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2020 National Emissions Inventory Technical
Support Document: Miscellaneous Non-
Industrial NEC: Cremation - Human and
Animal


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EP A-454/R-23 -001 cc
March 2023

2020 National Emissions Inventory Technical Support Document: Miscellaneous Non-Industrial

NEC: Cremation - Human and Animal

U.S. Environmental Protection Agency
Office of Air Quality Planning and Standards
Air Quality Assessment Division
Research Triangle Park, NC


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Contents

List of Tables	i

29	Miscellaneous Non-Industrial NEC: Cremation - Human and Animal	29-1

29.1	Sector Descriptions and Overview	29-1

29.2	EPA-developed estimates	29-1

29.2.1	Activity data	29-1

29.2.2	Allocation procedure	29-2

29.2.3	Emission factors	29-2

29.2.4	Controls	29-5

29.2.5	Emissions	29-5

29.2.6	Sample calculations	29-6

29.2.7	Improvements/Changes in the 2020 NEI	29-9

29.2.8	Puerto Rico and U.S. Virgin Islands	29-9

29.3	References	29-9

List of Tables

Table 29-1: Human and animal cremation SCCs	29-1

Table 29-2: Human cremation rate by state	29-3

Table 29-3: Emissions factors for the cremation of human and animal blood and tissues	29-3

Table 29-4: Estimated amount of material in restored teeth	29-4

Table 29-5: Sample calculations for mercury emissions from human cremation for the 85+ age group and
cremation of cats in Clark County, ID	29-7

l


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29 Miscellaneous Non-Industrial NEC: Cremation - Human and Animal

29.1 Sector Descriptions and Overview

The cremation of human remains results in emissions of particulate matter, S02, NOx, VOC, CO, and HAPs. It is a
significant source of mercury emissions, due to mercury in dental fillings, as well as mercury in blood and
tissues. In 2020, human cremation resulted in the emissions of approximately 1.8 tons of mercury.

The cremation of animals also results in emissions of CAPs and HAPs, though it emits less mercury than human
cremation. In 2020, animal cremation resulted in the emissions of approximately 2 lbs. of mercury.

SCCs for human and animal cremation are provided in Table 29-1.

Table 29-1: H uman and animal cremation SCCs

see

see Level 1

SCC Level 2

SCC Level 3

SCC Level 4

2810060100

Miscellaneous Area Sources

Other Combustion

Cremation

Humans

2810060200

Miscellaneous Area Sources

Other Combustion

Cremation

Animals

A list of agencies that submitted human and/or animal cremation emissions is provided in Section 6.2.3.

29.2 EPA-developed estimates

The calculations for estimating emissions from human cremation involve estimating the number of deaths in
each age group in each county, using data from the Centers for Disease Control and Prevention. The number of
deaths is multiplied by the average weight by age group and the state-level cremation rate from the National
Funeral Directors Association to estimate the total amount of cremations in each county in terms of mass. This
number is multiplied by an emissions factor to estimate the emissions of CAPs and HAPs. Emissions of mercury
include emissions from mercury in fillings in teeth and in blood and tissues. The emissions from mercury in
fillings are estimated based on data on the number of filled teeth per person in each age group and assumptions
about the proportion of fillings that contain mercury and the amount of mercury in each filling.

The calculations for estimating emissions from animal cremation involve determining the number of cremated
animals nationally and distributing this number to each county based on population. The number of cremated
animals is multiplied by average weights for cats and dogs to determine the amount of cremations in each
county in terms of mass. This number is multiplied by an emissions factor to estimate the emissions of CAPs and
HAPS.

29.2.1 Activity data
Human Cremation

The activity data for human cremation is based on the number of deaths in each county in 13 age groups, from
the Centers for Disease Control and Prevention WONDER database [ref 1], Data for some counties are withheld
in the WONDER database. These gaps are filled using the data on the total number of deaths by age group in
each state (which includes the number of deaths that are withheld at the county level). First, the sum of the
reported county-level number of deaths in each age group and state is subtracted from the reported state-level

29-1


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number of deaths in each age group to determine the total number of deaths withheld at the county level in
each state and age group.

Deaths_withheldsa = Deaths_statesa — ^ Deaths_countysa

Where:

Deaths_withhelds,a = Total number of withheld deaths in state s in age group a
Deaths_states,a = Total number of deaths reported at the state level in state s in age group a
Deaths_countys,a = Total number of deaths reported at the county level in state s in age group a

The total number of withheld deaths are distributed to the counties based on the proportion of population in
those counties to the total state population.

Pop_ratioc =	(H2)

Where:

Pop_ratioc = The population ratio used to distribute withheld deaths in state s to county c
Popc = The total population of county c
Pops = The total population of state s

The number of withheld deaths in each state is multiplied by the county population ratio to distribute the
withheld deaths to the counties. Note that this step is only performed for counties where county-level data on
number of deaths is withheld; this step is not performed where county-level data on deaths is reported.

Deathsc a = Deaths_withheldsa x Pop_ratioc	(H3)

Where:

Deathsc,a	= The number of deaths in county c in age group a

Deaths_withhelds,a = Total number of withheld deaths in state s in age group a, from equation HI
Pop_ratioc	= The population ratio used to distribute withheld deaths in state s to county c,

from equation H2

The total number of deaths in each county (either reported directly in the CDC WONDER database or estimated
using equation H3) is multiplied by a state-level cremation rate, reported by the National Funeral Directors
Association (NFDA) [ref 2], shown in Table 29-2. It is assumed that the state-level cremation rate applies to all
counties within the state.

Cremationsc a = Deathsca x Cremations ate s	(H4)

Where:

Cremationsc,a = The number of human cremations in county c in age group a
Deathsc,a	= The number of deaths in county c in age group a

Cremation_rates = The rate of human cremations in state s, from Table 29-2 [ref 2]

29-2


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Table 29-2: Human cremation rate by state

State

Cremation Rate

Alabama

23.1%

Alaska

66.3%

Arizona

66.1%

Arkansas

32.7%

California

63.4%

Colorado

68.6%

Connecticut

50.3%

Delaware

46.2%

District of Columbia

40.0%

Florida

62.4%

Georgia

37.1%

Hawaii

72.7%

Idaho

56.8%

Illinois

42.8%

Indiana

36.6%

Iowa

42.2%

Kansas

44.6%

Kentucky

24.5%

Louisiana

26.3%

Maine

70.0%

Maryland

40.6%

Massachusetts

43.4%

Michigan

54.9%

Minnesota

57.2%

Mississippi

18.2%

Missouri

39.7%

Montana

72.8%

Nebraska

43.8%

Nevada

76.9%

New Hampshire

70.3%

New Jersey

40.6%

New Mexico

58.9%

New York

39.6%

North Carolina

39.8%

North Dakota

35.3%

Ohio

42.3%

Oklahoma

39.0%

Oregon

74.1%

Pennsylvania

43.1%

Rhode Island

46.6%

South Carolina

37.4%

South Dakota

35.4%

Tennessee

28.1%

Texas

39.3%

Utah

31.2%

Vermont

67.3%

Virginia

36.1%

Washington

75.5%

West Virginia

27.3%

Wisconsin

52.5%

Wyoming

66.7%

29-3


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The CDC provides estimates of the average weight of individuals in each age group [ref 3], This number
is multiplied by the number of cremations in each county in each age group and then summed across all
age groups to estimate the total amount of cremations in tons in each county.

A

Cremations _tonsc

Z1 ton

Cremationsr n x W„ x	—

a 2<00() Ws

(H5)

a = 1

Where:

Cremations_tonsc= The weight of humans cremated in county c, in tons
CremationSc = The number of human cremations in county c, from equation H4

= The average weight of individuals from age group a

Animal Cremation

The Pet Loss Professionals Alliance (PLPA) conducted a survey that estimated that there were 1,840,965
pet cremations in 2012, and that 99 percent of deceased pets are cremated [ref 4], In addition, the
Humane Society of the United States estimates that there are 2,700,000 adoptable dogs and cats
euthanized in animal shelters each year [ref 5], It is assumed that all of these shelter animals are
cremated. Therefore, there are a total of approximately 4,540,965 animal creations each year. Note that
this estimate does not double count the number of animal cremations, because the PLPA study counts
the number of cremations of pets—i.e. animals that are owned by people—whereas the Humane
Society estimates are for animals in shelters that were not adopted.

The population of cats and dogs is approximately 52.5 percent cats and 48.5 percent dogs [ref 5], Using
this percentage and the total number of pets and shelter animals cremated annually, a total number of
cats and a total number of dogs cremated annually can be calculated.

Cremationsc/d us = Ratioc/d x (Cremations_petsus + Cremations_shelterus)	(Al)

Cremations_pets us = Total number of pets cremated annually in the United States
Cremations_shelter us = Total number of shelter animals cremated annually in the United States

The average weight of a domestic cat is approximately 4.5 kg (9.9 pounds) [ref 6], The average weight of
a dog is difficult to determine due to large differences in breeds, but an average across breeds is 48.5
pounds [ref 7].- Note that this is a straight average of the average adult weight for male and female dogs
across breeds. It is not a weighted average that takes into account the popularity of different breeds in
the United States. To calculate the weight, in tons, of both cats and dogs cremated annually, the average
weight values are multiplied by the total number of cats and total number of dogs cremated annually.

Where:

CremationSc/d

RatiOc/d

= Total cats, c, or dogs, d, cremated annually in the United States
= Ratio of cats, c, or dogs, d, in the pet population

Cremations_tonsc/d = Cremationsc/d x Weightc/d x

1 ton

(A2)

2,000 pounds

29-1


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Where:

Cremations_tonsc/d,us = Total weight, in tons, of cats, c, or dogs, d, cremated annually in the

United States

Cremationsc/d,us	= Total cats, c, or dogs, d, cremated annually in the United States

Weightc/d	= Average weight per animal, in pounds, of cats, c, or dogs, d

Once the weight of cats and weight of dogs cremated annually has been calculated, these values can be
summed to derive a total weight of animals cremated annually.

Cremations _tonsanimai = Cremations _tonsc + Cremations _tonsd	(A3)

Where:

Cremations_tonsa„imai,us= Total weight of animals cremated annually in the United States, in tons
Cremations_tonsc,us = Total weight of cats, c, cremated annually in the United States, in tons
Cremations_tonsd,us = Total weight of dogs, d, cremated annually in the United States, in tons

29.2.2	Allocation procedure
Human Cremation

The number of deaths is reported by the CDC at the county level. Therefore, these data do not need to
be allocated. For counties with withheld data on the number of deaths, the total number of withheld
deaths is distributed to counties based on the proportion of population in those counties, as described
in equations H1-H3.

Animal Cremation

The estimated national-level total weight of animals cremated are allocated to the county level based on
the ratio of population in each county to the total national population.

Popc

Cremations_tonsanimal c Cremations_tonsanimal,us ^ ~q	(Al)

r°PuS

Where:

Cremations_tonsa„imai,c = Total weight of animals cremated in county c, in tons
Cremations_tonsa„imai,us= Total weight of animals cremated annually in the United States, in tons,

from equation A3
Popc	= The total population of county c

Popus	= The total population of the United States

29.2.3	Emission factors

Human and Animal Cremation - Blood and Tissues

The emissions factors for human and animal cremation for CAPs are from AP-42 [ref 8], and a report by
EPA on emissions tests of a crematory [ref 9] and are in units of pounds of emissions per ton cremated.
The emission factors for CAPs are also provided in the "Wagon Wheel Emission Factor Compendium" on
the 2020 NEI Supporting Data and Summaries site. The emissions factors for most HAPs are a report

29-2


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from the California Air Resources Board [ref 10], as well as from the EPA emissions test of a crematory.
The VOC HAPs are computed in EIS using HAP Augmentation factors available in the zip file
"HAPAugmentation_Nonpoint_28jan2023", on the 2020 NEI Supplemental data FTP site. The mercury
emissions factor is from a review of multiple studies [ref 11], These emission factors do not include
emissions from dental fillings. As shown in Table 29-3, EPA uses the same emissions factors for
emissions from cremation of blood and tissues for both humans and animals.

Table 29-3: Emissions factors for the cremation of human and animal blood and tissues

Pollutant

Pollutant Code

Emission
Factor
(lbs/ton)

Source

Carbon Monoxide

CO

2.947

8

Lead

7439921

0.009

9

Nitrogen Oxides

NOX

3.560

8

PM10 Primary

PM10-PRI

3.036

8 (65% of total PM)

PM2.5 Primary

PM25-PRI

2.022

8 (43.3% of total
PM)

Sulfur Dioxide

S02

2.173

8

Volatile Organic
Compounds

VOC

0.299

8

Acenaphthene

83329

1.303E-06

10

Acenaphthylene

208968

8.971E-07

10

Acetaldehyde

75070

9.269E-04

10

Anthracene

120127

2.389E-06

10

Arsenic

7440382

5.097E-04

10

Benzo(a)anthracene

56553

1.166E-07

10

Benzo(a)pyrene

192972

4.720E-07

10

Benzo(b)fluoranthene

205992

1.737E-07

10

Benzo(g,h,i)perylene

191242

5.874E-07

10

Benzo(k)fluoranthene

207089

1.486E-07

10

Beryllium

7440417

1.760E-05

10

Cadmium

7440439

2.940E-03

9

Chromium (VI)

18540299

1.829E-04

10

Chrysene

218019

2.880E-07

10

Cobalt

7440484

8.869E-05

10

Dibenz(a,h)anthracene

53703

1.349E-07

10

Fluoranthene

206440

1.337E-06

10

Fluorene

86737

3.760E-06

10

Formaldehyde

50000

2.469E-04

10

Hydrogen Chloride

7647010

3.595E+00

9

Hydrogen Fluoride

7664393

8.651E-03

10

lndeno(l,2,3-cd)pyrene

193395

1.440E-07

10

Mercury

7439976

1.324E-04

10

29-3


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Pollutant

Pollutant Code

Emission
Factor
(lbs/ton)

Source

Naphthalene

91203

7.520E-04

10

Nickel

7440020

4.149E-04

10

Phenanthrene

85018

1.531E-05

10

Pyrene

129000

1.474E-06

10

Selenium

7782492

4.971E-04

10

Human Cremation - Dental Mercury

In addition to mercury emitted from the cremation of blood and tissues, mercury is also emitted due to
the cremation of dental fillings. The Bay Area Air Quality Management District (BAAQMD) issued a
report in 2012 estimating the average amount of mercury in teeth per person for ten age groups, based
on data from CDC's National Health and Nutrition Examination Survey [ref 12]. Table 29-4 shows the
estimated amount of material in restored teeth by age group from the BAAQMD study [ref 12], which is
matched to the age groups used by the CDC Wonder database, which is the source of data on deaths by
age group.

The BAAQMD memorandum is used to estimate that 31.6 percent of filled teeth in the 5-24 age groups
contain amalgam. According to the American Dental Association (ADA 1998) more than 75 percent of
restorations before the 1970s used dental amalgam, which declined to 50 percent by 1991. Using these
numbers, it is assumed that 50 percent of the filled teeth for 25-44 age groups contain amalgam, 62.5
percent of filled teeth in the 45-64 age group, and 75 percent of filled teeth for people over 65. The
Food and Drug Administration has discouraged the use of dental amalgam in children under 6 [ref 13],
While EPA does not have data on the percent of fillings containing dental amalgam for the 1-4 age
group, it is assumed that this age group has approximately half the dental amalgam of the other age
groups under 20 years old. It is also assumed that children under the age of 1 have no dental mercury.
The analysis also assumes that 45 percent of all amalgam-containing fillings are mercury, based on
information from the Food and Drug Administration [ref 13].

Table 29-4: Estimated amount of material in restored teeth

Age Groups in CDC
WONDER Database

Age Groups in BAAQMD
Memorandum

Avg. Material in
Restored Teeth (g)

% of Fillings
Containing Mercury

< 1 year

0-4 years+

0.000

0.0%

1-4 years

0.160

15.8%

5-9 years

5-14 years

0.720

31.6%

10-14 years

15-19 years

15-24 years

1.070

31.6%

20-24 years

25-34 years

25-34 years

2.230

50.0%

35-44 years

35-44 years

3.290

50.0%

45-54 years

45-54 years

4.310

62.5%

55-64 years

55-64 years

4.320

62.5%

65-74 years

65-74 years

3.780

75.0%

29-4


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Age Groups in CDC
WONDER Database

Age Groups in BAAQMD
Memorandum

Avg. Material in
Restored Teeth (g)

% of Fillings
Containing Mercury

75-84 years

75-84 years

3.650

75.0%

85+ years

85+ years

2.960

75.0%

The emissions factor for mercury in teeth is calculated by multiplying the average amount of material in
restored teeth per person by the percentage of fillings containing mercury in each age group and the
proportion of mercury in dental amalgam (approximately 45 percent).

lb

EF_teethHg a = Materiala x ContainHga x HgProportion x 0.0022—	(H6)

Where:

EF_teethHg,a

Materiala

ContainHga

HgProportion

29.2.4	Controls
There are no controls assumed for this source category.

29.2.5	Emissions
Human Cremation

To estimate the emissions of CAPs from human cremation, the total number of human cremations in
each county, in tons, is multiplied by the emissions factor for each pollutant, from Table 29-3.

Emissionsp c = Cremation_tonsc x EFp	(H7)

Where:

Emissionsp c = Emissions of pollutant p from human cremation in county c, in pounds

Cremations_tonsc= The number of human cremations in county c, in tons

EFP	= Emissions factor for pollutant p from human cremation, in lbs. per ton

The emissions from mercury in teeth are estimated based on the number of cremations rather than the
weight. To estimate the emissions of mercury from teeth during human cremation, the number of
cremations in each age group is multiplied by the emissions factor for each age group and then summed
across age groups.

A

Emissions_teethHg c = ^ Cremationsca x EF _teethHg a	(H8)

a = 1

Where:

= Emission factor for mercury emissions from teeth due to cremation for age

group a, in lbs. per cremation
= The average amount of material in restored teeth for age group a, in grams,
from Table 29-4

= The proportion of people in age group a with fillings that contain mercury, from
Table 29-4

= The proportion of dental amalgam that is mercury (approximately 45 percent)

29-5


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Emissions_teethHg,c = Emissions of mercury in teeth from human cremation in county c, in pounds
Cremationsc,a = The number of human cremations in county c in age group a
EF_teethHg,a	= Emissions factor for mercury emissions from teeth due to cremation for age

group a, in lbs. per cremation

The emissions from mercury from blood and tissues are estimated by multiplying the total number of
cremations in each county, in tons, by the emissions factor for mercury from blood and tissues.

Emissions_tissueHgc = Cremations_tonsc x EF_tissueHg	(H9)

Where:

Emissions_tissueHg,c= Emissions of mercury in tissues from human cremation in county c, in
pounds

Cremations_tonsc = The number of human cremations in county c, in tons
EF_tissueHg,a	= Emissions factor for mercury emissions from blood and tissues due to

cremation for in lbs. per ton

The total emissions of mercury from cremation in each county is calculated by adding the emissions of
mercury from teeth and the emissions of mercury from tissues.

EmissionsHgc = Emissions_teethHgc + Emissions_tissueHgc	(H10)

Where:

EmissionsHg,c	= Emissions of mercury from human cremation in county c, in pounds

Emissions_teethHg,c = Emissions of mercury in teeth from human cremation in county c, in pounds
Emissions_tissueHg,c= Emissions of mercury in tissues from human cremation in county c, in
pounds

Animal Cremation

Emissionsp c = Cremation_tonsc x EFp	(A5)

Where:

Emissionsp c = Emissions of pollutant p from animal cremation in county c, in pounds

Cremations_tonsc= The number of animal cremations in county c, in tons

EFP	= Emissions factor for pollutant p from animal cremation, in lbs. per ton

29.2.6 Sample calculations

Table 29-5 lists the sample calculations for estimating mercury emissions from human cremation in the
85+ age group and animal cremation of cats in Clark County, ID. To estimate the total emissions in Clark
County, these steps would be repeated to estimate emissions from all age groups and from cremation of
dogs.

29-6


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Table 29-5: Sample calculations for mercury emissions from human cremation for the 85+ age group and
	cremation of cats in Clark County, ID	

Eq.

#

Equation

Values for Clark County, ID

Result

HI

Deaths_withheldsa
= Deaths_statesa

— ^ Deaths_countysa

4,013 state level deaths

— 3,997 total county level deaths

16

withheld
deaths in
Idaho

H2

P0Vr

873 people in Clark County

0.442

population

ratio

i <~>yratior

C POPs

1,975 total population of counties with withheld deaths

H3

Deathsca

Deathswithheidsa
x Poprafi0c

16 withheld deaths x 0.442 population ratio

7 deaths in
Clark

County, ID

H4

Cremationsc a
= Deathsca
x Cremationrate

7 deaths x 56.8% cremationrate

4

cremations
in Clark
County, ID

H5

Cremations _tonsc

A

= ^ Cremationsc a x Wa

a = 1

1 ton
X 2,000 lbs

4 cremations x 158.25 lbs per person in
85 + age group h- 2000 lbs per ton

0.3165
tons

cremations
in Clark
County, ID

H6

EF_teeth^g a

= Materiala x ContainHga
x HgProportion
lb

x 0.0022 —

9

2.96 g mercury x 75 % with mercury x
45% of fillings are mercury x 0.0022

0.0022 lbs.

mercury

per

cremation

H7

Emissionspc
= Cremationtons x EFp

N/A

Completed
in equation
H9 for
mercury

H8

Emissionstgetft c
A

= ^ Cremationsc a

a = 1

x EFteethHg a

4 cremations x 0.0022 lbs per cremation

0.0088 lbs.
mercury
from teeth
in 85+ age
group in
Clark

County, ID

29-7


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Eq.

#

Equation

Values for Clark County, ID

Result

H9

Emissionstissue Hgc
= Cremationstons

^ EFtissue ffg

0.3165 tons cremations x 0.0015 lbs per ton

0.00047
lbs.

mercury
from
tissues in
85+ age
group in
Clark

County, ID

H10

EmissionsHg c

EYniSSiOTlStegtft c
-(- Emissions^issue ^g c

0.0088 lbs from teeth + 0,00047 lbs. from tissues

0.0093 lbs.

mercury

from

cremation
of 85+ age
group in
Clark
County ID

A1

Cremationsc/dus
= Ratioc/d

x (Cremations_petsus
+ Cremations _shelterus)

52.5% of cats in pet population

x (1,840,965 pet cremations
+ 2,700,000 shelter animal cremations)

2,384,006
cremated
cats in the
U.S.

A2

Cremationstons c

d

= Cremationsc x Weightc
d d

1 ton

X	

2,000 pounds

2,384,006 cremated cats x 9.9 lbs per cat
h- 2000 lbs per ton

11,800
tons of
cremated
cats in the
U.S.

A3

Cremations tmiq ,

iunb animal

= Cremationstons
+ Cremationstons d

N/A

Cremations
of dogs are
not

estimated
in this
sample
calculation

A4

Cremations_tonsanimal c
Cremations _tonsanimaius

Popr
x	—

Popus

873 people in Clark

11,800 cremated cats x			

329,164,967 people in US

0.03 tons
cats

cremated
in Clark
County, ID

29-8


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Eq.

#

Equation

Values for Clark County, ID

Result







0.000045







lbs.







mercury

A5

Emissionspc
= Cremationtons x EFp

0.03 x 0.0015 lbs per ton

emissions
from

cremation
of cats in
Clark

County, ID

29.2.7	Improvements/Changes in the 2020 NEI

There are no significant changes from the methodology used to calculate the 2020 NEI emissions.

29.2.8	Puerto Rico and U.S. Virgin Islands

Since insufficient data exists to calculate emissions from human cremation for the counties in Puerto
Rico and the US Virgin Islands, emissions are based on two proxy counties in Florida: 12011, Broward
County for Puerto Rico and 12087, Monroe County for the US Virgin Islands. The total emissions in tons
for these two Florida counties are divided by their respective populations creating a tons per capita
emissions factor. For each Puerto Rico and US Virgin Island county, the tons per capita emissions factor
is multiplied by the county population (from the same year as the inventory's activity data) which served
as the activity data. In these cases, the throughput (activity data) unit and the emissions denominator
unit are "EACH".

Emissions from animal cremation are based on county population; therefore, the emissions from animal
cremation in Puerto Rico and the Virgin Islands are calculated using the method described for the rest of
the counties.

29.3 References

1.	CDC. 2017 WONDER Database. Table 2, last accessed March 2019.

2.	National Funeral Directors Association (NFDA). 2020. The NFDA Cremation arid Burial Report:
Research, Statistics and Projections, last accessed December 2021.

3.	CDC 2016. Anthropometric Reference Data for Children and Adults: United States, 2011-2014.
Vital Health Statistics, Series 3, Number 29, last accessed August 2018.

4.	Pet Loss Professionals Alliance (PLPA). 2013. Pet Loss Professionals Alliance Releases Finding of
Inaugural Professional Survey, last accessed August 2018.

5.	Humane Society of the United States. 2014. Pets by the Numbers, last accessed August 2018.

6.	Mattern, M.Y. and D.A. McLennan. 2000. Phylogeny and Speciation of Felids. Cladistics, 16: 232-
253.

7.	Modern Puppies. Breed Weight Chart, last accessed August 2018.

8.	U.S. Environmental Protection Agency. 1993. AP-42: Compilation of Air Emissions Factors, Fifth
Edition, Volume I, Chapter 2.3 - Medical Waste Incineration, Tables 2.3-2 and 2.3-15.

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9.	U.S. Environmental Protection Agency. 1999. Emission Test Evaluation of a Crematory at
Woodlawn Cemetery in the Bronx, NY, Vol. I-III, EPA-454/R-99-049.

10.	California Air Resources Board. 1999. Development of Toxic Emissions Factors from Source Test
Data Collected Under the Air Toxics Hot Spots Program, Part II, Volume I. Prepared by GE Energy
and Environmental Research Corporation.

11.	Reindl, J. 2012. Summary of References on Mercury Emissions from Crematoria, last accessed
August 2018.

12.	Lundquist, J.H. 2012. Mercury Emissions from the Cremation of Human Remains. Bay Area Air
Quality Management District.

13.	Food and Drug Administration. 2017. About Dental Amalgam Fillings, last accessed August 2018.

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United States	Office of Air Quality Planning and Standards	Publication No. EPA-454/R-23-001cc

Environmental Protection	Air Quality Assessment Division	March 2023

Agency	Research Triangle Park, NC


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