U. S. ENVIRONMENTAL PROTECTION AGENCY Washington, D.C. 20460

OFFICE OF

CHEMICAL SAFETY AND

POLLUTION PREVENTION Date: April25, 2012
Chemical: Sodium Diacetate

PC Code: 044008

### ~c_,~li)f\ -U:I-l 516'-1'1

DP Barcode: D391552

MEMORANDUM

SUBJECT: Registration Review

- Qualitative Ecological Risk Assessment and Effects
Determination of Sodium Diacetate

TO:

FROM:

THROUGH: Melanie Biscoe, Chemical Review Manager

Anne Overstreet, Risk Manager
Pesticide Re-evaluation Division (7508P)



## ·**~;tr;** l-f! ?- 

## s- /1 ')____ Meghan Radtke, Ph:D.,

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. _ . HeZhong,Ph.D.,Bwlog1st ·

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# 4/-:v:r; 2/11/..-z..--
Environmental Risk Branch I
Environmental Fate and Effects Division (7507P)

## £v;bl,~**Na~cy** Andrews, Ph.D.,

### Branch.Chie~**~ ~**  { ,v

### (~-- •

### ~ Sujatha Sankula, Ph.D., Lead Bwlog1st

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= ;..=---·· Environmental Risk Branch I
Environmental Fate and Effects Division (7507P)

The Environmental Fate and Effects Division (EFED) has conducted a qualitative evaluation of
sodium diacetate as a part of the registration review process and concluded that the use of this compound, based on the label directions, should not pose an unreasonable risk to non-target organisms. Sodium diacetate is a sodium acid salt of acetic acid, which readily dissociates into
acetic acid and sodium acetate. It is applied to hay (stored in bales) to prevent spoilage, to silage

as an aid in fermentation, and to preserve the quality of animal feeds such as field com, alfalfa, sorghum, oats, and grasses that are stored in silos. It is also registered for use as a supplement to livestock/poultry feeds and dairy rations. Consequently, EFED concludes a "No Effect"
determination for all currently registered uses of sodium diacetate for all non-target organisms.

1 

# 1111111111
20872451 U. S. ENVIRONMENTAL PROTECTION AGENCY

Washington, D.C. 20460

OFFICE OF
CHEMICAL SAFETY AND
POLLUTION PREVENTION Date: April 25

, 2012
Chemical: Sodium Diacetate
PC Code: 044008
DP Barcode : D391552

MEMORANDUM

SUBJECT: Registration Review

– Qualitative Ecological Risk Assessment and Effects

Determination of Sodium Diacetate

TO: Melanie Biscoe, Chemical Review Manager

Anne Overstreet , Risk Manager
Pesticide Re

- evaluation Division (7508P)

FROM : Meghan Radtke, Ph.D., Biologist

He Zhong

, Ph.D., Biologist
Environmental Risk Branch I Environmental Fate and Effects Division (7507P)

THROUGH : Nancy Andrews, Ph.D., Branch Chief

Sujatha Sankula, Ph.D., Lead Biologist
Environmental Risk Branch I Environmental Fate and Effects Division (7507P)

The Environmental Fate and Effects Division ( EFED ) has conducted a qualitative evaluation of
sodium d iacetate as a part of the registration review process and concluded that the use of this compound, based on the label directions, should not pose an unreasonable risk to non

- target organisms. Sodium diacetate is a sodium acid salt of acetic acid, which re adily dissociates into acetic acid and sodium acetate. It is applied to hay (stored in bales) to prevent spoilage, to silage as an aid in fermentation, and to preserve the quality of animal feeds such as field corn, alfalfa, sorghum, oats, and grasses tha t are stored in silos. It is also registered for use as a supplement to livestock/poultry feeds and dairy rations. Consequently, EFED concludes a “No Effect” determination for all currently registered uses of sodium diacetate for all non

- target organisms

.2 

## REGISTRATION REVIEW

ECOLOGICAL RISK ASSESSMENT AND EFFECTS

DETERMINATION

Sodium Diacetate

CAS Number: 126

- 96

- 5

USEPA PC Code: 044008

PREPARED BY: Meghan Radtke, Ph.D., Biologist He Zhong, Ph.D.

, Biologist

, Environmental Risk Branch 1
Environmental Fate and Effects Division

PEER REVIEW TEAM: Faruque Khan, Ph.D., Senior Scientist Sujatha Sankula, Ph.D., Lead Biologist

APPROVED BY: Nancy Andrews, Ph.D., Branch Chief
Environmental Risk Branch 1
Environmental Fate and Effects Div ision Office of Pesticide Programs3 

### Table of Contents

List of abbreviated terms and symbols 4 Executive summary 6
Nature of stressor 6
Use information 6
Ph ysical and chemical properties 6 Ecotoxicity data 8 Ecological risk conclusions 9
Introduction 11 Purpose of assessment 11
Problem formulation 12 Nature of regulatory action 12
Previous assessments 12 Stressor description 13
Use characterizati on and methods of application 14
Modi fication to registered labels 17 Ecosystems potentially at risk 17
Risk hypothesis 18 Analysis plan 18
Su mmary of environmental fate 19 Effects to organi sms 20 Aquatic effects 20

F ish and aquatic invertebrates 20 Aquatic plants 22
Terrestrial effects 23 Birds, reptil es, and land

- phase amphibians 23
Mammals 23
Terrestrial inver tebrates 24 Terrestrial plants 24
Incident database review 25
Risk to non

- listed and listed species 25
Indir ect effects to listed species 26
Effects to critical habitat 26 Bibliography 28 ECOTOX papers 30 Appendix A 414 

### List of Abbreviated Terms and Symbols

% symbol for “percent”

> symbol for “greater than”

o C symbol for “degrees Celsius”
ai active ingredient
bw body weight
CI c onfidence interval

D P Data Package
EC 50 50 % (or median) effect concentration

EFED Environmental Fate and Effects Division

e.g. Latin exempli gratica (“for example”)
et al. Latin et alii (“and others”)

etc. Latin et cetera (“and the rest” or “and so forth”)

FIFRA Fe deral Insecticide Fungicide and Rodenticide Act FQPA Food Quality Protection Act

i.e. Latin id est (“that is”) kg kilogram(s)

K oc symbol for the organic carbon partitioning coefficient

LAA likely to adversely affect
l b ai/A pound(s) of active ingredient per acre
IC 50 50% (or median) inhibition concentration
LC 50 50% (or median) lethal concentration

LD 50 50% (or median) lethal dose
LOC level of concern MA may affect

m g milligram(s) mg/kg m illigrams per kilogram (equivalent to ppm) mg/L milligrams per liter (equivalent to ppm)

MRID master record identification number
NASS National Agricultural Statistics Service NAWQA National Water Quality Assessment

NE no effect
NLAA not likely to adversely affect
NMFS National Marine Fisheries Service
NOAA National Oceanic and Atmospheric Administration
NOAEC n o observable adverse effect concentration
NOAEL no observable adverse effect level
OPP Office of Pesticide Programs
OPPTS Office of Prevention, Pesticides, and Toxic Substances5

pH symbol for the negative logarithm of the hydro gen ion activity in an aqueous solution,

dimensionless pKa symbol for the negative logarithm of the acid dissociation constant, dimensionless

ppm parts per million (equivalent to mg/L or mg/kg)
USDA United States De partment of Agriculture
USEPA United States Environmental Protection Agency
USFWS United States Fish and Wildlife Service

W t weight6



### Executive Summary

Nature of Stressor

The Agency has conducted a qualitative evaluation of sodium diacetate as a part of the registration review process and concluded that the use of this compound

, based on the label
direction s, should not pose an unreasonable risk to non

- target organisms

. Sodium diacetate is a
sodium acid salt of acetic acid , which r eadily dissociate s in to acetic acid and s odium acetate.

A cetic acid is the active moiety of sodium diacetate

, which acts as fungicide and bactericide to control molds and bacteria by temporarily changing the local acidity. Acetic acid is a l so a naturally occurring chemical in plants and animals and an integral part of the Kreb’s cycle, forming adenosine

- 5

- triphosphate ( ATP ) for energy. It is applied to hay (stored in bales) to prevent spoilage

, to silage as an aid in fermentation

, and to preserve the qual ity of animal feeds such as field corn, alfalfa, sorghum, oats, and grasses that are stored in silos. It is also registered for use as a supplement to livestock/poultry feeds and dairy rations.

Application rates of sodium diacetate for hay and grain pr eservation are dependent upon the moisture content of the grains at the time of storage; application rates are 2 to 3 lb ai/ton of feed/hay. A pplication is usually not recommended at moisture contents above 25 % (hay), 35% (high moisture ensiled corn) and 70% (silage)

. For dairy rations, the maximum application rate
is 2 lb ai/ton.

Use Information
Sodium diacetate is applied to crops post harvest. For baled hay preservation, application occurs at the time of baling in the field. Bales are then either s tored outside

, covered in plastic, or moved to sheds until needed. As a feed supplement for poultry, livestock, and dairy rations, sodium diacetate is added directly to the feed, either during the grinder/mixer stage or as a top dressing (dairy rations on ly). La stly, sodium diacetate can be us ed for the preservation of processed corn, hay, sorghum, oat, and grass silages that are to be stored in a conventional upright, oxygen limiting pit and bunker silo. These applications occur at the time of chopping or at the blower when the silage is being loaded into the silo.

Physical and Chemical Properties
Sodium diacetate (CH 3 COONaCH 3 COOH) is described as a 1:1 mixture of sodium acetate and
acetic acid

, and is stable at ambient temperature. It is a white, hygro scopic , crystalline solid having an odor of acetic acid. The pH in a 10% (w/v) solution is 4.5

- 5.0 and gives positive tests
for a cetate and sodium

. The molecular weight is 143.1 g/mole and t he melting point is 150

. 5 5 o C (Table 1 )

. It is readily soluble in water (1g/ml) , slightly soluble in alcohol

, and insoluble in ether (USEPA 1991). One gram of sodium diacetate is soluble in about 1 ml of water, liberating its major degradate s

– acetic acid (CH 3 COOH) and sodium acetate (CH 3 COONa)

. A cetic acid is7

also registered as a non

- selective herbicide for control of broadleaf weeds and weed grasses to residential, golf courses, non

- crop, right of way and industrial land sites (USEPA 2008).

Acetic acid is a naturally occurring compound in plants and animals with a fundamental role in cell metabolism, particularly in the tricarboxylic cycle (Kreb’s cycle). A t 25 o C, the solubility of
acetic acid is 1.00E

- 06, the vapor pressure is 15.7 mm Hg, the Henry’s Law Constant is 1.00E

07 atm

- m 3 /mole and the pKa dissociation constant is 4.76 (TOXNET ) (Table 1)

. As acetic acid enters the tricarboxylic cycle, the acetyl molecule is broken down and serves as a source of energy transformed into ATP. In contrast, the a nabolic production of fatty acids in plants and animals also involves the incorporation of two carbon acetyl molecules; however, when acetic acid is sprayed on terrestrial plants, it disrupt s the integrity of the cell membrane and results in leakage of cel lular fluids

, causing the plant to dry out. Acetic acid has toxic effects on the central nervous system and kidneys (Clayton and Clayton 1982 ). A cetic acid is a weak acid and capable of affecting local pH.

T he by

- products from environmental degradation of acetic acid are depende nt on redox potential (Lindsay 1979 ). The estimated half

- li v es of ac e tic acid are about 17.3 days in soil and 8.7 days in water (EPI Suite 4.1). In oxic and suboxic environments, CO(g), HCOO

- , and C 2 O 4
- are transient degradation products with eventual formation to CO 2

. E thane (C 2 H 4 ) formation occur s only at extremely low redox conditions. Under anoxic conditions, methane is produced from
acetic acid. Another major degradate , sodium acetate, produces sodium cations and acetate
anions. The sodium cations may combine with other reactive materials in the soil. Below a re the two main reactions for acetic acid /acetate anion degradation :

Aerobic/Suboxic Conditions: CH 3 COO

- + 2H 2 O

-------- 2 CO 2 + 8e

- + 7H+ log K o =

- 9.64 Anaerobic Condition : CH 3 COO

- +8e

- +9H+

--------------- 2CH 4 (g) + 2H 2 O log K o = 36.19

Table 1

. Physical and Chemical Properties of Sodium Diacetate and Acetic Acid (Major Degradation Product).

Parameter Value Reference

Sodium Diacetate (Parent)

Chemical Name Sodium Diacetate MRID 2058971
CAS Number 126

- 96

- 5 TOXNET
Molecular Formula CH 3 COONaCH 3 COOH MRID 2058971 Molecular Weight 143.1 g/mole TOXNET
SMILES Code C(O)(=O)C.C(C)(=O)[O

- ].[Na+] TOXNET Melting Point ( o C) 1 50.55 EPI Suite (v 4.10) Boiling Point ( o C) 424.96 EPI Suite (v 4.10) Vapor pressure (25°C) 1

. 08 x 10

- 7 mm Hg @ 25 o C EPI Suite (v 4.10) Henry’s Constant 9.27 x 10

- 9 atm m 3 mole

- 1 EPI Suite (v 4.10) Solubility ( 2 5 o C) 1 k g/ L MRID 2058971

K oc 1 ml/g (mean) EPI Suite (v 4.10)8 Parameter Value Reference

Acetic Acid (Major degradate)

Chemical Name Acetic Acid MRID 2058971
CAS Number 64

- 19

- 7 TOXNET
Molecular formula C 2 H 4 O 2 EPI Suite (v 4.10) Molecular weight 60.5 g/mol EPI Suite (v 4.10)
SMILES Code O=C(O)C EPI Suite (v 4.10) Melting Point ( o C) 16.6 TOXNET Boiling Point ( o C) 117.9 TOXNET Vapor pressure (20/25°C) 15.7 mm Hg @ 25 o C TOXNET Henry’s Law Constant 1.0 x 10

- 7 TOXNET Solubility (2 5 o C) 1.0 x 10 6 mg/L TOXNET

K oc 1 ml/g (mean) EPI Suite (v 4.10)

Ecotoxicity Data
One registrant

- submitted study is a vailable for sodium diacetate. A rat acute oral toxicity study
demonstrated an LD 50 of 5600 mg ai/kg, classifying the chemical as practically non

- toxic to
mammals . A n open literature search did not yield any additional data specifically for sodium
diacetate.

Several regist rant

- submitted and open literature studies are available for sodium diacetate degradates

– acetic acid and sodium acetate

. These studies present a relatively benign picture of
the two degradates . Acute data for freshwater fish (MRID 48770801 ) , freshwater mollusks (Cairns et al. 1976 )

, estuarine/marine fish (Locke et al. 2009 )

, and estuarine/marine invertebrates (Locke et al. 2009 ) all classify acetic acid as slightly toxic to practically non

- toxic. Acetic acid is classified as slightly toxic to freshwater oligochaete worms (MRID 48770801 ) and f reshwater invertebrates (MRID 48770802 ) . For terrestrial insects, an acute exposur e of 26

, 225 mg ai/hive showed no mortality in honey bees nor the varroa mites inhabiting the hive (van Engelsdorp et al. 2008) . Toxicity data for freshwater vascular plants, non

- target algae, and freshwater diatoms
are IC 50 = 549 mg ai/L, 4000 mg ai/L, an d 74 mg ai/L, respectively. No t oxicity stud ies w ere available for terrestrial plants , although Stopar ( 2008 ) reported necrosis and chlorosis o n apple leaves that were exposed to acetic acid. This aligns with acetic acid’s registration as a non

selective herbicide ( USEPA 2010

, DP 367372).

Chronic exposure to sodium diacetate and its degradates is not expected, based on the s hort half

life of ace tic acid

.

When the Reregistration Eligibility Document for sodium diacetate was published in 1991, it was determined that there was sufficient knowledge to conclude that sodium diacetate was “ slightly
toxic to practically non

- toxic

, ” and a regulatory de cision was made that no further studies were
needed.9

Ecological Risk Conclusions Potential risks are expected to be minimal from the registered uses of sodium diacetate. For treatments that occur on the field, the risk of toxicological exposure to non

- ta rget plants and aquatic organisms from runoff is low. Very high concentrations of acetic acid (major degradate) would be necessary to change the pH of an aquatic system and thus cause toxic responses; this response is not expected from the labeled applica tion rate. In addition, acetic acid is practically

non

- toxic to freshwater fish, estuarine/marine fish, estuarine/marine invertebrates, vascular plants, and non

- vascular plants (USEPA 2010). Incidental acute exposure to terrestrial wildlife
that use the outdoor

- stored, non

- covered bales of hay as a resource ( e.g., food, shelter) is also low, given the short half life (the half life of acetic acid is approximately 17.3 days in soil and 8.7 days in water ). Sodium diacetate is practically non

- toxic to birds and mammals; acetic acid is practically non

- toxic to terrestrial insects and birds. For the feed fermentation and dairy ration uses, applications usually occur indoors or directly at the site of the silo. All treated fe ed that is used for livestock and poultry has the potential to be placed in the troughs of outdoor feedlots, but given the domestic surroundings ( e.g., farm buildings, farm houses, animal houses) , it is unlikely to come into contact with many non

- target sp ecies ; listed species are unlikely to frequent such built up areas

. In short, e ven if an incidental exposure of sodium diacetate or
acetic acid occurs through terres trial or aquatic pathways

, the potential effects are expected to b e short lived, localized

, and not likely to cause any adverse effects.

The following table lists the potential direct and indirect effects to listed species from use of sodium diacetate on grain/hay storage and feed (Table 2 )

.10

Table 2

. Potential risks to non

- listed and listed s pecies associated with direct or indirect effects from the proposed application of sodium diacetate

Taxonomic Group Effects Endpoint 1 Direct Effects 2 Indirect Effects to Listed Species
Non

Listed Listed Potential Indirect Effects from Direct Effect to: 3 Aquatic vascular plants Measures of biomass No No No Not applicable

Aquatic non

vascular plants Measures of biomass No No No Not applicable

Terrestrial plants Measures of biomass

- NA 4 No No No Not applicable
Freshwater vertebrates Acute: mortality

Chronic: NOAEC growth & reproduction

- NA No No No Not applicable

Estuarine/marine vertebrates Acute: mortality

Chronic: NOAEC growth & reproduction

- NA No No No Not applicable

Freshwater invertebrates Acute: mortality

Chronic: NOAEC growth & reproduction

- NA No No No Not applicable

Estuarine/marine invertebrates Acute: mortality

Chronic: NOAEC growth & reproduction

- NA No No No Not applicable

Mammals Acute oral dose: mortality

Sub

- acute dietary: mortality and growth

- NA Chronic: growth and reproduction

- NA No No No Not applicable

Birds Acute oral dose: mortality

NA Sub

- acute dietary: mortality and growth Chronic: growth and reproduction

- NA No No No Not applicable

Terrestrial invertebrates Acute contact and oral:

mortality No No No Not applicable

1 Abbreviations: NA = toxicity data not available

2 Negligible exposures to non

- target organisms from sodium diacetate registered uses being indoors or contained (no spray drift, runoff, spillage). Therefore, adverse effects are not expected.

3 Direct effects to species may result in indirect effects to other species by changing availability of prey, habitat, and other factors important to survival and reproduction.

4 Acetic acid is registered as a n on

- selective herbicide, so it is expected that if directly applied to

non

- target plants, there could be adverse effects; however, the usage on hay/silage/feed is not expected to come into contact with non

- target plants.11

Therefore, a “no effect” determination has been concluded for federally listed species for the registered uses of sodium diacetate on the preservation of hay, silage, and as a food supplement for livestock, poultry, and dairy co ws.



### Introduction

Purpose o f Assessment

The purpose of this assessment is to evaluate the potential risk to populations of non

- listed ( i.e.,

no t federally endangered or threatened) species, and endangered and threatened (listed) species from exposure to sodium diacetate and its deg radates from its registered use s . Risks from direct
and indirect effects are derived and evaluated in accordance with the risk assessment methodology described in the Agency’s Overview Document (USEPA, 2004). These risk findings are then used as part of an “effects determination” for listed species. The Agency will reach one of the following three conclusions regarding the potential for the registered sodium
diacetate use on non

- food crops to affect federally listed species:

 “No effect ;”

 “May affect, bu t not likely to adversely affect;” or

 “May affect, and likely to adversely affect.”

If the results of the risk assessment show no indirect effects and the levels of concern (LOCs) are

not ex ceeded for direct effects for the taxonomic grouping of a listed species ( e.g., freshwater fish, small herbivorous mammal), a “no effect” (NE) determination is made, based on sodium diacetate’s use within the action area for that species. If, however, there is a potential for indirect effects and/or risk quotients exce ed the listed species LOC values for direct effects for a given group, the Agency concludes a preliminary “may affect species” (MA) within the taxonomic group. The Agency then considers additional lines of evidence such as the geographical nature of the exposure, as well as more in

- depth evaluations of the toxicological and ecological requirements to determine a rationale for a “not likely to adversely affect” (NLAA) or “likely to adversely affect” (LAA) determination.

Similarly, the Agency will reach one of the following conclusions regarding the potential for
sodium diacetate’s uses to result in destruction of adverse modification of critical habitat:

 “No adverse modification of critical h abitat;”

 “ May affect primary constituent e lements.”12

The Agency uses the risk assessment analysis for direct effects to categories of biological resource requirements to draw conclusions about eff ects to primary constituent elements of critical habitat. The Agency is limited in a practical sense to those primary constituent elements of critical habitat that are of a biological nature. If the results of the risk assessment show that no
LOC is exce eded for all taxonomic groups, a “no effect” (NE) determination for habitat modification is made. If an LOC is exceeded for one or more taxonomic groupings, the Agency then considers additional lines of evidence to determine the rationale for a “may affec t primary constituent elements.” This evidence may include: the type and degree of effect on the taxonomic groups, expected resultant effects on biologically mediated environmental processes ( e.g., increased sedimentation from loss of vegetation) as comp ared to baseline environmental conditions, co

- occurrence of the action area with critical habitat, or the type of principle constituent elements associated with critical habitat for listed species in a taxonomic grouping.

A qualitative versus quantitative risk assessment for sodium diacetate was chosen based on two premises: 1) the “generally regarded as safe

– GRAS” food safety designation as assigned by the Food and Drug Administration (21 CFR 184.1005); and 2) the absen ce of sodium diacetate toxicity data.



### Problem Formulation

Nature of Regulatory Action

Under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA), all pesticides distributed or sold in the United States generally must be registered by the Unite d States Environmental Protection Agency (USEPA). To determine whether a pestic ide can be registered, the US EPA evaluates its safety to non

- target species based on a wide range of environmental and health effects studies. In 1996, FIFRA was amended by th e Food Quality Protection Act (FQPA), and EPA was mandated to implement a new program for the periodic review of pesticides

– registration review 1 . The registration review program is intended to ensure that, as the ability to assess risk evolves and as po licies and practices change, all registered pesticides continue to meet the statutory standard of no unreasonable adverse effects to human health and the environment. Changes in science, public policy, and pesticide use practices will occur over time.
Th rough the new registration review program, the Agency periodically reevaluates pesticides to make sure that as change occurs, products in the marketplace can be used safely.

Previous Assessments Sodium diacetate was assessed previously in the Reregistrati on Eligibility Document ( USEPA 1991). This document determined that the g eneral knowledge of sodium diacetate’s use pattern and chemistry were sufficient to make environmental assessments. More specifically, the

1 http://www.epa.gov/oppsrrd1/registration_review/13

document highlighted that sodium diacetate is applied to post

- harvest livestock feed crops that are primarily within farm facilities with limited environmental exposure. Exposure to aquatic environments from runoff events, if they occur, will only result in a short

- term change to the pH
that will be counteracted by the natural buffering capacity of the water. A 10 percent acetic acid
solution would be needed to change the pH to 4.5 from 5.0, which is unlikely, given the use
pattern. Sodium diacetate is the conjugate base of a weak acid, thus it is expected that the pH would remain relatively constant in a buffer solution of sodium acetate and acetic acid. Furthermore, sodium diacetate and its degradates are known to have low toxicity and are part of
th e normal function in metabolic pathways of animals (FASEB 1977) . Thus, the risk to wildlife
is deemed low.

Acetic acid, a major degradate, was assessed by the Biopesticide and Pollution Prevention Division (BPPD) (USEPA 2010, D367372) in 2010 . Two produ cts were considered

– an 8 percent acetic acid solution and a 20 percent acetic acid solution. The assessment indicated possible risk to birds, insects, and terrestrial plants at an application rate of 29.4 lb ai/A, four applications per season

.

No oth er risk assessments were identified.

Stressor Description
Sodium diacetate is a sodium acid salt of acetic acid, which readily dissociate s in to acetic acid
and sodium acetate in the presence of moisture. Acetic acid is the active moiety of sodium
diaceta te

, which acts as a fungicide and a bactericide to control molds and bacteria by temporarily changing the local acidity. It dissociates into acetate, sodium, and hydrogen ions. The ions that are produced by the dissociation of the sodium diacetate molecu le are normal components of plants, animals, and hu man foods.

Acetates are common metabolic intermediates in living organisms and are formed during the

met abolism of food substances. In particular, acetic acid is an integral part of the tricarboxylic

a cid cycle (Kreb’s cycle) and forms ATP for energy use in cells. Ac etates and acetic acid have long been used safely without major adverse effects in both human and animal foods at moderate levels of consumption (FASEB 1997). The Food and Drug Administrat ion lists acetic acid as a substance that is “generally recognized as safe” (GRAS) for use in food (21 CFR 184.1005)

. Acetic acid is commonly used for curing and pickling, flavoring, pH control, as a solvent
veh icle, and boiler water additive. It is used in concentrations of up to 9% in relishes and
condiments.

There are only two active registrations for sodium diacetate

– Crop Cure and Crop Cure 2

– both registered by Domain, Inc . for post

- harvest use on hay and silage (Table 3 )

. It is applied to hay (stored in bales) to prevent spoilage, to silage as an aid in fermentation, and to preserve the14

quality of animal feeds such as field corn, alfalfa, sorghum, oats, and grasses that are stored in silos. It is also registered for use as a supplement to livestock/poultry feeds and dairy rations. Acetic acid is registered as an herbicide (e.g., registration numbers 8655

- 11, 69836

- 1, 81936

- 1) and is being assessed separately by the Biopesticides and Pollution Prevention Division (BPPD).

T here are no active registrations for sodium acetate.

Use Characteristics and Methods of Application

Sodium diacetate is used for the preservation of baled hay (alfalfa, brome grass, clover, orchard grass, and timothy) that is to be stored for animal feed . Sodium diacetate prevents the spoilage of baled hay by inhibiting the growth of mold and microbes

. It is also an aid for silage fermentation (processed corn, hay, sorghum, oat, and grass silages) and an additive to improve the palatability of livestock feeds. Treated silage may only be fed to livestock and poultry.

Sodium diacetate can be applied in either a liquid or solid form. For hay preservation, solid

- form sodium diacetate is applied to uniformly cover the hay during the baling process using a Gandy applicator (mechanism for evenly applying granules to hay or other commodities) . For liquid applications, the sodium diacetate is diluted with water where it dissociates to form acetic acid. It should be uniformly applied at the time of baling us ing a pumping system with corrosion resistant parts. Application rates of sodium diacetate are de p endent on hay moisture content; sodium diacetate should only be applied to hay with 15 to 25 percent moisture content.

As a livestock and poultry feed additive, sodium diacetate is mixed into the feed using a grinder/mixer. To achieve the appropriate mixture, grains (corn, soybean, wheat, barley, oats, etc.) and other dry ingredients (pre

- mix diet supplements, vitamins, m inerals, etc.) are first mixed together followed by the appropriate amount of sodium diacetate. After mixing well, high moisture ingredients (liquid vitamins, molasses, etc.) are incorporated; insufficient mixing may produce inconsistent mold inhibition. Sodium diacetate application rates are dependent upon the moisture content of the feed and should be applied to feeds containing 15 to 30 percent moisture.

As an aid in silage fermentation, sodium di acetate can be applied either as a solid or a liquid. For solid applications, a Gandy applicator (or equivalent) should be used to apply sodium
diacetate at t he time of chopping or at the b l o wer when the silage is being loaded into the silo. The timing for liquid applications is the same, but a liquid applic ator should be used. Application rates of sodium diacetate are dependent on silage moisture content (Tables 4 and 5 )

. For corn, hay, grass, oat, and sorghum silage, the moisture content should be 50 to 70 percent; for high moisture ensiled corn, the mo isture content should be 25 to 35 percent.

As an additive to dairy rations, sodium diacetate can be mixed into the feed or offer ed as a top dressing . When mixed into the feed, sodium diacetate is added after the other dry ingredients,15

but before the high moisture ingredients. When applied as a top dressing, it is sprinkled over the feed shortly before offering to livestock.

Table 3 . Current sodium diacetate r egistrations Registration Name (Registration Number) Company Active Ingredient Uses

Crop Cu re (32240

- 2) Domain, Inc. 50% Preservation of baled hay (alfalfa, brome grass, clover, orchard grass, and timothy) to be stored for the feeding

season Crop Cure 2 (32240

- 6) Domain, Inc. 80% For the preservation of bal ed hay (alfalfa, brome grass, clover, orchard grass, and Timothy) to be stored for the feeding season ; improvement of palatability in livestock feeds (beef, swine, poultry , dairy cows ) ; and aid in silage (processed corn, hay, sorghum, oat, and grass) fermentation

Table 4

. Listing of label uses, application rates, form and equipment for sodium diacetate

Use Site Max. Rate per

Application (Registration Number) Number of

Applications Form Application Equipment/Type

Hay

– alfalfa, brome grass, clover, orchard grass, and timothy 2 lb ai /ton of hay

(liquid) (32240

- 6)

2.5 lb ai/ton of hay (solid) (32240

- 2) Single application Liquid or solid Pumping system

(liquid)

Gandy applicator (solid) Ground feeds

– corn soybean, wheat, barley, oats, etc. (beef, swine, and poultry feeds) 3 lb ai/ton of feed

(32240

- 2) Single application Solid Livestock feed mixer/grinder

Silage fermentation

– corn, hay, sorghum, oat, grass 3 lb ai/ton of silage

(32240

- 2) Single application Liquid or solid Liquid applicator

(liquid)

Gandy applicator (solid) Dairy ration

– corn, soybean, wheat, barley, oats, etc. 2 lb ai/ton of feed

(32240

- 2) Single application Solid Mix in feed or top dressing to feed16

The Biological and Economic Analysis Division (BEAD) did not have up

- to

- date usage
information (Screening Level Usage Estimates of Agricultural Uses

– SLUA) for sodium
diacetate. D etailed information about the uses was provided following a screening of the labels
in 2007. T he labels have not undergone any changes in 5 years and the information is still
relevant (Table 5 )

.

Table 5 . Label information for sodium diacetate

Use site Max. rate per

app. Feed type Form Application type

Alfalfa 0.125 0 lb/ cwt Terrestrial feed

crop Form not

identified/solid Soluble concentrate/solid Spray/stored

commodity non

fumigation

Clover 0.1250 lb/cwt Terrestrial feed

crop Form not

identified/solid Soluble concentrate/solid Spray/stored

commodity non

fumigation

Corn (processed/ground) 0.5000 gal/ton Indoor food Soluble concentrate/solid Stored

commodity non

fumigation 2 lb/ton Form not identified/solid Dairy animal feed (processed) 0.0156 lb/animal Indoor food Soluble concentrate/solid Top dressing
3 lb/ton Stored commodity non

fumigation
Grass forage/fodder/hay 0.0250 gal/cwt Terrestrial feed

crop Soluble

concentrate/solid S tored

commodity non

fumigation 0.1250 lb/cwt Form not identified/solid Soluble concentrate/solid Spray/stored

commodity non

fumigation

Hay (silage) 0.0250 gal/cwt Terrestrial feed

crop Soluble

concentrate/solid Stored

commodity non

fumigation 0.0500 lb/cwt Form not identified/solid Livestock feed (processed) 3 lb/ton Indoor food Soluble concentrate/solid Stored

commodity non

fumigation Oats (processed) 0.5000 gal/ton Indoor food Soluble concentrate/solid Stored

commodity non

fumigation 1 lb/ton Form not identified/solid Poultry feed (processed) 3 lb/ton Indoor food Soluble concentrate/solid Stored

commodity non

-17

Use site Max. rate per

app. Feed type Form Application type

fumigation Sorghum (unspecified) 0.0250 gal/cwt Terrestrial feed

crop Soluble

concentrate/solid Stored

commodity non

fumigation 0.0500 lb/cwt Indoor food Form not identified/solid Timothy 0.1250 lb/cwt Terrestrial feed

crop Form not

identified/solid Soluble concentrate/solid Spray/stored

commodity non

fumigation

Abbreviations: cwt = hundred weight

Modifications to Registered Labels There have been no substantial modifications to registered labels since the Problem Formul ation was written (USEPA 2008, DP 344770).

Ecosystems Potentially at Risk The registered uses of sodium diacetate are either indoor uses or outdoor uses that are isolated and relatively contained. For the feed fermentation and dairy ration uses, applications usually occur indoors or directly at the site of the silo. All treated feed that is used for livestock and

p oultry has the potential to be placed in the troughs of outdoor feedlots, but given the domestic surroundings ( e.g., farm buildings, farm house, animal houses) , it is unlikely to come into contact with many non

- target species ; listed species are unlikely t o venture into such developed areas

.

For baled hay treatments that occur on the field, the risk of exposure from runoff is low; very high concentrations of acetic acid (major degradate) would be necessary to change the pH of an aquatic system and thus c ause toxic responses. Incidental acute exposure to terrestrial wildlife using the bales of hay as a resource is also low, given the short half life (the estimated half

- life of
acetic acid is approximately 17.3 days in soil and 8.7 days in water ). In addi tion, the available toxicity data for sodium diacetate, sodium acetate, and acetic acid indicate that these chemicals are practically non

- toxic to mammals and slightly toxic to practically non

- toxic to aquatic species. Given that exposure is expected to b e negligible for both aquatic and terrestrial systems, it is not expected that the registered uses of sodium diacetate would pose any risk to threatened or endangered species.18

Risk Hypothesis

For sodium diacetate, the following ecological risk hypothesis is being tested :

 Based on a qualitative review of the available information indicating negligible exposure to the terrestrial and aquatic environment, sodium diacetate will not pose an adverse risk

to non

- target terrestrial and aquatic organism s.

Analysis Plan In Registration Review, pesticide ecological risk assessments will follow the Agency’s Guidelines for Ecological Risk Assessment and will be in compliance with the paper entitled, “Overview of the Ecological Risk Assessment Process in the Office of Pesticide Programs, U. S.
Environmental Protect ion Agency” (USEPA 2004).

The focus of an ecological risk assessment is on both the toxic effects of a pesticide to non

- target organisms and the potential routes of the pesticide’s exposure to non

- target organisms. In addition to addressing a pesticide’s toxic effects and potential routes of exposure, an ecological risk assessment addresses the uncertainties associated with a pesticide’s risk to non

- target organisms.

Consistent with the Agency’s responsibility under the Endangered Species Act (ESA), the Agency will evaluate risks to federally

- listed threatened and/or endangered (listed) species from registered uses of sodium diacetate. This assessment will be conducte d in accordance with the Overview Document (USEPA 2004), provisions of the ESA, and the Services’ Endangered Species Consultation Handbook (US FWS/NMFS 1998).

In the case of a nationwide risk assessment conducted under registration review, the action are a will encompass the entire U.S. and its territories. The purpose of defining the action areas as the entire U.S. and its territories is to ensure that the initial area of consideration encompasses all areas where the pesticide may be used now and in the future, including the potential for off

- site transport via spray drift and downstream dilution. Additionally, the concept of a nationwide action area takes into account the potential for direct and indirect effects and any potential
modification to critic al habitat based on measured ecological effect s that are associated with a reduction in survival, growth, and reproduction, as well as the full suite of sub

- lethal effects
available in the effects literature.

It is important to note that the nationwide ac tion area does not imply that direct and/or indirect effects and critical habitat modification are expected to or are likely to occur over the full extent of the action area, but rather to identify all listed species and critical habitat that may potential ly be affected by the action. The Agenc y will use more rigorous analyse s , including consideration19

of available land cover data, toxicity data, and exposure information

, to determine areas where individual listed species and designated critical habitat may be affected or modified via endpoints associated with reduced survival, growth, or reproduction.

Since exposure to non

- target organisms from sodium diacetate use is expected to be negligible, no aquatic or terrestrial ecosystem is expected to be potentia lly at risk from registered uses of sodium diacetate. Therefore, a quantitative risk assessment will not be performed, but rather risk to terrestrial and aquatic organisms will be qualitatively assessed , in which no estimated
environmental concentrations (EECs) or risk quotient (RQ) values will be generated

.

Summary of Environmental Fate

T he environmental fate of sodium diacetate and its two m ajor degradate s , acetic acid and sodium

acetate

, is well known. Environmental loadings are attributable to natural (plants and animal materials) and anthropogenic (food additives, drugs, and related products) sources. In water,

s odium diacetate dissociates into an acetic acid

- sodium acetate solution. The decompositio n of these two compounds is very well established in the chemical and biological literature. Acetic acid decomposes directly into CO 2 and water. A cetic acid combines with metallic ions derived from other compounds in the soil to form acetate salts such a s sodium acetate. In solution,

s odium acetate produces sodium cations and acetate anions. The sodium cations may combine
with other reactive materials in the soil. Acetate sorption is faster than its microbial uptake and utilization (Fisher and Kuzyakov 2010). The acetate anions will decompose to CO 2 and ethane.
CO 2 is a common constituent of the atmosphere while ethane is a minor constituent in the atmosphere in many areas. Anions of the compounds undergo aerobically mediated mineralization in days t o weeks

, and complete ly degrade in to CO 2 and water. A recent study shows, at a concentration of 10 μ mol /L , the acetate anion has a half

- life of about 3 minutes in
soil solution and the oxidation to CO 2 i s at a similar rate for the carbon atoms of both the

– CH 3 and

– COOH groups

. However, the decomposition to CO 2 for carbon from

– CH 3 decreased more strongly than carbon from

– COOH at acetate concentrations that were greater than 100 μ mol /L (Fisher and Kuzyakov 2010)

. Appendix A shows the complete degrad ation pathways of sodium
diacetate and its metabolites.

Mobility of sodium diacetate, acetic acid

, and sodium acetate is expected to be hig h

, based on adsorption estimates ( Koc = 1 ml/g, EPI 4.1). H owever, migration to ground water should be substantially mediated through biodegradation, volatilization, hydrolysis or through uptake and utilization within plant cells. Terrestrial organisms may be potentia l l y expose d to acetic acid vapor following a r ain event , as suggested by the high v apor pressure of acetic acid ( 15.7 mm Hg )

. W ith a pKa at 4.74, acetic acid will exist almost entirely in the ionized form at pH 5

– 9 and therefore, volatilization from the moist soil surfaces may not be an important f ate process (TOXNET). The toxicity of sodium diacetate and acetic acid is driven by the acetate anion with20

the cations playing a minor role. S odium diacetate and acetic acid are not persistent in the
environment based on the predicted value (Table 6).

Table 6

. Environmental fate of acetic a cid (major d egradat e )

Parameter Value Reference

Hydrolysis 8.7 days EPI Suite (v 4.10)
Aqueous Photolysis (t1/2) 17.2 days EPI Suite (v 4.10)
Aerobic Soil Metabolism (t1/2) 17.3 days EPI Suite (v 4.10)
Anaerobic Aquatic Metabolism (t1/2) 77.9 days EPI Suite (v 4.10)

Effects to Organisms

Few sodium diacetate toxicity studies are available for non

- target organisms. Given that the compound dissolve s in water to become acetic acid and sodium acetate

, EFED reviewed the
effects of these degradates to non

- target organisms. Data for sodium diacetate, sodium acetate,
and acetic acid indicate these substances to be slightly toxic to practically non

- toxic on an acute basis. Given that the exposure is expected to be negligible, it is unlikely that there would be any
adverse effects to non

- target organisms. The follow ing is the summary of EFED ’s review.

AQUATIC EFFECTS Aquatic exposure to sodium diacetate and its degradates is expected to be negligible. While sodium diacetate runoff may occur in the form of its degradate, acetic acid (formed via hydrolysis ) , it is unlikely that the weak acid will significantly alter the pH of an aquatic system or pose a potential hazard bec ause of its short half

- life (approximately 17.3 days in soil and 8.7 days in water ).

No sodium diacetate toxicity studies are available for aquatic organisms

, given that the compound dissociate s , instantaneously into an acetic acid and sodium acetate so lution ; h owever, several submitted and open literature studies on the degradates have provided information.

Fish and Aquatic Invertebrates

An acetic acid acute toxicity study on Daphnia magna reported a 48

- h EC 50 as 65 ± 9.0 mg ai/L, classifying acetic acid as slightly toxic to freshwater invertebrates (MRID 48770802 )

.

A second study examined the acute effects of acetic acid on several freshwater species: tilapia ( Oreochromis mossambicus ), a cladoceran ( Moina micrura ), and an oligochaete worm ( Branch iura sowerbyi ) (MRID 48770801 )

. A 96

- h LC 50 and confidence interval are listed in
Table 7 for each species

. Fish exhibited whitish lesions on their skin and fins after a few hours of exposure to concentrations of 262.4 mg ai/L and higher. They also show ed signs of respiratory distress (frequent surfacing, abnormal opercular movement, gasping, release of air bubbles from mouth, and loss of equilibrium). The oligochaete worms reacted by sharply coiling21

their bodies at the higher concentrations of acetic a cid (the study was not specific about which concentrations) . Their bodies gradually fragmented, resulting in death. Cladocerans were observed to exhibit decreased swimming activity before death.

Table 7

. LC 50 for freshwater fish, cladoceran, and worm exposed to acetic acid for 96
hours

LC 50 and Confidence Interval (mg ai/L)
Fish 272.87 (268.99

- 276.75) Cladoceran 163.72 (156.38

- 171.07)
Worm 14.90 (14.48

- 15.43)

T he chronic effects of acetic acid on tilapia were examined in a 90

- day outdoor study ( MRID
48770801 )

. No mortality occurred during the test. There were significant differences between the control and various treatment levels for the following: food consumption, food conversion efficiency, specific growth rate, yield, percent increase in weigh t , fecundity, and maturity index.
Table 8 provides the NOAEC value s for the various parameters that were measured.

Table 8

. NOAECs values for multiple parameter s of freshwater tilapia fish expos ed to
acetic acid for 90 days NOAEC (mg ai/L)
Food consumption 1.26 Food conversion efficiency 1.47 Specific growth rate 1.47 Yield 1.47 Percent increase in weight 1.47 Fecundity 1.47 Male maturity index 1.26 Female maturity index 16.79

Cairns et al. (1976) conducted a study to measure the 48

- h acute effects of acetic acid on two freshwater snail species ( Goniobasis livescens and Lymnaea emarginata angulata ) (Table 9 ). A limitation of the study is that the lake water used in the experiment was not tested to confirm the
absence of additional contaminants

, although the control performance was deemed normal. Furthermore, the Agency’s normal endpoint for acute toxicity effects on mollusks is 96 hours (a more conservative value) rather than 48 hours.

Table 9

. 48

- h acute toxicity values for two species of freshwater snail exposed to acetic acid

48

- h LC 50 (mg ai/L)
Goniobasis livescens 460 Lymnaea emarginata angulata 32022

Locke et al. (2009) documented the acute effects of acetic acid to two estuarine/marine species : threespine stickleback fish ( Gasterosteus acucleatus ) and the sand shrimp ( Crangon septemspinosa ) (Table 10 )

. The results of this study should be interpreted with caution as the
dose

- response curves were very steep for both organisms ( fish

– 0% morality at 0, 32, a nd 100 mg ai/L but 100% mortality at ≥ 320mg ai/L; shrimp

– 0 % mortality at 0, 5, and 500 mg ai/L, but
100% mortality at ≥ 500 mg ai/L).

Table 10

. Toxicity values for the threespine stickleback fish and the sand shrimp

96

- h LC 50 (mg ai/L) 96

- h NOAEC (m g ai/L) Threespine stickleback fish 178 100 Sand shrimp 158 50

Piola et al. ( 2010) tested the effectiveness of a 5% acetic acid solution (52,450 mg ai/L) to

manage tunicates, algae, tubeworm, bryozoans, and other fouling organisms. This experiment
demonstrated that acetic acid can be detrimental to marine/estuarine organisms at high
concentration s

. Likewise, Paetzold et al. (2008) reported the effects of 5% acetic acid on estuarine/marine amphipods and gastropods. The study showed that amphipods w ere much more
sensitive to the concentrated acetic acid exposures than the gastropods. All of the amphipods
were classified as “inactive” after 5 minutes and 90% of them were dead after 2

- 3 hours. In contrast, 70% of the gastropods were classified as “in active” at the 5 minute observation period, but most had completely recovered by the 5 to 9 day observation period. The Agency concludes
that high acetic acid concentrations (5%) are unlikely to be present in aquatic system s through runoff from the regist ered uses of sodium diacetate.

Aquatic Plants
BPPD used a n algal ( Scenedesmus quadricanda ) toxicity threshold of 4000 mg ai/L in their risk assessment of acetic acid (USEPA 2010). Two studies were available that documented the effects of acetic acid on aquatic plants. Table 11 shows the effects of acetic acid on the re

growth of hydrilla ( Hydrilla verticillata ); t he most sensitive IC 50 i s for dry weight at 549 mg ai/L (MRID 4877080 3 ). Academy of Natural Sciences (1960) reported the effects of acetic acid on freshwater diatoms ( Navicula seminulum var. hustedtii ) with a 120

- h LC 50 of 74 ppm.

Table 11

. The effect of a cetic acid on hydrilla

Characteristic IC 50 (mg ai/L)
Shoot length 851 New shoots 675 Dry weight 54923

TERRESTRIAL EFFECTS Terrestrial exposure to sodium diacetate and its degradates is expected to be negligible. Several
sodium diacetate applications occur in feed grinders/mixers, which are contained and usually located indoors. One use involves the application of sodium diacetate to silage as the grains are being loaded into the silos. The application is expected to occur in built

- up a reas of the farm resulting in low potential exposure to non

- target species. The most likely environmental exposure pathway is through applications to hay during the baling process on the field. However, given the short half

- life and practically non

- toxi c classification, it is unlikely that a

non

- target organism will be adversely affected.

Birds, Reptiles, and Land

- phase Amphibians In a chronic avian toxicity study, t urkey poults (50 days old) were exposed to sodium acetate in drinking water for 7 weeks ( Adams et al. 1969 ) . No mortalities occurred, but enlarged kidneys
were observed in the sod ium acetate treatment group at 6178 ppm . T herefore, a LOEL of 6178 ppm was established for sodium acetate. Adjusting for sodium diacetate (two acetates for every sodium), the LOEL is 3089 ppm

.

Data were not available for reptiles or land

- phase amphibians; thus, birds are used as a surrogate for these groups.

Mammals

A registrant

- submitted rat acute oral toxicity study for sodium diacetate reported an oral LD 50 of 5600 mg ai/kg ( US EPA 2008 ) . This endpoint classifies sodium diacetate as pr actically non

- toxic
to mammals. Several other rat studies were available from the human health effects risk

assessment in the RED (US EPA 1991 ) . The dermal LD 50 was reported a s > 2000 mg ai/kg

. A n 8

- h inhalation study induced a slight petechial hemorrhage in the lungs. Sodium diacetate is an eye irritant, which is expected because of its dissociation into acetic acid (a weak acid) when coming into contact with water. An eye irritation study in rabbits induced chemosis and redness
and a nother rabbit study documented severe corneal necrosis with a 15% solution

, but only trace injuries with a 5% solution. There wa s no dermal irritation on rabbits using a 50% solution.

A chronic study for the effects of sodium acetate ( a degradate of sodium diac e tate) on mice was available from the open literature ( Kavlock et al. 1987 ). The study monitored pregnant mice, specifically maternal weight change and mortality, and neonatal weig ht change and mortality.

N o effects (including sub

- lethal) were found at the limit dose tested, thus establishing a NOAEC of 1000 mg ai/kg

- day for sodium acetate. Table 12 provides the mammalian toxicity summary
for sodium diacetate and sodium acetate. Given that sodium diacetate contains two acetate molecules for each sodium ion, the estimated NOAEC for sodium diacetate is 500 mg ai/kg

- day

.24

Table 12 . Mammal toxicity information for sodium diacetate and sodium acetate Toxicity Route Value
Sodium Diacetate Acute oral 5600 mg ai/kg
Acute dermal > 2000 mg ai/kg
Acute inhalation Not determined Eye irritation Corneal involvement clearing in 8

- 21 days
Dermal irritation No irritation Skin sensitizer Not determined Sodium Acetate Chronic reproductive (NOAEC) 1000 mg ai/kg

- day

The metabolic pathways in mammals for sodium diacetate, acetic acid

, and acetate were
documented. Acetic acid is readily absorbed from the gastrointestinal tract and from the lungs (FASEB 1977, Clayton and Clayton 1982). It is rapidly and naturally incorporated into the intermediary metabolism by most tissues of the body (Clayton and Clayton 1982). A cetate is completely utilized in oxidative metabolism or in anabolic syntheses. Isotope experiments have shown acetate to be used in the formation of glycogen, carbohydrate intermediates, phospholipids, and fatty acids, as well as in cholesterol and stero id synthesis (Clayton and Clayton 1982, Geigy 1970, FASEB 1977). In addition, it participates in the acetylation of the amines and may be converted to alan ine by transamination and then incorporated into proteins of
the plasma, liver, kidney, gut mucosa, muscle, and brain (Geigy 1970). It has been estimated that the rat forms acetate at the rate of one percent of its body weight per day (FASEB 1977).

Terrestrial Invertebrates van Engelsdorp et al. 2008, test ed the effectiveness of acetic acid as a fumigant to control varroa mites in honey bee colonies. Varroa mites are a parasite and can greatly reduce honey bee colony size and productivity. Each h ive w as treated with 26,225 mg of acetic acid (50 mL of a
50% acetic acid solution). No bee or varroa mite mortality w as found in the hives treated with acetic acid. This experiment indicates that acetic acid is relatively non

- toxic to terrestrial
invertebrates.

Terrestrial Plants Information is not available rega rding the effects of sodium diacetate on terrestrial plants;
l ikewise, information is limited for acetic acid’s effects. Acetic acid is registered as a non

selective herbicide by OPP. The most recent risk assessment for acetic acid (USEPA 2010, DP
367372 ) describes the mode of action in plants as the disruption of the cuticle on the surface of plant leaves and stem, which results in a rapid desiccation and browning of the plant. The assessment indicates that to be efficacious, plants must be thoroughly d renched with the products ( 20% and 8% acetic acid ) for effective control to occur. A rate of 29.4 lb ai/A/application, four applications per year was assessed. This resulted in potential risks to non

- target birds, terrestrial25

insects, and plants. Howeve r, the application rates are far higher than the registered uses for sodium diacetate, making it unlikely that such risks would be present for sodium diacetate applications. Stopar ( 2008) reported phytotoxic effects in apple trees as a result of acetic acid applications for apple blossom thinning . The most common effects were the burning of leaf edges and partially stunted growth of young leaves; effects appeared a few days after spraying and lingered for 11 weeks. The effects were most pronounced at the 525 mg ai/L treatment
level

.

Incident Database Review On February 23, 2012, a review of the Ecological Incident Information System (EISS, version 2.1.1), which is maintained by the Agency’s Office of Pestic ide Programs, and the Avian Monitoring Information System (AIMS), which is maintained by the American Bird Conservancy, indicated no incident reports for sodium diacetate and its major degradates

– acetic
acid and sodium acetate. In addition to the incide nts recorded in EIIS, other incidents may have been reported to the Agency as aggregate counts of incidents occurring per product per quarter. Ecological incidents reported in aggregate reports include those categorized as “minor fish and wildlife” (W

- B), “minor plant” (P

- B), and “other non

- target” (ONT) incidents. “Other non

target” incidents include reports of adverse effects to insects and other terrestrial invertebrates. For sodium diacetate and its degradates, no incidents were contained in this dat abase.



### Risk to Non

- Listed and Listed Species

Direct adverse effects based on survival, growth, and reproduction to terrestrial and aquatic non

listed species from the use of sodium diacetate are not expected ( Table 13 ). This is based on
several lines of evidence:

 The registered uses of sodium diacetate are limited to either indoor uses or outdoor uses that are isolated and relatively contained. For the feed fermentation and dairy ration uses, applications usually occur indoors or directly at the site o f the silo. All treated feed that is used for livestock and poultry has the potential to be placed in the troughs of outdoor feedlots, but given the domestic surroundings ( e.g., farm buildings, farm house, animal houses) , it is unlikely to come into conta ct with many non

- target species ; listed species are unlikely to venture into such developed areas . For baled hay treatments that occur on the field, the risk of exposure from runoff is low; very high concentrations of acetic acid (major degradate) would b e necessary to change the pH of an aquatic system and cause toxic responses. Other terrestrial wildlife exposures via incidental use of baled hay in a
field would also likely be limited and not result in the consumption of concentrations high enough to cause an acute toxic response. Therefore, the anticipated environmental concentrations for sodium diacetate are expected to be below levels that could be of toxicological significance to non

- target terrestrial and aquatic organisms.26

 The available toxicity data for sodium diacetate and its degradates

– sodium acetate and
acetic acid

– indicate that these chemicals are practically non

- toxic to mammals on an acute basis and slightly toxic to practically non

- toxic to aquatic species. For terrestrial plants, acetic acid can cause phytotoxic damage (Stopar 2008) , if applied in high enough concentrations (8

- 20%) and amounts (e.g., drenching the plant leaves). The amount of
acetic acid that mi ght be expected in runoff waters is lower and probably would not result in “drenching” the entire plant, thus avoiding any major effects. There is evidence that should phytotoxic damage occur, recovery would take place within 2 months of the

exposure (Sto par 2008) . Ba r ring repeated acetic acid drenches, it is unlikely that there would be any long

- lasting effects to non

- target terrestrial plants. Toxicity data for aquatic plants indicate that some plants are more sensitive than others (diatoms versus alga e); however, it is unlikely that high enough concentrations of acetic acid would concentrate in a water body to cause a toxic response. Therefore, even if terrestrial and/or aquatic species were to come into contact with sodium diacetate

- treated grain, ha y,

or runoff water, direct exposure to it and its degradates at levels expected to cause effect s would be unlikely, based on its low toxicity and its degradation properties.

 Sodium diacetate dissociates into sodium acetate and acetic acid upon the additio n of
water. The half

- life of acetic acid is approximately 17.3 days in soil and 8.7 days in

water , indicating that the degradation is rapid. Acetic acid also is a normal component of metabolism in the human body and many other organisms. It plays an int egral role in

p roducing ATP during the Kreb’s c ycle. Thus, it is not expected to adversely affect non

target species.

Overall, the use of sodium diacetate is expected to have no effect to non

- listed and listed terrestrial and aquatic organisms, based on survival, growth, and reproduction.

Indirect Effects to Listed Species Since direct adverse effects are not expected for listed species based on survival, growth, and reproduction, indirect effects to terrestrial and aquatic listed species also are not ex pected.

Effects to Critical Habitat No adverse modifications to critical habitat for any terrestrial or aquatic listed species are expected from the use of sodium diacetate. This is based on the same lines of evidence as presented above.27

Table 13

. Potential risks to non

- listed and listed species associated with direct or indirect effects from the proposed application of sodium diacetate

Taxonomic Group Effects Endpoint 1 Direct Effects 2 Indirect Effects to Listed Species
Non

Listed Listed Potential Indirect Effects from Direct Effect to: 3 Aquatic vascular plants Measures of biomass No No No Not applicable

Aquatic non

vascular plants Measures of biomass No No No Not applicable

Terrestrial plants Measures of biomass

- NA 4 No No No Not applicable
Freshwater vertebrates Acute: mortality

Chronic: NOAEC growth & reproduction

- NA No No No Not applicable

Estuarine/marine vertebrates Acute: mortality

Chronic: NOAEC growth & reproduction

- NA No No No Not applicable

Freshwater invertebrates Acute: mortality

Chronic: NOAEC growth & reproduction

- NA No No No Not applicable

Estuarine/marine invertebrates Acute: mortality

Chronic: NOAEC growth & reproduction

- NA No No No Not applicable

Mammals Acute oral dose: mortality

Sub

- acute dietary: mortality and growth

- NA Chronic: growth and reproduction

- NA No No No Not applicable

Birds Acute oral dose: mortality

NA Sub

- acute dietary: mortality and growth Chronic: growth and reproduction

- NA No No No Not applicable

Terrestrial invertebrates Acute contact and oral:

mortality No No No Not applicable

1 Abbreviations: NA = toxicity data not available

2 Negligible exposures to non

- target organisms from sodium diacetate registered uses being indoors or contained (no spray drift, runoff, spillage). Therefore, adverse effects are not expected.

3 Direct effects to species may result in indirect effects to other species by changing availability of prey, habitat, and other factors important to survival and reproduction.

4 Acetic acid is registered as a non

- selective herbicide, so it is expected that if directly applied to

non

- target plants, there could be adverse effects; however, the usage on hay/silage/feed is not expected to come into contact with non

- target plants.28



### Bibliography

Academy of Natural Sciences. 1960. The sensitivity of aquatic life to certain chemicals commonly found in industrial wastes. Final report number RG

- 3965(C2R1), U. S. Public Health Service Grant, Academy of Natural Sciences, Philadelphia, PA. 89p. Adams, A. W., J. L. West , and A. J. Kahrs. 1969. Some effects on turkeys of nitrate in the drinking water. Poultry Science , 48(4): 1222

- 1229. Cairns Jr., V. J., D. I. Messenger, and W. F. Calhoun. 1976. Invertebrate response to thermal shock following exposure to acutely su b

- lethal concentrations of chemicals. Archives of Hydrobiology , 77(2): 164

- 175. Clayton, G. D., and F. E. Clayton, Eds. 1982. Patty’s Industrial Hygiene and Toxicology, 3 rd revised edition, Volume 2c. Wiley Interscience, NY. van Engelsdorp, D., R. M. Underwood, and D. L. Cox

- Foster. 2008. Short

- term fumigation of honey bee (Hymenoptera: Apidae) colonies with formic and acetic acids for the control
of Varroa destructor (Acari: Varroidae). Journal of Economic Entomology , 101(2):
256

- 264.
FASEB . 19 77. Evaluation of the health aspects of acetic acid, sodium acetate, and sodium diacetate as food ingredients. NTIS PB

- 274 670. Fischer, H. and Kuzyakov, Y. (2010). Sorption, microbial uptake and decomposition of acetate
in soil: transformations revealed by position

- specific 14C labeling. Soil Biology & Biochemistry 42:186

- 192. Geigy S. A., J. R. 1970. Documenta, Geigy., 7 th ed. Basle; as cited in FAO/WHO World Health Organ. Techn. Rep. Ser. No. 539, 1974. Kavlock, R. J., R. D. Short, Jr., and N. Chern off. 1987. Further evaluation of an in vivo teratology screen. Teratogenesis, Carcinogenesis, and Mutagenesis , 7: 7

- 16. Lindsay, W. 1979 Chemical Equilibria in Soils, Wiley Press

. p. 376

- 383 Locke, A., K. G. Doe, W. L. Fairchild, P. M. Ja ckman, and E. J. Reese. 2009. Preliminary evaluation of effects of invasive tunicate management with acetic acid and calcium hydroxide on non

- target marine organisms in Prince Edward Island, Canada. Aquatic

Invasions , 4(1): 221

- 236. MRID 48770802 Janssen, C. R., E . Q. Espiritu, and G. Persoone. 1993. Evaluation of the new “enzymatic inhibition” criterion for rapid toxicity testing with Daphnia magna . In: Soares, A., and P. Cukow (Eds.), Progress in Standardization of Aquatic Toxicity Tests,
Lewis Publishers: 7 1

- 81. MRID 48770801 Saha, N. C., F. Bhunia, and A. Kaviraj. 2006. Comparative toxicity of three organic acids to freshwater organisms and their impact on aquatic ecosystems. Human and Ecological Risk Assessment: An International Journal , 12(1): 192

- 2 02. MRID 48770803 Spencer, D. F. and G. G. Ksander. 1995. Influence of acetic acid on regrowth of dioecious hydrilla from root crowns. Journal of Aquatic Plant Management , 33: 61

- 63.29

Paetzold, S. C., J. Davidson, D. Giberson. 2008. Responses of Mitr ella lunata and Caprella spp., potential tunicate micropredators, in Prince Edward Island estuaries to acetic acid
anti

- fouling treatments. Aquaculture , 285: 96

- 101. Piola, R. F., R. A. Dunmore, B. M. Forrest. 2009. Assessing the efficacy of spray

- deli vered
‘eco

- friendly’ chemicals for the control and eradication of marine fouling pests. Biofouling , 26(2): 187

- 203. Stopar, M. 2008. Vegetable oil emulsions, NaCl, CH 3 COOH and CaS x as organically acceptable apple blossom thinning compounds. European J ournal of Horticulture
Science , 73(2): 55

- 61. United States Environmental Protection Agency. 1991. Reregistration eligibility document sodium diacetate. Special Review and Reregistration Division, Office of Pesticide Programs, Washington, DC. United States Environmental Protection Agency. 2004. Overview of the ecological risk assessment process in the Office of Pesticide Programs. Office of Pesticide Programs, Washington, DC. United States Environmental Protection Agency. 2008. EFED proble m formulation for acetic acid (PC 044001) and sodium diacetate (PC 04408) registration review. DP 344770. Environmental Fates and Effects Division, Office of Pesticide Programs, Washington,
DC. United States Environmental Protection Agency. 2010. Scien ce review in support of the end use product, 81936

- R Summer Set All Down Concentrate and Summer Set All Down Herbicide. Biopesticide and Pollution Prevention Division, Office of Pesticide Programs, Washington, DC. United States Fish and Wildlife Service ( USFWS) and National Marine Fisheries Service (NMFS). 1998. Endangered Species Consultation Handbook: Procedures for Conducting Consultation and Conference Activities Under Section 7 of the Endangered Species Act. Final Draft. March 1998.30



### ECOTOX Pape rs

Acceptable for EcoTox and OPP May 2011

Adams, A. W., West, J. L., and Kahrs, A. J. (1969). Some Effects on Turkeys of Nitrate in the Drinking Water. Poult. Sci. 48: 1222

- 1229.

EcoReference No.: 35559 Chemical of Concern: NACE,NaNO3; Habitat : T; Effect Codes : BCM,BEH,CEL,GRO,MOR,PHY; Code : LITE EVAL CODED (NACE,NaNO3).

Used qualitatively in the assessment.

Anderson, B. G. (1946). The Toxicity Thresholds of Various Sodium Salts Determined by the Use of Daphnia magna. Sewage Works J. 18: 82

- 87.

EcoReference No.: 2130 Chemical of Concern: As,AsO3Na,AsO4Na,BOR,BORON,BRA,CIT,CN,Halides,NACE,NACIO,NAI,Na2Cr2, Na2P,Na3C,Na3P,NaBS,NaBr,NaCBN,NaCN,NaCO,NaCl,NaClO,NaCr,NaID,NaNO3, NaOH,NaSO4,SBS,SFL; Habitat : A; Effect Codes : PHY; Code : LITE EVAL COD ED (BOR,Halides,NACE,Na2Cr2,Na3C,NaBS,NaBr,NaCN,NaCl,NaID,NaNO3,NaOH,SBS, SFL), NO CONTROL (BRA,CIT), NO EFED CHEM (AsO3Na,AsO4Na,BORON,Na2P,Na3P,NaCBN,NaCO,NaClO,NaCr,NaSO4), OK (As,CN).

Not used because the endpoint was not useful.

Anderson, B. G. (1944) . The Toxicity Thresholds of Various Substances Found in Industrial Wastes as Determined by the Use of Daphnia magna. Sewage Works J. 16: 1156

- 1165.

EcoReference No.: 2171 Chemical of Concern: ACAC,AN,AlCl,AlKS,AlS,As,AsO4Na,BZO,Ba,CIT,CaCl2,CoCl,CrO4,Cu Cl,CuS,ETH N,FeCl,FeCl3,FeRS,HCL,Halides,K2Cr2O7,KCl,KPM,LLA,MOL,NHCl,NHOH,NHSO 4,NaCBN,NaCO,NaCl,NaNO3,NaOH,NaSO4,OXAC,PL,SAAAS,SUA,ZnS; Habitat : A; Effect Codes : PHY; Code : LITE EVAL CODED (ACAC,BZO,CIT,CaCl2,CrO4,ETHN,FeRS,HCL,Halides,MOL,NHOH,NaCl,N aNO3,N aOH,OXAC,SUA,ZnS), NO CONTROL (CuS), NO EFED CHEM (AN,AlCl,AlKS,AlS,AsO4Na,Ba,CoCl,FeCl,FeCl3,K2Cr2O7,KCl,KPM,NHCl,NHSO4, NaCBN,NaCO,NaSO4,PL,SAAAS), NO ENDPOINT (CuS), OK (As,CuCl,LLA).

Not the lowest endpoint, test duration was 16 hours instead of 48 hours.

Barry, J. D. and Polavarapu, S. (2004). Feeding Activity and Attraction of Blueberry Maggot (Diptera: Tephritidae) to Protein Baits, Ammonium Acetate, and Sucrose. J. Econ. Entomol. 97: 1269

- 1277.31

EcoReference No.: 87498 Chemical of Concern: NH AC; Habitat : T; Effect Codes : BEH; Code : LITE EVAL CODED (NHAC).

Test duration was too short.

Begum, S. J., Mohanachari, V., and Indira, K. (1984). Changes in Energy Fuels of Fish During Ammonia Stress. Environ. Ecol. 2: 286

- 289.

EcoReference No.: 119 Chemical of Concern: NHAC; Habitat : A; Effect Codes : BCM,GRO; Code : LITE EVAL CODED (NHAC).

Test duration was not 96 hours.

Bodega, G., Suarez, I., Boyano, M. C., Rubio, M., Villalba, R. M., Arilla, E., Gonzalez

- Guijarro, L., and Fernandez, B. (1993). High Ammonia Diet: Its Effect on the Glial Fibrillary Acidic Protein (GFAP). Neurochem. Res. 18: 971

- 975.

EcoReference No.: 151921 Chemical of Concern: NHAC; Habitat : T; Effect Codes : ACC,BCM,BEH,GRO; Code : LITE EVAL CODED (NHAC).

Endp oints were not reported in units useful for the risk assessment.

Boyano

- Adanez, M. C., Bodega, G., Barrios, V., and Arilla, E. (1996). Response of Rat Cerebral Somatostatinergic System to a High Ammonia Diet. Neurochem.Int. 29: 469

- 476.

EcoReference No.: 113073 Chemical of Concern: NHAC; Habitat : T; Effect Codes : BCM,GRO; Code : LITE EVAL CODED (NHAC).

Endpoints were not reported in units useful for the risk assessment.

Corsi, S. R., Geis, S. W., Bowman, G., Failey, G. G., and Rutter, T. D. (2009). A quatic Toxicity of Airfield

- Pavement Deicer Materials and Implications for Airport Runoff. Environ. Sci. Technol. 43: 40

- 46.

EcoReference No.: 115482 Chemical of Concern: KACE; Habitat : A; Effect Codes : GRO,MOR,POP,REP; Code : LITE EVAL CODED (KACE).

Endpoint was not useful for the risk assessment.

Dabrowska, H. and Sikora, H. (1986). Acute Toxicity of Ammonia to Common Carp (Cyprinus carpio L.). Pol. Arch. Hydrobiol. 33: 121

- 128.32

EcoReference No.: 12711 Chemical of Concern: NHAC,NHCl,NHN,NHOH,NHS; Habitat : A; Effect Codes : MOR; Code : LITE EVAL CODED (NHAC,NHN,NHOH), NO EFED CHEM (NHCl,NHS).

Duration of the test was not 96 hours.

De Avila Fortes, M., Oliveira de Sousa, R., Schmidt, F., Costa de Oliveira, A., and Vahl, L. C. (2009). Calcium Ef

fects on Acetic Acid Toxicity in Rice. Commun. Soil Sci. Plant Anal. 40: 2536

- 2544.

EcoReference No.: 151918 Chemical of Concern: ACAC; Habitat : A; Effect Codes : ACC,BCM,GRO; Code : LITE EVAL CODED (ACAC).

Endpoints were not reported in units useful for the risk assessment.

DeYoung, D. J., Bantle, J. A., Hull, M. A., and Burks, S. L. (1996). Differences in Sensitivity to Developmental Toxicants as seen in Xenopus and Pimephales Embryos. Bull. Environ. Contam. Toxicol. 56(1): 143

- 150.

EcoReference N o.: 16432 Chemical of Concern: NACE; Habitat : A; Effect Codes : GRO,MOR; Code : LITE EVAL CODED (NACE).

The test was 120 hours in duration rather than 96 hours.

Dial, E. J., Hall, L. R., Romero, J. J., and Lichtenberger, L. M. (1996). Rats with Gastri tis have Increased Sensitivity to the Gastrin Stimulatory Effects of Luminal Ammonia. Gastroenterology 110: 801

- 808.

EcoReference No.: 151841 Chemical of Concern: NHAC; Habitat : T; Effect Codes : BCM,BEH,CEL,GRO; Code : LITE EVAL CODED (NHAC).

Endpoints were not reported in units useful for the risk assessment.

Djian, C., Ponchet, M., and Cayrol, J. C. (1994). Nematocidal Properties of Carboxylic Acids and Derivatives. Pestic. Biochem. Physiol. 50: 229

- 239.

EcoReference No.: 96598 Chemical of Concern: ACAC,ADC,BZO,DBE,EP,FMA,GLYA,OXAC,PPA,SCA; Habitat : A; Effect Codes : MOR; Code : LITE EVAL CODED (ACAC,ADC,BZO,EP,OXAC,PPA,SCA), NO EFED CHEM (DBE,FMA,GLYA).

Endpoints were not reported in units useful for the risk assessment.

Fort, D. J., Mc Laughlin, D. W., Rogers, R. L., and Buzzard, B. O. (2003). Evaluation of the33

Developmental Toxicities of Ethanol, Acetaldehyde, and Thioacetamide Using FETAX. Drug Chem. Toxicol. (N.Y.) 26: 23

- 34.

EcoReference No.: 82000 Chemical of Concern: ACAC,ETHN,PC B; Habitat : A; Effect Codes : GRO,MOR; Code : LITE EVAL CODED (ACAC,ETHN), NO EFED CHEM (PCB), NO MIXTURE (PCB).

Study was evaluated, but classified as “invalid.”

Greer, L. and Dole, J. M. (2005). Defoliation of Woody Cut Stems with Preharvest, Less To xic Chemical and Postharvest Environmental Methods. HortTechnology 15: 376

- 380.

EcoReference No.: 118123 Chemical of Concern: ACAC,DMP,EPH,NONA; Habitat : T; Effect Codes : CEL,PHY; Code : LITE EVAL CODED (ACAC,EPH,NONA), NO EFED CHEM (DMP).

Study was evaluated, but classified as “invalid.”

Heath, R. R., Epsky, N. D., Guzman, A., Dueben, B. D., Manukian, A., and Meyer, W. L. (1995). Development of a Dry Plastic Insect Trap with Food

- Based Synthetic Attractant for the Mediterranean and Mexican Fruit Fli es (Diptera: Tephritidae). J. Econ. Entomol. 88: 1307

- 1315.

EcoReference No.: 151926 Chemical of Concern: NHAC; Habitat : T; Effect Codes : BEH; Code : LITE EVAL CODED (NHAC).

Endpoints were not reported in units useful for the risk assessment.

Hernan dez, C., Martin, M., Bodega, G., Suarez, I., Perez, J., and Fernandez, B. (1999). Response of Carp Central Nervous System to Hyperammonemic Conditions: An Immunocytochemical Study of Glutamine Synthetase (GS), Glial Fibrillary Acidic Protein (GFAP) and 70 kDa Heat

- Shock Protein (HSP70). Aquat. Toxicol. 45(2

- 3): 195

- 207.

EcoReference No.: 19920 Chemical of Concern: NH,NHAC; Habitat : A; Effect Codes : BCM,MOR; Code : LITE EVAL CODED (NHAC), NO EFED CHEM (NH).

Endpoint was not useful for the risk assessm ent.

Hirazawa, N., Oshima, S. I., Hara, T., Mitsuboshi, T., and Hata, K. (2001). Antiparasitic Effect of Medium

- Chain Fatty Acids Against the Ciliate Cryptocaryon irritans Infestation in the Red Sea Bream Pagrus major. Aquaculture 198: 219

- 228.

EcoRefere nce No.: 105099 Chemical of Concern: ACAC,CAC,CRA,NONA; Habitat : A; Effect Codes :34

MOR,PHY; Code : LITE EVAL CODED (ACAC,CAC,CRA,NONA).

Endpoint was not useful for the risk assessment.

Iishi, H., Tatsuta, M., Baba, M., Mikuni, T., Yamamoto, R., Iseki, K., Yano, H., Uehara, H., and Nakaizumi, A. (1997). Enhancement by Monochloramine of the Development of Gastric Cancers in Rats: a Possible Mechanism of Helicobacter pylori

- Associated Gastric Carcinogenesis. J. Gastroenterol. 32: 435

- 441.

EcoReference No .: 151911 Chemical of Concern: NHAC,NaHCT; Habitat : T; Effect Codes : CEL,GRO,PHY; Code : LITE EVAL CODED (NHAC), NO EFED CHEM (NaHCT).

Endpoints were not reported in units useful to the risk assessment.

Insausti, A. M., Gaztelu, J. M., Gonzalo, L. M., Romero

- Vives, M., Barrenechea, C., Felipo, V., and Insausti, R. (1997). Diet Induced Hyperammonemia Decreases Neuronal Nuclear Size in Rat Entorhinal Cortex . Neurosci. Lett. 231: 179

- 181.

EcoReference No.: 151927 Chemical of Concern: NHAC; Habitat : T ; Effect Codes : CEL; Code : LITE EVAL CODED (NHAC).

Endpoint was not reported in units useful to the risk assessment.

Jester, J. V., Molai, A., Petroll, W. M., Parker, R. D., Carr, G. J., Cavanagh , H. D., and Maurer, J. K. ( 2000). Quantitative Characterization of Acid

- and Alkali

- Induced Corneal Injury in the Low

- Volume Eye Test. Toxicol. Pathol. 28: 668

- 678.

EcoReference No.: 151823 Chemical of Concern: ACAC,NaOH; Habitat : T; Effect Codes : CEL,GRO,MOR,PHY; Code : LITE EVAL CODED (ACAC,NaOH).

Endpoints were not reported in units useful to the risk assessment.

Joseph, R. M., Devineni, A. V., King, I. F. G., and Heberlein, U. (2009). Oviposition Preference for and Positional Avoidance of Aceti c Acid Provide a Model for Competing Behavioral Drives in Drosophila. Proc. Natl. Acad. Sci. U.S.A. 106: 11352

- 11357.

EcoReference No.: 151928 Chemical of Concern: ACAC,HCL,SUA; Habitat : T; Effect Codes : BEH,CEL,REP; Code : LITE EVAL CODED (ACAC,HCL,SUA), TARGET (HCL).

Duration of the experiment was not in accord with OPP Guidelines.

Kane, M. T. (1979). Fatty Acids as Energy Sources for Culture of One

- Cell Rabbit Ova to Viable Morulae. Biol. Reprod. 20: 323

- 332.35

EcoReference No.: 101665 C hemical of Concern: ACAC,OLEA,PPA; Habitat : T; Effect Codes : GRO; Code : LITE EVAL CODED (ACAC,PPA), NO EFED CHEM (OLEA).

Endpoint was not reported in units useful to the risk assessment.

Kavlock, R. J., Short, R. D. Jr., and Chernoff, N. (1987). Furt her Evaluation of an In Vivo Teratology Screen. Teratog. Carcinog. Mutagen. 7: 7

- 16.

EcoReference No.: 70488 Chemical of Concern: 24D,24DXY,BMY,CBL,CCA,DM,EN,MRX,Maneb,NACE,PNB,PPCP,PPGL,Zineb; Habitat : T; Effect Codes : GRO,MOR,REP; Code : LITE EVAL CODED (24D,24DXY,BMY,CBL,DM,Maneb,NACE,PNB), NO EFED CHEM (CCA,EN,MRX,PPCP,PPGL,Zineb).

Evaluated as “qualitative” and used in the risk assessment.

Kazumori, H., Ishihara, S., Fukuda, R., and Kinoshita, Y. (2002). Time

- Course Changes of ECL Cell Markers i n Acetic Acid

- Induced Gastric Ulcers in Rats. Aliment. Pharmacol. Ther. 16: 10

- 19.

EcoReference No.: 103295 Chemical of Concern: ACAC; Habitat : T; Effect Codes : BCM,CEL; Code : LITE EVAL CODED (ACAC).

Endpoints were not reported in units that were u seful to the risk assessment.

Locke, A., Doe, K. G., Fairchild, W. L., Jackman, P. M., and Reese, E. J. (2009). Preliminary Evaluation of Effects of Invasive Tunicate Management with Acetic Acid and Calcium Hydroxide on Non

- Target Marine Organisms in Princ e Edward Island, Canada. Aquat.
Invasions 4: 221

- 236.

EcoReference No.: 115787 Chemical of Concern: ACAC,CIT,HCL; Habitat : A; Effect Codes : GRO,MOR; Code : LITE EVAL CODED (ACAC), NO BACTERIA (HCL), NO CONC (CIT).

Evaluated as “qualitative” and used in the risk assessment.

Lynch, J. M. (1980). Effects of Organic Acids on the Germination of Seeds and Growth of Seedlings. Plant Cell Environ. 3: 255

- 259.

EcoReference No.: 101602 Chemical of Concern: ACAC,BZO,CIT,CaCO3,FMA,LLA,PPA,SCA; Habitat : T;
E ffect Codes : ACC,GRO,REP; Code : LITE EVAL CODED (ACAC,BZO,CIT,LLA,PPA,SCA), NO EFED CHEM (CaCO3,FMA).

Endpoints were not reported in units useful to the risk assessment.36

Mayer, D. F., Lunden, J. D., Kovacs, G., and Miliczky, E. R. (2001). Field Evaluati on of Non

Pesticide Chemicals as Honey Bee Repellents. In: L.P.Elzunces, C.Elissier, & G.B.Lewis (Eds.), Hazards of Pesticides to Bees, Institute National de la Recherche Agronomique, Paris, France 159

- 168.

EcoReference No.: 81711 Chemical of Concern: 3

- OCT,ACAC,ATC,BOR,BPRO,C6OH,C8OH,CAC,CASTOR,CBNDS,CF,CRA,CRV,C WO,CaCO3,Captan,DBAC,DIC,DMDS,DMZ,DNS,EGL,ETHB,FAR,FTTCl,H3PO4,HT S,IMC,IND,IPA,LIM,LIN,MAT,NCTN,OCRE,PCRE,PHTH,PL,PPCP,PPNOL,SFR,TM L,nBUT; Habitat : T; Effect Codes : BEH; Code : LITE EVAL CODE D (ACAC,BPRO,C8OH,CASTOR,CBNDS,CRA,CRV,CWO,Captan,DBAC,DMDS,DMZ, DNS,EGL,ETHB,FAR,FTTCl,H3PO4,HTS,IMC,IND,LIM,MAT,NCTN,OCRE,PPNOL, SFR,TML,nBUT), NO EFED CHEM (ATC,C6OH,CF,CaCO3,DIC,IPA,LIN,PHTH,PL,PPCP), NO EFFECT (BOR,CAC,PCRE,PL), NO MIXTURE (PHTH).

Duration of the experiment was not in accord with OPP Guidelines.

Mollet, P. (1976). Lack of Proof of Induction of Somatic Recombination and Mutation in Drosophila by Methyl

- 2

- Benzimidazole Carbamate, Dimethyl Sulfoxide and Acetic Acid. Mutat. Res. 40: 383

- 388.

EcoReference No.: 104295 Chemical of Concern: ACAC,CBD; Habitat : T; Effect Codes : CEL,MOR; Code : LITE EVAL CODED (ACAC,CBD).

Duration of the experiment was not in accord with OPP Guidelines.

Paetzold, S. C., Davidson, J., and Giberson, D. ( 2008). Responses of Mitrella lunata and Caprella spp., Potential Tunicate Micropredators, in Prince Edward Island Estuaries to Acetic Acid Anti

- Fouling Treatments. Aquaculture 285: 96

- 101.

EcoReference No.: 151824 Chemical of Concern: ACAC; Habitat : A; Effect Codes : BEH,MOR,POP; Code : LITE EVAL CODED (ACAC).

Evaluated as “qualitative” and used in the risk assessment.

Parkash, R. and Vandna (1994). Latitudinal Differentiation in Alcoholic Utilisation and Desiccation

- Starvation Tolerance in Drosophila kikkawai Populations from India. Korean J. Genet. 16: 217

- 224.

EcoReference No.: 103292 Chemical of Concern: ACAC,ETHN,IPA,PPNOL,nBUT; Habitat : T; Effect Codes : MOR; Code : LITE EVAL CODED (ACAC,ETHN,PPNOL,nBUT), NO EFED CHEM (IPA).37

Evaluated, but found to be “invalid.”

Pelacho, A. M., Martin

- Closas, L., and Sanfeliu, J. L. I. (1999). In Vitro Induction of Potato Tuberization by Organic Acids. Potato Res. 42: 585

- 591.

EcoReference No.: 101664 Chemical of Concern: ACAC,HCL,PPA,SCA; Habitat : T; E ffect Codes : GRO; Code : LITE EVAL CODED (ACAC,HCL,PPA,SCA).

Endpoints were not reported in units that were useful to the risk assessment.

Piola, R. F., Dunmore, R. A., and Forrest, B. M. (2010). Assessing the Efficacy of Spray

Delivered 'Eco

- Friendly' C hemicals for the Control and Eradication of Marine Fouling
Pests. Biofouling 26: 187

- 203.

EcoReference No.: 151917 Chemical of Concern: ACAC,NaHCT; Habitat : A; Effect Codes : MOR,POP; Code : LITE EVAL CODED (ACAC), NO EFED CHEM (NaHCT).

Evaluated as “qualitative” and used in the risk assessment.

Rao, D. N. and Mikkelsen, D. S. (1977). Effect of Acetic, Propionic, and Butyric Acids on Young Rice Seedlings' Growth. Agron. J. 69: 923

- 928.

EcoReference No.: 42791 Chemical of Concern: ACAC,PPA; Habitat : T; Effect Codes : GRO; Code : LITE EVAL CODED (ACAC,PPA).

Endpoints were not reported in units that were useful to the risk assessment.

Rotstein, J. B. and Slaga, T. J. (1988). Acetic Acid, a Potent Agent of Tumor Progression in the Multistage Mouse Sk in Model for Chemical Carcinogenesis. Cancer Lett. 42: 87

- 90.

EcoReference No.: 103294 Chemical of Concern: ACAC; Habitat : T; Effect Codes : CEL,MOR,PHY; Code : LITE EVAL CODED (ACAC).

Endpoint was not reported in units useful to the risk assessment.

Sashikala, R., Krishna Mohan, P., and Indira, K. (1985). Protein Degradation and Transamination Patterns in a Fresh Water Fish Under Ambient Ammonia Stress. Environ. Ecol. 3: 496

- 499.

EcoReference No.: 113390 Chemical of Concern: NHAC; Habitat : A; Ef fect Codes : BCM,MOR; Code : LITE EVAL CODED (NHAC).

Duration of the experiment was not 96 hours.38

Sharma, S., Chanemougasoundharam, A., Sarkar, D., and Pandey, S. K. (2004). Carboxylic Acids Affect Induction, Development and Quality of Potato (Solanum tuberosum L.) Microtubers Grown In Vitro from Single

- Node Explants. Plant Growth Regul. 44: 219

- 229.

EcoReference No.: 101661 Chemical of Concern: ACAC,FMA,PPA; Habitat : T; Effect Codes : BCM,GRO,POP; Code : LITE EVAL CODED (ACAC,PPA), NO EFED CHEM (F MA).

Endpoints were not reported in units that were useful to the risk assessment.

Stopar, M. (2008). Vegetable Oil Emulsions, NaCl, CH3COOH and CaSx as Organically Acceptable Apple Blossom Thinning Compounds . Eur. J. Hortic. Sci. 73: 55

- 61.

EcoReferen ce No.: 118202 Chemical of Concern: ACAC,CaPS,Halides,NaCl,SOYBN; Habitat : T; Effect Codes : BCM,GRO,PHY,REP; Code : LITE EVAL CODED (ACAC,CaPS,Halides,NaCl,SOYBN).

Evaluated as “qualitative” and used in the risk assessment.

Taylor, P. W. and Glenn, R . A. (2008). Toxicity of Five Therapeutic Compounds on Juvenile Salmonids. N. Am. J. Aquacult. 70: 175

- 183.

EcoReference No.: 107284 Chemical of Concern: ACAC,CuS,FML,HOX,KPM; Habitat : A; Effect Codes : MOR; Code : LITE EVAL CODED (ACAC,CuS,HOX), NO E FED CHEM (FML,KPM).

Endpoints were not useful and/or endpoints were not the lowest values.

Terhaar, C. J., Ewell, W. S., Dziuba, S. P., and Fassett, D. W. (1972). Toxicity of Photographic Processing Chemicals to Fish. Photogr. Sci. Eng. 16: 370

- 377.

Eco Reference No.: 14566 Chemical of Concern: ACAC,Ag,Al,AlKS,BRA,CIT,FML,FeCl,FeCl3,K2Cr2O7,NACE,NH,NHTC,NHTS,Na 3P; Habitat : A; Effect Codes : MOR; Code : LITE EVAL CODED (ACAC,BRA,CIT,NACE), NO EFED CHEM (Al,AlKS,FML,FeCl,FeCl3,K2Cr2O7,NH,NHTC,NHTS,Na3P), OK (Ag).

Endpoints were not useful to the risk assessment.

Thompson, C. R., Kats, G., and Lennox, R. W. (1979). Phytotoxicity of Air Pollutants Formed by High Explosive Production. Environ. Sci. Technol. 13: 1263

- 1268.

EcoReference No.: 54817 Chemical of Concern: ACAC,SO2; Habitat : T; Effect Codes : PHY; Code : LITE EVAL CODED (ACAC,SO2). \39

Endpoints were not reported in units that were useful to the risk assessment.

Treverrow, N. L. (1991). Rice Bloodworm, Toxicity of Fatty Acids, 1981. Insectic. Acaric.
Tests 16: 297

- (15L).

EcoReference No.: 103759 Chemical of Concern: ACAC,CAC,CRA,FMA,PPA; Habitat : A; Effect Codes : MOR; Code : LITE EVAL CODED (ACAC,CAC,CRA,PPA), NO EFED CHEM (FMA).

Endpoint was not reported in units that were useful to the risk assessment.

Union Carbide Corp. (1978). The Acute Toxicity of Sodium Acetate to the Bluegill Sunfish Lepomis macrochirus Rafinesque with Attachments and Cover Letter Dated 033178. EPA/OTS Doc. #88

- 7800120 48 p. (NTIS/OTS0200477).

EcoReference No.: 1 52077 Chemical of Concern: NACE; Habitat : A; Effect Codes : BEH,MOR; Code : LITE EVAL CODED (NACE).

Non

- definitive endpoint and study duration was not in accord with OPP Guidelines.

Utz, L. R. P. and Bohrer, M. B. C. (2001). Acute and Chronic Toxicity of Potassium Chloride (KCl) and Potassium Acetate (KC2H3O2) to Daphnia similis and Ceriodaphnia dubia (Crustacea; Cladocera). Bull. Environ. Contam. Toxicol. 66: 379

- 385.

EcoReference No.: 62282 Chemical of Concern: KACE,KCl; Habitat : A; Effect Codes : GRO,MOR,REP; Code : LITE EVAL CODED (KACE), NO EFED CHEM (KCl).

Not the most sensitive endpoints and study duration was not always in accord with OPP Guidelines.

Van Engelsdorp, D., Underwood, R. M., and Cox

- Foster, D. L. (2008). Short

- Term Fumigation of Honey Bee (Hymenoptera: Apidae) Colonies with Formic and Acetic Acids for the Control of Varroa destructor (Acari: Varroidae). J. Econ. Entomol. 101: 256

- 264.

EcoReference No.: 151934 Chemical of Concern: ACAC,FMA; Habitat : T; Effect Codes : MOR,POP; Code : LITE EVAL CODED (ACAC), NO EFED CHEM (FMA).

Evaluated as “qualitative” and used in the risk assessment.

Wallace, J. M. and Whitehand, L. C. (1980). Adverse Synergistic Effects Between Acetic, Propionic, Butyric and Valeric Acids on the Growth of Wheat Seedling Roots. Soil Biol. Biochem. 12: 445

- 446.

EcoReference No.: 101600 Chemical of Concern: ACAC,PPA; Habitat : T; Effect Codes : GRO; Code : LITE40

EVAL CODED (ACAC,PPA).

Mixture and units were not useful to the risk as sessment.

Weissinger, W. R. and Beuchat, L. R. (2000). Comparison of Aqueous Chemical Treatments to Eliminate Salmonella on Alfalfa Seeds. J. Food Prot. 63: 1475

- 1482.

EcoReference No.: 101729 Chemical of Concern: ACAC,CIT,CaOCl,EDTA,EPXA,HOX,LLA,NaHCT; Habitat : T; Effect Codes : REP; Code : LITE EVAL CODED (ACAC,CIT,EPXA,HOX,LLA), NO EFED CHEM (CaOCl,EDTA,NaHCT).

Duration of the test was only three days.

Wu, Q. T., Deng, J. C., Long, X. X., Morel, J. L., and Schwartz, C. (2006). Selection of Appropr iate Organic Additives for Enhancing Zn and Cd Phytoextraction by Hyperaccumulators. J. Environ. Sci. 18: 1113

- 1118.

EcoReference No.: 114088 Chemical of Concern: ACAC,CIT,EDTA,OXAC; Habitat : T; Effect Codes : BCM,POP,REP; Code : LITE EVAL CODED (ACAC ,CIT,OXAC), NO EFED CHEM (EDTA).

Endpoints were not reported in units useful for the risk assessment.

Zurowski, D., Dobrek, L., Bugajski, A., and Thor, P. J. (2008). The Role of Sensory C

- Fibers in Response of Vagal Afferent Stimulation by Gastric Distens ion in Rats with Experimental Chronic Gastric Ulcer. J. Physiol. Pharmacol. 59: 179

- 189.

EcoReference No.: 151795 Chemical of Concern: ACAC,CPS; Habitat : T; Effect Codes : PHY; Code : LITE EVAL CODED (ACAC,CPS).

Endpoint was not reported in units use ful to the risk assessment.41 Sodium Diacetate
CH3COONa

· CH3COOH

Acetic Acid
CH 3 COOH Sodium Acetate
CH3COONa

CH 3 COO ˉ 2CO 2 2 H 2 O Na +

2CO 2 CH 4

or C 2 H 6 

### Appendix A

. Degradation Pathways of Sodium Diacetate (MRID 2058971)

Dissociation

+ O 2

2CH 3 COO ˉ

Anarobic Aerobic