UNITED ST ATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

MEMORANDUM 

Date: December 10, 2015 

OFFICE OF CHEMICAL SAFETY 

AND POLLUTION PREVENTION 

SUBJECT: Dipheoylamine. Human Hea lth Assessment Scoping Document in Support of Registration 

Review. 

PC Codes: 03850 1 

Decision No.: 509355 

Petition No.: NA 

Risk Assessment Type: NA 

TXR No.: NA 

MRIU No.: NA 

DP Barcode: D429256 

Registration No.: RegRev-22 10-1 

Regulatory Action: Registration Review 

Scoping Document 

Case No.: 22 10 

CAS No.: 122-39-4 

40 CFR: 180.1 90 

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Matthew Crowley, Biologist 

Risk Assessment Branch II 

Health Effects Division (7509P) 

Office of Pesticide Programs 

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Pesticide Re-Eva luation Division (7508P) 

Attached is the Health Effects Division's (HED) human health risk assessment scoping document for 

diphenylamine to support registration review. 

Page I of 2 1 
Executive Summary 

The Health Effects Division (HED) has evaluated the database and the most recent human health 

risk assessments for the plant growth regulator diphenylamine. This evaluation was performed 

in order to determine the scope of work necessary to support the established tolerances and 

existing registrations for diphenylamine. The primary sources of information were recent human 

health risk assessments (0339969; T. Goodlow; 13 March 2008 and 0314006; K. Bailey; 8 

August 2005); and the HED chapter of the Reregistration Eligibility Decision (RED) document 

for diphenylamine (T. Myers; I March 1997). HED has evaluated this information for 

diphenylamine in association with updates to toxicity, exposure, and usage databases to 

determine if sufficient data are available and if further updates are needed to support registration 

review. 

Diphenylamine (DPA) is currently registered in the U.S. for post-harvest use on apples and pears 

held in storage to prevent the appearance of skin discoloration known as storage scald, based on 

its antioxidant properties. There are five end-use products, four of which are liquid concentrates 

ranging from 10-31% diphenylamine and one 99% ai solid/powder product. The liquid 

concentrate products are applied to apples and pears via conveyor drenching/flooding, truck 

drenching. or thennofogging at a rate of approximately 0.26 lb ai/ton or 0.02 lb ai/gallon of 

dilute solution. The solid/powder formu lation is applied to apples in warehouse storage via 

them1ofogging at a rate of 0.026 lb ai/ton. 

The toxicology database for diphenylamine is complete. Acute and subchronic neurotoxicity, 

immunotoxicity, and inha lation studies are not available for diphenylamine. However, the 

Hazard and Science Policy Council (HASPOC) determined that the studies are not required for 

diphenylamine, based on a weight of evidence approach, considering the ava ilable hazard and 

exposure information (TXR#0057260). 

The hematological system, liver, spleen, and kidneys are affected after oral exposure to 

diphenylamine. There is no evidence of increased quantitative or qualitative susceptibility of the 

young in developmental and reproduction studies; the FQPA factor has been reduced to IX. 

There is no carcinogenicity or mutagenicity concern after exposure to diphenylamine. However, 

diphenylnitrosamine, an impurity of diphenylamine, is classified as a probable human 

carcinogen, with a calculated cancer potency factor (Q l *)of 4.9 x I 0 (mg/kg/day)" 1

• Therefore, 

cancer risks associated with nitrosan1ine have been considered in previous risk assessments and 

should continue to be considered during registration review fo r dietary, occupational handler and 

postapplication cancer assessments. 

In the previous assessments, endpoints and points of departure (PODs) were selected for chronic 

dietary and occupational sho1t- and intermediate-term dermal and inhalation exposure. No acute 

dietary risk assessment was conducted. Long-term dermal and inhalation risk assessments were 

not conducted since these exposures are not anticipated based on the existing uses. 

HED has not revised the endpoints, doses, and safety factors for the purpose of this scoping 

assessment for registration review. Therefore, future assessments should take into consideration 

Page 2of21 
the appropriateness of the existing endpoints and doses selected for risk assessment, based on 

science policies and risk assessment methodologies in place at the time of registration review. 

The FQPA factor should also be revisited in light of any revised endpoints and points of 

departure. 

The residue chemistry database is adequate lo support registration review requirements. 

Adequate metabolism (crops and li vestock), storage stability, magnitude of the residue, and 

processing data are available to support the registered uses. Adequate methods are available for 

enforcement of the currently established tolerances. The tolerance expression needs to be 

updated to include both coverage and compliance statements. ln addition, there is an existing 

diphenylarnine tolerance for pears, but it is unclear whether a use on pears is still supported by 

the registrant. The dietary exposure database, including the potential for residues in food, is 

adequate to support current registration requirements. Based on the postharvest use pattern, 

drinking water exposure to diphenylamine is not anticipated and has not been included in prior 

assessments. The last risk assessment provided chronic dietary exposure estimates for 

diphenylamine that are not of concern for all population subgroups. Risk estimates for the 

impurity diphenylnitrosamine, were also not of concern. 

There are no proposed or current registrations for products containing diphenylamine that allow 

residentia l use. Therefore, residential handler and post-application exposure assessments will 

not be needed during Registration Review. Unlike aerial or airblast applications to agricultural 

fi eld crops. post-harvest drench treatment is not a use that is typically considered for risk 

assessment of spray drift and volatilization. Incorporation of these assessments during 

Registration Review should be determined in the context of this use pattern. 

Through use of surrogate datasets and the chemical-specific data submitted by the registrants, the 

occupational exposure database is adequate to support registration review of diphenylamine. 

The most recent occupational assessments are not reflective of current policies and data, so these 

assessments should be updated. For assessment of exposure for drench operators, the 

registration review risk assessment should: a) reconsider the 2005 assessment characterization of 

drench operator exposure as negligible; b) review and utili ze the chemica l-specific use and 

exposure information provided in the registrant submissions (MRJDs 4421 250 1 and 4453400 I); 

and c) consider the use of open-cab airblast applicator exposure as a surrogate dataset. For 

exposures to workers who handle the treated commodities (e.g., sorters and packers), the "PostHarvest Standard Operating Procedure (SOP)" (March 2012) and the referenced literature study 

(Gagoulia, et a l, 201 2) should be used. For all occupational exposure assessments, a cancer risk 

assessment for the impurity nitrosamine should be conducted. 

The structure and chemical names, as well as the chemical and physical properties for 

diphenylamine can be found in the tables in Attachment I. 

Page 3 of21 
Hazard ldentificationffoxicology 

The toxicology database for diphenylamine is complete. The Hazard and Science Policy Council 

(HASPOC) based on a weight of evidence approach, considering the available hazard and 

exposure information, concluded that the immunotoxicity, neurotoxicity battery (acute and 

subchronic), and inhalation studies are not required (TXR#0057260). 

The hematological system, liver, spleen, and kidneys are affected after oral exposure to 

diphenylamine. The hematological changes observed included decreases in red blood cell 

(RBC), hemoglobin, and hematocrit. Additionally, increases were seen in Mean Corpuscular 

Volume (MCV), Mean Cell Hematocrit (MCH). platelets, and reticulocytes. Discoloration of the 

spleen and li ver was also observed, along with increased li ver and spleen weights, 

extramedullary hematopoiesis, hemosiderosis (liver), and congestion (spleen). In the kidney, 

discoloration. brown pigment deposits, increased kidney weights, and dark urine were observed. 

Dark red foci in the stomach were seen in both sexes after dem1al exposure. 

No evidence of increased quantitative or qualitative susceptibility of the young to diphenylamine 

was observed in developmental/reproduction studies. The FQPA factor has been reduced to l X 

for diphenylamine based on the following: 1) the toxicology database is adequate to assess preand post-natal toxicity; 2) there was no evidence of increased susceptibility following in 11tero 

exposure to rat and rabbits and pre/post natal exposure to rats; 3) there was no concern for 

potential developmental neurotoxicity, and a developmental neurotoxicity study is not required: 

and 4) there are no residual uncertainties identified in the exposure databases. The dietary (food 

and drinking water) exposure assessment will not underestimate potential exposures for infants 

and children, and non-dietary exposure is not expected based on the use pattern. 

Diphenylamine is classified as '·not likely to be carcinogenic to humans," and there is no 

mutagenicily concern. However, diphenylnitrosamine! an impurity of diphenylamine! is 

classified as a probable human carcinogen, based on bladder tumors in rats and reticulum cell 

sarcomas in mice, as well as a structural relationship to carcinogenic nitrosamines. The cancer 

potency factor for diphenylnitrosamine is 4.9 x I 0 (mg/kg/day)' 1

• Cancer risks associated with 

nitrosamine have been considered in previous risk assessments and should continue to be 

considered during registration review for dietary, occupational handler and postapplication 

cancer assessments. 

In acute lethality studies, diphenylamine has low toxicity (Toxicity Category Ill or IV) via the 

oral and dermal routes. It is slightly irritating to the skin (Category 111) and severely irritating to 

the eye (Category I). For acute inhalation, a data waiver was granted for the technical material 

due to issues with producing a small particle size. Howeve r, low toxicity (Category Ill) was 

observed in an acute inhalation study with the formulation (EC-283; 31.0%). Diphenylamine is 

not a skin sensitizer. 

Metabolism data in the rat indicate that absorption of diphenylamine is rapid and complete 

within 24-hours. Urine was the major route of excretion at both low and high doses, with 

between 68 and 81 % of radioactivity being recovered for both sexes at single or repeated doses. 

No significant tissue residue levels were found post exposure. 

Page 4 of2 1 
Endpoints and points of departure (PO Os) were selected for chronic dietary and occupational 

short- and intermediate-term dermal and inha lation exposure. Long-term dermal and inhalation 

exposure is not anticipated based on the existing uses. No acute dietary risk assessment has been 

conducted for diphenylamine. The need for an acute dietary assessment should be re-evaluated 

duri ng registration review since an appropriate endpoint/POD could possibly be selected from 

the in vivo mouse mi cronucleus study. However, it should be noted that the effects observed in 

the study after acute exposure were seen at the limit dose. For chronic dietary risk assessment, 

the endpoint selected was based on alterations in clinical chemistry and kidney effects at the 

lowest observed adverse effects level of 50 mg/kg/day in a chronic dog study, with a no observed 

adverse effects level of l 0 mg/kg/day. For dermal exposure, a 21 day dermal toxicity study with 

a NOA EL of 500 mg/kg/day was selected, based on stomach effects observed at the LOAEL 

1000 mg/kg/day. For inhalation exposure, a rat developmental study was used with a NOAEL of 

50 mg/kg/day, based on spleen effects observed at the LOAEL of I 00 mg/kg/day. (Attachment 

2). While these endpoints and doses are considered appropriate, during registration review they 

should be reexamined in light of cunent HED guidance, and in the event new data become 

ava il able . 

Conclusions.for Hazard ldent[fication/Toxicology 

The toxicology database for diphenylamine is complete, and no new data are needed. However, 

during registration review the endpoints, points of departure and safety factors used for risk 

assessment purposes should be reexamined based on current HED policy, as well as any new 

data received. Furthermore, the need for an acute dietary assessment should be re-evaluated 

during registration review since an appropriate endpoint/POD could be selected from the in vivo 

mouse micronucleus study. 

Dietary Exposure 

Tolerances for diphenylamine are listed in 40CFR§180. 190 and range from 0.0 I to 30 ppm. 

The residue chemistry database is adequate to support registration review. Adequate metabolism 

(crops and livestock), storage stability, magnitude of the residue, and processing data are 

available to support the registered uses. Adequate methods are available for enforcement of the 

currentl y established tolerances. No residue chemistry data deficiencies were c ited in the 

previous risk assessment. HED has previously determined that the residue of concern in plants 

and livestock commoditi es for both tolerance enforcement and risk assessment purposes is parent 

diphenylamine. 

No acute endpoint wa5 previously identified in earlier risk assessments; therefore, no acute 

dietary exposure assessment was performed. The chronic dietary exposure estimates in the 

previous risk assessment assume I 00% percent crop treated and tolerance-level residues for all 

registered commodities (03 19225, D. Dotson, 8/8/2005). Based on the post-harvest use pattern 

associated with diphenylamine, drinking water exposure is not anticipated and no drinking water 

estimates have been provided, nor have any been included in previous risk assessments. The 

chroni c dietary risk estimates were not of concern for the general U.S. population and all 

population subgroups. All subgroups use less than or equal to 90% of the chroni c population 

Page 5 of2 I 
adjusted dose (cPAD). A dietary risk assessment was also conducted for diphenylnitrosamine, to 

determine the cancer risk from exposure to the impurity; the risk estimates were not of concern. 

Since the last dietary assessment, I-JED updated its dietary mode l to incorporate more recent 

consumption data from the National Health and Nutrition Examination Survey (NHANES). A 

new dietary assessment may be needed if one or more of the following occur: new data are 

identified which impact dietary exposure estimates; new toxicological points of departure are 

identified, including revisions to the FQPA SF; OPP dietary exposure policies and procedures 

are revised. 

Conclusions for DielaJJ' Exposure 

The dietary exposure database is adequate to support the existing registrations and tolerances. 

No new residue chemistry data are required. A new dietary assessment may be needed if one or 

more of the following occur: new data are identified which impact dietary exposure estimates; 

new toxicological points of departure are identified, including revisions to the FQPA SF or the 

identification of an acute dietary endpoi nt; OPP dietary exposure poli cies and procedures are 

revised. Drinking water residues were not previously included in the dietary exposure 

assessment based on the postharvest use pattern. It is not anticipated that this drinking water 

residue situation will change during registration review. 1-IED recently updated its dietary model 

to incorporate more recent consumption data from the National Health and Nutrition 

Examination Survey (NHANES). This new version of the model will be used du ring registration 

review if a new dietary assessment is needed. 

Residential Exposure 

There are no proposed or current registrations for products containing diphenylamine that allow 

residential use. Therefore, residential handler and post-appli cation exposure assessments will 

not be needed during Registration Review. Unlike aerial or airblast applications to agricultural 

field crops, post-harvest drench treatment is not a use that is typically considered for risk 

assessment of spray drift and volatilization. lncorporation of these assessments during 

Registration Review should be determined in the context of this use pattern. 

Aggrega te Risk Assessment 

In accordance with the FQPA, HED must consider and aggregate (add) pesticide exposures and 

risks from three major sources: food, drinking water, and residential exposures. In an aggregate 

assessment, exposures from relevant sources are added together and compared to quantitative 

estimates of 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. As diphenylamine has no residential uses, and no exposure is expected for 

drinking water sources, aggregate exposure and risk is equivalent to the dietary (food) exposure 

and risk. Risk estimates for the US population and all population subgroups are below HED's 

level of concern. 

Occupational Exposure 

Page6of21 
Diphenylamine is registered for post-harvest use on apples and pears. There are fi ve end-use 

products, four of which are liquid concentrates ranging from 10-31 % diphenylamine and one 

99% ai solid/powder product. The liquid concentrate products are applied to appl es and pears 

via conveyor drenching/flooding, truck drenching, or thermo fogging at a rate of approximate ly 

0.26 lb ai/ton or 0.02 lb ai/gallon of dilute solution. The solid/ powder formulation is applied to 

apples in warehouse storage via thermo fogging at a rate of 0.026 lb ai/ton. Each use is described 

in more detail below. 

• Truck drenching: Similar to an automated car washing process, a truck loaded wlth 20-

96 bins, each containing approximately 900 lbs of apples or pears, drives into the 

drenching area, such that the truck cab is beyond/outside the treatment area. The driver 

stays in the cab while the operator turns on the high-flow flood nozzles and then slowly 

drives through as the apples or pears are drenched. The nozzles are turned off until the 

next truck pulls up. 

• Conveyor drenching/flooding: Direct spray of the apple or pear bins in a stationary 

position or as they move past the spray nozzles on a chain or track driven conveyor belt. 

• Thermofogging: Apple bins are placed in a storage room/chan1ber (from 500 to 6,000 

bins per room). The room is closed and a rigid pipe and nozzle extending from a 

them1ofogging machine enters the storage room through an access hatch or porthole. 

Diphenylamine is loaded into the maclline, flash heated, and a fog is applied through the 

machine into the enclosed room. Twelve hours prior to and during treatment, room 

cooling systems. and humidifiers are turned off. Circulation fans are turned off 

immediately prior to and during treatment. Once the fogger is operational, an individual 

monitors the machine to ensure it is functi oning properly. The fogging process takes 

about 1 hour to treat 125 tons of fruit. 

Based on the registered use patterns, short-/interrnediate-term dermal and inhalation exposures 

during the application process (i.e., mixing/loading, applying) are anticipated. ln addition, there 

is also potential short-/intermediate-term post-application exposure for people handling treated 

apples and pears. Long-term occupational exposures are not anticipated. 

Occupalional Handlers 

After the diphenylarnine reregislration eligibi lity decision (RED) in 1998, which assessed 

occupational handler exposures for post-harvest truck drenching treatment of apples only, an 

occupational handler exposure assessment was conducted in 2005 to address FIFRA Section 3 

new use registrations for thennofogging and the addition of use on pears. In both assessments 

short-/intermediate-term dermal and inhalation handl er non-cancer risks were quantified and no 

risks of concern were identified. Although a cancer risk assessment has not been previously 

conducted for diphenylamine due to its classification as '·not likely to be carcinogenic" to 

humans, an occupational handler cancer risk assessment for the impurity diphenyl nitrosamine 

was conducted in the 1998 RED. No cancer risk estimates of concern were identified. 

All assessments considered the label-required work attire and personal protective equipment 

(PPE) of long pants, long sleeve shirt, shoes/socks, and chemical-resistant gloves. Full-face 

respirators are required for certain activities related to the thermofogging operation. 

Page 7of 2 1 
The previous risk assessments do not reflect the most up-to-date exposure data or inputs for 

occupational handler scenarios. During Registration Review, updated non-cancer and cancer 

occupational handler dermal and inha lation risk assessments should be conducted to reflect 

c urrent policies and data sets. The following scenarios should be assessed: 

• Mixing/loading liquid concentrates for conveyor drenching/fl ooding, truck drenching, 

and therrnofogging. 

• Mixing/loading solid/powders for thermofogging application. 

• Operator/Applicator exposure during truck drenching and/or conveyor drenching 

(although not directly involved in the application process, workers can experience dennal 

and inhalation exposures as bystanders). 

Assessment of the mixing/loading scenarios should be fairl y straightforward and done using the 

most current surrogate datasets. However, drench operator exposure is a scenario for which 

there is no current standard methodology. [n the 1998 RED, since no exposure data were 

available, thjs scenario was assessed using exposure data for aerial " flaggers" as a surrogate 

dataset. The 1998 RED assessment also included application information from the registrant risk 

assessment submission "Estimation of Dermal and Inhalation Exposure at Apple Drenching Sites 

for Diphenylamine" (MRlD 442 1250 I). While that registrant submission also utilized surrogate 

data to assess drench operator risks, it is the scenario-specific use information that should be 

reviewed during registration review for assessment of the drench operator scenario. Similarl y, 

use information provided by the " DPA Task Force" during a meeting with EPA on August 3, 

20 15 (FOCUS Meeting) may also be useful. Another registrant submission, perhaps more 

directly related to drench operator exposure, "Monitoring of Deposition of Diphenylamine 

Residues Associated with Postharvest Apple Treatment" (MRlD 4453400l), through use of 

patches attached to stationary stands, might provide additional characterization of the exposure 

potential during drench operation. This submission has not been reviewed by HED, but does 

appear to have detected residues that could be used to represent drench operator exposure. It 

should be reviewed and considered during registration review. The registration review 

assessment may also consider exposure data from open-cab airblast applications as a reasonable, 

if not conservative, surrogate dataset to represent the drench operator scenario. Finally, the 2005 

assessment did not include a drench operator exposure scenario as the truck driver was assumed 

to vacate the truck cab and operation of the drenching done remotely. This characterization 

should also be considered in the context of the q uanti tati ve 1998 RED assessment and related 

registrant data submissions regarding drench operator exposure. 

The Registration Review process should also be sure to reconc ile bandier work attire and PPE 

with corresponding diphenylamine end-use acute toxicity-based requirements and potentia l 

requirements based on the registration review occupational handler risk assessment. 

Occupational Post-application Exposure 

In comparison to standard foliar application of agricultural crops, where workers experience 

post-application exposure while performing hand labor tasks in the field, exposure following 

diphenylamine post-harvest treatments may occur as a result of handling treated apples, perhaps 

Page 8 of21 
during the packing process. The 1998 RED did not include a quantitative post-application 

exposure assessment, stating that " handling of appl es and apple bins are done by forklift 

machinery thereby minimiz ing, if not eliminating, possible worker exposure ." However, in 

2005, a quantitative short-/intennediate-term post-application dennal exposure assessment was 

conducted based on transfer coefficients for tree crop harvesting, assuming that workers could 

experience exposure via direct handling of treated post-harvest apples and pears. No dermal 

risks of concern were identified. 

Neither the 1998 RED nor the 2005 assessment quantitatively addressed post-application 

inhalation exposure, citing both diphenylamine's vapor pressure and the likelihood of airborne 

aerosols to settle out by the time workers would contact treated fruit. For thermofogging in 

particul ar, as described in the 2005 assessment, in which a) no personne l are inside the storage 

rooms during application, b) there is typicall y a multi-day period before which workers would 

handle the treated fruit, and c) the requirement for a full-face respirator during treatment or 

depending on the extent of acti ve ventilation, 9 to 24 hours following application, postapplication inhalation exposure is unlikely. 

Since these assessments were completed, HED has developed a methodology that more 

accurately represents handling post-harvest treated commoditi es. Based on a study monitoring 

dermal and inhalation fo r workers handling (i.e., sorting, culling, and packing) post-harvest 

treated pears and citrus fruit, the .. Post-Harvest Commodity Treatment" Standard Operating 

Procedure (March 20 12) should be utilized to assess post-application exposures to post-harvest 

diphenylamine-treated apples and pears. As the basis for the methodology is a study that 

monitored workers handling the commodities immediately after they were treated, it might not be 

an exact match for handling diphenylamine-treated commoditi es, particularly with respect to 

inhalation exposure. A published literature study, "Determination of diphenylamine in 

contaminated a ir of agri cultural buildings using active sampling on solid sorbents" (Gagoulia, et 

al., 20 12, Intl J Env Anal Chem, Vol 92, Issue 13), may provide better characterization of postapplication inhalation exposure than use of the Post-Harvest SOP. 

There fore, during Registration Review the Post-Harvest SOP and the referenced li terature study 

should be considered to assess non-cancer and cancer risks for post-application exposures. 

Specificall y the assessment should add ress dermal and inhalation exposures following truck and 

conveyor-type drenching and only dermal exposures following thermofogging treatments. 

Inhalation exposures following thermofogging treatments are unlike ly, for the reasons outlined in 

the 2005 assessment. To use the SOP, the exposure assessor will need application rate 

information in terms of a)% diphenylamine in the treatment solution, b) lbs diphenylamine per 

lb commodity, and c) lb diphenylamine per gallon of treatment solution, all of which can be 

detem1ined from the product labels. 

The Registration Review process should also be sure to reconcile whether restricted entry 

intervals (REls) based on acti ve ingredient acute toxicity-based requirements are applicable for 

diphenylamine. 

Conclusions.for Occupational Exposure Assessment 

Page 9 of 2 1 
Through use of surrogate datasets and the chemi cal-specific data submitted by the registrants. the 

occupational exposure database is adequate to support registration review of diphenylamine. 

The most recent occupational assessments are not re nective of current poli cies and data, so these 

assessments should be updated. For assessment of exposure for drench operators, the 

registration review risk assessment should: a) reconsider the 2005 assessment characterization of 

drench operator exposure as negligible; b) review and consider the chemical-specific information 

provided in the registrant submissions described above (MRIDs 442 1250 I and 4453400 1 ), and 

c) consider the use of open-cab airblast applicator exposure as surrogate dataset. For exposures 

to workers who handle the treated commodities (e.g., sorters and packers) the "Post-Harvest 

sop·• (March 2012) and the referenced literature study should be used. For all occupational 

exposure assessments a cancer risk assessment for the impurity nitrosamine should be conducted. 

Public Health and Pesticide Epidemiology Data 

For the evaluation of pesticide incident data for diphenylamine, both the OPP Incident Data 

System (IDS) and the Centers for Disease Control and Prevention/National Institute for 

Occupational Safety and Health (CDC/NIOSH) Sentinel Event Notification System for 

Occupational Risk-Pesticides (SENSOR) databases were consulted. The purpose of the database 

search was to identify potential patterns in the frequency and severity of the health effects 

attributed to diphenylamine exposure. Diphenylamine is not included in the AHS, and therefore 

the study does not provide usefu l information. There were no incidents involving diphenylaminc 

reported to either Main or Aggregate IDS, from January 1, 2010 to May 27, 2015. A review of 

SENSOR-Pesticides 1998-2011 identifies no incidents involving diphenylamine. 

There are no incident cases reponed for diphenylamine in IDS and SENSOR-Pesticides. 

Therefore, there does not appear to be a concern at this time that would warrant further 

investigation. The Agency will continue to monitor the incident infom1ation and if a concern is 

triggered, additional analysis will be included in the risk assessment. 

Tolera nce Assessment a nd International Harmonization 

As stated above, for diphenylamine are listed in 40CFR§180.190 and range from 0.0 I to 30 

ppm. HED has previously determined that the residue of concern in plants and livestock 

commodities for both tolerance enforcement and risk assessment purposes is parent 

diphenylarnine. Acceptable analytical methods are available to enforce tolerances for residues of 

diphenylamine in plant and livestock commodities. 

According to HED's Interim Guidance on Tolerance Expressions (S. Knizner; 27 May 2009), 

the tolerance expression for diphenylamine cited in 40 CFR § 180.190 should be revised to state: 

Tolerances are established for residues of diphenylamine, inc luding its 

metabolites and degradates, in or on the commodities listed in the table below. 

Compli ance with the tolerance leve ls specified below is to be determi ned by 

measuring only diphenylamine, in or on the commodity. 

Page 10 of21 
f n addition, during the registration review risk assessment, HED will review the language 

for the existing tolerances and make recommendations to update the tolerances to be 

consistent with current practices. SpecificalJy, HED will recommend that the following 

be removed in the 40 CFR § 180.190: All references to preharvest and postharvest use, 

and impregnated wraps need to be removed from the apple and pear tolerance commodity 

listings. The preharvest and impregnated wraps references are in the apple tolerance 

commodity listing. and the postharvest use reference is in both the apple and pear 

tolerance commodity listings. It is noted that only postharvest uses of diphenylamine are 

cun-ently registered. with the preharvest and impregnated wraps references being based 

on uses that have been canceled (USEPA, Final RED, April 1998). Similarly, all 

references to preharvest uses and impregnated wrap uses need to be removed from the 

currently registered labels. 

The residue definition for both Codex and Canada is parent diphenylamine, and is therefore 

identical to that of the U.S. The international residue limit status sheet can be found in 

Attachment 4. Codex MR Ls have been established fo r the postharvest use of diphenylamine on 

both apples and pears. The apple MRL is 10 ppm and the pear MRL is 5 ppm, which is identical 

to the established U.S. tolerances. Canada has an apple MRL of 5 ppm for postharvest treatment. 

The residue data used to establish the U.S. tolerance are based on the current U.S. use pattern, 

and indicate that the I 0 ppm tolerance is appropriate. As a result, the U.S. will continue to 

harmonize with Codex at I 0 ppm, and will not reduce the cun-ent tolerance to the Canadian MRL 

of 5 ppm. 

Environmental Justice 

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

human health risk assessment, in accordance with U.S. Executive Order 12898, ·'Federal Actions 

to Address Environmental Justice in Minority Populations and Low-Income Populations," 

http://www.eh.doc. 1wv/nepa/tools/guidance/Yolume 1 /2-6-EO 12898envj ustice.pdf). 

As a part of every pesticide risk assessment, OPP considers a large variety of consumer 

subgroups according to well-established procedures. In line with OPP policy, HED estimates 

risks to population 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 compiled 

by the USDA under the Continuing Survey of Food f ntakes by Individuals (CS FIT) and 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 circumstances warrant. 

The Office of Pesti cide Programs (OPP) typically considers the highest potential exposures from 

the legal use of a pesticide when conducting human health risk assessments, including, but not 

limited to, people who obtain drinking water from sources near agricultural areas, the variability 

of diets within the U.S., and people who might be exposed when harvesting crops. Should these 

Page 11 of2 1 
highest exposures indicate potential risks of concern, OPP further re fines the risk assessments to 

ensure that the risk estimates are based on the best available informat ion. 

Endocrine Disruptor Screening Program 

As required by FIFRA and FFDCA, EPA reviews numerous studies to assess potentia l adverse 

outcomes from exposure to chemicals. Collecti vely, these studies include acute, subchronic and 

chronic toxicity, including assessments of carcinogenicity, neurotoxicity, developmental, 

reproductive, and general or systemic toxicity. These studies include endpoints which may be 

susceptible to endocrine influence, including effects on endocrine target organ histopathology, 

organ weights, estrus cyclicity, sexual maturation, fertility, pregnancy rates, reproductive loss, 

and sex ratios in offspring. For ecological hazard assessments, EPA evaluates acute tests and 

chronic studies that assess growth, developmental and reproductive effects in different 

taxonomic groups. As part of its most recent registration decision for diphenylamine, EPA 

reviewed these data and selected the most sensitive endpoints for relevant risk assessment 

scenarios from the existing hazard database. However, as required by FFDCA section 408(p), 

diphenylamine is subject to the endocrine screening part of the Endocrine Disruptor Screeni ng 

Program (EDSP). 

EPA has developed the EDSP to detern1ine whether certain substances (including pesticide 

acti ve and other ingredients) may have an effect in humans or wildlife similar to an effect 

produced by a "naturally occurring estrogen, or other such endocrine effects as the Administrator 

may designate." The EDSP employs a two-tiered approach to making the statutoril y required 

determinations. Tier 1 consists of a battery of I I screening assays to identify the potential of a 

chemical substance to interact with the estrogen, and rogen, or thyroid (E, A, or T) hormona l 

systems. Chemi cals that go through Tier 1 screening and are found to have the potential to 

interact with E, A. or T hormonal systems will proceed to the next stage of the EDSP where EPA 

will determine which, if any, of the Tier 2 tests are necessary based on the available data. Tier 2 

testing is designed to identify any adverse endocrine-related effects caused by the substance, and 

establish a dose-response relationship between the dose and the E, A, or T effect. 

Under FFDCA section 408(p), the Agency must screen all pesticide chemi cals. Between 

October 2009 and February 2010, EPA issued test orders/data call-ins for the first group of 67 

chemicals, which contains 58 pesticide active ingredients and 9 inert ingredients. A second list 

of chemicals identified for EDSP screening was published on June 14, 2013fl I and includes some 

pesticides scheduled for registration review and chemicals found in water. Neither of these lists 

should be construed as a list of known or likely endocrine disruptors. 

For further infonnation on the status of the EDSP, the policies and procedures, the lists of 

chemicals, future lists, the test guidelines and the Tier I screening battery, please visit our 

website. 

Cumulative Risk Assessments 

Ill Sec http://www.rcgulations.gov/#!documentDctail;D=EPA-HQ-OPPT-2009-0.t77-007.t for the final second 

list of chemicals. 

Page 12 o f 2 1 
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 diphenylamine and any other substances, and diphenylamine does not appear to produce a 

toxic metabolite produced by other substances. For the purposes of this action, therefore, EPA 

has not assumed that diphenylamine 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 evaluate the cumulative effects of such chemicals, see the policy 

statements released by EPA' s Office of Pesticide Programs concerning common mechanjsm 

determinations and procedures for cumulating effects from substances found to have a common 

mechanism on EPA 's website at http://www2.epa.gov/pesticide-science-and-asscssing-pesticiderisks/cumulntive-assessment-risk-pesticides 

Human Studies 

The previous diphenylamine risk assessments relied in part on data from studies in which adult 

human subjects were intentionally exposed to a pesticide or other chemical. Studies such as the 

Pesticide Handlers Exposure Database, Outdoor Residential Exposure Task Force, and the 

Agricultura l Handler Exposure Task Force have been reviewed by the Agency and found, on the 

basis of available evidence, to have been neither fundamentall y unethical nor significantly 

deficient relati ve to standards of ethical research conduct prevailing when they were conducted. 

There is no barrier in EPA 's "Protection of Human Subjects" Regulation to reliance on these 

studies. If used for the purposes of registration review, nvo data sources noted in this scoping 

document (MRfD 4453400 I and Gagoulia, et al) should be reviewed for compliance with human 

studies regulations. The other referenced submission (MRlD 44212501) was a registrantauthored risk assessment and was not comprised of any research involving humans .. 

Data Requirements 

There are no outstanding toxicology, residue chemistry, or exposure data requirements. 

References 

Author Barcode Date Title 

S. Recore 0429308 6/23/2015 Diphenylamine: Tier l (Scoping) Review of Human Lncidents and 

Epidemiology 

T. Goodlow 0339969 3/ 13/2008 Diphenylamine: Proposed Section 3 Registration of a New 

Formulation for Use on Apples. 

K. Bailey 0314006 6/8/2005 Human I lea Ith Risk Assessment for the Proposed Section 3 Use of 

Diphenylamine on Pear and for the Registration of a New Product 

and Method for the Aoolication of Diphenylamine to Aooles. 

T. Meyers NIA 3/1/1997 The HED Chapter of the Reregistration Eligibility Decision 

Document (RED) for Diphenylamine 

Attachments 

Attachment 1. Diphenylamine Chemical Properties 

Attachment 2. Diphenylamine Endpoint Selection Tables 

Attachment 3. Diphenylamine Toxicity Profile Tables 

Attachment 4. International Residue Limit Status 

Page 13 of21 
Attachment I. Oiphenylaminc Chemical Properties 

Table I.A. Oiphenylamine Chemica l ldentity Table 

Compound H 

D Common name Diphenylamine 

Company experimental DPA 

names 

lUPAC name Diphenylamine 

CAS name Diphenylamine 

CAS # 122-39-4 

End-use products/EP DPA super refined; Decco No Scald; DPA Aerosal; Shield DPA 15%; No Scald 

DPA EC-283; EFOG-100; EGOG-1 70 

Table 1.8. Physicochemica l Properties of the Technical Grade Test Compound. 

Parameter Value Reference 

Melting point/range 52.7-54.7 °C 42716501 

pH 5.9 42716501 

Density absolute density = I. 18 g/crn3 at 25 °C 427 1650 1 

Water solubility (25°C) 0.038-0.042 mg/ml.. 

Solvent solubility (at 25°C) acc1oni1rile at 808-897 mg/ml, 42898801 

methanol at 454-492 mg/mL. octanol at 

204-237 mg/ml, and hexane at 53-66 

mg/ml 

Vapor pressure Pascal torr 42876201 

25 °C 8.52 x 10·

2 6.39 x 104 

35 °C 3.09 x 10·

1 2.32 x 10·3 

45 °C 9.46 x 10·

1 7.09 x 10·3 

Dissociation constant, pK. pKa = 1.03 at 20°C in 4. 75% Et OH 42716401 

Octanol/water pa1tition coefficient, 3.6 4282660 1 

Log(Kow) 

UV /visible absorption spectrum not available 

Page 14 of21 
Attachment 2. Diphcnylamine Endpoint Tables. 

Table 2.A. Toxicological Doses and Endpoints for Diphenylamine for Use in Dieta ry Huma n Health Risk 

Assessments. 

RID, PAD, 

Exposure/ Point of Uncertainty/FQ Level of 

PA Safety Concern for Study and Toxicological Effects Scenario Departure Factors Risk 

Assessment 

Acute Dietary An appropriate endpoint attributable to a single dose was not identified. 

(A II populations 

Chron ic Dietary NOAEL= 10 UF" = I Ox Chronic Rm= Chronic Toxicity- dog 

(All Populations) mg/kg/day UF11 = I Ox 0. 1 mg/kg/day LOAEL (mg/kg/day): 50 

FQPA SF= Ix cPAD =O.I based on alterations in clinical chemistry 

mg/kg/day parameters (increased BUN, cholesterol, 

total bilirubin) and increased 

absolute/relative kidney weights. 

Dermal NOAEL=500 UF" = I Ox Residential LOC 2 1 Day Dermal-Rabbit 

Short-Term mg/kg/day UF11 = IOx for LOA EL: (mg/kg/day) I 000 

(I - 30 days) and FQPASF= Ix MOE = 100 based on effects in the stomach {dark red 

Intermed iate- foc i in both sexes) 

Tenn (I - 6 

Months) 

Inhalation NOAEL =50 UF" = I Ox Residential LOC Developmental Toxicity-Rat 

Short-Term mg/kg/day UF11 = I Ox for LOAEL= IOO mg/kg/day 

(I - 30 days) and FQPA SF= Ix MOE = 100 based on increased spleen weights and 

Intermediate- discoloration of the spleen 

Tenn (I - 6 

Months) 

Cancer (oral, Classification: Diphenylamine is classified as "Not likely to be Carcinogenic to Humans." 

dermal. Diphenylnitrosamine (impurity) is classified as a probable human carcinogen, 

inhalation) QI*= 4.9 x 10 mg/kg/day. 

Pomt of Departure (POD) = 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. NOA EL= no observed adverse effect level. LOAEL = lowest observed adverse effect level. UF = 

uncertainty factor. UF,, = extrapolation from animal to human (interspecies). UF11 = potential variation in 

sensitiviry among members of the human population (intraspecies). UFL = use of a LOAEL to extrapolate a NOA EL 

FQPA SF = FQPA Safety Factor. PAD = population adjusted dose (c =chronic). Rm = reference dose. MOE = 

margin of exposure. LOC = level of concern. N/ A = not applicable. 

Page 15 of2 1 
Table 2.B. Toxicological Doses and Endpoints for Diphenylamine for Use in Occupational Human Health Risk 

Assessments. 

RfD, PAD, 

Exposure/ Point of Uncertainty/FQP Level of 

Concern for Study and Toxicologica l Effects Scena rio Departure A Safety Factors Risk 

Assessment 

Dermal NOAEL=500 UFA = I Ox Occupational 21 Day Dermal-Rabbit 

Short-Term mg/kg/day UFM = I Ox LOC for LOAEL: (mg/kg/day) 1000 

(I - 30 days) MOE = 100 based on effects in the stomach (dark red 

and foc i in both sexes) 

IntermediateTerm(l -6 

Months) 

Inhalation NOAEL =50 UFA= !Ox Occupational Developmental Toxicity-Rat 

Short-Tem1 mg/kg/day UF11 = !Ox LOC for LOAEL= IOO mg/kg/day 

(I - 30 days) MOE = 100 based on increased spleen weights and 

and discoloration of the spleen 

IntermediateTerm( l -6 

Months) 

Cancer (oral, Classification: Diphenylamine is classified as "Not likely to be Carcinogenic to Humans." 

demial. Diphenylnitrosaminc (impurity) is classified as a probable human carcinogen, 

inhalation) QI*= 4.9 x I 0 (mJ.?/kg/day)"1• 

Point of Departure (POD)= 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. NOA EL = no observed adverse effect level. LOA EL = lowest observed adverse effect level. UF = 

uncertainty factor. UFA= extrapolation from animal to human (interspecies). UF11 = potential variation in 

sensitivity among members of the human population (intraspecies). MOE = margin of exposure. LOC = level of 

concern. NIA = not applicable. 

Atlachment 3. Diphenylamine Tox icity Profile Tables. 

Table 3.A. Acute Toxicity Profile - Diphenylamine Technical 

Guideline No. Study Type MRlD(s) Results Toxicity 

Calel!orv 

870.I 100 Acute oral-rat 00148523 LD~o=2720mg (2490-2980) mQ/kQ. Ill 

870. 1200 Acute dermal-rabbit 00 148524 LDso > 2000 mg/kg II I 

870. 1300 Acute inhalation-rat 43794201 LC50 = 1.46 mg/L 111 

870.2400 Acute eye irritation-rabbit 00148525 Slight eye irritation Ill 

870.2400 *Acute eye irritation-rabbit 41899404 Corrosive: Corneal Opacity I 

870.2500 Acute dermal irritation -rabbit 00 148526 Slight skin irritation Ill 

870.2600 Skin sensitization-guinea pig 43540801 Not a dem1al sensitizer NIA 

• As required by the Pesticide Assessment Guidelines (Subdivision F. 81-4) the eye irritation study failed to include 

an observation period (2 I days) which was sufficient to evaluate fully the reversibility or irreversibility of the effects 

observed. The observation period in the study only lasted 7 days. 

Page 16of21 
Table 3.B Subchronic, Chronic a nd Other Toxicity Profil e-Diphenylamioe Technical 

GDLN Study Type Dose Levels MRID Results 

870.3 100 1992- 13 WEEK ppm = 0, 150, 1500, 7 500, 4233970 1 NOAEL (mg/kg/day): 75 

LOA EL (mg/kg/day): 375 

FEEDING-RAT 15000 based on decreased body 

mg/kg/day= weight and body weight 

gain, dark urine, increased 

0, 7.5, 75, 375, 750 absolute spleen and liver 

weights, congestion in 

Acceptable/Guideline spleen, kidney, and liver, 

discoloration and alterations 

in hernarological and clinical 

chemistry parameters. 

870.J 100 1992- 13 WEEK ppm = 0, I 0, 525, 2625, 5250 4254280 1 NOA EL (mg/kg/day): 2 

FEEDING-MOUSE LOAEL (mg/kg/day): 

mg/kg/day = M/F: 941107, based on 

M:O, 2, 94, 444, 926 liver/spleen alterations 

F: 0, 2, 107, 556, 110 1 (extramedullary 

hematopoiesis in the li ver, 

discoloration and 

Acceptable/Guideline hemosiderosis of the liver, 

congest ion and 

extramedul lary 

hematopoiesis in the spleen). 

870.3 150 1992- 13 WEEK ppm = no1 given 4233980 1 NOA EL (mg/kg/day): 50 

FEEDING-DOG LOAEL (mg/kg/day): not 

mg/kg/day = determined 

0, 5,25, 50 

Acccptable/Nonguideline 

870.3200 1992-2 1 DAY mg/kg/day = 4230490 1 Systemic: NOAEL 

DERMAL-RABBITS 0, I 00, 500, 1000 (mg/kg/day):500 

LOA EL: (mg/kg/day): I 000 

Acceptable/Nonguideline based on effects in the 

stomach (dark foci-red foci 

in both sexes-6/ I 0) 

Dermal: NOAEL 

(mg/kg/day): I 000 

LOA EL (mg/kg/day): 

not determined 

870.3700 1992- mg/kg/day = 4229200 1 Maternal: NOAEL 

DEVELOPMENTAL 0, 10, 50, 100 (mg/kg/day): 50 

TOX-RAT LOA EL (mg/kg/day): I 00 

Acceptable/Guideline based on increased spleen 

weights and discoloration of 

the spleen. 

Developmental: NOAEL 

(mg/kg/day): I 00 

LOA EL (mg/kg/day): not 

Page 17 of2 1 
Table 3.B Subchronic, Chronic and Other Toxicity Profile-Diphenylamine Technical 

COLN Study Type Dose Levels MRID Results 

determined 

870.3700 1983- mg/kg/day = 00 148521 Maternal: NOAEL 

DEVELOPMENTAL 0.33, 100,300 (mg/kg/day): I 00 

TOX-RABBIT LOAEL (mg/kg/day): JOO 

based on decreased body 

weight gains and food 

Acceptable/Nongu id el ine consumption. 

Developmental: NOAEL 

(mg/kg/day): 300 

LOA EL (mg/kg/day): not 

determined 

870.3800 1993-2-GENERA TION ppm= 0, 500, 1500, 5000 42638101 Parental: 

REPRODUCTION-RAT NOA EL (mg/kg/day): not 

mg/kg/day = determined 

M: 0, 40, 115, 399 LOA EL (mg/kg/day): 

F: 0, 46, 131. 448 M/F: 40146, based on gross 

pathological findings in the 

spleen and microscopic 

findings in the kidney, liver, 

Acceptable/Guideline and spleen. 

Reproductive: 

NOA EL (mg/kg/day): 

M/F: I I 5113 I 

LOA EL (mg/kg/day): 

M/F: 399/448 

decreased litter size in both 

generations 

Offspring: 

NOA EL (mg/kg/day): 

M/F: 40/46 

LOAEL (mg/kglday): 

M/F: I 15/ 13 I 

based on decreased body 

weight of F2 pups in late 

lactation 

870.4100 1993- 1 YEAR ppm = not given 43000601 NOA EL (mg/kg/day): I 0 

FEEDING-DOGS LOA EL (mg/kg/day): 50 

mg/kg/day "' based on alterations in 

0, 10, 50. 100 clinical chemistry parameters 

(increased BUN, cholesterol. 

Acceptable/Guideline total bilirubin) and increased 

absolute/re lative kidney. 

liver and spleen weights. 

870.4200 1994- 18 MONTH ppm = O. 525, 2625, 5250 4336950 1 NOAEL (mg/kg/day): not 

CARCINOGENICITY- dctem1ined 

MICE mg/kg/day = LOAEL (mg/kg/day): 

Page 18 of2 1 
Table 3.B Subchronic, Chronic a nd Other Toxicity Profile-Diphenylamine Technical 

GDLN Study Type Dose Levels MRID Results 

M: 0, 73, 368, 756 M/F: 73/91 

F: 0, 91, 455, 937 based on histopathological 

lesions in the spleen 

No evidence of 

carcinogenicity 

Acceptable/Guideline 

870.4300 1994-2 YEAR ppm = 0, 200, 750, 3750, 43401401 NOAEL (mg/kg/day): 

TOXICITY/ 7500 M/F: 29/25 

CARCINOGENICITY- LOA EL (mg/kg/day): 

RAT mg/kg/day = M/F: 147/ 138 

M: 0, 8, 29, 147, 302 based on reduced body 

weight and body weight 

gains, changes in 

hematological parameters, 

ppm = 0, 150, 500, 2500, spleen and kidney lesions 

5000 and increased clinical signs 

of toxicity. 

mg/kg/day = 

F: 8, 25, 138, 286 No evidence of 

carcinogenicity 

Acceptable/Guideline 

870.5 100 1992-BACTERIAL 6.7, 10.0, 33.3, 66.7, and 100 42312101 Negative 

REVERSE MUTATION μg/plate (Salmonella 

typhimurium) in the absence 

of metabolic activation (S9); 

10.0, 33.3, 66.7, I 00, and 

333 mg/plate in the presence 

of metabolic activation. 

Acceptable/Guideline 

870.5300 1992-/N VITRO 5-80 ~1 g/m L in DMSO both 42332101 Weakly mutagenic in the 

MAMMALIAN CELL in the presence and absence presence of metabolic 

GENE MUTATION of rat liver metabolic activation 

TEST activation (± S9). 

Acceptable/Guideline 

870.5395 1992-MAMMALIAN mg/kg/day = 250, 500, or 42312001 Negative 

ERYTHROCYTE 1000 (males) or 375, 750, or 

MICRONUCLEUS 1500 (females) single oral 

TEST gavage 

Acceptable/Guideline 

870.7485 1993-METABOLISM mg/kg/day = 42994801 Tem1inal distribution data 

AND Low dose: 5 showed no significant 

PHARMACOKINETICS residual activity in tissues 

-RAT Repeated low dose: 168 hrs oost-dose for both 

Page 19 of21 
Table 3.B Subchronic, Chronic and Otbcr Toxicity Prolile-Diphenylamine Technical 

C OLN Study Type Dose Levels MRIO Results 

5 for 14 days, the low and high ora l dose 

groups: urine was the major 

Single high dose: 750 route for excretion. 

Acceptablc/G u idel ine Recovery after 168 hrs: 

single/repeated low dose= 

urine 68-81 % (both sexes) 

single high dose=73-74% 

Male rais excreted a greater 

percentage of diphenylamine 

derived activity at the low 

dose, wh ile female rats 

showed greater excretion in 

foccs at this dose. At the 

high dose, the percentage 

eliminated in urine was 

equivalent in both males and 

females. 

Attachment 4. International Residue Limit Status (Diphenyhtmine (038501 ; 09/ 17/20 15) 

Table 4. Summary of US and International Tolerances and Maximum Residue Limits 

Residue Defi11itio11: 

us Canada Mexico' Codex2 

40 CFR 180.190: N- Diphenylarnine 

Plant/Livestock: Diphenylarn ine phenylbenzenarnine 

Commodity Tolerance (ppm) !Maxi11111111 Residue Limit (111?.lkg) 

us Canada Mexico' Codex2 

Apple, wet pornace 30 5 10 apple Po 

Apple from preharvest or postharvest 10 

use, including use of irnpreP,nated wraps 0.5 apple juice PoP 

Cattle, fat 0.01 

Cattle, liver 0.1 0.05 

Cattle. meat byproducts. except liver 0.01 0.0 I (*) kidney 

Cattle, meat 0.01 0.0 I (*) (fat) 

Goat, fat 0.01 

Goat, liver 0.1 

Goat. meat byproducts, except liver 0.01 

Goat, meat 0.01 

Horse, fat 0.0 1 

Horse, liver 0.1 

Horse, meat byproducts. except liver 0.0 1 

Horse. meat 0.01 

Milk 0.0 1 0.0 1 (*) 

Pear (postharvest) 5 

Sheep. fat 0.01 

Sheep, liver 0.1 

Sheep, meat byproducts, except liver 0.01 

Sheep, meat 0.01 

MRls wit// NO US Equivalent 

Page 20of2 1 
Table 4. Summa ry of US and International Tolerances and Maximum Residue Limits 

Residue De{i11itio11: 

us I Canada I Mexico1 I Codex2 

Pear I I I I 5 Po 

Completed: M. Negussie; 09/25/ 15 1 Mexico adopts US tolerances and/or Codex MRLs for its export purposes. 1 * = absent at the limit of quantitation; Po = postharvest treatment, such as treatment of stored grains. PoP = 

processed postharvest treated commodity, such as processing of treated stored wheat. (fat)= to be measured on the 

fat portion of the sample. MRLs indicated as proposed have not been finalized by the CCPR and the CAC. 

Page 21 of21