UNITED STATES ENVIRONMENTAL PROTECTION AGENC Y

WASHINGTON

, D.C. 20460

N o v ember 18

, 2 0 15 O F F ICE OF C H EMIC AL SA F E TY

A N D POLLUT I ON P REVENT I ON

S UBJECT : Na ph t h a l ene Acetates: Hu man H ea l t h Ri sk Assess m e n t for a P ro p osed Ne w
Use on P omeg r anate

.

P C Co d e : 05600 1

, 056002

, 056 00 3, 0 56 00 4

, 056007

, 056008

D e cis i on No

. : 495 1 05

, 495110

P e t it i o n No.: N / A
Ri s k A s ses s me nt Ty p e: S i ngle C h e m i ca l Aggregate

TXRNo. : N I A

MRID N o. : N I A DP B arcode: 0 423 6 54

, 0 423 656

Reg i st r at i o n No

. : 54 8 1-42 9

, 54 8 1

- 433

R eg ul at o ry Ac ti o n : Sec t i o n 3

Case N o

. : 0 379

CAS No .: 2 1 22

- 7 0- 5

4 0 CFR : § 1 80 .1 55

FROM: A u st in Wray

, Ph

. D

. , Ri s k Assessor / T ox i cologis t 

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, C h em i st/ OR E Assesso r**~c--r~** 

### - Risk Assess m e nt Bra n c h 4

Hea l t h Effects Di visio n (7509P)

THRO U G H : E li ssa R eaves
, Ph

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., B r anc h C hi ef

Ri sk Assessmen t Branc h 4

H ea lt h Effects Di v i s i o n (7509 P )

T O: Sid n ey J ackson/ B ar ba ra Mad d e n Risk In tegratio n
, Min or Use & Eme r ge n cy R e spo n se Br anc h

R eg i st r a ti o n Di v i s i o n (7505 P )

T h i s document provides th e H ea l th E ffects Di v i s i o n ' s ( H E D 's) r i s k assess m e n t fo r t h e Sec t io n 3

use fo r n ap h t h a l e n e ace t ates o n p omegra n ate

. T h e d oc um e nt h as bee n rev i se d to incl ude an

assessme n t of aggrega t e r i sk fr o m r es id e n t i a l expos ur es to n a ph t h a l e ne ace t a t es.

Page I of791.0 EXECUT I VE SUMMARY

... ........... . ........... . ........... .. ........................ . ....... . .. .... ......... .. ...... 5

2.0 H E D RECOMMENDATI O NS

....................... . ............................. .. ................................... 8

2.1 Data Deficienci es/Co nditi o n s of Re g i stra tion

.... .. ..... .. .... ... .......................... ....... .. . 8

2.2

2.2.1

2.2.2

2.2.3

2.2.4

2.3 To l e r a nc e Co n si derati o n s

.... . ........ . ... . ........ . ... . ... . .. . ... . ... . ........................ . ...... . .. . .. . ... . 8

E nforcement A n a l yt ical Me thod

.............. ..... ........ . .. ..... .......... .. .... .......................... 8

Int e rnational Harmoniz a ti o n

...... .. .. .. ...... .. .......... .. ............................ .... ...... .. .. . .. ...... 8

Recommend ed To l erances

................................................................................. ....... 8

R ev i s ion s to Petitioned-For Tolerances

............................................ ............... ....... 9

Labe l Rec om n1 enda tion s

................................................................ ................. ........ 9

3.0 INGREDIENT PROFILE

.................................................................... . .. .. .. ..... .... .. .. ...... .... 9

3

. 1 C h e mical Id e nti ty

.. .. ........................ .. .. .. ........... . ................................ ............ .. .... ..... 9

3.2 P h ysical/C h e mi ca l C har acte ri s tic s

... .. ..................................................... .......... . .. 10

3.3 Pes ti c ide Use P a tt e rn

.............. .... ..... .............................................................. . .. . .... 10

3.3.1 Registered Products

....................................................................... ............... . .. ....... 11

3.3.2 Proposed Ne ' v Uses

............................................................................................... .. 11

3.4 A n t icipat ed Ex p os ure Path,vays

... ........... .......... ...... ..... .. ....... ... .. .. ...... . ......... ...... . . 11

3.5 Co n s ideration s of Environmental Ju s tic e

.. .. ... . ......... .. ... .. .................. ...... ..... ..... .. 11

4.0 HAZARD CHARACTE RI ZAT IO N / ASSESSMENT

.......... .. ............ .. .. ....................... 12

4. 1 Toxicology S tudi es Available for A n a l ys i s

.. ................ .................. ..... .... .. .. .......... 12

4.2 Absor p tio n
, Di s' tribution ; Metabo li s m and E x c r etio n

...................... .. ................ 13

4

. 3 Toxicological E ff ects

......................................................... . .......... .. .. ............ . .. .. . .... 14

4.4 Safety F act o r for Infant s a nd C hild re n (F QP A Sa fe ty Facto r )

......................... 1 5

4.4.1

4.4.2

4.4.3

4.4.4

4.5

4.5.1

4.5 .2

4.5.3 Co mplet e ne ss of the Toxico l ogy D ata ba se

.................. .... .. .. ... ............................... 16

Ev id e nce of Ne ur otoxicity

............................................. .. . .. ..... .. ..... ...... . ......... ........ 16

Ev id e nce of Sens iti v i ty/S u sce ptibility in the D eve l oping or Yo un g Anima l

...... 16

Residua l Unce rt a inty in the Ex posure Databa se

................................................ .. 16

Toxicity E ndp o int an d Point of Dep art ur e

...... ...... ...... .. ............ .. ............ .. .......... 16

Do se -R es p o n se Assess m e nt

. .. ... .............. ... .. ... .. . ...... ............................... . ............... 16

Recommendations for C ombinin g E xp os ure Route s

....................... .......... .. ... ..... 1 7

C l ass ific at i o n o f Ca rcino ge nic Potential

..... .. .. ........ ... .. ... ...... .... . ........................... 1 8

4.5.4 S umma ry of Po int s of D epa rtur e Used in Ri sk Assessme nt

...................... .... ..... 18

5.0 DI ETARY AN D DRINKING WATER EXPOSURE AND RISK ASSESSMENT

.... 21

5.1 M e tabolite / D eg radat e Re s idu e Profil e

. ...... .. .................... ................. .. ................. 21

5.1.1 S umma ry of Pl a nt a nd Li vestock Metabo li s m St udi es

................. .. . ......... . ...... .... 21

Pa ge 2 of79Page 3 of 79

5.1.2 Comparison of Metabolic Pathways

................................ ................................ ...... 21

5.1.3 Environmental Fate and Tr ansport

................................ ................................ ...... 21

5.1.4 Residues of Concern Summary and Rationale

................................ ..................... 22

5.2 Food Residue Profile

................................ ................................ .............................. 22

5.2.1 Residues in Crops

................................ ................................ ................................ .... 22

5.3 Water Residue Profile

................................ ................................ ............................ 23

5.3.1 Estimated Drinking Water Concentration s

................................ .......................... 23

5.4.1 Acute Dietary and Drinking Water Analysis

................................ ....................... 24

5.4.2 Chronic Dietary and Drinking Water Analysis

................................ ................... 24

6.0 RESIDENTIAL EXPOSURE AND RISK ASSESSMENT

................................ .......... 25

6.1 Residential Bystander Post

- application Inhalation Exposure

........................... 2 7

6.2 Spray Drift

................................ ................................ ................................ .............. 27

7.0 AGGREGATE EXPOSURE AND RISK ASSESSMENT

................................ ............ 28

7.1 Short

- Term Aggregate Risk

................................ ................................ .................. 28

7.2 Chronic Aggregate Risk

................................ ................................ ........................ 29

8.0 CUMULATIVE RISK

................................ ................................ ................................ ...... 29

9.0 OCCU PATIONAL EXPOSURE/RISK CHARACTERIZATION

.............................. 30

9.1 Short

- Term Handler Risk

................................ ................................ .................... 30

9.1.1 Handler Exposure Scenarios

................................ ................................ .................. 30

9.1.2 Handler Exposure Data and Assumptions

................................ ........................... 30

9.1.3 Handler Exposure and Risk Estimates

................................ ................................ . 31

9.2 Post Application Exposure

................................ ................................ .................... 33

9.2.1 Occupational Post

- application Inhalation Exposure/Risk Estimates

................ 33

9.2.2 Occupational Post

- application Dermal Exposure/Risk Estimates

..................... 33

9.2.3 Restricted Entry Interval

................................ ................................ ....................... 34

10.0 REFERENCES

................................ ................................ ................................ .............. 34

APPENDICIES

................................ ................................ ................................ ........................... 36

Appendix A. Toxicology Profile and Executive Summaries

................................ .................. 36

A.1 Toxicology Data Requirements

................................ ................................ ............. 36

A.2 Toxicity Profiles

................................ ................................ ................................ ..... 37

A.3 Hazard Identification and Endpoint Selection

................................ .................... 53

A.3.1 Acute Population Adjusted Doses (aPAD)

– All Populations

............................ 53

A.3.2 Chronic Population Adjusted Dose (cPAD)

– All Populations

.......................... 53

A.3.3 Dermal Absorption

................................ ................................ ................................ 53Page 4 of 79

A.3.4 Adult Oral Exposure (Short

- Term)

................................ ................................ ..... 54

A.3. 5 Dermal Exposure (Short

- Term)

................................ ................................ ........... 54

A.3.6 Inhalation Exposure (Short

- Term)

................................ ................................ ...... 54

A.4 Executive Summaries for Supporting Toxicity Stud ies

................................ ...... 55

A.4.1 Subchronic Toxicity

................................ ................................ ............................... 55

A.4.2 P renatal Developmental Toxicity

................................ ................................ ......... 63

A.4.3 Reproductive Toxicity

................................ ................................ ........................... 66

A.4.4 Chronic Toxicity

................................ ................................ ................................ ..... 67

A.4.5 Carcinogenicity

................................ ................................ ................................ ...... 68

A.4.6 Mutagenicity

................................ ................................ ................................ ........... 70

A.4.7 Neurotoxicity

................................ ................................ ................................ .......... 71

A.4.8 Metabolism

................................ ................................ ................................ ............. 71

A.4.9 Immunotoxicity

................................ ................................ ................................ ...... 74

Appendix B. Physical/Chemical Properties

................................ ................................ ............. 75

Appendix C. Occupational H andler Non

- Cancer Exposure and Risk Estimate Equations 77

Appendix D. Review of Human Research

................................ ................................ ................ 79Page 5 of 79

1.0 EXECUTIVE SUMMARY

1

- Naphthaleneaceti c acid , its salts, ester, and acetamide are plant growth regulators which are collectively referred to as naphthalene acetates. They are currently registered for use on various orchard and fruit crops and ornamentals. Naphthalene acetates currently have tolerances in/on a number fruit commodities ranging from 0.05 ppm to 0.15 ppm ( 40 CFR§180.155 ) , low residues, showing low poten tial for occupational exposure. Naphthalene acetates are used to stimulate growth, delay flower induction and leaf drop, prevent preharvest fruit drop, thin fruit, and control sprout formation. Registered formulations include dust, wettable powder, flowable concentrate, emulsifiable concentrate, soluble concentrate, and liquid ready

- to

- use. Thinning and stop drop

formulations cont aining naphthalene acet ates are applied using ground spray or aerial equipment. Formulations for control of sprout formation containing the ester and/or acetamide of 1

- naphthaleneacetic acid are applied by hand held sprayer and paint brush. Naphthalene acetate containing products used to stimulate root growth are applied as a d ilute root dip or soil drench. Residential uses are limited to root dip and sprout inhibition applications on ornamental plants. The plant growth regulating activity of naphthalen e acetates is due to structural similarity to the natural plant hormone indole acetic acid (IAA), the most co mmon naturally occurring auxin. IAA promotes growth in excised plant organs, induces adventitious roots, inhibits axillary bud growth, and regulate s gravitropism.

This assessment provides information to support the Section 3 registration and establishment of a

tolerance for a proposed new use of 1

- Napthalenea cetic acid , ethyl ester on pomegranate

. The product, TRE

- HOLD Sprout Inhibitor A112 (EPA R eg. No. 5481

- 429; 15.1 % NAA ethyl ester (1 lb ae/ gal)), will be used as a directed spray to the lower tree trunk and immediate surrounding area to treat the basal trunk sprouts and root suckers

. E xposure patterns for the new use on pomegranate are simila r to those as sessed for avocado, mango and mamey sapote in the most recent naphthalene acetat e risk assessment (D404398, S. Hummel, 1/16/13)

. Dietary (food and water) and occupational exposures via dermal and inhalation pathways are expected for the

propos ed new use

. There are no residential uses on pomegranate and no uses resulting in exposure to children via incidental oral activities. The label for the new use include the default REI of 12 hours, and require the following PPE for direct mixers, loaders, applicators and other handlers: long

- sleeved shirt and long pants, shoes plus socks, and chemical

- resistant gloves. Additionally, u nder PP# 4 E 8310 , the Interregional Research Project Number 4 (IR

- 4) submitted a petition for the establishment of permanent to lerances for 1

- Naphthaleneacetic acid residues on pomegranate.

Naphthaleneacetamide (NAA acetami de), naphthaleneacetic acid , potassium naphthaleneacetate ( NAA potassium salt ), ammonium naphthaleneacetate ( ammonium NAA), sodium naphthaleneacetate ( NAA sod ium salt ), and ethyl naphthaleneacetate ( NAA ethyl ester ) are assessed as a single group ( the naphthalene acetates, hereafter referred to as NAA ) because th ey are structurally related, are metabolized to the acid form

, and are eliminated from the body as

g lycine and glucuronic acid conjugates within 48 hours after exposure ( Branagan et al. 1981 )

. The toxicology data base is adequate to characterize the toxicit y of the naphthalene acetates with the exception of an inhalation study which is a data gap

. Naphth alene acetates have low acute toxicity via the oral, inhalation an d dermal routes of exposure. NAA is not a skin ir ritant or a

dermal sensitizer. Eye irritation was severe in animals exposed to naphthaleneacetic acid andPage 6 of 79

NAA sodium salt products while expo sure to NAA ethyl ester and NAA acetamide led to mild,

transient irritation

. In general, NAA sodium salt was the most toxic form in sub chronic and

chronic studies. Repeated dose exposure in oral toxicity studies resulted in decreased body weights and body weight gains accompanied by decreased food consumption. The major target organs of subchronic and chronic oral exposure wer e the liver, stomach

, and lung. Others symptoms of toxicity from oral exposure included decr eased hematocrit and hemoglobin,

reduced RBC count in rats and dogs

, and hypocellulari ty of the bone marrow in dogs. In contrast to oral exposures, NAA ethyl ester was the most toxic chemical species when administered dermally inducing epidermal hyperplasia and hyperkeratosis, sebaceous gland hyp erplasia, and dermal inflammation. The NAA sodium salt required a 10

- fold higher dose to elicit similar dermal effects and no dermal effects were noted in the NAA acetamide exposure. Systemic toxicity was not a consequence of dermal exposure to any of the tested naphthalene acetates. Developmental and offspring toxicity was linked to NAA sodium salt exposure but was not a

common observation for the entire naphthalene acetate group

. Developing rats exhibited decreased fetal weight and minor skeletal changes and were more susceptible to NAA sodium salt toxicity than the parent

. Skeletal defects and variants were observed in rabbit fetuses after exposure to NAA sodium salt in the developmental rabbit study; however, these effects only

occurred at doses that als o compromised maternal health. Offspring toxicity from NAA sodium salt manifested as reduced litter survival and pup weight throughout lactation in two generations. These effects coincided with reduced body weight in both parental generations indicating th e adults and their young were equally susceptible to NAA sodium salt. Carcinogen i city studies of

NAA acetamide in mice and NAA sodium salt in rats and mice were considered adequate for the evaluation of the oncogenicity of the NAA group. In these three st udies the tested NAA compounds were not carcinogenic in mice or rats.

Toxicological endpoints were selected for dietary/drinking water

, adult incidental oral, and inhalation exposures to oc cupational applicators

. Previously, dermal exposure was assessed for both occupational and residential uses ( D404398, S. Hummel, 1/16/13) . Updated dermal studies reflecting current HED policy indicated no concern for systemic toxicity from d ermal exposure up to 1000 mg/kg/day for any of the naphthalene acetates tested ( NAA sodium salt, NAA, and NAA acetamide); therefore a dermal assessment was not conducted in this risk assessment. There were no toxicological effects attributable to a single exposure of naphthalene acetates

observe d in oral toxi city studies; t herefore, a point of departure ( PO D ) for acute dietary exposure

was not selected. A chronic reference dose (cRfD) of 0.2 5 mg/kg/day was calculated using the highest NOAEL ( 2 5 mg/kg/day ) from two co

- critical dog studies and uncertainty factors for interspecies (10x) a nd intraspecies extrapolation (10x). The NOAEL was based on lesions of the GI tract (ulcerative duodenitis and acute or erosive gastritis) and hypocellularity of the bone marrow at 150 mg/kg/day in the subchronic dog study and was protective of the stomach lesions (slight to moderate necrosis of fundus and pyloric epithelium)

, and slight sinusoidal histiocytosis

in the liver of males observed at 75 mg/kg/day in the chronic dog study

. The FQPA SF was

reduced to 1x because the toxicology and exposure database was adequate to a ddress susceptibility in infants and small children , and the selected POD was protective of developmental and offspring effects observed at higher doses

. As a result, t he chronic population adjusted dose (cPAD) was equivalent to the cRfD

. The NOAEL (25 mg/kg/day) from the co

critical dog studies was also selected as the POD for short

- term oral exposure in adults and for inhalation exposure in occupational and residential settings

. The endpoints for the co

- critical dogPage 7 of 79

studies were protecti ve of developmental and offspring effects manifesting from these routes of exposure as well

. The short

- term adult oral endpoint was selected exclusively for the residential
aggregate assessment. An uncertainty factor of 100X (10x for interspecies extrapola tion, 10x for intraspecies variation) was applied to all endpoints selected for exposure routes and a n additional

10x database uncertainty factor (UF DB ) was applied to the inhalation endpoint to account for the

lack of an inhalation study

.

Risk assessmen ts were conducted for chronic dietary (food and water) and occupational exposure pathways based on registered uses and requests for a new use on pomegranate. D ietary (food and drinking water) exposure and risk estimates were below HED’s level of concern fo r the general population and all population subgroups (< 25% of cPAD). Likewise, o ccupational risk estimates indicate that occupational handler exposures are not of concern at the maximum proposed application rate for the new use. Post

- application occupati onal exposures are not expected based
on use patterns. Residential exposures are not expected based on the newly proposed use on pomegranate; however, existing residential uses previously re

- evaluated (D404398, S. Hummel, 1/16/13; to reflect updates to HED ’s 2012 Residential SOPs 1 along with policy changes for body weight assumptions) were updated in this memo based on new toxicological data

. Revised risk

estimates for all residential uses and aggregate risk estimates combining short

- term inhalation

and ora l exposure were not of concern to HED

.

This risk assessment relies in part on data from studies in which adult human subjects were intentionally exposed to a pesticide or other chemical. These data, which include studies from PHED 1.1; the AHETF database ; the Outdoor Residential Exposure Task Force (ORETF) database; the ARTF database; the Residential SOPs for Handlers for Paints and Preservatives are (1) subject to ethics review pursuant to 40 CFR 26, (2) have received that review, and (3) are compliant w ith applicable ethics requirements. For certain studies, the ethics review may have included review by the Human Studies Review Board. Descriptions of data sources, as well as guidance on their use, can be found at the Agency website 2

.

Tolerance Recom mendation

Pending submission of analytical standards, there are no residue chemistry issues that would preclude granting a Section 3 registration for the requested new use of NAA, n or establishment of the following tolerance for residues of NAA

.

Pomegr anate

..... ................................ ................................ ....... 0.05 ppm

Tolerances are established under 40CFR§180.155(a) for the residues of 1

- naphthaleneacetic acid, including its metabolites and degradates in or on the commodities. Compliance with the tolerance levels specified is to be determined by mea suring only 1

- naphthaleneacetic acid and its conjug ates, calculated as the s toichiometric equivalent of 1

- naphthaleneacetic acid, in or on the

1 Available: http://www.epa.gov/pesticides/science/residential

- ex posure

- sop.html

2 http://www.epa.gov/pesticides/science/handler

- exposure

- data.html and

htt p://www.epa.gov/pesticides/science/post

- app

- exposure

- data.htmlPage 8 of 79

commodity. The established tolerances range from 0.05 ppm to 2.0 ppm. The tolerance expression is in accord with the Agency’s current guidance on tolerance expressions.

The risk assessment process considers the human health effects of pesticides and incorporates a n assessment of tolerances (pesticide residue limits in food) to ensure that they meet the safety

stand ard established by the Food Quality Protection Act (FQPA) of 1996.

2.0 HED RECOMMENDATIONS

HED recommend s the registration and propose d tolerances for the use of NAA on pomegranate be granted . Additional data requirements are outlined in section 2.1, spe cific tolerance recommendations in 2.2, and label modifications in section 2.3.

2.1 Data Deficiencies/Conditions of Registration

Pending submission of analytical standards, t here are no residue chemistry issues that would preclude granting registration for the requested use of NAA on pomegranate

.

Immunotoxicity and acute and subchronic neurotoxicity studies were required as part of new 40 CFR Part 158 data requirements for registration of a pesticide. However, the Hazard and Science Policy Council ( HA S POC ) has waived the requirement for each at the present time (TXR 0056465 and 0056968)

. A 28

- day inhalation study is required and in the absence of this study, a 10x database uncertainty factor (UF DB ) was applied to the appropriate endpoints (TXR

0056465 )

.

2.2 Tolerance Considerations

2.2.1 Enforcement Analytical Method

An HPLC method using fluorescence detection (Method NAA

- AM

- 001) for apples and pea r s and a similar method for olives and olive oil (Method NAA

- AM

- 002) has been previously

submitted fo r determination of NAA in plant commodities. These methods include extraction with water and incorporate a basic hydrolysis step to release bound residues. These methods do not use benzene or diazomethane which are being discouraged by the Agency for safe ty reasons. These methods have been subjected to successful independent laboratory validations. Acceptable recoveries were obtained from apples, olives and olive oil fortified with NAA at the method LOQ (0.01 ppm) and at 1.0 ppm. This method is suitable f or enforcement.

2.2.2 International Harmonization

No Codex, Canadian, or Mexican maximum residue limits (MRLs) have been established for

residues of 1

- n aphthaleneacetic acid , it s salts, ester, and acetamide on pomegranate

.

2.2.3 Recommended Tolerances

There are no residue chemistry issues that would preclude granting registration for the requestedPage 9 of 79

new use of NAA on pomegranate or establishment of a tolerance for the combined residues of 1

- naphthaleneacetic acid and its conjugates calculated as 1

- napht haleneacetic acid from the application of 1

- naphthaleneacetic acid, its ammonium, sodium, or potassium salts, ethyl ester,

and acetamide in/on the following commodities

.

Table 2.2.3. Tolerance Summary for NAA

Commodity Established/Proposed Tolerance ( ppm) Recommended

Tolerance (ppm) Comments; Correct Commodity

Definition

Tolerances Proposed Under PP# 4 E 8310

Pomegranate 0.05 0.05

2.2.4 Revisions to Petitioned

- For Tolerances

No revisions to petitioned

- for tolerances are required.

2.3 Label Recomme ndations

No l abel r ecommendations are required.

3 .0 INGREDIENT PROFILE

3.1 Chemical Identity

The nomenclature for NAAs is provided in Table 3.1

.

Table 3.1 . NAA Nomenclature

Chemical structure

Common name NAA acetamide NAA

Molecular Formula C 12 H 11 NO C 12 H 10 O 2
Molecular Weight 185.23 186.20

IUPAC name 2

- (1

- naphthyl)acetamide 2

- (1

- naphthyl)acetic acid

CAS name 1

- naphthaleneacetamide 1

- naphthaleneacetic acid

CAS # 86

- 86

- 2 86

- 87

- 3

PC Code 056001 056002Page 10 of 79

Table 3.1 . NAA Nomenclature

Chemical structure

Common name NAA potassium salt NAA ammonium salt

Molecular Formula C 12 H 10 O 2 K C 12 H 13 NO 2
Molecular Weight 224.31 203.24

IUPAC name potassium

- 2(1naphthyl)acetate ammonium

- 2(1naphthyl)acetate

CAS name 1

- naphthalnene acetic acid, potassium salt 1

- naphthaleneacetic acid , ammonium salt

CAS # 15165

- 79

- 4 25545

- 89

- 5

PC Code 056003 056004

Chemical structure

Common name NAA sodium salt NAA ethyl ester

Molecular Formula C 12 H 10 O 2 Na C 14 H 14 O 2
Molecular Weight 208.2 214.26

IUPAC name sodium

- 2(1naphthyl)acetate ethyl

- 2( 1naphthyl)acetate

CAS name 1

- Naphthaleneacetic acid, sodium salt 1

- Naphthaleneacetic acid, ethyl ester

CAS # 61

- 31

- 4 2122

- 70

- 5

PC Code 056007 056008

3.2 Physical/Chemical Characteristics

A detailed description of the phys icochemical properties of th e naphthalene acetates are provided in Appendix C. Based on the limited available data

, 1

- naphthaleneacetic acid and its

ester exhibit relatively low or no solubility in water and higher solubility in organic solvents

whereas the sodium salt is highly so luble in water and insoluble in organic solutions

. 1

- N aphthaleneacetic acid has a relatively high vapor pressure (0.3 mmHg) , but its salts and esters have lower vapor pressures

. 1

- Naphthaleneacetic acid is relatively mobile but short lived in

terrestrial a nd aquatic environments. 1

- Naphthaleneacetic acid do not present significant

concerns for bioaccumulation based on measured bioconcentration factors.

3.3 Pesticide Use PatternPage 11 of 79

3.3.1 Registered Products

There are 44 active registrations for naphthalen e acetates

, 3 1 Section 3s

, 12 SLNs (24(c)s).

, and

1 Section 18.

3.3.2 Proposed New Uses

Under PP# 4 E 8310 , The Interregional Research Project Number 4 (IR

- 4) has submitted a petition for the establishment of permanent tolerances for residues of the plan t growth regulato r 1

- naphthaleneacetic acid in conjunction with requests for amended Section 3 registration for TRE

HOLD Sprou t Inhibitor A112

. The use pattern for the proposed new use is provided in Table

3. 3 .2

.

Table 3.3.2. Summary of Directions for U se of NAA

Applic. Timing, Type, and Equip. Formulation Applic. Rate (lb ae/gal) Max. No.

Applic. per

Season Max.

Seasonal Applic. Rate (lb ae/gal) PHI

(days)

Pomegranate

Directed spray

to the lower

tree trunks TRE

- Hold Sprout Inhibitor

A

- 112, EPA Reg . No. 5481

- 429; 15.1 % NAA, ethyl ester (1 lb

ae/gal) 0.078 lb ae/gal

10 oz. product/gallon (1% w/v) two per

year implied 0.156 45 days

Use Directions and Limitations: Treat early before suckers attain 12” in length. Best results are

attained when first treatment is made after the trees resume growth and suckers become visible.

A minimum 60

- day RTI is specified. The REI is 12 hours. Aerial application is prohibited.

Note: application rates are given in terms of acid equivalents (lb ae/A or gal ) rather than active ingredient (lb ai/A or gal) to provide the amount of NAA applied.

Label direct mixers, loaders, applicators and other handlers to wear long

- sleeved shirt and long pants, shoes plus socks, and chemical

- resistant gloves.

3.4 Anticipa ted Exposure Pathways

Dietary (food and water) and occupational exposures via dermal and inhalation pathways are expected based on the proposed use of NAA on pomegranate

. There are no post

- application

exposure s anticipated for workers re

- entering treated fields. There are no residential uses for NAA on pomegranate ; however, exposure to residential handlers is expected from currently registered uses

. This risk assessment considers all of the aforementioned exposure pathways

based on the proposed new uses of the NAA , but also considers existing uses as well, particularly

for the aggregate assessment.

3.5 Considerations of Environmental Justice

Potential areas of environmental justice concerns, to the extent possible, were considered in thisPage 12 of 79

human health ris k assessment, in accordance with U.S. Executive Order 12898, "Federal Actions to Address Environmental Justice in Minority Populations and Low

- Income Populations," ( http://ep a.gov/compliance/ej/resources/policy/exec_order_12898.pdf ). As a part of every pesticide risk assessment, OPP considers a large variety of consumer subgroups according t o well

- established procedures. In line with OPP policy, HED estimates risks to populat ion subgroups from pesticide exposures that are based on patterns of that subgroup’s food and water consumption, and activities in and around the home that involve pesticide use in a residential setting. Extensive data on food consumption patterns are com piled by the U.S. Department of Agriculture’s (USDA’s) National Health and Nutrition Examination Survey/What We Eat in America, (NHANES/WWEIA), are used in pesticide risk assessments for all registered food uses of a pesticide. These data are analyzed and categorized by subgroups based on age, season of the year, ethnic group, and region of the country. Additionally, OPP is able to assess dietary exposure to smaller, specialized subgroups and exposure assessments are performed when

conditions or circumstanc es warrant. Whenever appropriate, non

- dietary exposures based on home use of pesticide products and associated risks for adult applicators and for toddlers, youths, and adults entering or playing on treated areas post

- application are evaluated. Further

con siderations are currently in development as OPP has committed resources and expertise to the development of specialized software and models that consider exposure to bystanders and farm workers as well as lifestyle and traditional dietary patterns among sp ecific subgroups.

4.0 HAZARD CHARACTERIZATION/ASSESSMENT

4.1 Toxicology Studies Available for Analysis

Based on structural activity relationship and metabolism data, all members of the naphthalene

acetate (NAA) group are expected to exhibit s imilar toxi cological effects; t herefore

, the Agency concluded that required toxicity testing on any form should serve for all members of this group

of chemicals. T he toxicity database for NAA is sufficient for a full hazard evaluation and is considered adequate to ev aluate risks to infants and c hildren (Appendix A)

. The following

studies were considered when setting the points of departure (P O Ds) for each exposure scenario:

- 90 day oral toxicity study

– rat and dog

- 21 day dermal toxicity study

– rabbit

- Prenatal devel opmental toxicity study

– rat and rabbit

- Multi

- generation reproduction and fertility toxicity study

– rat

- 2 year chronic toxicity study

– mouse and dog

- 2 year chronic toxicity/carcinogenicity study

– rat

- Mutagenicity battery

- Metabolism pharmacokinetics s tudy

– rat

A route specific study is not available for the inhalation assessment necessitating use of a proxy oral study

. HASPOC concluded a sub chronic inhalation study is required for future naphthalene risk assessments based on a weight of evidence (WO E) approach including: 1) the physical/chemical properties and relatively high volatility of 1

- naphthaleneacetic acid (0.3 mm Hg at 26oC); 2) the potential for portal o f entry effects and demonstrated eye irritation in the acute toxicity studies; and 3 ) th at the MOEs for some occupational handler scenarios are ofPage 13 of 79

concern (MOE < 100) and do not meet the waiver criteria (MOE > 1,000 ). A 10x database uncertainty factor (UF DB ) is incorporated into inhalation assessments until this requirement is

fulfilled ( TXR 0056465, K. Rury, October 16, 2012 ).

An immunotoxicity study is required as a part of new data requirements in the 40 CFR Part 158

for conven tional pesticide registration. However, HAPOC recommended waiving the immunotoxicity study for naphthalene acetat es ( TXR 0056968

, J. Leshin, May 21, 2014 ) . The decision was supported by WOE approach that incorporated the following considerations : 1) the toxicology database for of naphthalene acetates does not reveal any evidence of treatment

- related

effects on the im mune system suggesting that the immune system is not the primary target organ;

and 2) an immunotoxicity study is not a nticipated to provide a lower P O D or result in a more sensitive endpoint than those already used for the naphthalene acetates risk assessm ent.

Acute and subchronic neurotoxicity studies are also required as a part of new data requirements in the 40 CFR Part 158 for conventional pesticide registration. However, HASPOC concluded,

based on WOE approach, that acute and sub chronic neurotoxicity studies are not required at this

time ( TXR 0056465, K. Rury, October 16, 2012 ) . This approach included the following considerations: 1) the lack of neurotoxicity in the available toxicology studies for NAA; 2) liver, stomach, and lung are the target orga ns with dogs being the most sensitive species; 4) because the dogs are the most sensitive species, neurotoxicity studies conducted in rats would not provide a more sensitive endpoint for risk assessment; and 5) studi es would be unlikely to yield PODs

lower than the current PO Ds used for overall risk assessment.

4.2 Absorption, Distribution, Metabolism and Excretion

The absorption, distribution metabolism and excretio n of NAA were studied in rats. In one study, rats were given either a single 1 or 100 mg /kg bw oral dose, or a 14

- day repeated dose (1 mg/kg/day) of [ 14 C] ring labeled NAA acetamide

. NAA acetamide was readily absorbed and

excreted within 36 hours . R ecovery of administered radioactivity was 97

- 101%. Urinary

excretion accounted for 66

- 74% of t he administered radioactivity for single and repeat doses. Repeat doses did not appreciably affect the absorption/excretion processes. Excretion via the feces accounted for the remainder of the administered radioactivity in all treatment groups. Urinary metabolites revealed amide cleavage followed by glycine conjugation with the glycine conjugate being the major metabolite of the low and repeat doses (14

- 47%). The glucuronide conjugate was also a major metabolite at the low doses (4.5

- 7%). For feces, th e major metabolite detected was the dihydrodiol of NAA acetamide (4

- 11%). Parent compound was detected at low concentrations (1

- 2% of administered) only in feces.

In another study, rats were given either a single 1 or 100 mg/kg bw oral dose, or a 14

- da y repeated dose (1 mg/kg/day) of [ 14 C] ring labeled NAA ethyl ester. Recovery of administered radioactivity was 99

- 101%. NAA ethyl ester was readily absorbed and excreted w ithin 36

- 48 hours following single and repeat doses. Urinary excretion accounted f or 68

- 85% of the administered radioactivity following single or multiple oral low doses and 62

- 78% following a single high dose. Excretion via the feces accounted for the remainder of the administered radioactivity excreted by all treatment groups. At the high dose, glucuronide conjugation appeared to play a more important role following ester cleavage. Parent compound was detectedPage 14 of 79

at low concentrations (0.5

- 5% of administered) only in feces. For both studies, excretory patterns exhibited no gender

- relat ed variability for the low dose groups and only minor gender difference at the high dose. Excretion patterns of the high

- dose group reflected delayed absorption. Tissue burdens of parent and metabolites were very low at termination for both

studies. Mos t components in the matrices examined (urine and feces) were adequately quantified

and characterized.

The metabolism studies of the acid and its acetamide and the ethyl ester in animals provide supporting evidence that the toxicity of the naphthalene ac etates would be similar since all are metabolized to the acid form and eliminated from the body as glycine and glucuronic acid conjugates within 36 to 48 hours of initial exposure.

4.3 Toxicological Effects

1

- Naphthaleneacetic acid , its salts, ester, and acetamide are plant growth regulators which are collectively referred to as naphthalene acetates. Its structure mimics the endogenous plant hormone indole acetic acid (IAA), a natural auxin that promotes growth in excised plant organs,

induces adventitiou s roots, inhibits axillary bud growth, and regulates gravitropism. In general where comparisons were feasible, the sodium salt form was more toxic than the other

NAA members. Nevertheless, target organs and type of effects were consistent across all

memb ers despite disparity in onset and severity

.

The commonalities across the na phthalene acetate family wa s attributed to a share d ADME pathway. Ingested naphthalene ace tates were readily absorbed, metabolized extensively (0.5

- 5% parent compound in excreta) , and eliminated efficiently within 36

- 48 h ou rs minimizing tissue accumulation. As a result, organ specific and systemic toxicity from oral exposure did not intensify with duration. Liver metabolism accounted for a portion of the excreted dose (predominant ly the glucuronic acid conjugate at high and low concentration s) and was a target of

NAA toxicity in rats, mice and dogs. Hepatic insult was characterized by inflammation of the tissues around the bile duct, hepatocyte degeneration, sinusoidal histiocytosi s , and increased liver weight accompanied by elevated liver enzyme levels

, necrosis, extramedullary hematopoiesis,

and mon oculear/mixed cell infiltration

. The stomach and gastrointestinal tract were another

mammalian target of the naphthalene acetates ( nec rosis of fundus and pyloric epithelium mucosal gland dilation

, stomach irritation, ulcerative duodenitis, acute or erosive gastritis,

emesis and soft feces) despite fecal elimination accounting for a small percentage of the

administered dose

. Dogs were the most suscept ible mammal to oral subchronic and chronic

exposures exhibiting primarily liver and stomach injury

. In addition to the liver and stomach, the lungs of exposed rats (focal alveolar macrophages) and mice (lung adenomas ) were compromised though w hether these effects point to the lungs as a target organ remains equivocal. Repeated oral exposure also elicited decreased hematocrit and hemoglobin along with

reduced RBC count in ra ts and dogs

, and hypocellularity of the bone marrow of dogs. Reduced

bod y weight and body weight gain either co

- occurred with target organ toxicity or were the lone symptoms of toxicity.

Similar systemic toxicity in forms of decreased body weight/gain, and lesions in the liver,

stomach

, and lung via the oral route was not ob served in dermal exposures to 1

-Page 15 of 79

naphthaleneacetic acid , NAA acetamide, and NAA sodium salt up to a dose of 1000 mg/kg/day

. Instead d ermal toxicity manifest ed at the point of contact with the skin

. Prolonged exposure to

NAA ethyl est er , the most toxic form for dermal exposures, resulted in epidermal hyperplasia, hyperkeratosis, sebaceous gland hyper plasia and dermal inflammation. Similar dermal effects ( hyperplasia of sebaceous gland and hyperplasia and hyperkeratosis of epidermis) were observed following NA A sodium salt dermal exposure, but, unlike the oral exposures, the sodium salt form was not as toxic as the ethyl ester form. Dermal toxicity was not universal for all NAA compounds , however, as NAA acetamide exposure was not irritating up to 1000 mg/kg/da y

.

I n the rat developmental stu d y with NAA sodium salt, fetal effects (skeletal variations, decreased fetal weights) were observed in the absence of maternal toxicity

. In contrast, rabbits exhibited developmental effects (skeletal defects and variants an d a decrease in ossification of the manus)

from in utero exposure only at doses that also compromised maternal health ( reduced body weight, clinical signs and stomach irritation ). Reduced rat pup weights and reduced litter survival during lactation was als o observed in both generations of the reproduction study with NAA

sodium salt. Lower body weight in the F 1 generation persisted after switching to the contaminated diet and remained depressed through the subsequent pre

- mating, gestation and lactation perio ds. Parental body weight , body weight gain and food consumption was depressed

at the same dose which likely contributed to the reduction in offspring survival and growth. The sodium salt also induced changes to r eproductive organs in dogs but were consider ed secondary

to the systemic, liver and stomach effects. The d evelopmental and offspring toxicity observed was unique to the sodium salt.

The entire class of naphthalene acetates exhibited low acute oral (Category III), dermal (Category III), and inhalat ion toxicity (Category III/IV) and none were dermal irritants (all Category IV) or dermal sensitizers. The severity of eye irritation varied significantly across the NAA compounds. NAA and NAA sodium salt were strong eye irritants (Category I), while NAA

e thyl ester was only a mild eye ir ritant (Category IV). T he eye irritation potential of NAA

acetamide wa s equivocal. One study indicated NAA acetamide caused severe eye irritation (Category I) while a more recent study identified it as a mild irritant (Cate gory IV).

The tested naphthalene acetates did not exhibit mu ta genicity or carcinogenicity.

4.4 Safety Factor for Infants and Children (FQPA Safety Factor)

T he FQPA safety factor (FQPA SF) for infant s and childr en wa s reduced to 1x for non

inhalation routes of exposures based on the following considerations: 1) The toxicology data base for NAA is complete and adequate for assessing increased susceptibility under FQPA

. The dietary and inhalation endpoints selected fro m the co

critical dog studies (NOAEL = 25 mg/kg/day) is protective of the effects observed in the rat developmental (LOAEL = 150 mg/kg/day), rabbit developmental (LOAEL = 300 mg/kg/day) and rat reproduction (LOAEL = 210 mg/kg/day) studies

. Therefore, the

p otential for increased susceptibility in infants and children is low. 2) T here are no residual uncerta inties in the exposure database

.Page 16 of 79

3) T he dietary risk assessment is conservative using the current endpoints and will not underestimate dietary exposure to NAA.

EPA is retaining a 10X FQPA SF for inhalation exposure scenarios in all population groups to account for the lack of a route specific inhalation study.

4.4.1 Completeness of the Toxicology Database

The toxicity database for NAA is sufficient for a fu ll hazard evaluation and is considered adequate to evaluate risks to infants and children. Acceptable developmental toxicity studies in the rat and rabbit and an acceptable reproduction study in the rat are available. HASPOC did not

waive the subchronic i nhalation study and recommended use of a 10x database uncertainty factor (UF DB ) for inhalation assessments to account for the lack of a route specific study. HASPOC waived the requirement for the immunotoxicity study and neurotoxicity battery for the prese nt

assessment. HASPOC decisions are described in more detail in Section 4.1.

4.4. 2 Evidence of Neurotoxicity

There are no neurotoxicity studies available for the current assessment ; however, n o signs of neurotoxicity or neuropathology were reported in the submitted chronic and subchronic studies

. Furthermore, the literature on IAA, a compound with structural similarity to NAA, did not identify a neurotoxic mode of action

. HASPOC has determined that a cute and subchronic neurotoxicity studies are not nee ded at the present time.

4.4.3 Evidence of Sensitivity/Susceptibility in the Developing or Young Animal

T here is low concern (and no residual uncertainty) for pre

- and/or postnatal toxicity resulting from exposure to the naphthalene acetates because c lear NOAEL and LOAELs were established for the developmental and offspring effects and the POD (25 mg/kg/day) for all exposure scenarios is protective of these effects.

4.4.4 Residual Uncertainty in the Exposure Database

There are no residual uncertainties in the exposure database. The dietary risk assessment is conservative and will not underestimate dietary exposure to the naphthalene acetates

.

4.5 Toxicity Endpoint and Point of Departure

4.5.1 Dose

- Respo nse Assessment

Toxicity endpoints and PODs for dietary (food and water), occupational, and residential exposure scenarios have been updated since the last assessment and are summarized below and

in Table 4.5.4.1 and 4.5.4.2 . A detailed description of the studies used as a basis for the selected endpoints for the naphthalene acetates are presented in Appendix A.Page 17 of 79

There were no toxicological effects attributable to a single exposure of NAA observed in oral toxicity studies. Therefore, a n endpoint of conc ern was not se lected for the acute dietary

assessment . A chronic reference dose (cRfD) of 0.25 mg/kg/day was calculated using the highest NOAEL (25 mg/kg/day) from two co

- critical dog studies and uncertainty factors for interspecies ( UF A =10x ) and intraspec ies extrapolation ( UF H =10x ). The NOAEL was based on lesions of the GI tract (ulcerative duodenitis and acute or erosive gastritis) and hypocellularity of the bone marrow at 150 mg/kg/day in the subchronic dog study and was protective of the stomach lesions (slight to moderate necrosis of fundus and pyloric epithelium), and slight sinusoidal histiocytosis in the liver of males observed at 75 mg/kg/day in the chronic dog study. The higher NOAEL from the subchronic study is protective of the chronic study LOAE L since the effects and severity were similar between the two studies and there was no evidence of progression with increased exposure duration. The FQPA SF was reduced to 1x because the toxicology and exposure database was adequate to address susceptibili ty in infants and small children, and the selected POD was protective of developmental and offspring effects observed at higher doses. As a result, the chronic population adjusted dose (cPAD) is equivalent to the cRfD.

The NOAEL (25 mg/kg/day) from the co

- critical NAA sodium salt dog studies was selected as

the POD for a short

- term adult oral exposure

. This study was selected because it provided the lowest LOAEL and highest NOAEL of all the candidate studies conducted over a short duration ( < 90 days) an d it was protective of developmental and offspring effects observed at higher

doses

. The short

- term adult oral endpoint was selected exclusively for the residential aggregate

assessment. The level of concern (LOC) for the short term adult oral exposure is 100 based on

unce rtainty factors of inter species variability ( UF A =10x) and in tra species sensitivity ( UF H =10x)

.

Dermal exposure up to 1000 mg/kg/day did not result in systemic toxicity for any of the naphthalene acetates tested (NAA sodium salt, NAA, and NAA acetamide); therefore a dermal assessment was not conducted. A dermal absorption study was not submitted; however, the absence of systemic toxicity at high dose dermal exposure suggests absorption is limited. Furthermore, in several naphthalene acetat es (including NAA ethyl ester) irritation effects precede systemic effects precluding dermal exposures of > 1000 mg/kg/day (or 100 mg/kg/day in the case of the ethyl ester). The in utero susceptibility in the rat developmental study was not

used to set end points for a dermal assessment because dermal exposure is unlikely to provide the internal dose required to elicit these effects based on the low absorption potential and irritant properties of the naphthalene acetates.

In lieu of an inhalation st udy

, the NOAEL (25 mg/kg/day) from the co

- critical dog studies was adopted to assess short

- term inhalation risk

. An absorption factor of 100% was assumed for all inhalation exposures. The level of concern (LOC) for the short

- term inhalation exposure is 100 0

bas ed on uncertainty factors for interspecies variability ( UF A =10x), for in tra species sensitivity ( UF H =10x), and to account for the inhalation study omission ( UF DB =10x)

.

4.5.2 Recommendations for Combining Exposure Routes

When there are potential reside ntial exposures to the pesticide, the aggregate risk assessment must consider exposures from three major sources: oral, dermal and i nhalation exposures. If thePage 18 of 79

toxicity endpoints for dermal, oral, and inhalation routes of exposure are similar , then the

ex posure or risk estimates from these exposure routes are combined. Endpoints for short

- term oral and inhalation exposure are based on the same effects (stomach lesions and sinusoidal histiocytosis in the liver) and can be combined for risk assessment. Derma l exposure cannot be combined because a dermal assessment was not required.

4.5.3 Classification of Carcinogenic Potential

A published NCI carcinogenicity study of NAA acetamide in mice, a guideli ne chronic/oncogenicity study of NAA sodium salt in rats, and a chronic/oncogenicity study of

NAA sodium salt mice were considered adequate for the evaluation of the oncogenicity of the NAA group. In these three studies the tested NAA compounds were not c arcinogenic in mice or

rats.

4.5.4 Summary of Points of Departure Used in Risk Assessment

Toxicological doses/endpoints selected for the naphthalene acetate risk assessment are provided

in Tables 4 .5.4.1 and 4.5.4.2

.

Table 4.5.4.1. Summary of Toxicol ogical Endpoints for Naphthalene Acetates for Use in Dietary and Non

Occupational Human Health Risk Assessments

Exposure/Scenario Point of

Departure Uncertainty/FQP

A Safety Factors RfD, PAD,

LOC for Risk

Assessment Study and Toxicological Effects 1

Ac ute Dietary (General Population) An acute RfD for the general population or any population subgroups was not selected because no

effect attributable to a single day oral exposure was observed in animal studies.

Chronic Dietary (All Populations) NOAEL=

2 5 mg/kg/day UF A = 10x

UF H =10 x FQPA SF= 1 x Chronic RfD =

0.2 5 mg/kg/day

cPAD = 0.2 5 mg/kg/day Co

- critical Dog Studies with NAA Na salt:

Subchronic Toxicity (MRID 42983801)
Chronic Toxicity (MRID 43744201)

Subchronic LOAEL = 150 mg/kg/day based

on GI tract l esions and hypocellularity of the

bone marrow
Subchronic NOAEL= 25 mg/kg/day

Chronic LOAEL = 75 mg/kg/day based on

stomach lesions in 75% of the males and slight sinusoidal histiocytosis in the liver of

50% of the males Chronic NOAEL = 15 mg/kg/dayPage 19 of 79

Point of Departure (P O D) = A data point or an estimated point that is derived from observed dose

- response data and

used to mark the beginning of extrapolation to determine risk associated with lower environmentally relevant human exposures. NOAEL = no observed adverse effect level. LOAEL = lowest observed adverse effect level. UF = uncertainty factor. UF A = extrapolation f rom animal to human (interspecies). UF H = potential variation in sensitivity among members of the human population (intraspecies). FQPA SF = FQPA Safety Factor. PAD = population adjusted dose (c = chronic). RfD = reference dose.

1 The NOAEL/LOAEL used to set endpoints for the co

- critical dog studies are in bold

2 Inhalation absorption is assumed to be equivalent to oral absorption

3 FQPA SF for inhalation accounts for the lack of an inhalation study. Adul t Oral

Sho r t

- term (1

- 30 Days) NOAEL=

25 mg/kg/day UF A = 10x

UF H =10 x FQPA SF= 1 x LOC = 100 Co

- critical Dog Studies with NAA Na salt:
Subchronic Toxicity (MRID 42983801)
Chronic Toxicity (MRID 43744201)

Subchronic LOAEL = 150 mg/kg/day based

on GI tract le sions and hypocellularity of the

bone marrow
Subchronic NOAEL= 25 mg/kg/day

Chronic LOAEL = 75 mg/kg/day based on

stomach lesions in 75% of the males and slight sinusoidal histiocytosis in the liver of

50% of the males Chronic NOAEL = 15 mg/kg/day

Incid ental Oral

All Durations Incidental oral exposures are not anticipated for currently registered uses and the proposed use on

pomegranate.

Dermal

All Durations Dermal exposure up to the limit dose (1000 mg/kg/day) did not result in systemic toxicity for a ny of

the naphthalene acetates tested (NAA sodium salt, NAA, and NAA acetamide); therefore, a dermal

assessment was not conducted.

Inhalation

Short

- Term (1

- 30 days) NOAEL=

25 mg/kg/day 2 UF A = 10 x

UF H = 10 x FQPA SF = 10x 3 LOC = 1000 Co

- critical Dog Studies with NAA Na salt:
Subchronic Toxicity (MRID 42983801)
Chronic Toxicity (MRID 43744201)

Subchronic LOAEL = 150 mg/kg/day based on GI tract lesions and hypocellularity of the

bone marrow
Subchronic NOAEL= 25 mg/kg/day

Chronic LOAEL = 75 mg/kg/day b ased on

stomach lesions in 75% of the males and slight sinusoidal histiocytosis in the liver of

50% of the males Chronic NOAEL = 15 mg/kg/day

Inhalation

Intermediate and Long

- term Intermediate and long

- term inhalation exposures are not anticipated for cu rrently registered uses and

the proposed use on pomegranate

.

Cancer Bioassay in rats and mice not carcinogenic. Not mutagenic.Page 20 of 79

Table 4.5.4.2. Endpoints selected for Assessing Occupa tional Risks for Naphthalene Acetates

Exposure

Scenario 1 Dose Used in Risk

Assessment, UF Uncertainty/FQPA

Safety Factors RfD, PAD, LOC

for Risk

Assessment Study and Toxicological Effects 1

Dermal Short, Intermediate, and Long

- term Dermal exposure up t o the limit dose (1000 mg/kg/day) did not result in systemic toxicity for any of the

naphthalene acetates tested (NAA sodium salt, NAA, and NAA acetamide); therefore, a dermal assessment

was not conducted.

Inhalation

Short

- Term (1

- 30 days) NOAEL= 25

mg/kg/day 2 UF A = 10 x

UF H = 10 x UF DB = 10 x LOC = 1000 Co

- critical Dog Studies with NAA Na salt:
Subchronic Toxicity (MRID 42983801)
Chronic Toxicity (MRID 43744201)

Subchronic LOAEL = 150 mg/kg/day based on GI tract lesions and hypocellularity of

the bon e marrow Subchronic NOAEL= 25 mg/kg/day

Chronic LOAEL = 75 mg/kg/day based on

stomach lesions in 75% of the males and slight sinusoidal histiocytosis in the liver of

50% of the males Chronic NOAEL = 15 mg/kg/day

Inhalation

Intermediate and Long

- term Int ermediate and long

- term inhalation exposures are not anticipated for currently registered uses and the

proposed use on pomegranate.

Cancer Bioassay in rats and mice not carcinogenic. Not mutagenic.

Point of Departure (P O D) = A data point or an estimat ed point that is derived from observed dose

- response data and used to mark the beginning of extrapolation to determine risk associated with lower environmentally relevant human exposures. NOAEL = no observed adverse effect level. LOAEL = lowest observed adverse effect level. UF = uncertainty factor. UF A = extrapolation from animal to human (interspecies). UF H = potential variation in sensitivity among members of the human population (intraspecies). UF DB = database uncertainty factor: lack of an

inhala tion specific study. LOC = level of concern.

1 The NOAEL/LOAEL used to set endpoints for the co

- critical dog studies are in bold

2 Inhalation absorption is assumed to be equivalent to oral absorptionPage 21 of 79

5.0 DIETARY AND DRINKING WATER EXPOSURE AND RISK ASSES SMENT

5.1 Metabolite/Degradate Residue Profile

5.1.1 Summary of Plant and Livestock Metabolism Studies

The qualitative nature of the residue in plants and ruminants resulting from registered uses of naphthalene acetates is adequately understood based on apple, olive, and goat metabolism studies. Based on guideline requirements, plant metabolism studies should be conducted for a minimum of three diverse crops to determine the qualitative metabolic fate of the active ingredient (OPPTS GLN 860.1300). Al though metabolism data are not available to a commodity similar to potatoes, a 3 rd diverse metabolism study was not required

. However, if other uses are proposed on crops other than fruit crops, tree nuts, or fruiting vegetables or at a higher application rate on potatoes, a metabolism study (preferably on a root crop) will be

needed.

5.1.2 Comparison of Metabolic Pathways

In a rat metabolism stud ies with ring labeled NAA acetamide and ring labeled NAA ethyl ester, glucuronide conjugation was seen fol lowing ester cleavage. Parent compound was detected at low concentrations (0.5

- 5% of administered) only in feces. The rat met abolism studies of the acid, its acetamide and the ethyl ester provide supporting evidence that the toxicity of these

various for ms of NAA would be similar since all are metabolized to the acid form and eliminated from the body as glycine and glucuronic acid conjugates within 36 to 48 hours of initial

exposure.

Similar results have been seen in goat metabolism stud ies and in apple and olive metabolism

studies

. T he terminal residues of concern in plants and ruminants are the parent compounds, 1

- naphthaleneacetic acid, and its conjugates

. T he qualitative nature of the residues in orchard tre es is adequately understood. Additional pl ant metabolism studies may be required if use is expanded beyond orchard trees.

5.1.3 Environmental Fate and Transport

1

- naphthaleneacetic acid appears to be generally short lived, based on measured and modeled values. It should degrade by means of a combination of both biotic and abiotic processes. The reported half

- life for 1

- naphthaleneacetic acid of 10 days was attributed to microbial degradation. 1

- Naphthaleneacetic acid is mostly ionized in the environment so would partition preferentially wit h the water. The environmental fate characteristics of the salts of 1

- naphthaleneacetic acid are expected to be similar to those of the acid. In the environment, the NAA salts will rapidly dissociate to 1

- naphthalene acetate anion and its corresponding c ation. Based on its pKa, 1

- naphthaleneacetic acid is expected to exist mostly as the anion in normal environmental conditions. Anions generally do not adsorb to organic carbon and clay more strongly than their neutral counterparts. Volatility may be an important route of dissipation for

1

- naphthaleneacetic acid under various environmental conditions based on 1

- naphthaleneacetic
acid’s relatively high measured and estimated vapor pressures (0.3 mmHg). NAA ethyl ester isPage 22 of 79

susceptible to hydrolysis at high pHs. The product of NAA ethyl ester hydrolysis is 1

- naphthaleneacetic acid. 1

- Naphthaleneacetic acid in aqueous solution appears to be unstable to sunlight irradiation. Upon exposure to sunlight, gaseous phase 1

- naphthaleneacetic acid reaction with hydro xyl (OH) radicals should proceed with a half

- life of around 0.3 days. 1

- Naphthaleneacetic acid is mobile to moderately mobile according to the FAO mobility

classification. For 1

- naphthaleneacetic acid measured bioconcentration factors (BCFs) of only

0.15

- 0.59 and <1.7

- 4.2 were observed in carp ( Cyprinus carpio ) at test chemical concentrations of 0.5 and 0.05 mg/L, respectively. These values suggest a low potential of bioconcentration for

1

- naphthaleneacetic acid

.

There are considerable uncertainties in t his assessment due to the lack of measured data. Most of

the environmental fate characteristics available for 1

- naphthaleneacetic acid are derived from structure activity relationships. Furthermore, there is lack of information about possible degradates of 1

- naphthaleneacetic acid

.

5.1.4 Residues of Concern Summary and Rationale

Residues of concern were determined by the HED risk assessment team for NAA. The terminal residues of concern in plants and ruminants are the parent compounds, 1

- naphthalenea cetic acid and its conjugates, based on apple, olive, and goat metabolism studies. (D293239, G. Otakie, November 18, 2003).

Table 5.1 . NAA Residues of Concern in Plants and Ruminants.

Matrix Residues of Concern

For Risk Assessment For Tolerance E xpression

Plants Primary and Rotational crops NAA and Conjugates NAA and Conjugates

Livestock Ruminant and Poultry NAA and Conjugates NAA and Conjugates

Drinking Water NAA and Conjugates n/a

n/a = not applicable

5.2 Food Residue Profile

5.2.1 Residu es in Crops

The submitted field trial data supporting new use on pomegranate are adequate. An acceptable method was used for residue quantitation, and adequate storage stability data were submitted to support sample storage durations and conditions for al l analytes. In pomegranate harvested 45 days following the last of two applications of a 15.1% EC formulation of NAA ethyl ester directed to the base of the tree as a 1% w/v ai spray to run

- off to pruned sprouts/suckers, residues

of 1

- naphthaleneacetic aci d were below the LOQ (<0.05 ppm) in/on all samples. The results

from these studies are discussed in the Residue Chemistry Chapter (DP423409, T. Morton, June 8, 2015) and the appropriate data evaluation report (DER) and summarized in Table 5.2.1

. Residue d ecline was not investigated.Page 23 of 79

Table 5.2.1 . Summary of Residues from Pomegranate Field Trials with NAA ethyl ester.

Commodity Total Rate 1

(% w/v ai solution) Analyte PHI (days) n 2 Residue Levels (ppm)

Min. 3 Max. 3 LAFT 4 HAFT 4 Median 4 Mean 4 SD

Pomegranate 2 X 1% NAA 5 45 2 <0.05 <0.05 0.05 0.05 0.05 0.05 N/A

1 T wo applications of a 1% solution were made at each trial site.

2 n = no. of independent field trials.

3 Values based on total number of samples.

4 Values based on per

- trial a verages. LAFT= lowest average field trip, HAFT = highest average field trial, SD = standard deviation. For computation of the LAFT, HAFT, median, mean, and standard deviation, values <LOQ are assumed to be at the LOQ. N/A = Not applicable.

5 Residues of NAA ethyl ester were determined by a common moiety method that converts residues of NAA acetamide and NAA ethyl ester to NAA.

5.3 Water Residue Profile

5.3. 1 Estimated Drinking Water Concentrations

Tier I Estimated Drinking Water Concentrations ( EDWCs) in surface and groundwater fo r 1

- naphthaleneacetic acid, NAA sodium salt

, NAA potassium salt, NAA ethyl ester

, and NAA

acetamide 3 were provide for use in the dietary exposure assessment . The EDWCs were calculated using the Tier 1 surface water aqua tic model FIRST and the Tier I/II groundwater

model PRZM

- GW (in Tier I mode). The Environmental Fate and Effects Division (EFED) has reviewed a proposed Interregional Research 4 (IR

- 4) and registrant petition to register the use of NAA ethyl ester for the use on pomegranate for controlling basal trunk sprouts and root suckers ( D423410, J. Melendez, May 4, 2015 ) . The maximum single application rate is 3.6 lb a.e./A 4

, with two applications allowed at 60 day intervals, for the product Tre

- Hold ® Sprout Inhibi tor A

112 (EPA Reg. No. 5481

- 429, containing 1 lb a.e./gallon) . Only g round applications are allowed on pomegranate, diluted in a large volume of water, applied to the lower tree trunks and immediate surrounding area. Previously, the maximum rate allowed was for the use on olives (single application at 0.33 lb a.e./A). Since this new use represents a higher application rate than previously calculated, and no groundwater values derived from PRZM

- GW were previously calculated, new EDWCs are hereby calculat ed and provided

.

Table 5.3.1 . Maximum Tier I Estimated Drinking Water Concentrations (EDWCs) for drinking

water assessment for all naphthalene acetates , based on ground application of NAA ethyl ester on pomegranates at 3.6 lb a.e./A x 2 applications/yea r

DRINKING WATER SOURCE (MODEL USED) SCENARIO (rate modeled per crop cycle) MAXIMUM ESTIMATED DRINKING WATER CONCENTRATION (EDWC) (ppb) Groundwater (PRZM

- GW) WI sand/7.2 lb a.e./A/yr Acute 789

3 C ollectively known as naphthalene acetates

. 4 The abbreviation a.e. refers to acid equivalents ( i.e. , the lbs of NAA ethyl ester, expressed as lbs of NAA acid).Page 24 of 79

DRINKING WATER SOURCE (MODEL USED) SCENARIO (rate modeled per crop cycle) MAXIMUM ESTIMATED DRINKING WATER CONCENTRATION (EDWC) (ppb) WI sand/7.2 lb a.e./A/yr Chronic 646

Surface water (FIR ST) Index Reservoir/7.2 lb a.e./A/yr Acute 440 Index Reservoir/7.2 lb a.e./A/yr Chronic 65.1

5

. 4 Dietary and Drinking Water Exposure and Risk

Naphthalene acetates chronic dietary exposure assessment was conducted using the Dietary Exposure Evaluation Model software with the Food Commodity Intake Database DEEM

FCIDTM, Version 3.16, which incorporates consumption data from USDA’s National Health and Nutrition Examination Survey, What We Eat in America, (NHANES/WWEIA). This dietary survey was conducted f

rom 2003 to 2008. The data are based on the reported consumption of more than 20,000 individuals over two non

- consecutive survey days. Foods “as consumed” (e.g., apple pie) are linked to EPA

- defined food commodities (e.g. apples, peeled fruit

- cooked;

f resh or N/S; baked; or wheat flour

- cooked; fresh or N/S, baked) using publicly available recipe translation files developed jointly by USDA/ARS and EPA. For chronic exposure assessment, consumption data are averaged for the entire U.S. population and wi thin population subgroups, but for acute exposure assessment are retained as individual consumption events. Based on analysis of the 2003

- 2008 WWEIA consumption data, which took into account dietary patterns and survey respondents, HED concluded that it i s most appropriate to report risk for the following population subgroups: the general U.S. population, all infants (<1 year old), children

1

- 2, children 3

- 5, children 6

- 12, youth 13

- 19, adults 20

- 49, females 13

- 49, and adults 50

- 99 years old.

For chronic dietary exposure assessment, an estimate of the residue level in each food or food

form ( e .g. , orange or orange juice) on the food commodity residue list is multiplied by the average daily consumption estimate for that food/food form. The resulting residu e consumption estimate for each food/food form is summed with the residue consumption estimates for all other food/food forms on the commodity residue list to arrive at the total average estimated exposure. Exposure is expressed in mg/kg body weight/day a nd as a percent of the cPAD. This procedure is performed for each population subgroup.

5

. 4 .1 Acute Dietary and Drinking Water Analysis

No acute dietary risk assessment was conducted. An acute RfD for the general population or any population subgroups was not selected because no effect attributable to a single day oral exposure was observed in animal studies.

5

. 4 .2 Chronic Dietary and Drinking Water Analysis

A new dietary assessment was conducted for the proposed new use. The proposed new use result s in dietary risk estimates below HED’s level of concern ( Table 5.4 )

. Infants <1 year old are t he most

hi ghly exposed subpopulation , with 15 % of the cPAD.Page 25 of 79

Table 5.4. Summary of Chronic Dietary Exposure and Risk for Napthelene Acetates

Population Su bgroup cPAD (mg/kg/day) Chronic Exposure (mg/kg/day) % cPAD General U.S. Population

0.25 0.013977 5.6 All Infants (< 1 year old) 0.036203 15

Children 1

- 2 years old 0.022367 8.9

Children 3

- 5 years old 0.018232 7.3

Children 6

- 12 years old 0.01257 5 5.0

Youth 13

- 19 years old 0.010202 4.1

Adults 20

- 49 years old 0.013738 5.5

Adults 50

- 99 years old 0.013583 5.4

Females 13

- 49 years old 0.013701 5.5

6 .0 RESIDENTIAL EXPOSURE AND RISK ASSESSMENT

Residential exposures are not expected based on the newly proposed use on pomegranate; however, existing residential uses previously re

- evaluated (D404398, S. Hummel, 1/16/13; to reflect updates to HED’s 2012 Residential SOPs 5 along with policy changes for body weight assumptions) are being updated in t his memo based on new toxicological data. Revised risk estimates for the residential uses of naphthalene acetates (Table 6.0) are not of concern to HED (MOE > 1000); however, t hese revised existing uses will impact the human health aggregate risk

assessmen t.

5 Available: http://www.epa.gov/pesticides/science/residential

- exposure

- sop.htmlPage 26 of 79 1 Based on registered or proposed label (Reg. No.5481

- 429, 5481

- 541).

2 Exposure Science Advisory Council Policy #9.1.

3 Inhalation Dose = Inh alation Unit Exposure ( μg /lb ae) x Conversion Factor (0.001 mg/ μg ) x Application Rate (lb ae/acre or gal) x Area Treated or Amount Handled (A or gallons/day) / BW (kg).

4 Inhalation MOE = Inhalation NOAEL (mg/kg/day) / Inhalation Dose (mg/kg/day). Table 6.0. Residential Handler Non

- cancer Exposure and Risk Estimates for Naphthalene Acetates

Exposure Scenario Inhalation LOC Inhalation Unit Exposure (μg/lb ae) Maximum

Application Rate 1 Area Treated or Amount Handled Daily 2 Inhalation

Dose (mg/kg/day) 3 MOE 4

Paint brush/rolling after pruning trees, or spraying near the base of the tree after pruning root suckers (Ornamentals)

Paint

- airless sprayer

1000 0.56

0.078 lb ai/1

- gal can 5 (1

- gallon can) 0.0027 9,200

Paint

- brush/roller 0.2 2 (1

- gallon can) 0.00039 64,000

Paint

- manually pressurized

handwand 0.018 3 (1

- gallon can) 0.000053 470,000Page 27 of 79

6.1 R esidential Bystander Post

- application Inhalation Exposure

Volatilization of pesticides may be a source of post

- application inhalation exposure to individuals nearby pesticide applications. The agency sought expert advice and input on issues

related to vo latilization of pesticides from its Federal Insecticide, Fungicide, and Rodenticide Act Scientific Advisory Panel (SAP) in December 2009, and received the SAP’s final report on March 2, 2010 ( http://www.epa.gov/scipoly/SAP/meetings/2009/120109meeting.html ). The agency has evaluated the SAP report and has developed a Volatilization Screening Tool and a subsequent Volatilization Screening Analysis ( http://www.regulations.gov/#!docketDetail;D=EPA

- HQ

- OPP

- 2014

- 0219 ). During Registration Review, the agency will utilize this analysis to determine if data (i.e., flux studies, route

- specific inhalation tox icological studies) or further analysis is required for NAA.

6.2 Spray Drift

Spray drift is a potential source of exposure to those nearby pesticide applications. This is particularly the case with aerial application, but, to a lesser extent, spray drif t can also be a potential source of exposure from the ground application methods (e.g., groundboom and airblast) employed for NAA. The agency has been working with the Spray Drift Task Force (a task force composed of various registrants which was develope d as a result of a Data Call

- In issued by EPA), EPA Regional Offices and State Lead Agencies for pesticide regulation and other parties to develop the best spray drift management practices (see the agency’s Spray Drift website for more information) 6 . The agency has also developed a policy on how to appropriately consider spray drift as a potential source of exposure in risk assessments for pesticides. The potential for spray drift will be quantitatively evaluated for each pesticide during the Registration Review process which ensures that all uses for that pesticide will be considered concurrently. The approach is outlined in the revised (2012) Standard Operating Procedures For Residential Risk Assessment (SOPs)

- Residential Exposure Assessment Standard Operating Procedures Addenda 1: Consideration of Spray Drift. This document outlines the quantification of indirect

non

- occupational exposure to drift.Page 28 of 79

7 .0 AGGREGATE EXPOSURE AND RISK ASSESSMENT

In accordance with the FQPA, HED mu st consider and agg regate pesticide exposures and risks from three major sources: food, drinking water, and residential exposures (dermal and

inhalation ). In an aggregate assessment, exposures from relevant sources are added together and compared to quantitative estimates o f hazard (e.g., a NOAEL or PAD), or the risks themselves can be aggregated. When aggregating exposures and risks from various sources, HED considers both the route and duration of exposure. The short

- term aggregate assessment includes the combined exposur e from short

- term inhalation and oral exposures. Incidental oral exposure is not anticipated based on registered and proposed use patterns and is not incorporated into the residential handler aggregate assessment. The dermal contribution is likewise omitte d because endpoints were not selected for dermal exposure based on low toxicity in the route specific

studies. Aggregate risk s from chronic exposure to contaminated food and drinking water sources are represented in the chronic dietary assess ment (Section 5.4.2). Acute dietary aggregate risks

were not assessed because points of departure were not established for acute dietary e xposure (Section 5.4.1)

.

7. 1 Shor t

- Term Aggregate Risk
Registrations for residential uses are limited to rooting com pounds and sprout inhibitors. The rooting compounds are applied by holding the plant and dipping the roots into solution. Exposures from these applications are expected to be negligible and, therefore, were not

assessed. Sprout inhibitors are applied by spray or paint brush/roller after pruning trees, or by spraying near the base of the tree after pruning root suckers.

Short

- term aggregate risk was estimated for combined oral and inhalation exposure in adults 20

- 49 applying naphthalene acetate products with a paint

- airless sprayer. Adults 20

- 49 using paint

airless sprayers will experience the highest background dietary (Table 5.4) and inhalation

exposure (Table 6.0) ; therefore, it was considered the worst case sc enario for the aggregate

assessment. E ndpoints selected for the short

- term adult oral exposure and inhalation exposure

were b ased on common effects and could therefore be combined in the aggregate assessment.

Results of the aggregate residential handler assessment are shown below in Table 7. 1

. Aggregated risk indices (ARI) less than 1 are considered risk estimates of concern. Combined
exposure to a dults 20

- 49 using a paint

- airless sprayer resulted in an ARI greater than 1 ; therefore, aggregate exposure to residential handlers is not of concern to HED

.Page 29 of 79 1 HED is concerned if the A ggregated R isk I ndex (ARI) is less than 1

2 Dietary MOE = (short

- term oral NOAEL)/ (chroni c dietary exposure ); Short

- term oral NOAEL = 25 mg/kg/day;

Chronic d ietary exposure for adults 20

- 49 years old = 0.0 13738

3 Dietary ARI = ( Dietary MOE dietary)/ ( Target MOE ) ; Target MOE = 100

4 Residential Inhalation MOE = (short

- term inhalation NOAEL) / ( s hort

- term inhalation exposure); Short

- term inhalation NOAEL = 25 mg/kg/day; Short

- term inhalation exposure = 0.0027 mg/kg/day

5 Inhalation ARI = (Inhalation MOE)/ (Target MOE); Target MOE = 1000

6 Aggregate ARI = 1/ [(1/Dietary ARI) + (1/Inhalation ARI)]

7. 2 Chronic Aggregate Risk

C hronic aggregate exposures include food plus drinking water exposures. As demonstrated

under Section 5. 4 .2 , chronic aggregate risks are not of concern.

8.0 CUMULATIVE RISK

Section 408(b)(2)(D)(v) of FFDCA requires that, when considering whether to establish, modify, or revoke a tolerance, the Agency consider “available information” concerning the cumulative effects of a particular pesticide's residues and “other substances that have a common mechanism of toxicity.”

EPA does not have, at this time, available data to determine whether NAA has a common mechanism of toxicity with other substances. Unlike other pesticides for which EPA has followed a cumulative risk approach based on a common mechanism of toxicity, EPA has not made a common mechanism of toxicity finding as to NAA and any other substances and, NAA does not appear to produce a toxic metabolite produced by other substances which have tolerances in the U. S. For the purpose s of this tolerance reassessment action, therefore, EPA has not assumed that NAA has a common mechanism of toxicity with other substances. For information regarding EPA’s efforts to determine which chemicals have a common mechanism of toxicity and to eval uate the cumulative effects of such chemicals, see the policy statements released by EPA’s OPP concerning common mechanism determinations and procedures for cumulating effects from substances found to have a common mechanism on EPA’s website at http://www. epa.gov/fedrgstr/EPA_PEST/2002/January/Day_16/. Table 7.1. Short

- term Aggregate Risk Calculations Using ARI Approach 1

Population Exposure

Scenario Background Dietary Dermal Residential Exposure Inhalation Residential Exposure Aggregate

ARI (foo d, water, and residential) 6 MOE 2 ARI 3 MOE ARI MOE 4 ARI 5

Adults 20

- 49 years old Paint

airless

sprayer 1810 18. 1 N/A N/A 9200 9.2 6.1Page 30 of 79

9 .0 OCCUPATIONAL EXPOSURE / RISK CHARACTERIZATION

9 .1 Short

- Term Handler Risk

9. 1 .1 Handler Exposure Scenarios

HED uses the term handlers to describe those individuals who are involved in the pesticide application process. HED believes that there are distinct job functions or tasks related to applications and exposures can vary depending on the specifics of each task. Job requirements (amount of chemical used in each application), the kinds of equipmen t used, the target being treated, and the level of protection used by a handler can cause exposure levels to differ in a manner specific to each application event.

Based on the anticipated use patterns and current labeling, types of equipment and techni ques that can potentially be used, short

- term occupational handler exposure is expected from the proposed uses. The quantitative exposure/risk assessment developed for occupational handlers is based on the following scenarios:

 mixing/loading/applying liq uids with a backpack; and

 mixing/loading/applying liquids with a mechanically

- pressurized handgun.

9.1 .2 Handler Exposure Data and Assumptions

A series of assumptions and exposure factors served as the basis for completing the occupational

handler risk assessments. Each assumption and factor is detailed below on an individual basis.

Application Rate : The maximum application rate for sprout inhib itor applications is 0.078 lb

ai /gallon.

Unit Exposures : It is the policy of HED to use the best availabl e data to assess handler exposure. Sources of generic handler data, used as surrogate data in the absence of chemical

- specific data, include PHED 1.1, the AHETF database, the ORETF database, or other registrant

- submitted occupational exposure studies. So me of these data are proprietary (e.g., AHETF data), and subject to the data protection provisions of FIFRA. The standard values recommended for use in predicting handler exposure that are used in this assessment, known as “unit exposures”, are

outlined i n the “Occupational Pesticide Handler Unit Exposure Surrogate Reference Table” 6

, which, along with additional information on HED policy on use of surrogate data, including descriptions of the various sources, can be found at the Agency website 7

.

Area Trea ted or Amount Handled: The area treated or amount handled based on guidance in ExpoSAC Policy 9.1.

6 Available: http://www.epa .gov/opp00001/science/handler

- exposure

- table.pdf

7 Available: http://www.epa.gov/pesticides/science/handler

- exposure

- data.htmlPage 31 of 79

Body Weight: Since the dermal and/or inhalation PO Ds are based on decreased body weight gain, the body weight appropriate for dermal and inhalation asse ssments is the standard body weight for the general population, 80 kg.

Absorption factors: Since the short

- term inhalation POD was based on an oral study, inhalation absorption was assumed to be equivalent.

Exposure Duration: HED classifies exposures fro m 1 to 30 days as short

- term. Exposure duration is determined by many things, including the exposed population, the use site, the pest pressure triggering the use of the pesticide, and the cultural practices surrounding that use site. For most agricultur al uses, it is reasonable to believe that occupational handlers will not apply the same chemical every day for more than a one

- month time frame; however, there may be a large agribusiness and/or commercial applicators who may apply a product over a period of weeks (e.g., completing multiple applications for multiple clients within a region).

For naphthalene acetates, based on the proposed use and registered uses, only short

- term

exposure is expected for the following reasons: (1) naphthalene acetate pro ducts may be used three times per year. (2) NAA is a plant growth regulator which is used for chemical thinning and spout inhibition after pruning in orchard trees. Chemical thinning and pruning are done only at specific times of the year.

Mitigation/Pe rsonal Protective Equipment : Estimates of dermal and inhalation exposure were calculated for various levels of personal protective equipment (PPE). Results are presented for “baseline,” defined as a single layer of clothing consisting of a long sleeved s hirt, long pants, shoes plus socks, no protective gloves , and no respirator, and for the recommended PPE on the naphthalene acetate product labels (baseline attire with chemical

- resistant gloves )

.

Occupational Handler Non

- Cancer Exposure and Risk Estimate Equations The algorithms used to estimate non

- cancer exposure and dose for occupational handlers can be found in Appendix C.

9.1

. 3 Handler Exposure and Risk Estimates

Summaries of the short

- term risks for each exposure scenario are presented in Ta ble 9.1 .3

. The inhalation exposure risks are not of concern to HED (i.e., MOE > 1000 ) for mixers/loaders/applicators wearing basic PPE ( e.g. single layer of clothing, shoes, no gloves, no respirator).Page 32 of 79 1 Based on “Occupational Pesticide Handler Unit Exposure Surrogate Refere nce Table” (Oct 2012); includes data from PHED/ORETF/AHETF

2 Inhalation Dose = Inhalation Unit Exposure ( μg /lb ae) x Conversion Factor (0.001 mg/ug) x Application Rate (lb a i / gal) x Area Treated or Amount Handled Daily ( gal/day) /BW (kg).

3 Inhalation MOE = Inhalation NOAEL (mg/kg/day)/ Inhalati on Dose (mg/kg/day). NOAEL = 25 mg/kg/day. 9.1 .3 Short

- term Occupational Exposure an d Risk Estimates for Naphthalene Acetates.

Exposure Scenario Application

Rate Amount Handled /

Area Treated Inhalation Unit

Exposures (ug/lb ai) 1 Inhalation Dose (mg/kg

- day) 2 Inhalation

MOE 3

No Respirator

Mixing/Loading/Applying a Liquid Formulation to Orchards (Pomegranate Trees)

Backpack

Soil

- /Ground

directed 0.078

lb ai/gallon 40

gallons 2.58 0.000101 250,000

Mechanically

pressurized Handgun 1000 gallons 3.9 0.0038 6,600Page 33 of 79

9. 2 Post Application Exposure

HED uses the term post

- application to describe exposures that occur when individuals are present in an environment that has been previousl y treated with a pesticide (also referred to as re

entry exposure). Such exposures may occur when workers enter previously treated areas to perform job functions, including activities related to crop production, such as scouting for pests or harvesting. Post

- application exposure levels vary over time and depend on such things as the type of activity, the nature of the crop or target that was treated, the type of pesticide application, and the chemical’s degradation properties. In addition, the timing of pesticide applications, relative to harvest activities, can greatly reduce the potential for post

- application exposure.

9. 2

. 1 Occupational P ost

- application Inhalation Expos ure/Risk Estimates

There are multiple potential sources of post

- application inha lation exposure to individuals performing post

- application activities in previously treated fields. These potential sources include volatilization of pesticides and resuspension of dusts and/or particulates that contain pesticides. The agency sought exper t advice and input on issues related to volatilization of pesticides from its Federal Insecticide, Fungicide, and Rodenticide Act Scientific Advisory Panel (SAP) in December 2009, and received the SAP’s final report on March 2, 2010 ( http://www.epa.gov/sci poly/SAP/meetings/2009/120109meeting.html ). The agency has evaluated the SAP report and has developed a Volatilization Screening Tool and a subsequent Volatilization Screening Analysis ( http://www.regulations.gov/#!docketDetail;D=EPA

- HQ

OPP

- 2014

- 0219 ). During Registration Review, the agency will utilize this analysis to determine if data (i.e., flux studies, route

- specific inhalation toxicological studies) or further ana lysis is required for naphthalene acetates.

In addition, the Agency is continuing to evaluate the available post

- application inhalation exposure data generated by the Agricultural Reentry Task Force. Given these two efforts, the Agency will continue to i dentify the need for and, subsequently, the way to incorporate occupational post

- application inhalation exposure into the agency's risk assessments.

Although a quantitative occupational post

- application inhalation exposure assessment was not performed, an inhalation exposure assessment was performed for occupational/commercial handlers. Handler exposure resulting from application of pesticides outdoors is likely to result in higher exposure than post

- application exposure. Therefore, it is expected that t hese handler inhalation exposure estimates would be protective of most occupational post

- application inhalation exposure scenarios.

9. 2

. 2 Occupational Post

- application Dermal Exposure/Risk Estimates

Dermal exposure up to 1 000 m g/kg/day did not result in systemic toxicity for any of the naphthalene acetates tested (NAA sodium salt, NAA, and NAA acetamide); therefore, a dermal
post

- application assessment and DFR study are not required at this time.Page 34 of 79

9. 2

. 3 Restricted Entry Interval

The Restricted Entr y Interval (REI) specified on the proposed label for T re

- Hold Sprout Inhibitor

A

- 112 is based on the acute toxicity of NAA ethyl ester. NAA ethyl ester is classified as Toxicity Category III via the dermal route and Toxicity Category IV for skin irritatio n potential.

It is not a skin sensitizer. Short

- term post

- application risk estimates were not a concern on day 0 (12 hours following application) for all post

- application activities. Under 40 CFR 156.208 (c) (2) (iii), ai’s classified as Acute III or IV for acute dermal, eye irritation and primary skin irrigation are assigned a 12

- hour REI. Therefore, the [156 subpart K] Worker Protection Statement interim REI of 12 hours is adequate to protect agricultural workers from post

application exposures to NAA ethyl ester and NAA sodium salt.

10. 0 REFERENCES

1

- Naphthaleneacetic acid (NAA), its salts, ester, and acetamide

. New Use in/on Pomegranate. Summary of Analytical Chemistry and Residue Data. D423409. T. Morton. November 18, 2015.

Naphthalene Aceta tes

- Chronic Dietary and Drinking Water Exposure and Risk Assessment for Section 3 New Use of Naphthalene Acetic Acid

- ester on Pomegranate. D426996

, T. Morton

, November 18, 2015

.

1

- Naphthaleneacetic acid: Summary of Hazard and Science Policy Council (HASP OC) Meeting of May 8, 2014: Recommendations on the requirement of immunotoxicity. TXR 0056968

, J. Leshin, May 21, 2014

.

Tier 1 Drinking Water Analysis for the IR

- 4 Petition to Register the Use of 1

- Naphthaleneacetic Acid, Ethyl Ester for the Use on Pomeg ranate

. D423410, J.L. Melendez, May 14, 2015

.

Naphthalene Acetates Human Health Risk Assessment for a Proposed Use on Avocado, Mango, Mamey Sapote, Rambutan, and updating crop gr oup Fruit, Pome, Group 11

- 10. D 404398, T. Morton, January 16, 2013.

Naphtha lene Acetic Acid and Salts, Ethyl Ester, and Acetamide (Naphthalene Acetates). Occupational and Residential Exposure Assessment for a Proposed Use on Avocado, Mango, Mamey Sapote, Rambutan, and updating crop group Fruit, Pome, Group 11

- 10. D406255

, S

Humm el, January 16, 2013

.

Naphthalene Acetates: Summary of Hazard and Science Policy Council (HASPOC) Meeting of September 13, 2012: Recommendations on data requirements for inhalation, acute and subchronic neurotoxicity, and immunotoxicity studies. TXR 00 56465

, K

. Rury, October 16,

2012

.

1

- Naphthaleneacetic acid (NAA), its salts, ester, a nd acetamide. Expansions of Existing Crop Group/Representative Commodity Uses to Fruit, Pome, Group 11

- 10 and New Uses in/onPage 35 of 7 9

Avocado, Mango, Mamey Sapote, and Rambuttan. Summary of Analytical Chemistry and

Residue Data. D399621

, G. Otakie, October 3, 2012

.

Branagan MF, Audia W, Ballard G, Boyd H, Dickson D, Dodd N, Garczynski L, Holst R, Johnston T, and Sullivan E. Naphthaleneacetic acid its salts, ester, and acetamide . Pesticide registration standard. USEPA. July 31, 1981.Page 36 of 79

APPENDICIES

Appendix A. Toxicology Profile and Executive Summaries

A.1 Toxicology Data Requirements
The requirements (40 CFR 158.500) for naphthalene acetate food use are in Table 1. Use of the new guideline numbers does not imply that the new (1998) guideline protocols were used.

Study Technical

Required Satisfied

870.1100 Acute Oral Toxicity

................................ ....................... 870.1200 Acute Dermal Toxicity

................................ .................. 870.1300 Acute Inhalation Toxicity

................................ .............. 870.2400 Primary Ey e Irritation

................................ .................... 870.2500 Primary Dermal Irritation

................................ .............. 870.2600 Dermal Sensitization

................................ ...................... yes

yes

yes

yes

yes

yes yes

yes

yes

yes

yes

yes

870.3100 Oral Subchronic (rodent)

................................ ............... 870.3150 Oral Subchronic (nonrodent)

................................ ......... 870.3200 21

- Day Dermal

................................ .............................. 870.3250 90

- Day Dermal

................................ .............................. 870.3465 90

- Day Inhalation

................................ .......................... yes

yes

yes

no

yes 1 yes

yes

yes

-

no

870.3700a Developmental Toxicity (rodent)

................................ ... 870.3700b Developmental Toxicity (nonrodent)

............................. 870.3800 Reproduction

................................ ................................ . yes

yes

yes yes

yes

yes

870.4100a Chronic Toxicity (rod ent)

................................ .............. 870.4100b Chronic Toxicity (nonrodent)

................................ ........ 870.4200a Oncogenicity (rat)

................................ .......................... 870.4200b Oncogenicity (mouse)

................................ .................... 870.4300 Chronic/Oncogenicity

................................ .................... yes

yes

yes

yes

yes yes

yes

yes

yes

yes

870.5100 Mutagenicity

— Gene Mutation

- bacterial

..................... 870.5300 Mutage nicity

— Gene Mutation

- mammalian

................ 870.5xxx Mutagenicity

— Structural Chromosomal Aberrations

... 870.5xxx Mutagenicity

— Other Genotoxic Effects

....................... yes

yes

yes

yes yes

yes

yes

yes

870.6100a Acute Delayed Neurotoxicity (hen)

............................... 870.6100b 90

- Day Neurotoxicity (hen)

................................ ........... 870.6200a Acute Neurotoxicity Screening Battery (rat)

................. 870.6200b 90

- Day Neurotoxicity Screening Battery (rat)

............... 870.6300 Develop. Neurotoxicity

................................ ................. no

no waived 2

waived 2

no -

-

-

-

-

870.7485 General Metabolism

................................ ...................... 870.7600 Dermal Penetration

................................ ........................ 870.7800 Immunotoxicity

................................ ............................. yes

no wavied 3 yes

-

-

1 Required per HED HASPOC (TXR 0056465)

2 Waived per HED HASPOC (TXR 0056465)

3 Waived per HED HASPOC (TXR 0056968)Page 37 of 79

A.2 Toxicity Profiles
Note: Only guideline studies for NAA acetamide, NAA, NAA so dium s alt

, and NAA ethyl ester are included in the toxicity profile table. End use product specific acute studies are available for ammonium NAA and NAA potassium salt but were not considered in the assessment for the new use on
pomegranate.

Table A.2 Acute, S ubchronic and Chro nic Toxic Profile

– Naphthalene A cetates

Study PC 056001: Acetamide PC 056002: NAA PC 056007: Na salt PC 056008: Ethyl ester

Acute

- Oral MRID 43495901 (1994)

LD 50 > 5050 mg/kg Category IV MRID 00103128 (1982)

LD 50 (95% C.I.) =

252 0 mg/kg (2100

- 3021) Category III MRID 00108829 (1982)

LD 50 (95% C.I.) = (M) 1.35 g/kg (1.12

– 1.64) (F) 0.933 g/kg (0.631

- 1.38) Category III MRID 43494101 (1994)

LD 50 (95% C.I.) = 2186 (1907

- 2506) mg/kg Category III

Acute

- Dermal MRID 43495902 (199 4)

LD 50 > 2020 mg/kg Category III MRID 00103129 (1982)

LD 50 > 2 g/kg Category III MRID 00108829 (1982)

dermal LD 50 > 2 g/kg Category III MRID 43494102 (1994)

LD 50 > 2020 mg/kg Category III

Acute

- Inhalation MRID 43495903 (1994)

LC 50 > 2.17 mg/L Category IV MRID 00128256 (1983)

LC 50 > 0.45 mg/L Category III MRID 43494103 (1994)

LC 50 > 2.13 mg/L Category IV

Eye Irritation MRID 00103051 (1982)

corrosive Category I

MRID 43495904 (1994) minimally irritating Category IV MRID 00103127 (1982)

corrosive Category I MRID 00108829 (1982)

corrosive Category I MRID 43494104 (1994) minimally irritating Category IVPage 38 of 79 Table A.2 Acute, S ubchronic and Chro nic Toxic Profile

– Naphthalene A cetates

Study PC 056001: Acetamide PC 056002: NAA PC 056007: Na salt PC 056008: Ethyl ester

Dermal Irritation MRID 00103220 (1982)

Non

- irritating Category IV MRID 00103127 (1982)

Non

- irritating Category IV MRID 00108829 (1982)

Non

- irritating Category IV MRID 00103053/

00103218 (1982)

Non

- irritating Category IV

Sensitization MRID 43495905 (1994)

Not a skin sensitizer. No positive control. Unacceptable MRID 00153217 (1984)

Not a skin sensitizer MRID 43494105 (1994)

Not a skin sensitizer. No positive control. UnacceptablePage 39 of 79 Table A.2 Acute, S ubchronic and Chro nic Toxic Profile

– Naphthalene A cetates

Study PC 056001: Acetamide PC 056002: NAA PC 056007: Na salt PC 056008: Ethyl ester

Sub chronic

- Rat MRID 43896001 (1995) Acceptable/Guideline 0, 250, 1,000, or 4,000 ppm (0, 19.1, 73.8, or 292.1 mg/kg/day for males and 0, 20.4, 81.5, or 313.5 mg/kg/day for females) in

t he diet for 90 days

LOAEL = 292.1 mg/kg/day based on decreased bw, bw gain & food consumption, and

increased relative liver weights with adaptive histopathological changes in

both sexes.

NOAEL = 73.8 mg/kg/day MRID 00043624 (1979) Acceptable/Guideline 0, 50, 150, or 300 mg/kg/day to SD rats (20/sex/dose) in diet for 13

weeks

LOAEL = 300 mg/kg/day based on decreased body weight in both sexes and enlarged liver weights in

females.

NOAEL = 150 mg/kg/day MRID 42932601 (1993) Acceptable/Guideline 0, 20 0, 2000, or 8000 ppm (13.9, 136.6, and

564.9 for males and 15.2, 149.3, and 583.4 mg/kg/day for females)

in the diet for 13 weeks

LOAEL = 136.6 mg/kg/day for males

an d 149.3 mg/kg/day

for females based on

decreased hematocrit and hemoglobin,

increased l iver weights

and vacuolation of the periportal hepatocytes along with hypertrophy

of the cells of the

adrenal cortex zona glomerulosa.

NOAEL = 13.9 mg/kg/day for males and 15.2 mg/kg/day

for females MRID 43896002 (1995) Acceptable/Guideline 0, 400, 2000 or 8000 ppm (Average doses at study end were 19

- 25;

92

- 123; and 388

- 519 mg/kg/day for males

females) in the diet for

13 weeks

LOAEL = 594 mg/kg/day based on lower bw, bw gain, and food consumption.

Males and females at

this dose also exhibited

increas ed total bilirubin (19

- 21% higher) in conjunction with reduced RBC counts, hemoglobin, and

hematocrits.

NOAEL = 144 mg/kg/day

10

- day range finding

- rat MRID 00043623 (1976) Acceptable/Non

-Page 40 of 79 Table A.2 Acute, S ubchronic and Chro nic Toxic Profile

– Naphthalene A cetates

Study PC 056001: Acetamide PC 056002: NAA PC 056007: Na salt PC 056008: Ethyl ester

Guideline 0, 250, 1000 or 4000 mg/kg bw/day by gavage

for 10 days (3 rats/sex/dose).

Death of all high dose rats,

one female in the mid dose

and none in the low dose. Dose related depression in body weight gain and food consumption. Discoloration of lungs, liver and kidneys, distended bladder (high dose), bloo d and gas in the

GI tract.

MTD = 250 mg/kg/day

Sub chronic

- Dog MRID 43895901 (1995) Acceptable/Guideline 0, 30, 100, or 300 mg/kg/day via capsule for

13 weeks.

LOAEL = 300 mg/kg/day based on increased platelet count, decreased red cell

parame ters, and increased mean corpuscular volume

which correlate with MRID 00136446 (1979) Acceptable/Guideline 0, 50, 150, or 300 mg/kg/day via gel atin capsule for 6 months

LOAEL = 50 mg/kg/day

, the lowest dose tested, based on hepatic liver changes (pericholangistis)

NOAEL = not derived in MRID 42983801 (1993) Acceptable/Guideline 0, 25, 150, or 450 mg/kg/day via capsule

for 13 weeks

LOAEL =150 mg/kg/day based on

lesions of the GI tract and hypocellularity of

the bone marrow MRID 43914901 (1995) Acceptable/Guideline 0, 40, 125, or 400 mg/kg/day via gelatin capsules for 13 weeks.

LOAEL = 400 mg/kg/day ba sed on soft/liquid feces and depressed body weight gains of male andPage 41 of 79 Table A.2 Acute, S ubchronic and Chro nic Toxic Profile

– Naphthalene A cetates

Study PC 056001: Acetamide PC 056002: NAA PC 056007: Na salt PC 056008: Ethyl ester

histopathological changes observed in the liver, spleen, and bone marrow in

both sexes.

NOAEL = 100 mg/kg/day this study.

NOAEL = 25 mg/kg/day female dogs. Blood parameters (RBC, hemoglobin, hematocrit and mean platelet volume) were all depressed in the male dogs at this level.

NOAEL = 125 mg/kg/day

21

- day

- Dermal MRID 43581001 (1995) Acceptable/Guideline 0, 100, 300, or 1000 mg/kg

for 6

- 6.5 hours/day, 5 days/week, for 3 weeks.

LOAEL = was not

established

NOAEL = 1000 mg/kg bw/day (the highest dose tested) MRID 43134701 (1994) Acceptable/Guideline 0, 100, 300, o r 1000 mg/kg for 6

- 6.5 hours/day, 5 days/week,

for 3 weeks.

Systemic LOAEL was not established

Systemic NOAEL =

10 00 mg/kg/day

Dermal LOAEL = 1000 mg/kg/day based on microscopic changes

in the skin

Dermal NOAEL = 300 mg/kg/day MRID 43581002 (1995) Acceptable/Guideline 0, 100, 300, or 1000 mg/kg for 6

- 6.5 hours/day, 5 days/week,

for 3 weeks.

Systemic LOAEL was not established

Systemic NOAEL =1000 mg/kg/day

Dermal LOAEL = 100 mg/kg/day based on the epidermal hyperplasia and hyperkeratosis,

seba ceous gland hyperplasia, and dermal

inflammation in thePage 42 of 79 Table A.2 Acute, S ubchronic and Chro nic Toxic Profile

– Naphthalene A cetates

Study PC 056001: Acetamide PC 056002: NAA PC 056007: Na salt PC 056008: Ethyl ester

treated skin.

Dermal NOAEL < 100 mg/kg/day

28

- day inhalation Not available

Developmental Rat MRID 00042765 (1977) Acceptable/Guideline 0, 10, 50 or 250 mg/kg/day via gastric intubation to

pre gnant rats (24/group) from days 6 through 15 of gestation

Maternal LOAEL = 250 MRID 46685803 (2004) Acceptable/Guideline 0, 15, 50 or 150 mg/kg bw/day via gavage to

24 female SD rats/dose from days 5 through 21 (inclusive) of gestation.Page 43 of 79 Table A.2 Acute, S ubchronic and Chro nic Toxic Profile

– Naphthalene A cetates

Study PC 056001: Acetamide PC 056002: NAA PC 056007: Na salt PC 056008: Ethyl ester

mg/kg/day based on decreased body weight gain during the compound

administration

Maternal NOAEL = 50 mg/kg/day

Developmental LOAEL >250 mg/k/day

Developmental NOAEL =

250 m g/kg/day Maternal LOAEL >150 mg/kg bw/day

Maternal NOAEL = 150 mg/kg bw/day (HDT)

Developm ental

LOAEL = 150 mg/kg/day based on decreased fetal weight

and minor skeletal changes (centrum 5 not ossified, cervical arch 7 cartilage fused to arch 6 cartilage, shortened 7 th
cervical rib)

Developmental

NOAEL = 50 mg/kg/day

Developmental

- Rabbit MRID 00137821,

00137822 (1983) Acceptable/Guideline 0, 37.5, 75 or 150 mg/kg/day via oral gavage from days 6 through 27 of gestation

Maternal LOAEL = 150 mg/kg/day based on day MRID 46685801 (2003) Acceptable/Guideline 0, 30, 100 or 300 mg/kg bw/day in water via gavage from days 5 through 29 (inclusive) of gestation

maternalPage 44 of 79 Table A.2 Acute, S ubchronic and Chro nic Toxic Profile

– Naphthalene A cetates

Study PC 056001: Acetamide PC 056002: NAA PC 056007: Na salt PC 056008: Ethyl ester

based on lethality

Maternal NOAEL = 75 mg/kg/day

Developmental LOAEL =

> 150 mg/kg/day

Developmental NOAEL = 150 mg/kg/day (HDT) Maternal LOAEL = 300 mg/kg/day based

on reduce d body weight, body weight gain and reduced food consumption, clinical signs (few/no feces)

and stomach irritation (red/black spots/areas in the glandular mucosa of the stomach) and

Maternal NOAEL = 100 mg/kg/day

Developmental

LOAEL = 300 mg/kg/day bas ed on an

increase in the overall

incidences of fetuses

with minor skeletal

defects and variants (dumbell ossification of

the 7 th thoracic

centrum, extra
thoracolumbar ribs and 27 pre

- pelvic vertebrae)

and a decrease in

ossification of the

manus

Developme ntalPage 45 of 79 Table A.2 Acute, S ubchronic and Chro nic Toxic Profile

– Naphthalene A cetates

Study PC 056001: Acetamide PC 056002: NAA PC 056007: Na salt PC 056008: Ethyl ester

NOAEL = 100 mg/kg/day

Reproduction MRID 43796301 (1995) Acceptable/Guideline 0, 100, 1000 or 3000 ppm (0, 7, 69, and 210 mg/kg/day for males and 0, 8, 81, and 239 mg/kg/day for females)

via diet

Systemic and repro./develop

LOAEL = 210 mg/kg /day for males

and 23 9 mg/kg/day for

females based upon reduced bw gain and food consumption in parental animals and reduced litter survival, and pup weight throughout lactation in both generations of offspring.

Systemic and repro./develop

NOAEL = 69

mg /kg/day for malesPage 46 of 79 Table A.2 Acute, S ubchronic and Chro nic Toxic Profile

– Naphthalene A cetates

Study PC 056001: Acetamide PC 056002: NAA PC 056007: Na salt PC 056008: Ethyl ester

and 8 1 mg/kg/day for

females

Chronic/Oncogenicity

- Rat MRID 44157501 (1996) Acceptable/Guideline 0, 100, 1000, or 5000 ppm (0, 4.4, 43.8, and 224.5 mg/kg/day for males and 0, 5.6, 55.8, and 303.6 mg/kg/day for females) via diet to
Crl:CD® BR rats

LOAEL = 224.5 mg/kg/day for males and 303.6 mg/kg/day

for fem ales based on an

increased incidence of stomach (mucosal gland dilation) and lung lesions (focal alveolar macrophages) in both sexes, and on lowered bw gain and food

efficien cy in females

NOAEL = 43.8 mg/kg/day for males and 55.8 mg/kg/day

for femalesPage 47 of 79 Table A.2 Acute, S ubchronic and Chro nic Toxic Profile

– Naphthalene A cetates

Study PC 056001: Acetamide PC 056002: NAA PC 056007: Na salt PC 056008: Ethyl ester

*Increased incidence (p

 0.01) of uterine

endometrial stromal polyps in high

- dose females (2/60, 1/60, 3/60, 13/60 at 0, 100, 1000, 5000 ppm, respectively).

Chronic

- Mou se NCI study (Innes et al 1969) Acceptable/Non

- Guideline

NAA acetamide was tested at one dose (MTD according to the published article) as part of a testing program of 120 chemicals. Only the preliminary results were published. The test

materials were ad ministered to two hybrid strains of

mice : C57BL/6 x C3H/Anf

and C57BL/6 x AKR (18/sex/hybrid strain). The

mice were administered

NAA acetamide at one week of age by stomach intubation at 464 mg/kg/day until weaning at 4 weeks of age and administered the

NAA acetamide in the diet at 1298 ppm for approx. 18 MRID 46685802 (2004) Acceptable/Guideline 0, 100, 500, or 2500 ppm [0, 10.8, 53.3, 276.0 / 0, 14.3, 70.9, 348.7 mg/kg bw/day M/F, respectively] via

diet to CD

- 1 Alpk mice

for at least 80 weeks

LOAEL = 276 mg/kg/day for males

and 348.7 mg/kg/day

for females based on ↓body weight, food consumption, ↑ liver and kidney weights in both sexes and epididymis in males, ↓brain weights in males, hepato

cellular vacuolation in males, adenomas of thePage 48 of 79 Table A.2 Acute, S ubchronic and Chro nic Toxic Profile

– Naphthalene A cetates

Study PC 056001: Acetamide PC 056002: NAA PC 056007: Na salt PC 056008: Ethyl ester

months.

*Gross and histopath

examination of the mice at the end of the feeding period did not reveal a significant increase in

tumors over the controls. liver and lung in males, ↑in the incidence of multiple tumors in

females

NOAEL = 53.3 mg/kg/day for males

and 70 .9 mg/kg/day

for females

*There was no

treatment related

increase in tumor

incidence when compared to controls. Dosing was considered adequate based on the

effects observed on the top dose (2500 ppm/kg/day).

Chronic

- Dog MRID 43744201 (1995)

Ac ceptable/Guideline 0, 15, 75, or 225 mg/kg/day via gelatin capsule for 52 weeks

LOAEL= 75 mg/kg/day in mal es and 225 mg/kg/day in

females based onPage 49 of 79 Table A.2 Acute, S ubchronic and Chro nic Toxic Profile

– Naphthalene A cetates

Study PC 056001: Acetamide PC 056002: NAA PC 056007: Na salt PC 056008: Ethyl ester

emesis, capsular regurgitation incidences, gross and histopathologic changes in stomachs, and

sinusoidal h istiocytosis

in livers.

NOAEL= 15 mg/kg/day in males and 75 mg/kg/day in

females.

Gene mutation

- bacterial MRID 43581006 (1996) Acceptable/Guideline

Salmonella

Five doses 100

- 5000 ug/plate. No mutagenic

effect with or without S9

activation MRID 00042761 (1978) Acceptable/Guideline Escherichia coli polA

. Strains W3110 and p3478 at 1, 2 or mg/ml. Not mutagenic.

MRID 00042762 (1978) Acceptable/Guideline

Salmonella.

At 0.5

- 5000 ug/plate. Not mutagenic MRID 43581004 Acceptable/Guideline

Salmo nella

Five doses 33

- 5000 ug/plate. No mutagenic

effect with or without

S9 activation

Gene mutation

- mammalian: mouse lymphoma cells MRID 43580202 (1995) Acceptable/Guideline

- S9: not mutagenic +S9 mutagenic at 100 ug/mL and above MRID 43580201 (1994) Acceptable/Guideline

- S9: not mutagenic +S9 mutagenic at 300 ug/mL and abovePage 50 of 79 Table A.2 Acute, S ubchronic and Chro nic Toxic Profile

– Naphthalene A cetates

Study PC 056001: Acetamide PC 056002: NAA PC 056007: Na salt PC 056008: Ethyl ester

Erythrocyte micronuleus

mice MRID 43581005 (1994)

Acceptable/Guideline IP injections 250, 500 or 1000 mg/kg to 5 mice/sex. Lethargy and death at high

dose. Did not in duce a clastogenic or aneurogenic

effect. MRID 00042763 (1979) Acceptable/Guideline IP injections 60 or 125 mg/kg to 4 mice/sex. No overt symptoms at high dose. Negative. MRID 43581003 (1994) Acceptable/Guideline IP injections 305, 610, or 1220 mg/kg to 5 mice/sex. Lethargy and death (48%) at high

dose. Did not induce a clastogenic or aneurogenic effect

Mitotic gene conversion: Saccharomyces cervisiae MRID 00042758, 00042759, 00042760 (1978)

NAA was tested at 10

- 2

, 10

- 3 , 10

- 4 , 10

- 5 , 10

- 6 M..

NA A was not mutagenic in this test system. Unacceptable . No purity, not run at toxic dose, no S9

activation

Rodent dominant lethal assay MRID 00042764 (1979) Acceptable/Guideline Oral doses of 125, 250, or 500 mg/kg/day to 10 male

rats/dose for 5 days. NAA did not produce dominant

lethal effects as measured by pre implantation and post implantation lossesPage 51 of 79 Table A.2 Acute, S ubchronic and Chro nic Toxic Profile

– Naphthalene A cetates

Study PC 056001: Acetamide PC 056002: NAA PC 056007: Na salt PC 056008: Ethyl ester

Metabolism Dixon et al. 1977. NAA 14 C as Na salt . 60

- 100% of the AD was excreted in the urine by the end of 48 hours.

The glucuronic aci d conjugate (GAC) : major urinary metabolite in man, rhesus monkey, marmoset, rabbit, rat, and fruit bat. In the cat, no GAC was detected; but taurine and glycine conjugates. The glycine conjugate was a major urinary metabolite (>20%) in the cat, squirrel and bushbaby monkey and a minor metabolite in rabbit, rat, capuchia and marmoset monkey. 1

- NAA glutamine conjugate was formed only in the cynomolgus, squirrel and capuchin monkeys and marmoset in amounts not exceeding 3% of the AD. 1

- NAA taurine was excr eted by all species except the rabbit, rat and the fruit bat. It was a major excretion product (>6%) in the squirrel and capuchin monkeys, the marmoset and the cat. When female rats were given ip doses of 5

- 500 mg/kg, bile duct

cannulation showed that 10

- 44% of the radioactivity was present in the bile 3 hours after injection. While 0.6

- 32% was present in the urine. At the higher doses urinary GAC predominated whereas at the lower doses the glycine conjugates predominated. In the bile the GAC was the ma jor metabolite (>80% of the bile radioactivity) and the glycine conjugate was a minor metabolite (<4% of the bile radioactivity). There was no analysis of the fecal radioactivity.

Lethco and Brouwer, 1966. Carboxy

- 14 C

- 1

- NAA as NA salt in male rats. W ithin 3 days, 71

- 90% of the AD was excreted in the urine. At the lower doses (0.1

- 100 mg/kg) most of the radioactivity was excreted during the first 24 hours, while at the higher dose (250 mg/kg), excretion was highest on the second day. Fecal excretion

was 3

- 10% at the 0.1

- 1.0 mg/kg doses and 14

- 21% of the AD at the 100 and 250 mg/kg doses. After the third day, no radioactivity was detected in the feces or urine at any dose. 70

- 93% of the urinary radioactivity was NAA glycine conjugate and NAA GAC . T he GAC predominated at the two high doses and the glycine conjugate predominated at the lower dose. Minor amounts of NAA and two other minor unidentified metabolites were detected in the urine. Bile cannulation experiments demonstrated biliary metabolis m and excretion of the test material. At the high dose a maximum of 29% of the AD was recovered at 6 hours, while a maximum of 54% was recovered at the low dose at 2 hours. At the low dose, the NAA glycine conjugate was the major urinary metabolite and t he NAA GAC was a minor metabolite, while in the bile the preponderance of these two metabolites was reversed. Unchanged NAA was detected in the bile but not in the urine at both doses. At the high dose the NAA GAC was the major metabolite in both urine a nd bile while the glycine conjugate was a

minor metabolite.

MRID 43961701 (1996), Acceptable/Guideline . Rats (5/sex) were given a single 1 or 100 mg/kg bw oral dose of [ 14 C] ring labeled

- 1

- naphthaleneacetic acid, ethyl ester, or a 14

- day repeated dose ( 1 mg/kg/day) of unlabeled material followed by a single dose of the labeled material. Overall recovery of AD was 98.6

- 101.8%. NAAPage 52 of 79 Table A.2 Acute, S ubchronic and Chro nic Toxic Profile

– Naphthalene A cetates

Study PC 056001: Acetamide PC 056002: NAA PC 056007: Na salt PC 056008: Ethyl ester

ethyl ester was readily absorbed and excreted within 36

- 48 hours following all exposure regimens (urinary

excretion: 67.6

- 85.3% of the AD at the low dose and 61.8

- 78% of the AD at the high dose). Fecal excretion was

12.3

- 35.2% of the AD. Tissue radioactivity was very low. The major pathway of metabolism involved ester cleavage followed by glycine and glucuronide conjugatio n at the low and low repeat doses. At the high dose, glucuronide conjugation appeared to play a more important role following ester cleavage. Parent compound was detected at low concentrations (0.5

- 4.7% of administered) only in feces.

MRID 43963301 (19 96), Acceptable/Guideline . Rats (5/sex) were given either a single 1 or 100 mg/kg bw oral dose, or a 14

- day repeated dose (1 mg/kg/day) using [ 14 C] ring labeled

- 1

- naphthaleneacetamide (NAAD). Overall recovery of the AD was 97.2

- 101%. NAAD was readily a bsorbed and excreted within 36 hours (urinary

excretion: 70.8

- 74.1% of the AD at the low dose, single or multiple, 66.2

- 69.5% of the AD excreted in urine at the high dose). Fecal excretion was 21.6

- 26.2% of the AD. Tissue radioactivity was very low (<0.5 % of the AD). Metabolism involved amide cleavage followed by glycine conjugation (13.7

- 47.3% of the AD) glucuronide conjugation (4.5

- 7.0% of the AD at the low dose and 12.8

- 18.1% of the AD at the high dose in the urine). For feces, the major metabolite detected was the dihydrodiol of naphthaleneacetamide (3.6

- 11.3% of the AD). Parent compound was detected at low concentrations (0.7

- 1.9% of administered) only in feces.Page 53 of 79

A.3 Hazard Identification and Endpoint Selection

A.3.1 Acute Population Adjusted D oses (aPAD)

– All Populations

An acute RfD for the general population or any population subgroups was not selected because no effect attributable to a single (or few) day(s) oral exposure was observed in animal studies

A.3.2 Chronic Population Adjusted D ose (cPAD)

– All Populations

Selected Study: Subchronic and Chronic Study in Dogs

MRID No.: 42983801 ( Subchronic)

, 43744201 ( Chronic)

Executive Summary : See Appendix A.4, Guideline [§ 870. 3150, 870. 4100b]

Dose and Endpoint for Risk Assessment : The N OAEL (25 mg/kg/day) from two co

- critical dog studies was based on stomach lesions (slight to moderate necrosis of fundus and pyloric epithelium), and slight sinusoidal histiocytosis in the liver of males observed at 75 mg/kg/day in the chronic dog study

.

Uncertainty Factors (UF ): 100 ( 10X for interspecies extrapolation, 10x for intraspecies

variation , and 1x FQPA SF)

Comments about Study/Endpoint: The POD for the chronic dietary assessment was based on lesions of the GI tract (ulcerative duodenitis and a cute or erosive gastritis) and hypocellularity of the bone marrow at 150 mg/kg/day in the subchronic dog study. This endpoint was protective of the stomach lesions (slight to moderate necrosis of fundus and pyloric epithelium), and slight

sinusoidal histio cytosis in the liver of males observed at 75 mg/kg/day in the chronic dog study and the developmental a n d offspring effects observed at > 150 mg/kg/day. The higher NOAEL from the subchronic study was an acceptable chronic endpoint without additional uncert ainty factors because the two studies based endpoints around similar adverse effects and there was no evidence of progression with increased exposure duration. The sodium salt is the most toxic in

the subchronic studies thus the endpoints selected from thi s study are protective of NAA and NAA ethyl ester subchronic and chronic exposures.

A.3.3 Dermal Absorption General Population cPAD = (NOAEL ) 25 mg/kg/day = 0.25 mg/kg/day (UF) 100Page 54 of 79

A dermal penetration study was not submitted for the naphthalene acetates.

A.3.4 Adult Oral Exposure (Short

- Term)

Selected Study: Subch ronic and Chronic Study in Dogs

MRID No.: 42983801 ( Subchronic)

, 43744201 ( Chronic)

Executive Summary : See Appendix A.4, Guideline [§ 870. 3150, 870. 4100b]

Dose and Endpoint for Risk Assessment : The NOAEL (25 mg/kg/day) from two co

- critical dog studie s was based on stomach lesions (slight to moderate necrosis of fundus and pyloric epithelium), and slight sinusoidal histiocytosis in the liver of males observed at 75 mg/kg/day in the chronic dog study

.

Uncertainty Factors (UF ): 100 ( 10X for interspecies extrapolation and 10x for intraspecies

variation )

Comments about Study/Endpoint: The short

- term oral endpoint was selected exclusively for the aggregate assessment. The POD for the short

- term adult oral assessment was based on lesions of the GI tract (u lcerative duodenitis and acute or erosive gastritis) and hypocellularity of the bone marrow at 150 mg/kg/day in the subchronic dog study. This endpoint was protective of the stomach lesions (slight to moderate necrosis of fundus and pyloric epithelium), an d slight sinusoidal histiocytosis in the liver of males observed at 75 mg/kg/day in the chronic dog study and the developmental a n d offspring effects observed at > 150 mg/kg/day. The higher NOAEL from the subchronic study was an acceptable chronic endpoint without additional uncertainty factors because the two studies based endpoints around similar adverse effects and there was no evidence of progression with increased exposure duration. The sodium salt is the most toxic in

the subchronic studies thus the e ndpoints selected from this study are protective of NAA and NAA ethyl ester short

- term exposures.

A.3.5 Dermal Exposure (Short

- Term)

Dermal exposure up to 1000 mg/kg/day did not result in systemic toxicity for any of the naphthalene acetates tested (NAA sodium salt, NAA, and NAA acetamide); therefore a dermal assessment was not conducted. A dermal absorption study was not submitted; however, the absence of systemic toxicity at high dose dermal exposure suggests absorption is limited. Furthermore, in sever al naphthalene acetates (including NAA ethyl ester) irritation effects precede systemic effects precluding dermal exposures of > 1000 mg/kg/day (or 100 mg/kg/day in the case of the ethyl ester ) . The in utero susceptibility in the rat developmental study wa s not used to set endpoints for a dermal assessment because dermal exposure is unlikely to provide the internal dose required to elicit these effects based on the low absorption potential and irritant properties of the naphthalene acetates

.

A.3. 6 Inhalati on Exposure (Short

- Term)Page 55 of 79

Selected Study: Subchronic and Chronic Study in Dogs

MRID No.: 42983801 ( Subchronic)

, 43744201 ( Chronic)

Executive Summary : See Appendix A.4, Guideline [§ 870. 3150, 870. 4100b]

Dose and Endpoint for Risk Assessment : The NOAE L (25 mg/kg/day) from two co

- critical dog studies was based on stomach lesions (slight to moderate necrosis of fundus and pyloric epithelium), and slight sinusoidal histiocytosis in the liver of males observed at 75 mg/kg/day in the chronic dog study

.

Unc ertainty Factor (UF) : 1000 ( 10x for interspecies extrapolation, 10x for intraspecies

variation and 10x for the lack of subchronic inhalation study )

.

Comments about Study/Endpoint: A subchronic inhalation study was not submitted by the registrant. In lieu of a route specific study the NOAEL from the co

- critical dog study was used to set inhalation endpoints

. The POD for the inhalation assessment was based on lesions of the GI tract (ulcerative duodenitis and acute or erosive gastritis) and hypocellularity of the bone marrow at 150 mg/kg/day in the subchronic dog study. This endpoint was protective of the stomach lesions (slight to moderate necrosis of fundus and pyloric epithelium), and slight sinusoidal histiocytosis in the liver of males observed at 75 mg /kg/day in the chronic dog study and the developmental a n d offspring effects observed at > 150 mg/kg/day. The higher NOAEL from the subchronic study was an acceptable chronic endpoint without additional uncertainty factors

because the two studies based end points around similar adverse effects and there was no evidence of progression with increased exposure duration. The sodium salt is the most toxic in the subchronic studies thus the endpoints selected from this study are protective of NAA and NAA ethyl est er short

- term exposures

.

A.4 Executive Summaries f or Supporting Toxicity Studies

A.4.1 Subchronic Toxicity

870.3100 90

- Day Oral Toxicity

– Rat MRID 00043624

In a subchronic oral toxicity study (MRID 00043624), 1

- naphthaleneacetic acid, technical (Lot # not reported; purity not reported) was administered, in the diet, to Sprague Dawley rats (20/sex/dose) at dose levels of 0, 50, 150 or 300 mg/kg bw/day for 13 weeks. Two additional group of 10 rats/sex were administered 0 or 300 mg/kg bw/day and sacri ficed after 30 days and necropsied. All rats survived except for one death in the control group. No abnormal behavior or toxic effects were observed in the treated rats. Fluctuations in food consumption occurred in control and treated groups. Body weig hts in males and females of the high dose group were depressed particularly in the females where they gained only one third of the body weight achieved by the controls. All hematologic values were within the reference limits. Hematocrit, hemoglobin, and/ or RBC values in the mid and high dose males and females were slightly reduced, but considered not compound related. Alkaline phosphatase in the high dose group was elevated, probably associated with the rate of body growth. Urinalysis values were compar ablePage 56 of 79

in all groups. There were no visible macroscopic lesions in male rats except for one control male with enlarged spleen and liver and red, depressed areas in the stomach. In the females, clear fluid in the uterus (hydrometra) was noted in 3 controls, 2 low

- dose, 7 mid

- dose and 5 high

- dose. These and other lesions (ovarian cyst in one mid dose female, focal omental fat necrosis in one high dose female, one neocortical cyst in another high dose female) observed were considered not be compound induced. The absolute and relative liver weight in the high dose females appeared to be significantly increased with no histopathological findings.

It was concluded that the LOAEL for toxic effects in this study is 300 mg/kg/day based on decreased body weight in both sexes and enlarged liver weights in females. The NOAEL is 150 mg/kg/day.This subchronic toxicity study in the rat was conducted prior to the current testing guidelines.

870.3100: 90

- Day Oral Toxicity

- Rat MRID 43896001

In a subchronic toxicity study (MRID 43896001), 1

- Naphthaleneacetamide (Lot # I940415; 98.7% a.i.) was administered to CRL:CD BR rats (10/sex/dose) by feeding at dose levels of 0, 250, 1,000, or 4,000 ppm (mean measured concentrations of 0, 19.1, 73.8, or 292.1 mg/kg/day

for males and 0, 20.4, 81.5, or 313.5 mg/kg/day for females) for 90 days. In the 4,000 ppm treatment groups, mean body weights were lower for males (10

- 15%) and females (9

- 12%) throughout the study, compared to controls. Final mean body weight gains were lower fo r males (14%) and females (20%). In addition, food consumption was consistently reduced for males (11

- 28%) and females (2

- 20%) throughout the study. Mean relative liver weights were significantly increased in both 4,000 ppm males (14%; p  0.05) and female s (32%; p  0.01) with accompanying histopathological changes consisting of enlarged (hypertrophied) centrilobular hepatocytes with an abundance of fine granular eosinophilic cytoplasm. No rats died during the study. No treatment

- related differences in cli nical appearance, ophthalmology, hematology, clinical blood chemistry or urinalysis parameter or gross pathology were observed in any treatment group. No neoplastic tissue was observed in any of the treatment groups.

The LOAEL is 4,000 ppm (292.1 mg/kg /day), based on decreased body weight, reduced body weight gain, reduced food consumption, and increased relative liver weights with histopathological changes in both sexes. The NOAEL is 1,000 ppm (73.8 mg/kg/day). The study is classified as Acceptable/Gu ideline.

870.3100: 90

- Day Oral Toxicity

- Rat MRID 42932601

In a 90 day oral (diet) toxicity study (MRID 42932601), male and female Crl:CDBR (Sprague

Dawley) rats (10/group/sex) received 1

- Napthaleneacetic Acid Sodium Salt (Lot # 214001; 96.44% purity) either 0, 200, 2000, or 8000 ppm (equivalent to 13.9, 136.6, and 564.9 mg/kg/day for males and 15.2, 149.3, and 583.4 mg/kg/day for females, respectively) for 13 weeks. Dose

levels were based on a 14

- day dietary study with 1

- Na

- NAA, no information was pr ovided. No clinical toxicity or mortality related to the treatment was reported in any of the groups. The absolute body weights for both sexes in the high dose groups were statistically significantly different from control from day 7 for males and day 14 for females, approximately 18 to 20 %Page 57 of 79

lower than control for both sexes at the end of 90 days. Systemic toxicity was noted at 2000 ppm and above based on statistically significant (p<0.05

- p<0.01) decreased hematocrit and hemoglobin, increased liver weig hts and vacuolation of the periportal hepatocytes along with hypertrophy of the cells of the adrenal cortex zona glomerulosa in females and increased kidney weights in males. Further, at the 8000 ppm dose group there were decreased body weight gains (25

- 3 0% decrease), decreased food consumption and decreased food efficiency along with decreased red blood cell parameters, platelet counts, total serum protein and albumin. The liver and kidney weights (absolute and relative to body weight) were increased in high dose males and females along with hepatocellular hypertrophy (4/10 in high dose males and females) and vacuolation of the periportal hepatocytes (10/10 in mid and high dose females) and hypertrophy of the cells of the adrenal cortex zona glomerulosa ( 6/10 in the mid dose females and 7/10 in the high dose females, and 3/10 in high dose males) and urinary bladder mucosa (9/10 in high dose males and 7/10 in high dose females).

The LOAEL for systemic toxicity is 2000 ppm (136.6 mg/kg/day for males and 1 49.3 mg/kg/day for females) with a NOAEL for systemic toxicity of 200 ppm (13.9 mg/kg/day for males and 15.2 mg/kg/day for females) based on decreased hematocrit and hemoglobin, increased liver weights and vacuolation of the periportal hepatocytes along wi th hypertrophy of the cells of the adrenal cortex zona glomerulosa. The study is classified as Acceptable/Guideline.

870.3100: 90

- Day Oral Toxicity

- Rat MRID 43896002

In a subchronic oral toxicity study (MRID 43896002), 1

- naphthaleneacetic acid, ethy l ester (Lot # AM 315002; 100% ai) was administered, in the diet, to CRL:CD BR rats (10/sex/dose) at dose levels of 400, 2000 or 8000 ppm for 13 weeks. The actual average doses at the end of the study were 19

- 25 mg/kg/day for the 400 ppm group, 92

- 123 mg/k g/day for the 2000 ppm group,

and 388

- 519 mg/kg/day for the 8000 ppm group, for males and females, respectively. Lower body weight, body weight gain, food consumption and food efficiency were observed for the 8000 ppm males and females compared to the co ntrols. Body weights for the males were 7

- 13%

lower and for the females were 9

- 21% lower than the corresponding controls throughout the study. Body weight gains were significantly reduced for both sexes at various weekly intervals throughout the study, a nd by the end of the study, were 18 and 38% lower for males and females, respectively, than the control gains. Mean food consumption by the males and females was 5

- 11

and 15

- 22 lower, respectively, than the control values for most weekly intervals; decrea sed food efficiency for both sexes was observed at most weekly intervals. Increased relative and/or absolute liver and kidney weights were observed for the 2000 and 8000 ppm treatment groups. Relative liver weights were 21% higher for the 2000 ppm female s and 20 and 58% higher for the 8000 ppm males and females, respectively, compared to the control weights. Absolute liver weights were 13 and 24% higher for the 2000 and 8000 ppm females, respectively, compared to the controls. Relative kidney weights we re higher for both sexes from the 2000 ppm (11% higher) and 8000 ppm (17

- 23% higher) treatment groups. Absolute kidney weight for the 2000 ppm males was 16% higher than the controls but was not increased for the 8000 ppm males. No associated macroscopic or microscopic changes were observed in the livers and kidneys of rats from any treatment group. Decreased red blood cell counts, hemoglobin, and hematocrit for bothPage 58 of 79

sexes from the 2000 and 8000 ppm groups were not considered clinically significant, but

a ppeared to be treatment

- related since they were dose

- dependent. The 8000 ppm males and females also exhibited increased total bilirubin (19

- 21% higher) in conjunction with reduced red blood cell counts, hemoglobin, and hematocrit. No other treatment

- rela ted effects were observed during the study. No rats died during the study. No differences in clinical signs, ophthalmology, macroscopic or microscopic pathology were observed between any of the treatment and control groups. Decreased urine protein in th e 2000 and 8000 ppm males was not observed in the corresponding females.

The LOAEL for this study is 8000 ppm (594 mg/kg/day) for male and female rats, based on lower body weight, suppressed body weight gain, and reduced food consumption as compared to the controls. Absolute and/or relative liver and kidney weights for both sexes were seen at this dose but were not accompanied by any macroscopic or microscopic changes, however, males and females at this dose also exhibited increased total bilirubin (19

- 21% higher) in conjunction with reduced red blood cell counts, hemoglobin, and

hematocrit. The NOAEL is 2000 ppm (144 mg/kg/day) for both sexes. The study is classified as Acceptable/Guideline.

870.3150: 90

- Day Oral Toxicity

- Dog MRID 00136446

In a subchronic oral toxicity study (MRID 00136446), 1

- naphthaleneacetic acid , technical (Lot # 16388; purity not reported) was fed (gelatin capsules) to beagle dogs (4/sex/dose) at dose levels of 0, 50, 150, or 300 mg/kg/day for 180 consecutive days. Clinica l signs of toxicity were evident in the high dose group. These included anorexia lasting several days, tenderness in the mouth while dosing, icteric and pale mucous membranes, steady loss in weight, lethargy, an uncoordinated gait, dark urine, and dark st ools. Two of four males and all the females showed some or all of these effects at the end of the study. One dog had a great amount of edema in the hind legs progressing over 3 days until its legs were swollen to approximately the coxo femoral joint. Th is dog was sacrificed on day 126 of the study. Urine collected from this dog prior to sacrifice showed large amounts of bilirubin, urobilinogen and a small amount of RBC and blood.

These effects are considered to treatment

- related. The mean body weight and body weight gain was significantly depressed in the high dose females (p<0.01) at 2, 3, 4, 5 and 6 months in comparison to the control dogs. The male dogs had also reduced body weight and body weight gain during the last two months of the study. Hema tological parameters were within reference limits for the four groups. The hematology of the dog that was sacrificed showed slightly increased WBC count with a relative and absolute neutrophilia and lymphopenia which may be compound related. The clinical chemistry analysis showed that alanine amino transferase (SGPT) was elevated at 4 months (slightly) and 6 months (2x the normal value) for the high dose females. The clinical chemistry of the male dog that was sacrificed in moribund condition

showed lowe r protein, cholesterol and glucose and greatly elevated levels of total bilirubin, direct bilirubin, alkaline phosphatase, aspartate amino transferase (SGOT) and SGPT. Dose

related increases in relative weights of kidneys occurred in both males and female s of the high dose group. Dose

- related weight increases in liver, adrenals, brain and heart occurred in high dose females. The low dose group males had increased relative kidney weights and the mid dose group females had an increase in relative heart wei ghts. Histopathological examination revealedPage 59 of 79

very slight evidence of pericholangistis in the low dose group (2/8), very slight to moderate degree of hepatic insult in the mid dose group (7/8)and slight to severe degree of hepatic insult in the high dose g roup (8/8). This hepatic insult was characterized by pericholangistis, toxic degeneration of hepatocytes and hepatocellular hypertrophy in the mid dose group. Additionally centrilobular necrosis, periportal fibrosis occurred in the high dose group. A hy perplastic nodule was observed in the male dog that was sacrificed moribund. There was also evidence of squamoid metaplasi in the tracheal epithelium of 2/8 dogs and a slight degree of myocarditis (1/8) in the high dose group. Hyperkeratosis of the skin at the thoroacolumbar junction was seen in 2/8 dogs of the mid dose and 4/8 dogs of the high dose groups.

It was concluded that there was no NOAEL derived from this study. The LOAEL was 50 mg/kg/day, the lowest dose tested, based on hepatic liver chang es (pericholangistis). This subchronic toxicity study in the dog was conducted prior to the current testing guidelines.

870.3150: 90

- Day Oral Toxicity

- Dog MRID 43895901

In a subchronic toxicity study (MRID 43895901), 1

- Naphthaleneacetamide (Lot/Bat ch # I940415; 98.7% a.i.) was administered via capsule to four beagle dogs/sex/dose at dose levels of 0, 30, 100, or 300 mg/kg/day for 13 weeks. In the 300 mg/kg/day treatment group, all livers

contained accumulations of a hemosiderin

- containing pigment i n the reticuloendothelial cells and

bilirubin in the intracanalicular spaces. The spleens of 3/4 males and 2/4 females also contained hemosiderin and hematopoiesis was increased in the bone marrow in 3/4 animals of both sexes.

Decreases in red blood cell counts, hematocrit, and hemoglobin occurred in both sexes. Platelet counts and mean corpuscular volumes were increased in both sexes. Total bilirubin was increased in 1/4 males and 3/4 females, but the increases were significant (p<0.05 or 0.01) only

fo r females. Body weights were reduced in males only. Clinical signs of toxicity in both sexes were soft or liquid feces. No treatment

- related effects were observed in the 30 or 100 mg/kg/day treatment groups. No dogs died during the study. No treatment

- related differences in clinical appearance, food consumption, ophthalmology, urinalysis parameters, organ weights, or gross pathology were observed in any treatment group. No neoplastic tissue was observed in any of the treatment groups.

The LOAEL is 300 mg/kg/day, based on increased platelet count, decreased red cell parameters, and increased mean corpuscular volume which correlate with histopathological changes observed in the liver, spleen, and bone marrow in both sexes. The NOAEL is 100 mg/kg/day. The study is classified as Acceptable/Guideline.

870.3150: 90

- Day Oral Toxicity

- Dog MRID 42983801

In a 13 week oral toxicity study (MRID 42983801), 6

- month old beagle dogs (4/group/sex) received by capsule either 0, 25, 150, or 450 mg/kg/day 1

- Naphth aleneacetic Acid Sodium Salt (Lot# 214001, Purity

- 96.44% 1

- NAA & 1.79% 2

- NAA). Due to inappetence at the high dose, the feeding regimen was altered for several high dose animals to reduce excessive weight loss. Dose levels were based on a previous 6 mo nth study with Naphthalene Acetic Acid (MRID 00136446) where male and female dogs receiving 50, 150, or 300 mg/kg/day experienced severePage 60 of 79

toxicity at the 300 mg/kg/day dose. These included depressed body weight and body weight gain, histopathological chang es and mortality. In the current study with NAA sodium salt, none of the animals died. Regurgitation of intact or partially digested capsules and emesis were the

most common treatment

- related clinical sign and was toxicologically significant at the high dose. Body weight gain was significantly reduced in the high dose males (15% of controls, p<0.05) and females (29% of controls, p<0.05) accompanied by decreased food consumption and food efficiency. There were statistically significant increases in rela tive organ weight for the liver, adrenals, thyroids/parathyroids, kidneys and brain and a decrease in gonad absolute and relative weights for the high dose males. The high dose females only showed a statistically significant increase in relative kidney we ights, although the relative weights for other organs did show a tendency towards an increase. Gross examination of the genital tract revealed small prostates, small testes and epididymides in all high dose males. Microscopic examination in

these males revealed an increased incidence of hypospermatogenesis, characterized by less spermatogonia and spermatocytes and were associated with aspermia in the epididymides. These may be secondary effects to the condition of the animals, but deserve further examin ation. Systemic toxicity was noted at 150 mg/kg/day and above based on lesions of the gastrointestinal tract (ulcerative duodenitis and acute or erosive gastritis), hypocellularity of the bone marrow along with changes in liver enzymes (increased alkaline phosphatase in the high dose group), increased relative liver weights, histopathological changes of the liver (single cell necrosis, centrilobular necrosis, pigment accumulation, extramedullary hematopoiesis and mononuclear or mixed cell infiltration), de pression in erythrocyte parameters (red blood cell count, hemoglobin and hematocrit levels in high dose females with a slight similar effect in males), decreased body weight gains, food consumption and food efficiency, inappetence and emesis in the high do se

group.

The NOAEL for systemic toxicity is 25 mg/kg/day with a LOAEL for systemic toxicity of 150 mg/kg/day based on lesions of the gastrointestinal tract and hypocellularity of the bone marrow. The study is classified as Acceptable/Guideline.

870.315 0: 90

- Day Oral Toxicity

- Dog MRID 43914901

In a subchronic oral toxicity study (MRID 43914901), 1

- naphthaleneacetic acid, ethyl ester (Lot/Batch # AM 315002; 97.75% ai) was fed (gelatin capsules) to beagle dogs (4/sex/dose) at dose levels of 0, 40, 125, or 400 mg/kg/day for 13 weeks. All dogs survived the treatment.

Treatment

- related clinical signs were limited to soft or liquid feces particularly in males and to a lesser extent in females at the high dose of 400 mg/kg/day. Male dogs in the 40, 125, o r 400 mg/kg/day treatment groups had a 4

- to 5.5

- fold increase in soft/liquid feces (maximum 65 instances during 13 weeks in the 400 mg/kg/day group) compared to the control group. For females, there was one incident of soft/liquid feces in the control gr oup, five in the 40 mg/kg/day group, eight in the 125 mg/kg/day group, and 19 in the 400 mg/kg/day group during the 13

- week study. A treatment

- related lower body weight gain (20% less than the control) was seen in the males and females of the high dose gr oup. Males in the 40 or 125 mg/kg/day treatment group

were 25

- 29% heavier, and males in the 400 mg/kg/day treatment group were 20% lighter than males in the control group; all three groups consumed 19% more food than the control during the study. Female dogs in the 400 mg/kg/day treatment groups consumed 11% less food over thePage 61 of 79

course of the study. Male dogs in the 40, 125, or 400 mg/kg/day treatment groups had significantly (p <0.05 or 0.01) lower red blood cell, hemoglobin, and hematocrit levels, and

l ower mean platelet volumes (MPV) than the controls throughout the study. In the high dose males at 12 weeks, these were 18%, 17%, 17% and 22% lower than the controls for RBC, hemoglobin, hematocrit and MPV levels, respectively. Although, these parameters were within the historical range values for this dog type, they were at the lower end of the range and may suggest anemic affects caused by the administration of this material at this dose. Low white blood cell counts in female dogs in the 125 or 400 mg/ kg/day treatment groups after 12 weeks of treatment were also within expected biological ranges. No other treatment

- related responses were observed during the study. No differences were observed in clinical blood chemistry, ophthalmology, urine volume or chemistry, organ weights, or macroscopic or microscopic organ morphology between dogs in the treated and the control groups. No neoplastic tissue was

observed.

The LOAEL for this study is 400 mg/kg/day, based on soft/liquid feces and the depressed

bod y weight gains of male and female dogs at this treatment level. Additionally some blood parameters (RBC, hemoglobin, hematocrit and mean platelet volume) were all depressed in the male dogs at this level. The NOAEL was 125 mg/kg/day. The study is classif ied as Acceptable/Guideline.

870.3200 21

- day Dermal Toxicity Study MRID 43581001

In a repeated dose dermal toxicity study (MRID 43581001), 1

- Naphthaleneacetamide (Lot # I940415; 98.71% ai) was applied to the shaved skin of Crl:CD BR rats (5/sex/dose) at dose levels of 0, 100, 300, or 1000 mg/kg for 6

- 6.5 hours/day, 5 days/week, for 3 weeks. No

treatment

- related effects were observed at any dose level. There were no clinical signs of toxicity, and body weights, body weight gains, and food consumption we re similar between the treated and control groups. No differences were observed in hematology parameters or clinical blood chemistry. Skin irritations occurred at similar rates in rats in all groups. Although males in the 1000 mg/kg treatment group had absolute liver weight which was 16.4% heavier (p <0.05) than the control, no accompanying anatomical or functional changes were observed, and the mean liver weights of females in the 1000 mg/kg treatment group were lower than the control.

No other differe nces in the organ weights and no differences in macroscopic or microscopic organ morphology were observed between rats in the treated and the control groups. No neoplastic tissue was observed at any dose level. Ophthalmoscopic examinations and urinalysis were not performed during the study.

No LOAEL was established. The NOAEL was the highest treatment level, 1000 mg/kg body weight. The study is classified as Acceptable/Guideline.

870.3200 21

- day Dermal Toxicity Study MRID 43134701

In a 21 day dermal toxicity study (MRID 43134701), male and female Crl:CDBR rats (5/group/sex) received either 0, 100, 300, or 1000 mg/kg/day 1

- Naphthaleneacetic Acid Sodium Salt (96.44% 1

- NAA & 1.79% 2

- NAA) applied to clipped, unabraded dorsal surface of the skin,Page 62 of 79

5days/we ek for 3 weeks. Doses were based on a 7

- day dermal range finding study in rats where no overt signs of toxicity or dermal irritation was noted at doses of 250, 500 and 1000 mg/kg/day.

No treatment

- related or clinical signs of systemic toxicity were obse rved in any of the treatment groups. Slight decreases in absolute body weight of high dose animals were not statistically or biologically significant despite reduced body weight gain (76.3% of the controls in the males and 71.2% of the controls in females) and food efficiency. Accordingly, these effects were not considered adverse. Dermal toxicity was noted in the high dose group as microscopic changes of the skin of the treated areas. These changes included minimal to slight hyperplasia of the sebaceous g land and minimal to slight hyperplasia and hyperkeratosis of the epidermis.

The systemic LOAEL was not established. The systemic NOAEL is 1000 mg/kg. The dermal LOAEL is 1000 mg/kg based on microscopic changes in the skin (slight hyperplasia

of the seb aceous gland and minimal to slight hyperplasia and hyperkeratosis of the epidermis). The dermal NOAEL is 300 mg/kg.

This study is classified as Acceptable/Guideline and satisfies the guideline requirement for a

28

- day dermal toxicity study (OCSPP 870.320 0; OECD 410) in the rat.

870.3200 21

- day Dermal Toxicity Study MRID 43581002

In a repeated dose dermal toxicity study (MRID 43581002), 1

- naphthaleneacetic acid, ethyl ester (Lot # 315002; 97.75% ai) was applied to the shaved skin of Crl:CD BR rats (5/sex /dose) at dose levels of 0, 100, 300, or 1000 mg/kg for 6

- 6.5 hours/day, 5 days/week, for 3 weeks.

For all treatment groups, there were no clinical signs of toxicity, and body weights, body weight gains, and food consumption were similar to the controls. There were no differences in hematology parameters, clinical blood chemistry, organ weights, or macroscopic or microscopic organ morphology between rats in the treated and the control groups. No neoplastic tissue was observed. Ophthalmoscopic examinatio ns and urinalysis were not performed during the study.

Treatment

- related dermal irritation was seen in the treated skin of all animals exposed to 1

- Naphthaleneacetic acid ethyl ester. As the dose level was increased, the incidence and/or severity of epid ermal hyperplasia and hyperkeratosis, sebaceous gland hyperplasia, and dermal inflammation in skin from the treated areas increased in the treated rats compared to the controls. In general, the severity of the reactions increased from minimal/slight to sl ight/moderate with increasing dose rate. No systemic responses were observed.

The LOAEL for systemic toxicity is >1000 mg/kg/day and the NOAEL for systemic toxicity is 1000 mg/kg/day. The LOAEL for dermal irritation is 100 mg/kg, based on the presence

of treatment

- related dermal irritation in the treated skin of rats in the 100, 300, and 1000 mg/kg treatment groups. No NOAEL for dermal irritation was established. The study is classified as Acceptable/Guideline.Page 63 of 79

A.4.2 P renatal Developmental Toxicity

8 70.3700a: Prenatal Developmental Toxicity Study

- Rat MRID 00042765

In a prenatal developmental study (MRID 00042765), NAA technical (Lot # NAA 73323G; purity not reported, white powder) was administered by gastric intubation to groups (24/group)

of heal thy timed pregnant albino CD rats at dose levels of 0, 10, 50 or 250 mg/kg/day in 0.05% sodium carboxymethylcellulose from days 6 through 15 of gestation. The dams were observed daily for signs of toxicity and weighed on day 1, 3, 6

- 15, 17 and 20 of gesta tion. On day 20 of gestation the dams were euthanized with ether and the ovaries and uterine contents were immediately examined for viable and nonviable fetuses, resorptions, number of implantations, and number of corpora lutea. Fetuses were examined for visceral and skeletal anomalies using proper techniques. No deaths or toxic symptoms were reported at any dose level. There was a statistically significant decrease in the mean body weight gain in the 250 mg/kg/day rats with the onset of the compound a dministration. The dams in the 10 and 50 mg/kg/day groups did not show significant decrease in body weight gain during compound administration but showed a decrease compared to the controls from days 17

- 20. Litter size and fetal loss were not affected by the treatment. A slight decrease (statistically insignificant) in mean litter size (9.3, 9.3, 8.8 and 7.9 in the control, low

- , mid

- , and high

- dose groups, respectively) was considered unrelated to treatment. There was a statistically increased (p<0.05) mean preimplantation loss in the mid

and high dose groups (38.1

- 42.6%) in comparison to the control animals (20.6%). However the means were within the range of the individual values of the control animals and were considered

not treatment related. The i ncidence of major malformations and minor anomalies were comparable in all groups.

The developmental LOAEL is >250 mg/k/day and the NOAEL is 250 mg/kg/day. The maternal toxicity LOAEL 250 mg/kg/day based on decreased body weight gain during the

compou nd administration and the NOAEL for maternal toxicity is 50 mg/kg/day. The study is classified as Acceptable/Guideline.

870.3700a: Prenatal Developmental Toxicity Study

- Rat MRID 46685803

In another developmental toxicity study (MRID 46685803), 1

- Naph thaleneacetic acid sodium salt (97.4% a.i., batch/lot # 014

- S0401

- 001) was administered to 24 female SD (Wistar

- derived) rats/dose by gavage at dose levels of 0, 15, 50 or 150 mg/kg bw/day from days 5 through 21 (inclusive) of gestation. All animals survi ved the duration of the study and all were pregnant

with live fetuses in utero at scheduled termination on day 22 of gestation. There were no

treatment

- related clinical signs. Cesarean section data did not reveal any differences among all groups includin g the controls. Maternal body weights of the 150 mg/kg/day females adjusted for initial weight were statistically significantly (p<0.01) lower than the control group from day 6 through day 17. For the 50 mg/kg/day females body weights were lower during t he first 4 days following the test material administration. Females in the low dose groups were not affected. Body weight gains were lower following the first day of treatment and recovered completely on the second day (low

- dose group) and third day of tre atment for the mid

- and high

- dose groups.Page 64 of 79

Sporadic lower food consumption occurred in the mid

- and high

- dose groups. Although the lower body weights seen in the high and mid dose groups were statistically significant, these are considered not to be biologi cally significant or adverse since these changes were only 1

- 4%

lower than the controls. T he maternal LOAEL is >150 mg/kg bw/day, and the maternal NOAEL is 150 mg/kg bw/day (highest tested dose).

A treatment

- related effect at the high dose resulted in red uced mean fetal weights of male and female fetuses. The only notable visceral anomaly was increased slightly dilated ureters with statistical significance in the mid (p<0.05) and the high doses (p<0.01). There were no treatment

related external malformati ons or variations of the fetuses. Minor treatment

- related skeletal malformations were seen at the high dose of 150 mg/kg/day. These included an increased number of unossified centrum 5, increased number of cervical arch 7 cartilage fused to arch 6

cartil age, increased interruptions of thoracic rib 10 costal cartilage, increased number of long length cervical rib. A treatment

- related increased incidence of fetuses but not litters with a

shortened 7 th cervical rib was observed in the 50 and 150 mg/kg/day g roups. The incidence of both fetuses and litters with an ossified calcaneum was lower than in the control group and indicated a reduction in ossification, in the 150 mg/kg/day group. Reduced ossification of the mania and pes was seen at the high dose. A statistically significant higher mean score for the pes was reported for the 50 mg/kg/day group, but the difference from the control mean was minimal.

The developmental LOAEL is 150 mg/kg bw/day, based on decreased fetal weight and minor skeletal changes (centrum 5 not ossified, cervical arch 7 cartilage fused to arch 6 cartilage, shortened 7 th cervical rib). The developmental NOAEL is 50 mg/kg bw/day. The study is classified as Acceptable/Guideline.

870.3700b: Prenatal Developmental Toxicity Study

- Ra bbit MRID 00137821

In a prenatal developmental study (MRID 00137822), NAA (Lot # RTS2846AC; 98.55% purity) was administered by oral gavage to groups (16/group) of artificially inseminated Dutch Belted rabbits (4 1⁄2 to 5 months old) at dose levels of 0, 37.5, 75, or 150 mg/kg/day from days 6 through 27 of gestation. These doses were selected on the basis of a range finding study (MRID 00137821) where groups (5 rabbits/group) were dosed NAA once daily by gavage at dose levels of 0, 28, 80 or 240 mg/kg/day from days 6 through 27 of gestation. Animals were observed twice daily for mortality and once daily for toxic signs during the dosing period. Animals that died were necropsied. Body weights were taken on days 0, 6, 12, 18, 24 and 28. Surviving

animals were sacrificed on day 28 and the uterus and ovaries were examined for viable and nonviable fetuses, resorptions, number of implantations, and number of corpora lutea. One animal in the range finding study dosed at 240 mg/kg/day aborted on GD 28 following signs of toxicity consisting of hair loss, decreased feces and significant weight loss. In the main study, one low dose animal died on GD 25 and three high dose gravid animals died during the study on GD 20, 22 and 27. Only two of the high dose animals showed signs of toxicity (hair loss on the forelimbs, clear or white nasal discharge with dried material around the nose, decreased defecation and dry red material, presumably died blood, beneath the cage) prior to death. Necropsy observations of the dead animals showed foamy fluid or congested lining in thePage 65 of 79

trachea, congested lungs, fluid in the thoracic and/or abdominal cavities, reddening and/or erosions on the stomach mucosa, mucoid material or fluid in the intestines and pale liver or pitted kidneys. Weights of the pregnant animals varied over the gestation period with some indication of treatment related loss in the high dose. No compound

- related abnormalities were observed in the pregnant animals at necropsy. No compound

- related effect was observe d on implantation or fetal viability. However, in the range finding study, an increase in the mean preimplantation loss (23.2% at the low dose to 42.1% at the high dose compared to 11.4% in the concurrent control) occurred at all doses in the treated anim als and appeared to be treatment related. However, this increased preimplantation loss was considered problematic by the EPA reviewer since historical control data on 343 animals showed a preimplantation loss of 30.8%.

Examination of the fetuses derived from the main study did not reveal any developmental

effects.

The maternal toxicity NOAEL is 75 mg/kg/day based on lethality at the LOAEL of 150 mg/kg/day. The developmental and fetotoxic NOAEL was 150 mg/kg/day based on lack of developmental and fetoto xic effects at the highest dose of 150 mg/kg/day tested. The study is classified as Acceptable/Guideline.

870.3700b: Prenatal Developmental Toxicity Study

- Rabbit MRID 46685801

In another developmental toxicity study (MRID 46685801) 1

- Naphthaleneacetic acid sodium salt (97.4% a.i., batch/lot # 014

- S0401

- 001) was administered to 24 female New Zealand White rabbits/dose in water by gavage at dose levels of 0, 30, 100 or 300 mg/kg bw/day from days 5 through 29 (inclusive) of gestation. All animals survive d the duration of the study except for one rabbit at the high dose which died on GD 22 due to a dosing error and one control rabbit was sacrificed on GD 24 following accidentally biting the dosing catheter into its esophagus. A

treatment related reduction in body weight and body weight gain was noted following the initial

oral administration of 1

- NAA Na salt to pregnant rabbits at the high dose of 300 mg/kg/day. This was accompanied by initial reduction in food consumption. Final body weights were

compar able in all treatment groups. Several dams receiving this dose were observed with few/no feces during the study. Post mortem examination revealed red/black spots/areas in the glandular mucosa of the stomach in several of these dams indicating local irrit ation by the test material. No adverse effects were noted in the dams at the lower dose of 30 and 100 mg 1

- NAA Na salt /kg/day. Cesarean section data did not reveal any statistically significant differences among all groups including the controls.

The LOAEL for maternal toxicity is 300 mg/kg/day based on reduced body weight, body weight gain and reduced food consumption, clinical signs (few/no feces) and stomach irritation (red/black spots/areas in the glandular mucosa of the stomach). The maternal

to xicity NOAEL of 1

- NAA Na in pregnant rabbits derived from this study is 100 mg/kg/day.

Developmental Toxicity. The oral administration of 1

- NAA Na salt during gestation to rabbits resulted in decreased mean fetal weights (males and females) at the hig h dose of 300 mg/kg/day.Page 66 of 79

Mean fetal weights at the low

- and mid

- dose were comparable to the control group. There was no effect by l

- NAA

- Na salt administration on the overall incidence of major external/visceral,
skeletal or Bouin’s head defects or on the incidence of any specific major fetal abnormalities. The defects were considered to be spontaneous in origin. Fetuses with minor defects of the head following Bouin’s fixation and sectioning, and fetuses with minor external/visceral defects were comparable in all groups including the control. There was no indication that any of the specific effects were attributable to the test material. Fetuses with minor skeletal defects were statistically significantly higher in the 300 mg/kg/day. However, only one spe cific defect (dumbbell shaped

ossification of the 7 th thoracic centrum) was statistically significantly higher (p<0.01) in the 300 mg/kg/day group in comparison with the control group. No variants were detected in the heads of the fetuses following Bouin’ s fixation and serial sectioning and no external/visceral findings were detected in any fetus. The overall proportion of fetuses with skeletal variants was statistically significantly higher in the 30, 100 and 300 mg/kg/day groups in comparison with the

c ontrol group, but there was no specific increase in any specific variant and is not attributable to

the test material administration. The incidence of lengthened costal cartilage of the 10 th thoracic rib was statistically significantly higher in all group s administered 1

- NAA

- Na in comparison with the control group, although there was no evidence of a dose

- related trend. However, the incidences of fetuses with shortened or lengthened 13 th thoracolumbar ribs (i.e. extra ribs) and with 27 bilateral pre

- pelvic vertebrae were statistically significantly increased in the 300 mg/kg/day group in comparison with the control group and were considered to be attributable to

1

- NAA

- Na administration.

The LOAEL for developmental toxicity is 300 mg/kg/day based on an in crease in the overall incidences of fetuses with minor skeletal defects and variants (dumbbell ossification

of the 7 th thoracic centrum, extra thoracolumbar ribs and 27 pre

- pelvic vertebrae) and a decrease in ossification of the manus. The NOAEL is 100 mg /kg/day. The study is classified as Acceptable/Guidelines.

A.4.3 Reproductive Toxicity

870.3800: Reproduction and Fertility Effects

- Rat MRID 43796301Page 67 of 79

In a 2

- generation reproduction study (MRID 43796301) 1

- Na

- NAA (Lot # 214001; 96.44% a.i.)

was admini stered to 35 Crl:CD ® BR, rats/sex/group in diet at dose levels of 0, 100, 1000 and 3000 ppm [0, 7, 69 and 210 mg/kg/day for males and 0, 8, 81 and 239 mg/kg/day for females, respectively]. The dose levels were selected on the basis of previous toxicity stu dies in rats. At 3000 ppm (HDT), treatment

- related decreases in body weight gain and food consumption were

observed in the P 1 and P 2 females during premating and gestation periods and decrease in body weight gain in P 2 males during the premating period. Reductions in P 2 male and female premating body weight gain, although appearing systemic in nature may have been secondary to developmental toxicity in these animals. Reduced survival and growth were observed in both F 1 and F 2 offspring. No adverse effec ts were noted at  1000 ppm.

Systemic and reproductive/developmental LOAEL = 3000 ppm (210 mg/kg/day for males, 239 mg/kg/day for females), based upon reduced body weight gain and food consumption in parental animals and reduced litter survival, and pup weight throughout lactation in both generations of offspring. Systemic and reproductive/developmental NOAEL = 1000 ppm (69 mg/kg/day for males, 81 mg/kg/day for females). The study is classified as Acceptable/Guideline.

A.4.4 Chronic Toxicity

870.4100a: Chronic Toxicity

– Rat MRID 44157501 In a combined chronic toxicity/oncogenicity study (MRID 44157501), 1

- Naphthaleneacetic

acid sodium salt (1

- Na

- NAA) (96.44% 1

- NAA; 1.79% 2

- NAA w/w; Lot no. 214001) was

administered to Crl:CD ® BR rats (80/sex/dose) in t he diet at concentrations of 0, 100, 1000, or 5000 ppm (corresponding to 0, 4.4, 43.8, and 224.5 mg/kg/day for males and 0, 5.6, 55.8, and 303.6 mg/kg/day for females). An interim sacrifice was performed at 12 months on 20 rats/sex/dose; terminal sacrific e (main study) was after 20.5

- 23 months due to the high mortality and poor health in the treated and control groups. There were no treatment

- related effects on survival or clinical observations. High

- dose females had lower mortality than the controls (p  0.05). Weekly body weights of the high

- dose males were significantly lower for days 14

- 119

and 238

- 259 (  8.8%; p  0.05 or 0.01), but their overall weight gain was similar to that of the

controls. The low

- and mid

- dose females’ weekly body weights and overall weight gains were within 7.4% and 14% of controls, respectively (p  0.05 or 0.01). High

- dose females, however, had lowered weekly body weights (  35%; p  0.01), total weight gain (61% of controls), and overall food consumption and efficiency (1 5% and 36% lower than controls, respectively). Serum triglyceride levels were about 50% lower than control levels at 6 and 12 months in high

dose males, and were 66

- 78% lower at 12 and 18 months in high

- dose females (p  0.05 or 0.01). The urine protein content of high

- dose females was decreased from 12 months to terminal sacrifice to only 4.1

- 6.1% of control values (p  0.05 or 0.01). These clinical chemistry changes had no histopathological correlates and their toxicological significance is unknown. H igh

- dose males and females had a significantly increased incidence and severity of stomach mucosal gland dilation (p  0.05). The incidence of focal alveolar macrophages (in some cases accompanied by focal chronic inflammation) was increased in mid

- and h igh

- dose females, and was correlated atPage 68 of 79

the high dose with an increased incidence of grossly observed lung nodules (p  0.05 or 0.01). The incidence of focal alveolar macrophages was also slightly increased in high

- dose males (p = 0.071).

The LOAEL is 5000 ppm (224.5 mg/kg/day for males and 303.6 mg/kg/day for females), based on an increased incidence of stomach (mucosal gland dilation) and lung lesions (focal alveolar macrophages) in both sexes of rats, and on lowered body weight gain and food

efficien cy in females. The corresponding NOAEL is 1000 ppm (43.8 mg/kg/day for males and 55.8 mg/kg/day for females). The only neoplastic finding (p  0.01) was an increased incidence of uterine endometrial stromal polyps in high

- dose females (2/60, 1/60, 3/60, 13/60 at 0, 100, 1000, 5000 ppm, respectively). The longer survival time of the high

- dose females (about 88 days) did not account for the greater incidence of these benign neoplasms. The study is classified as Acceptable/Guideline.

870.4100b: Chronic To xicity

- Dog MRID 43744201

In a chronic toxicity study (MRID 43744201), 1

- napthaleneacetic acid, sodium salt (Lot # 214001; 96.44% ai) was administered (gelatin capsules) to beagle dogs (4/sex/dose) at dose levels of 0, 15, 75, or 225 mg/kg/day for 52 wee ks. At 225 mg/kg/day, Na

- NAA administration resulted in gross pathological changes in the stomach of one male and one female and histopathological change in the stomachs of four males and one female. The latter were characterized by mucosal atrophy (3) an d congestion (1) in males and hemorrhaging in the female. Slight sinusoidal histiocytosis was observed in the livers of four males and three females. Both males and females exhibited a high incidence of emesis and capsule regurgitation at the 225 mg/kg/d ay dose level. At 75 mg/kg only males exhibited dose

- related toxic response

to Na

- NAA as characterized by stomach lesions in three animals consisting of necrosis of the fundic or pyloric epithelium and by slight sinusoidal histiocytosis in the liver of tw o males. No

other definitive treatment

- related changes were noted in organ weights or gross pathological changes. All microscopic tissue abnormalities, other than those mentioned, occurred randomly and sporadically in all study groups. No neoplastic tiss ue was observed in beagles in the treatment or control groups. No dogs died during the study. No treatment

- related differences were observed between the clinical appearance, body weights, food consumption, biochemistry, hematology, urinalysis, or ophthal mology of the treated and control animals.

The LOAEL is 75 mg/kg/day in males and 225 mg/kg/day in females, based on emesis, capsular regurgitation incidences, gross and histopathologic changes in stomachs, and sinusoidal histiocytosis in livers. The NO AEL is 15 mg/kg/day in males and 75 mg/kg/day in females. The study is classified as Acceptable/Guideline.

A.4.5 Carcinogenicity

870.4200a: Carcinogenicity Study

- Rat MRID 44157501

This study is described above in the chronic studies section. An increased incidence of uterinePage 69 of 79

endometrial stromal polyps occurred in female rats at 303 mg/kg/day dietary feeding of Na NAA for two years. According to HED consulting pathologist, Dr. John Pletcher these are considered to be benign proliferative lesi ons of no carcinogenic concern (email to William Burnam of HED on 04/04/2002). Na NAA was not carcinogenic in the rat.

870.4200b: Carcinogenicity (feeding)

- Mouse

There is an NCI study published in 1969 where NAA acetamide was tested at one dose (maxi mum tolerated dose: according to the published article) as part of a testing program of 120 compounds. Only the preliminary results were published (Innes et al , Innes JR, Ulland BM, Valerio MG, Petrucelli L, Fishbein L, Hart ER, Pallotta AJ, Bates RR, Fal k HL, Gart JJ, Klein M, Mitchell I, Peters J. 1969. Bioassay of pesticides and industrial chemicals for tumorigenicity in mice: a preliminary note. J. Natl Cancer Inst. 42: 1101

- 1114). The test materials were administered to two hybrid strains of mice : C57BL/6 x C3H/Anf and C57BL/6 x AKR (18/sex/hybrid strain). The mice were administered NAA acetamide at one week of age by stomach intubation at 464 mg/kg/day until weaning at 4 weeks of age and administered the NAA acetamide in the diet at 1298 ppm (eq uivalent to 195 mg/kg/day at the conversion rate of 0.15 mg/kg for 1ppm) for approximately 18 months. Gross and histopathologic examination of the mice at the end of the feeding period did not reveal a significant increase in tumors over the

controls.

87 0.4200b: Carcinogenicity (feeding)

- Mouse MRID 46685802

In a carcinogenicity study (MRID # 46685802), Naphthaleneacetic Acid Sodium Salt (97.4%,

batch/lot # 014

- S0401

- 001) was administered to 50 C57BI/10J f CD

- 1 Alpk mice/sex/dose in the

diet at dose level s of 0, 100, 500, or 2500 ppm [equivalent to 0, 10.8, 53.3, 276.0 / 0, 14.3, 70.9, 348.7 mg/kg bw/day M/F, respectively] for at least 80 weeks. There were no statistically significant differences in survival or clinical signs between treated groups and co ntrols in either sex. At the top dose (2500 ppm), bodyweights in males and females were statistically significantly lower than controls throughout the study with a maximum effect of 11% at week 77 in males, and 5% in females at week 41. Food consumption in males and females at this dose level was statistically significantly lower than controls at some time points throughout the study while food utilization in males was statistically significantly lower than controls in weeks 1

- 4

and overall in weeks 1

- 13. T otal white blood cell, monocytes and large unstained cell counts were statistically significantly higher than controls in females at the top dose. This apparent elevation is due to higher counts in 2 individual animals and is considered to reflect animals with lymphomas in which there is also a leukemic response. This effect was not compound

- related. Also, at the top dose, liver and kidney weights in both sexes and epididymis in males were statistically higher than controls while brain weights in males were statistically lower. Masses in the liver were identified in 3 male rats at the top dose, and in one female at 100 ppm. Pancreatic masses were also identified in 2 females at 2500 ppm and in 1 female at 500 ppm. A four

- fold increase, compared to controls, in the incidence of hepato

- cellular vacuolation in the liver was observed in males dosed at 2500 ppm. A slight increase in the presence of mononuclear cell

infiltration in the liver was also observed in both males and females at this dose level. AnPage 70 of 79

increa se in the incidence of intratubular microlithiasis and tubular basophilia within the kidney was observed in females and an increase in interstitial mononuclear cell infiltration in the kidney of males at 2500 ppm. There was an increase in the incidence of marked degeneration in the testes in males dosed with 2500 ppm of compound. Associated with this change, there was an increase in the incidence of decreased spermatozoa within the epididymis and dilated rete within the testis. At 2500 ppm, adenomas of the liver were observed in one male rat, and adenomas of the lung were observed two males. Adenocarcinomas of the liver were observed in one control male and two males given 2500 ppm. None of these changes achieved statistical significance.

There was a statis tically significant increase in the incidence of histiocytic sarcoma in females at 2500 ppm but it was within historical control levels. There was a statistically significant increase (overall) in the incidence of multiple tumors in females given 2500 ppm. However there was no statistically significant increase in any individual tumor type, the incidence was low, and there

was no dose

- response relationship. Therefore this difference was considered not to be compound

related.

The LOAEL is 2500 ppm [ 276 (M ), 348.7 (F) mg/kg/day], based on lower body weight, food consumption, increased liver and kidney weights in both sexes and epididymis in males, lower brain weights in males, hepato

- cellular vacuolation in males, adenomas of the liver and lung in males, in crease in the incidence of multiple tumors in females. The NOAEL is 500 ppm [ 53.3 (M), 70.9 (F)] mg/kg/day. At the doses tested, there was no treatment related increase in tumor incidence when compared to controls. The study is classified as Acceptable/G uideline.

A.4.6 Mutagenicity

Gene Mutation

GLN 870.5100

, MRID 43581006: NAA

Acetamide

MRID 00042761 & 00042762:

NAA MRID 43581004: NAA Ethyl

Ester No mutagenic effect was noted with or without microsomal activation at concentrations up to the toxic r ange of 5000 micrograms/plate in the initial tests or in the confirmatory

assay.

Chromosomal Aberrations

GLN 870.5395

MRID 43581005 NAA

Acetamide

MRID 00042763 NAA MRID 43581003 NAA Ethyl

Ester In Vivo Mammalian Cytogenetics

- Erythrocyte

Micronucleus Assay in Mice. There was no indication that NAA technical or the acetamide or the ethyl ester induced a clastogenic or aneugenic effect in either sex at any dose or

sacrifice time.Page 71 of 79

GLN 870.5300

MRID 43580202: NAA

Acetamide MRID 43580201: NAA Ethyl

Es ter In Vitro mammalian cell gene mutation

- L5178Y TK+/

- Mouse Lymphoma Mutagenesis Assay. NAA acetamide was tested up to cytotoxic levels (  1250 μg/mL

- S9 and

 150 μg/mL +S9). NAA Ethyl ester was tested up to cytotoxic levels (100 μg/mL

- S9 and  300 μ g/mL +S9). Both were non mutagenic without S9 activation system, but positive with S9 activation system at or above 100 ug/mL for the acetamide and 300 ug/mL for the ethyl ester.

GLN 870.5450

MRID 00042764 NAA Rodent Dominant Lethal Assay. NAA did not produce dominant lethal effects in mice at oral doses of 125, 250 or 500 mg/kg/day as measured by pre implantation and post implantation losses

A.4.7 Neurotoxicity

There are no neurotoxicity studies available but the chronic and subchronic studies s how no evidence of neurotoxicity or neuropathology. The HED HASPOC waived the requirement for the neurotoxicity battery (TXR 0056465).

A.4.8 Metabolism

870.7485 : Metabolism

– Rat MRID 43963301

In a study (MRID 43963301) conducted to examine the metabo lism and disposition of 1

- naphthaleneacetamide , five male and five female Sprague

- Dawley rats were given either a single 1 or 100 mg/kg bw oral dose, or a 14

- day repeated dose (1 mg/kg/day). Groups of male and female rats were subjected to the dosing regi mens above using [ 14 C] ring labeled

- 1

- naphthaleneacetamide (Batch No. 94

- 516

- 38

- 10; 99.7% radiochemical purity, specific activity 55.5 mCi/mmol), and non labeled test article (Batch No. KP 0100487, chemical purity not available). Excretion, tissue distri bution, and metabolite profiles were determined. There were no biologically significant treatment

- related effects noted during the course of the study. Overall recovery of administered radioactivity was an excellent 97.2

- 101%. 1

- Naphthaleneacetamide

was readily absorbed and excreted within 36 hours following a single 1 mg/kg bw, a 14

- day repeat oral dose of 1 mg/kg bw, or a single 100 mg/kg bw oral dose. Following single or multiple oral low doses (1 mg/kg bw) of [C 14 ]

- 1

- naphthaleneacetamide, urinary excr etion accounted for

70.8

- 74.1% of the administered radioactivity suggesting that a multiple exposure regimen did not affect the absorption/excretion processes. Urinary excretion was unaffected following a single 100 mg/kg dose with 66.2

- 69.5% of the admin istered radioactivity excreted in urine. Excretion via the feces accounted for the remainder of the administered radioactivity in all treatmentPage 72 of 79

groups (21.6

- 26.2%). Excretory patterns did not exhibit gender

- related variability but reflected delayed absor ption in the high

- dose group. Because tissue burdens were very low at termination,

neither 1

- naphthaleneacetamide nor its metabolites appear to undergo significant sequestration. Both urinary and fecal metabolites were quantified by HPLC and most were i dentified using HPLC and HPLC/MS in conjunction with known standards. Urinary metabolism involved amide cleavage followed by glycine conjugation with the glycine conjugate being the major metabolite of the low and repeat doses (13.7

- 47.3% of the administe red radioactivity). The glucuronide conjugate was also a major metabolite at the low doses (4.5

- 7.0% of administered). For feces, the major metabolite detected was the dihydrodiol of naphthaleneacetamide (3.6

- 11.3% of administered. Parent compound was d etected at low concentrations (0.7

- 1.9% of administered) only in feces. Extraction efficiencies appeared to be excellent and most components in the matrices examined (urine and feces) were adequately quantified and characterized. The available data, base d upon studies using labeled 1

- naphthaleneacetamide, affirmed the metabolism pathway proposed by the investigators.

870.7485 : Metabolism

– Rat MRID 43961701

In another study (MRID 43961701) conducted to examine the metabolism and disposition of 1

- naphtha leneacetic acid, ethyl ester , male and female Sprague

- Dawley rats were given a single 1 or 100 mg/kg bw oral dose, or a 14

- day repeated dose (1 mg/kg/day). Groups of male and female rats were subjected to the dosing regimens above using [ 14 C] ring labeled

- 1

- naphthaleneacetic acid, ethyl ester (Batch No. CSL

- 94

- 516

- 33

- 25, 99.3% radiochemical purity, specific acttivity 56.2 mCi/mmol), and non labeled test article (Batch No. GAB 69

- 34

- 02, chemical purity not available). Excretion, tissue distribution, pharm acokinetic parameters, and metabolite profiles were determined. There were no biologically significant treatment

- related effects noted during the course of the study. Overall recovery of administered radioactivity was

an excellent 98.6

- 101.8%. 1

- Naphthal eneacetic acid, ethyl ester was readily absorbed and

excreted within 36

- 48 hours following a single 1 mg/kg bw, a 14

- day repeat oral dose of 1 mg/kg bw, or a single 100 mg/kg bw oral dose. Following single or multiple oral low doses (1 mg/kg bw) of [C 14 ]

- 1

- naphthaleneacetic acid, ethyl ester, urinary excretion accounted for 67.6

- 85.3% of the administered radioactivity. Urinary excretion was unaffected following a single 100 mg/kg bw dose with 61.8

- 78% of the administered radioactivity excreted in urine. Excretion via the feces accounted for the remainder of the administered radioactivity excreted by all treatment groups (12.3

- 35.2%). Excretory patterns did not exhibit gender

- related variability for the low dose groups although a minor difference was o bserved at the high dose. Excretion patterns of the high

- dose group reflected delayed absorption. Because tissue burdens were very low at termination, neither 1

- naphthaleneacetic acid, neither ethyl ester nor its metabolites appear to undergo significan t sequestration. Both urinary and fecal metabolites were quantified by HPLC, TLC and most were identified using HPLC, GC/MS, and HPLC/MS in conjunction with known standards. The major pathway of metabolism involved ester cleavage followed by glycine and glucuronide conjugation at the low and low repeat doses. At the high dose, glucuronide conjugation appeared to play a more important role following ester cleavage. Parent compound was detected at low concentrations (0.5

- 4.7% of administered) only in fece s. Extraction efficiencies appeared to be excellent and most components in the matrices examinedPage 73 of 79

(urine and feces) were adequately quantified and characterized. The available data, based upon studies using labeled 1

- naphthaleneacetic acid, ethyl ester, a ffirmed the metabolism pathway proposed by the investigators.

Metabolism

- Published Studies

There are two published reports dealing with the metabolism of NAA in animals. In one study (Dixon et al , 1977), carboxy

- 14 C

- 1

- naphthylacetic acid (aqueous equ ivalent NaOH solution) at 100 mg/kg was administered intramuscularly to 6 primate species (rhesus monkey: 1M, 1F; cynomolgus monkey: 1F; squirrel monkey: 2F; capuchin: 2F; marmoset: 1M and bushbaby: 1M, 1F), and intraperitoneally to cats (2F, 1M), rat (3F) and fruit bat (1F, 1M), orally to the rabbit (2F) and orally to 2 human males at 5 mg/individual. Urine was collected for 24 hours and analyzed for radioactivity and metabolites, by liquid scintillation counting, chromatography, radiochromatography scan ning, and reverse isotope dilution. In most species tested, 60

- 100% of the administered radioactivity was excreted in the urine by the end of 48 hours. The glucuronic acid conjugate was the major urinary metabolite in man, rhesus monkey, marmoset, rabbit , rat, and fruit bat. In the cat, no glucuronic acid conjugate was detected; taurine and glycine conjugates were the major excretion products. The 1

- Naphthylacetyl glycine conjugate was a major urinary metabolite (>20%) in the cat, squirrel and bushbaby monkey and a minor metabolite in rabbit, rat, capuchia and marmoset monkey. 1

- Naphthylacetylglutamine conjugate was formed only in the cynomolgus, squirrel and capuchin monkeys and marmoset in amounts not exceeding 3% of the administered dose. 1

- Naphthyl acetylturine was excreted by all species except the rabbit, rat and the fruit bat. It was a major excretion product (>6%) in the squirrel and capuchin monkeys, the marmoset and the cat. In addition, when female rats were administered intraperitoneally do ses of 5

- 500 mg/kg, bile duct cannulation showed that 10

- 44% of the radioactivity was present in the bile 3 hours after injection, while 0.6

- 32% was present in the urine. At higher doses, urinary glucuronic acid predominated whereas at the lower doses the glycine conjugates predominated. In the bile, the glucuronic acid conjugate was the major metabolite (>80% of the bile radioactivity), and the glycine conjugate was a minor metabolite (<4% of the bile radioactivity). There was no analysis of the fecal r adioactivity reported.

In another study (Lethco and Brouwer, 1966) carboxy

- 14 C

- 1

- naphthylacetic acid metabolism was investigated in male rats. 14 C

- NAA (neutralized with NaOH) was administered orally by stomach intubation at 0.1, 1.0, 100 and 250 mg/rat (2 rats/dose, weighing 250

- 280 g). Urine and feces were collected for 3 days. For bile cannulation study, 14 C

- NAA was administered orally to 8 and 7 rats (weighing 350

- 435 g) at 0.1 and 100 mg/ rat, respectively, and urine and bile were

collected at 2 a nd 6 hours after administration. Radioactivity was analyzed by liquid scintillation counting, column and paper chromatography and enzymatic analysis. Within 3 days, 71

- 90% of

the administered 14 C was excreted in the urine. At the lower doses (0.1

- 100 mg /kg) most of the radioactivity was excreted during the first 24 hours, while at the higher dose (250 mg/kg), excretion was highest on the second day. Fecal excretion accounted for 3

- 10% at the 0.1

- 1.0 mg/kg doses and 14

- 21% of the administered dose at th e 100 and 259 mg/kg doses. After the third day, no radioactivity was detected in the feces or urine at any dose. Fractionation of the urinary radioactivity by column chromatography and subsequent paper chromatography, UVPage 74 of 79

spectral analysis and B

- glucuroni dase enzyme hydrolysis, revealed that 70

- 93% of the urinary radioactivity was NAA glycine conjugate and NAA glucuronic acid conjugate . The glucuronic acid conjugate predominated at the two high doses and the glycine conjugate predominated at the lower dos e. Minor amounts of unchanged NAA and two other minor unidentified metabolites were also detected in the urine. The fecal radioactivity was not characterized. In the bile cannulation experiment, excretion of radioactivity into the bile and

urine varied by the administered dose. At the low dose of 0.1 mg/kg radioactivity in the urine was nearly four times the radioactivity detected in the bile after 2 hours, while at the higher dose of 100 mg/kg the ratio was reversed. At the high dose a maximum of 29% of the administered radioactivity was recovered at 6 hours, while a maximum of 54% was recovered at the low dose at 2 hours. At the low dose, the NAA glycine conjugate was the major metabolite and the NAA glucuronic conjugate was a minor metabolite, while in the bile the preponderance of these two metabolites was reversed. Also unchanged NAA was detected in the bile but not in the urine at both doses. At the high dose the NAA glucuronic conjugate was the major metabolite in both

urine and bile while the glycine conjugate was a minor metabolite.

A.4.9 Immunotoxicity

870.7800 Immunotoxicity

– Rat

No immunotoxicity studies were available for the risk assessment. The naphthalene acetate toxicity database does not contain evidence of immunotoxicity or any indication the immune
system is a target. As a result t he HED HASPOC waived the requirement for the immunotoxicity study (TXR 0056968).Page 75 of 79

Appendix B. Physical/Chemical Properties

Table 2. Physicochemical Properties of the Naphthalene Acetates

Param eter Value Reference Active Ingredient NAA acetamide
Melting point/range 182

- 184 °C Farm Chemicals Handbook pH of 1% aqueous suspension 5.1 Product CSF Density or specific gravity 0.221 g/cm 3 Product CSF Water solubility (20 °C ) not available

Solve nt solubility (20 °C ) not available Vapor pressure at 20 °C not available Dissociation constant (pK
a ) not available Octanol/water partition coefficient (K
ow ) not available UV/vis absorption spectrum not available
Active ingredient NAA Melting p oint/range 130 °C Farm Chemicals Handbook pH of 1% aqueous suspension 3.45 RD D265117, 5/15/00, B. Kitchens Density or specific gravity 0.45 g/mL CB Nos. 3468 and 3469, 6/3/88, F.

Suhre Water solubility (26 °C ) 0.042 g/100 mL CB Nos. 3468 and 3469, 6/3 /88, F.

Suhre Solvent solubility (26 °C ) xylene 5.5 g/100 mL

CCl 4 1.06 g/100 mL freely soluble in acetone, ether, and chloroform CB Nos. 3468 and 3469, 6/3/88, F.

Suhre

Farm Chemicals Handbook Vapor pressure at 20 °C 0.3 mm Hg at 26 °C CB Nos. 3468 and 3469, 6/3/88, F.

Suhre Dissociation constant (pK
a ) 3.16 x 10

- 4 CB Nos. 3970 and 3971, 7/5/88,

F. Suhre Octanol/water partition coefficient (K
ow ) not applicable; polar compound UV/vis absorption spectrum not available
Active ingredient NAA sodium sal t Melting point/range >300 °C CB Nos. 3468 and 3469, 6/3/88, F.

Suhre pH of 1% aqueous suspension 9.1 CB Nos. 3468 and 3469, 6/3/88, F.

Suhre Density or specific gravity 0.46 g/mL CB Nos. 3468 and 3469, 6/3/88, F.

Suhre Water solubility (26 °C ) 340 g/ 100 mL CB Nos. 3468 and 3469, 6/3/88, F.

Suhre Solvent solubility (26 °C ) insoluble in nonpolar

solvents CB Nos. 3468 and 3469, 6/3/88, F.

Suhre Vapor pressure at 20 °C not available Dissociation constant (pK
a ) 3.16 x 10

- 4 CB Nos. 3970 and 3971, 7/5/88 , F.

Suhre Octanol/water partition coefficient (K
ow ) not applicable; polar compound UV/vis absorption spectrum not availablePage 76 of 79

Table 2. Physicochemical Properties of the Naphthalene Acetates

Param eter Value Reference
Active ingredient NAA ethyl ester Boiling point/range >150 °C Old un

- reviewed Union Carbide data pH of 1% aqueous suspensio n not available Density or specific gravity 1.11 at 20 °C Old un

- reviewed Union Carbide data Water solubility (26 °C ) insoluble Old un

- reviewed Union Carbide data Solvent solubility soluble in xylene, toluene, ethanol, acetone, and methyl ethyl ketone Old un

- reviewed Union Carbide data

Vapor pressure at 20 °C not available Dissociation constant (pK
a ) not available Octanol/water partition coefficient (K
ow ) not available UV/vis absorption spectrum not availablePage 77 of 79

Appendix C

. Occupational Handl er Non

- Cancer Exposure a nd Risk Estimate Equations

Potential daily exposures for occupational handlers were calculated using the following

formulas:

Daily Exposure (mg ae /day) = UE (μg ae / lb ae) * AR (lb ae /A) * AT (A /day) * 1E

- 3 mg/μg

where: Daily Exposure = Amount (mg ae/day) that is available for dermal or inhalation absor ption

UE = Unit Exposure (μg ae / lb ae)

AR = maximum application rate according to pro posed label (lb ae/acre or gal)

AT = daily acres treated (A /day or gal/ day).

The daily doses were calculated using the following formula:

Average Daily Dose (mg ae/kg/day) = [Daily Exposure (mg ae/day) * Absorption (%)] Body Weight (kg)

where: Average Daily Dose = Absorbed dose received from exposure to a pesticide in a given scenario (mg pesticide active ingredient/kg body weight/day)

Daily Exposure = Amount (mg ae/day) that is available for dermal or inhalation absorption

Absorption Factor = A measure of the amount of chemical that crosses a biological

bound ary such as the skin and lungs (%)

Body Weight = Body weight determined to represent the population of interest in a risk assessment (kg).

Margin of Exposure: Non

- cancer risk estimates for each application handler scenario are calculated using a Mar gin of Exposure (MOE), which is a ratio of the toxicological endpoint to the daily dose of concern. The daily dermal and inhalation dose received by occupational

handlers wer e compared to the appropriate PO D (i.e. NOAEL) to assess the risk to occupational handlers for each exposure route. All MOE values were calculated using the following formula:

MOE = Po D (typically a NOAEL in mg/kg/day) ADD (mg/kg/day)

where:Page 78 of 79

MOE = Margin of Exposure: value used by HED to r epresent risk or risk estimates

(unitle ss)

POD = Point of Departure

NOAEL = No Observed Adverse Effect Level (mg/kg/day): Dose level in a toxicity

study, where no observed adverse ef fects occurred in the study

ADD = Average Daily Dose (mg/kg/day): the absorbed dose received from

exp osure to a pesticide in a given scenario.

Combining Exposures/Risk Estimates:

A total aggregated risk index (ARI) was used since the LOCs for dermal exposure (100) and inhalation exposure (1000) are different. The target ARI is 1; therefore, ARIs of les s than 1 are risk estimates of concern. The aggregate risk index (ARI) was calculated as follows.

Aggregate Risk Index (ARI) = 1÷ (1 ÷ RI dermal ) + (1 ÷ RI

inhalation )

Where: Risk Index (RI) = MOE ÷ LOCPage 79 of 79

Appendix D

. Review of Human Research

This ris k assessment relies in part on data from studies in which adult human subjects were intentionally exposed to a pesticide or other chemical. These studies were determined to require a review of their ethical conduct, have received that review and have been determined to be

ethical.

Klonne, D. (1999) Integrated Report for Evaluation of Potential Exposures to Homeowners and Professional Lawn Care Operators Mixing, Loading, and Applying Granular and Liquid Pesticides to Residential Lawns: Lab Project Number: OMA005: OMA001: OMA002. Unpublished study prepared by Riceerca, Inc., and Morse Laboratories. 2213 p. (MRID 44972201).

The PHED Task Force, 1995. The Pesticide Handlers Exposure Database, Version 1.1. Task Force members Health Canada, U.S. Environme ntal Protection Agency, and the National Agricultural Chemicals Association, released February, 1995.