

In the U.S., large quantities of finfish and shellfish are caught, both recreationally and 

commercially, for human consumption. Some finfish and shellfish might accumulate

contaminants from the water body or from the food they eat. When residents of nearby water 

bodies eat the fish harvested from contaminated waters, they also are exposed to these 

contaminants based on the amount of fish they consume.

EPA estimates of fish consumption rates among potentially exposed human populations 

are typically based on surveys and studies. This section presents background on how estimates of 

fish consumption rates are developed.

The data collected from fish consumption surveys and studies can be parsed in multiple 

ways to represent the following:

 Population basis (“consumer only” or “per capita,”); see Section 2.1.

 Statistical percentiles (used to represent different population subgroups, such as 

general population, recreational fishers, subsistence fishers, and Native American 

fishers); see Section 2.2.

 Type of fish consumed (finfish, shellfish, or both); see Section 2.3.

 Habitat and salinity (water body type) where fish are caught (freshwater, 

estuarine, marine); see Section 2.3.

 Fish tissue preparation (cooked or uncooked); see Section 2.4.

 Demographic groups (e.g., income, race, or geographic location); see Section 4.

2.1 Population Basis for Fish Consumption Rates

General population studies may include two types of intake data: 1) “consumer only” is 

the average intake across only those individuals that consumed fish and shellfish during the 

survey time period and 2) “per capita” is the average intake across the entire survey population, 

including respondents that did not consume fish or shellfish during the survey time period. In the 

Exposure Factors Handbook: 2011 Edition, EPA noted that per capita intake rates are 

appropriate for use in exposure assessments where average doses across the entire potentiallyexposed population of interest are used, because the average doses represent both individuals that 
Memorandum

September 21, 2015

Page 5

consumed fish during the survey period and individuals who may eat fish sometimes but did not 

consume fish during the survey period. However, use of per capita intakes may underestimate the 

actual exposure to fish consumers. Consumer-only data may be of greater interest in exposure 

analysis and risk assessment applications where impacts to fish consumers are a specific concern.

For the EA and benefits analyses in support of the steam electric ELGs, the focus of 

human exposure to contaminated fish was on recreational and subsistence fishers. Recreational 

fishers are non-commercial, non-subsistence fishers and are more vulnerable to pollutant 

exposure by intake of contaminated fish from a specific water body compared to the general 

population. Subsistence fishers are individuals who consume fresh caught fish as a major food 

source. Intake rates for subsistence fishers are generally higher than for the general population,

and subsistence fishers are more vulnerable to pollutant exposure by intake of contaminated fish 

from a specific water body compared to both recreational fishers and the general population.

At proposal, ERG used per capita fish consumption rates in the IRW model: human

health module. However, because the benefits analysis includes only those populations that are 

recreational and subsistence fishers (i.e., populations that consume fish from receiving waters), 

ERG updated the fish consumption rates in the IRW Model: Human Health Module to reflect 

fish consumption rates based on consumer-only data. See Section 3 and Section 4 for details on 

the fish consumption rates used for the standard cohorts and cohorts based on race or Hispanic 

origin, respectively.

2.2 Statistical Percentiles for Fish Consumption Rates

Statistical percentiles (percentiles) indicate the value below which a percentage of data 

fall. For example, the 90th percentile is the value below which 90 percent of the data points may 

be found. The EPA document, Methodology for Deriving Ambient Water Quality Criteria for the 

Protection of Human Health (Table 5-1) [U.S. EPA, 2000] determined protective fish intake 

rates using the following percentiles by fisher type:

 General population and recreational fisher: 90th percentile of per capita data.

 Subsistence fisher: 99th percentile of per capita data.

Use of a consumer-only dataset, however, would require the selection of lower 

percentiles to represent recreational and subsistence fishers (because a consumer-only survey 

should yield higher fish intake rates than a corresponding per capita survey). The EPA document,

Methodology for Deriving Ambient Water Quality Criteria for the Protection of Human Health

[U.S. EPA, 2000] does not provide recommendations for the statistical percentiles of consumeronly intake rates that would best represent recreational and subsistence fishers. ERG used best 

professional judgment and selected the following percentiles by fisher type:

 Recreational fisher: mean3of consumer-only data.

 

3 The data available in EPA’s Exposure Factor Handbook: 2011 Edition provided mean fish consumption rates, 

rather than median fish consumption rates.
Memorandum

September 21, 2015

Page 6

 Subsistence fisher: 95

th percentile of consumer-only data.

2.3 Type of Fish Consumed and Habitat for Fish Consumption Rates

Fish consumption rates may be divided into types of fish (finfish and shellfish) and into 

habitat and salinity type (freshwater, estuarine, or marine). Table 2-1 shows typical finfish and 

shellfish found in freshwater, estuarine, and marine water bodies. The IRW model: water quality 

module quantified the environmental risks within freshwater habitats, specifically rivers/streams 

and lakes/ponds/reservoirs. Shellfish species are more commonly found in marine and estuarine 

environments; only two shellfish species were common in freshwater environments, as shown in 

Table 2-1. Based on the model capabilities and water bodies represented, ERG chose to use fish 

consumption rates based on finfish only (where available) and/or on freshwater/estuarine habitats

(where available).

2.4 Fish Tissue Preparation for Fish Consumption Rates

Fish consumption rates are also presented as uncooked or cooked (i.e., “as-prepared”) 

fish. ERG used the consumption rates based on uncooked fish weight. As detailed in EPA’s 

Exposure Factors Handbook: 2011 Edition, contaminant concentrations in fish are generally 

measured in the uncooked samples. Cooking of the fish results in moisture loss and reduction in 

fish weight, and the moisture loss varies based on the cooking method used. Because the mass of 

the contaminant in the fish tissue remains constant, the contaminant concentration in the cooked 

fish tissue will increase. To ensure comparison on the same basis, ERG used uncooked fish 

consumption rates.

Table 2-1. Type of Fish Consumed by Humans by Habitat and Salinity (Water Body Type)

Freshwater Estuarine Marine

Finfish Shellfish Finfish Shellfish Finfish Shellfish

Carp

Catfish

Cisco

Eel

Perch

Pike

Roe

Salmon

Smelts, Rainbow

Sturgeon

Trout

Whitefish

Crayfish

Snails

Anchovy

Catfish

Croaker

Eel

Flatfish

Flounder

Halibut

Herring

Mackerel

Mullet

Perch

Pompano

Rockfish

Roe

Salmon

Shad

Shark

Smelts

Clam

Crab

Lobster

Mussels

Octopus

Oyster

Scallop

Shrimp

Snails

Barracuda

Cod

Flatfish

Haddock

Halibut

Herring

Mackerel

Ocean Perch

Pollock

Pompano

Porgy/Scup

Roe

Salmon

Sardine

Sea Bass

Shad

Shark

Smelts

Abalone

Clam

Conch

Crab

Lobster

Mussels

Octopus

Scallop

Shrimp

Snails

Squid
Memorandum

September 21, 2015

Page 7

Table 2-1. Type of Fish Consumed by Humans by Habitat and Salinity (Water Body Type)

Freshwater Estuarine Marine

Finfish Shellfish Finfish Shellfish Finfish Shellfish

Smelts, Rainbow

Sturgeon

Trout

Snapper

Swordfish

Tuna

Whitefish

Whiting

Sources: U.S. EPA, 2011. Exposure Factors Handbook: 2011 Edition. EPA-600-R-09-052F. (September) and U.S.

EPA, 2014. Estimated Fish Consumption Rates for the U.S. Population and Selected Subpopulations (NHANES 

2003-2010). EPA-820-R-14-002. (April).

3. FISH CONSUMPTION RATES USED FOR STANDARD COHORTS

This section details the updated fish consumption rates for the IRW model: human health 

module standard cohorts. Table 10-1 of the Exposure Factors Handbook: 2011 Edition includes 

per capita and consumer-only fish intake rates based on EPA analysis of the National Health and 

Nutrition Examination Survey (NHANES) data from 2003 to 2006. As discussed in Section 2.1, 

ERG revised the fish consumption rates to be based on consumer-only data, rather than per 

capita data. Table 3-1 presents, by cohort, the fish consumption rates used at proposal and the 

fish consumption rates used for the final rule.4

 

4 ERG also examined a document published by EPA in April of 2014 (U.S. EPA, 2014) that provides consumption 

rates using NHANES data from 2003 to 2010; however, the document presents fish consumption rates on a per 

capita basis only; therefore, ERG did not use the document for fish consumption rate updates. 
Memorandum

September 21, 2015

Page 8

Table 3-1. Fish Consumption Rates (Uncooked) for the IRW Model: Human Health 

Module (Standard Cohorts)

Receptor Cohort

Consumption Rate Used for 

Proposed Rule (per capita)

Consumption Rate Used for Final 

Rule (consumer only)

CRfish, 

g/day Reference

CRfish, 

g/day Reference

Recreational

1 to <2 years 2.5 Table 10-1 of (a): Mean, 

per capita fish intake for

finfish (excludes 

shellfish).

1

18.2 Table 10-1 of (a): Mean, 

consumer-only fish intake 

for finfish (excludes 

shellfish).

1

2 to <3 years 3 22.1

3 to <6 years 3.5 24.2

6 to <11 years 5.1 35.0

11 to <16 years 5.7 37.5

16 to <21 years 7.2 47.3

Adult 20 Table 10-5 of (a).

2 53.2 Table 10-1 of (a): Mean, 

consumer-only fish intake 

for finfish (excludes 

shellfish).

1,4

Subsistence

1 to <2 years 13.7 Table 10-1 of (a): 95th 

percentile, per capita fish 

intake for finfish (excludes 

shellfish).

1

55.9 Table 10-1 of (a): 95th 

percentile, consumer-only 

fish intake for finfish 

(excludes shellfish).

1

2 to <3 years 16.6 67.6

3 to <6 years 26 67.0

6 to <11 years 35 92.2

11 to <16 years 39.8 96.6

16 to <21 years 50.1 121.7

Adult 88 Table 10-6 of (a).

3 164.0 Table 10-1 of (a): 95th 

percentile, consumer-only 

fish intake for finfish 

(excludes shellfish).

1,4

a U.S. EPA, 2011. Exposure Factors Handbook: 2011 Edition. EPA-600-R-09-052F. (September).

1 Values provided as g/kg-day. ERG multiplied values in Table 10-1of the reference by cohort body weight to 

calculate a consumption rate as g/day.

2 Table 10-5 includes freshwater recreational fish consumption rates from eight studies at eight U.S. locations. For 

proposal, ERG used mean values for "all respondents." See ERG memorandum, “Fish Consumption Rate for 

Cohorts for the Steam Electric ELGs Environmental Assessment” (DCN SE01963).

3 Table 10-6 includes Native American fish consumption rates from seven studies for ten locations/Tribes. For 

proposal, ERG used mean values for adults. See ERG memorandum, “Fish Consumption Rate for Cohorts for the 

Steam Electric ELGs Environmental Assessment” (DCN SE01963).

4 Use average fish intake for two age categories: 1) 21 to <50 years and 2) 50+ years.

4. FISH CONSUMPTION RATES USED FOR COHORTS BASED ON RACE OR HISPANIC ORIGIN

The EPA website defines EJ and Agency goals as, “the fair treatment and meaningful 

involvement of all people regardless of race, color, national origin, or income with respect to the 

development, implementation, and enforcement of environmental laws, regulations, and policies. 

EPA has this goal for all communities and persons across this Nation. It will be achieved when 
Memorandum

September 21, 2015

Page 9

everyone enjoys the same degree of protection from environmental and health hazards and equal 

access to the decision-making process to have a healthy environment in which to live, learn, and 

work.” To help achieve the Agency goals, ERG examined both the impacts of income and race 

on fish consumption rates.

4.1 EJ Factor: Income Demographic

ERG examined the impacts of income on fish consumption rates using the EPA 

document Estimated Fish Consumption Rates for the U.S. Population and Selected 

Subpopulations (NHANES 2003-2010) [U.S. EPA, 2014].

5 This document included finfish 

consumption rates for low income populations. The rates provided in the document are divided 

into two age groups: adults (21 years and older) and youth (<21 years). Table B-1 (Attachment 

B) presents the consumption rates by income demographic. The consumption rates are based on 

general population data (i.e., per capita data and not limited to consumers only); therefore, ERG 

used the 90th percentile to represent recreational fishers and the 99th percentile to represent 

subsistence fishers. Because the fish consumption rates are based on per capita data, the 

consumption rates for the income groups (adult and child cohorts) are lower than the 

recommended updated consumption rates presented in Table 3-1 for standard cohorts.

To examine further, ERG plotted the fish consumption rates by increasing income to 

identify any trends (Figure B-1, Attachment B). The data suggest that national consumption rates 

tend to increase with increased income for adults. For child cohorts, there does not appear to be a 

strong correlation between income and fish consumption rate. Based on this analysis, an EJ 

analysis that defines cohorts according to income demographics is not likely to reveal 

disproportionate impacts among low-income communities as a result of fish consumption. 

Therefore, ERG did not include cohorts based on income demographics in the IRW model: 

human health module.

4.2 EJ Factor: Race or Hispanic Origin

ERG used the Exposure Factors Handbook: 2011 Edition [U.S. EPA, 2011] to determine 

if fish consumption rates vary according to race or Hispanic origin.

6 This document includes 

consumer-only fish consumption rates by the following population groups: Non-Hispanic Black, 

Non-Hispanic White, Mexican-American, Other Hispanic, and Other, including multiple races. 

 

5 ERG also examined the reference Estimated Per Capita Fish Consumption in the United States, August 2002. 

Office of Water, Engineering and Analysis Division. This document, however, does not provide consumption rates 

by age group. Because more recent data were available and fish consumption rates were not provided by age for the 

cohorts, ERG did not use this reference as a source of consumption rates for low income cohorts.

6 ERG also examined the EPA document Estimated Fish Consumption Rates for the U.S. Population and Selected 

Subpopulations (NHANES 2003-2010) [U.S. EPA, 2014]. This document included fish consumption rates for the 

same race/Hispanic origin groups as listed in Table 4-1. The 2014 document divided fish consumption rates into two 

age groups: adults (21 years and older) and youth (<21 years). The consumption rates were based on general 

population data (i.e., per capita data). Because these data were not based on consumers only, ERG decided to use the

fish consumption rates from the Exposure Factors Handbook: 2011 Edition, presented in Table 4-1. 
Memorandum

September 21, 2015

Page 10

Because the consumption rates are based on consumer-only intake, ERG used the mean 

consumption rate to represent recreational fishers and the 95th percentile to represent subsistence 

fishers. Table 4-1 presents the consumption rates as grams per day (g/day). As with the fish 

consumption rates in Table 3-1, the consumption rates are based on EPA analysis of NHANES 

data 2003 through 2006.

The Exposure Factors Handbook: 2011 Edition [U.S. EPA, 2011] includes fish 

consumption rates as grams per kilogram body weight per day (g/kg-day) for each race or 

Hispanic origin regardless of the cohort age (a single value represents all ages). ERG multiplied 

the fish consumption rate for the race or Hispanic origin by the body weight of each cohort (body 

weight varies by age). This resulted in a fish consumption rate in grams per day for each cohort 

by race or Hispanic origin and by age. See Table A-1 in Attachment A. Because the fish 

consumption rates by race or Hispanic origin represent all ages, the values presented in Table 4-1

might not be directly comparable to fish consumption rates for standard cohorts, as presented in 

Table 3-1.

Based on the national fish consumption rates in Table 4-1, an EJ analysis that defines 

cohorts according to race and Hispanic origin suggests potential disproportionate impacts among 

minority communities as a result of fish consumption. Therefore, ERG included cohorts based on 

race or Hispanic origin in the IRW model: human health module. 
Memorandum

September 21, 2015

Page 11

Table 4-1. Fish Consumption Rates (Uncooked) by Race or Hispanic Origin

Receptor

Race or Hispanic 

Origin

Reference/ 

Statistical 

Value

CRfish, 

g/kg-day

(All ages)

Consumption Rate (CRfish), g/day, by Cohort1

1 to <2 

years

2 to <3 

years

3 to <6 

years

6 to <11 

years

11 to <16 

years

16 to <21 

years Adult

Recreational

Non-Hispanic White

Table 10-8 of 

(a): Mean, 

consumer-only 

fish intake for 

finfish 

(excludes 

shellfish).

0.67 7.6 9.2 12.5 21.3 38.1 48 53.6

Non-Hispanic Black 0.77 8.8 10.6 14.3 24.5 43.7 55.1 61.6

Mexican-American 0.93 10.6 12.8 17.3 29.6 52.8 66.6 74.4

Other Hispanic 0.82 9.3 11.3 15.3 26.1 46.6 58.7 65.6

Other, including 

Multiple Races

0.96 10.9 13.2 17.9 30.5 54.5 68.7 76.8

Subsistence

Non-Hispanic White Table 10-8 of 

(a): 95th

Percentile, 

consumer-only 

fish intake for 

finfish 

(excludes 

shellfish).

1.9 21.7 26.2 35.3 60.4 107.9 136 152

Non-Hispanic Black 2.1 23.9 29 39.1 66.8 119.3 150.4 168

Mexican-American 2.8 31.9 38.6 52.1 89 159 200.5 224

Other Hispanic2 2.7 30.8 37.3 50.2 85.9 153.4 193.3 216

Other, including 

Multiple Races2

3.6 41 49.7 67 114.5 204.5 257.8 288

a U.S.EPA, 2011. Exposure Factors Handbook: 2011 Edition. EPA-600-R-09-052F. (September).

1 Values provided as g/kg-day. ERG multiplied values in Table 10-8 of the reference by cohort body weight to calculate a cohort-specific consumption rate as 

g/day.

2 Estimates are less statistically reliable based on guidance when using NHANES data.
Memorandum

September 21, 2015

Page 12

5. REFERENCES

1. U.S. EPA. 2000. Guidance for Assessing Chemical Contaminant Data for Use in Fish 

Advisories. Volume 1: Fish Sampling and Analysis. EPA-823-B-00-007. Office of 

Water. Washington, DC. (November).

2. U.S. EPA. 2002. Estimated Per Capita Fish Consumption in the United States. EPA-821-

C-02-003. Office of Water. Washington, DC. (August).

3. U.S. EPA. 2011. Exposure Factors Handbook: 2011 Edition. EPA-600-R-09-052F. 

Office of Research and Development. Washington, DC. (September). DCN SE01912.

4. U.S. EPA. 2013. Environmental Assessment for the Proposed Effluent Limitations 

Guidelines and Standards for the Steam Electric Power Generating Point Source 

Category. EPA-821-R-13-003. Office of Water. Washington, DC. (April).

5. U.S. EPA. 2014. Estimated Fish Consumption Rates for the U.S. Population and Selected 

Subpopulations (NHANES 2003-20010). EPA-820-R-14-002. (April).
Attachment A

September 21, 2015

Page A-1

ATTACHMENT A: BODY WEIGHT AND EXPOSURE DURATION

To calculate the average daily dose and lifetime average daily dose, the IRW model: 

human health module used cohort-specific body weights (BW) and cohort-specific exposure 

durations (ED). Table A-1 presents the values used in the model.

Table A-1. Body Weight and Exposure Duration for the IRW Model: Human Health 

Module

Receptor Cohort

Body Weight Exposure Duration

BW, kg Reference ED, yr Reference

Recreational

1 to <2 years 11.4 Table 8-1 of (a) 1 Set equal to time in 

cohort. 2 to <3 years 13.8 1

3 to <6 years 18.6 3

6 to <11 years 31.8 5

11 to <16 years 56.8 5

16 to <21 years 71.6 5

Adult 80 49

Subsistence

1 to <2 years 11.4 1

2 to <3 years 13.8 1

3 to <6 years 18.6 3

6 to <11 years 31.8 5

11 to <16 years 56.8 5

16 to <21 years 71.6 5

Adult 80 49

a U.S.EPA, 2011. Exposure Factors Handbook: 2011 Edition. EPA-600-R-09-052F. (September).
Attachment B

September 21, 2015

Page B-1

ATTACHMENT B: COMPARISON OF NATIONAL FISH CONSUMPTION RATES BY 

INCOME

As discussed in Section 4.1, ERG reviewed fish consumption rates by income. Table B-1 

presents the data reported in the EPA document, Estimated Fish Consumption Rates for the U.S. 

Population and Selected Subpopulations (NHANES 2003-2010) [U.S. EPA, 2014]. ERG also 

plotted the fish consumption rates by income in Figure B-1. Based on this review, ERG determined 

that income demographics do not suggest a disproportionate impact among low-income 

communities as a result of fish consumption.

Table B-1. Fish Consumption Rates (Uncooked) by Income Demographics

Receptor Cohort Income, $

Consumption Rate 

(CRfish), g/day Reference/Statistical Value

Recreational

Adult

0 - <20,000 35.4 Table 11a of (a): 90th percentile, 

per capita fish intake for finfish 

(excludes shellfish).

20,000 - <45,000 36.1

40,000 - <75,000 37.7

≥75,000 44.1

>20,000 b 38.9

Refused/Don't know c 43.6

Income Missing c 28.8

Child

(<21 yrs)

0 - <20,000 20.0 Table 22a of (a): 90th percentile, 

per capita fish intake for finfish 

(excludes shellfish).

20,000 - <45,000 17.1

40,000 - <75,000 21.9

≥75,000 16.8

>20,000 b 12.7

Refused/Don't know 23.1

Income Missing 26.4

Subsistence

Adult

0 - <20,000 78.0 Table 11a of (a): 99th percentile, 

per capita fish intake for finfish 

(excludes shellfish).

20,000 - <45,000 75.0

40,000 - <75,000 78.3

≥75,000 84.4

>20,000 b 81.4

Refused/Don't know 87.4

Income Missing 75.7

Child

(<21 yrs)

0 - <20,000 50.9 Table 22a of (a): 99th percentile, 

per capita fish intake for finfish 

(excludes shellfish).

20,000 - <45,000 48.5

40,000 - <75,000 64.9

≥75,000 43.7

>20,000 b 32.7

Refused/Don't know 73.3

Income Missing 65.3
Attachment B

September 21, 2015

Page B-2

a U.S.EPA. 2014. Estimated Fish Consumption Rates for the U.S. Population and Selected Subpopulations (NHANES 

2003-2010). EPA-820-R-14-002. (April).

b The “>20,000” income group appears to be a separate group where the respondent did not want to be more specific on 

their income. 

Figure B-1. Fish Consumption Rates By Income 

Adult

Recreational

Child 

Recreational

Adult

Subsistence 

Child

Subsistence

0

10

20

30

40

50

60

70

80

90

0 - <20,000 20,000 - <45,000 40,000 - <75,000 ≥75,000

Fish Consumption Rate, g/day

Income, $