UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

MEMORANDUM 

SUBJECT: 

June 22, 2011 

OFFICE OF CHEMICAL SAFETY 

AND POLLUTION PREVENTION 

Summary of Human Health Effects Data for the o-Benzyl-pChlorophenol (OBPCP) Registration Review Decision Document. 

PC Coders): 062201 ,062202,062203 DP Barcode(s)/No(s): D383100, D389630 

Decision No.: 440916 Registration Numbers: 

Refer to Appendix C 

Petition No(s).: NA Regulatory Action: Human Health Registration 

Review 

Risk Assess Type: Multiple Chemicals Case No(s).: 2045 

TXRNo.:NA 

MRID No(s).: NA 

FROM: 

TO: 

THRU: 

CAS No(s): 120-32-1,35471-49-9, 3184-65-4 

40 CFR: None 

Nathan Mottl, Biologist .UWW/ /ttc;tt/ 

Risk Assessment and Science Support Branch (RASSB) 

Antimicrobials Division (751 OP) 

Rebecca von dem Hagen, Chemical Review Manager 

Regulatory Management Branch II 

Antimicrobials Division (751 OP) 

Lance Wonnell. Team Leader 

Regulatory Management Branch II / 7 V/ 

Antimicrobials Division (75 1 OP) V#d £1 l 

Nader 

Risk Assessment 

Elkassabany, 

and 

Branch 

Science 

Chief 

Support Branch (RASSB) 

~ 

Antimicrobials Division (751 OP) 

Page 1 of30 
Page 2 of 30 

EXECUTIVE SUMMARY 

 The Antimicrobials Division (AD) Registration Review Team has evaluated the status 

of the human health assessments for the o-benzyl p-chlorophenol (OBPCP) case 

(registration review case 4045). The active ingredients in the OBPCP case include the 

active ingredient o-benzyl-p-chlorophenol (OBPCP) (PC Code 062201), and the 

potassium and sodium salts of OBPCP [potassium o-benzyl-p-chlorophenate (PC Code 

062202) and sodium o-benzyl-p-chlorophenate (PC Code 062203)]. OBPCP and its salts 

are used as disinfectants, fungicides/fungistats, tuberculocides, sanitizers, virucides, 

bacteriocides/bacteriostats, algaecides, and microbicides/microbiostats (slime forming 

bacteria, fungi and algae). OBPCP and its salts are used in a variety of different major 

antimicrobial use categories including: agricultural premises and equipment; commercial, 

institutional and industrial premises; food handling processing equipment and premises; 

industrial processes and water systems; medical premises and equipment; and residential 

and public access premises. 

OBPCP and its salts were initially registered as a pesticide in the United States in 

February 1948 as a hard non porous surface disinfectant and deodorizer for use in schools, 

hotels, theatres, stores and office areas. The active ingredient OBPCP has 38 registered 

products; potassium 2-benzyl-4-chlorophenate salt has three registered products; and 

sodium 2-benzyl-4-chlorophenate has five registered products. OBPCP and its salts are 

primarily used as a hard non porous surface disinfectant and deodorizer in agricultural 

premises and equipment, commercial, institutional and industrial premises, food handling 

processing equipment and premises, and residential and public access areas such as horse 

stables, meat and poultry processing plants, mushroom houses, greenhouses, households, 

and animal kennels. It is also used as a hard non porous surface disinfectant in medical 

areas and equipment such as non conductive floors, beds, wall and floors and to pre-clean 

instruments and other medical equipment prior to terminal sterilization. There are some 

public health claims for this pesticide when used as a disinfectant. Unlike the other active 

ingredients in the case, sodium o-benzyl p-chlorophenate is also used for industrial 

process and water systems (recirculating cooling water systems and air washers). OBPCP 

and its salts are formulated as soluble concentrates, ready-to-use solutions, and 

impregnated materials. 

In addition to the registered disinfectant uses, it should be noted that the technical 

product (EPA Reg No. 39967-5 formulated at 98.6% active ingredient) could also be 

formulated as a preservative in metalworking fluids, rubber goods, leather, textiles, 

upholstery fabrics, and carpets and for water treatment uses such as air washer water, 

cooling tower water, sewage systems, grease traps, drains, and human drinking water 

equipment. The preservative uses listed on the technical product are not listed on any enduse product labels. The current guideline studies for all the registered product uses are 

presented in Table 1. If the registrant intends to support these uses, the Agency will need 

additional data (Table 6) to support the preservative uses of OBPCP and its salts. The 

current data requirements for the end use product uses are presented in Table 5. The 

Agency also cannot conduct a risk assessment for the preservative uses on the technical 

product label, since these uses are not on any end-use products and the technical product 

does not include application rates. 
Page 3 of 30 

 EPA examined the hazard and exposure databases for the OBPCP case to determine 

whether changes in science policy or deficiencies in the databases materially affected the 

overall risk picture. A Registration Eligibility Decision (RED) document for o-benzy pchlorophenol was signed on December 1995. EPA has established tolerances under 40 

CFR 180.940c for use in food processing equipment and utensil with a not to exceed limit 

of 320 ppm. FDA currently has cleared OBPCP as an indirect additive in food contact 

sanitizing solutions (21 CFR §178.1010) that can be used for food processing equipment 

and utensils. According to the RED pesticide fact sheet, disinfectants registered for use in 

federally inspected meat, poultry, and egg processing plants, as well as food preparation, 

storage, and serving establishments/areas, require that food products and packaging 

materials are removed or carefully covered prior to application and that a potable water 

rinse is employed after treatment (U.S. EPA 1995). For registration review, EPA expects 

that indirect exposure to surface cleaners would trigger an initial Tier I dietary screeninglevel assessment. Therefore, EPA will conduct a Tier 1 dietary screening-level assessment 

for food processing equipment and utensils as well as an assessment of indirect food 

contact from countertops in residential homes. 

No new sub-chronic, chronic toxicity data for OBPCP has been submitted to the 

Agency since reregistration. The purpose of this screen is to determine whether sufficient 

data are available to support registration review, whether new human health assessments 

are needed to support registration review, and to report why the Agency feels it may 

appropriate to conduct new risk assessments under the registration review process. After 

reviewing the end-use labels the Agency anticipates the need for the following studies. 

Table 1: Data Requirements of OBPCP 

Guideline No. Study Needed

Special Study* Dermal Sensitization Threshold Quantification

870.3465 90-day Inhalation Toxicity

870.3800 Reproduction and Fertility Effects

870.7800 Immunotoxicity 

875.1200 Dermal Exposure – Indoor

875.1400 Inhalation Exposure - Indoor 

875.1600 Data Reporting and Calculations

875.1700 Product Use Information 

875.2300 Indoor Surface Residue Dissipation

875.2800* Description of Human Activity

875.3000 Non-dietary Ingestion

*Additional data needs based on preservative uses. Also, more than one exposure study may be needed for each 

guideline number. 

 Additional exposure data would be needed to support the uses for the technical product 

(formulated at 98.6% active ingredient). Since it could be also be formulated as a 

preservative in metalworking fluids, rubber goods, leather, textiles, upholstery fabrics, and 

carpets and for water treatment uses such as air washer water, cooling tower water, 

sewage systems, grease traps, drains, and human drinking water equipment. The registrant 
Page 4 of 30 

would need additional studies. The Agency cannot conduct risk assessments since there 

are no existing application rates to assess exposure. 

The potential occupational handler exposure scenarios identified by the Agency after 

review of the end-use labels include (1) open-pour loading of liquid formulations, (2) 

applying disinfectant by hand wiping surfaces, (3) applying the disinfectant by hand by 

dipping tools/implements into dilute disinfectant solution, (4) applying the disinfectant by 

mopping surfaces, (5) applying the disinfectant with hand-held, high pressure spray 

equipment, (6) applying the disinfectant with hand-held, low pressure spray equipment, 

(7) applying with a trigger pump sprayer, (8) applying with an aerosol can and (9) 

applying the disinfectant with a wet-mist fogger. 

 There are potential postapplication exposures scenarios based on the review of the 

end-use labels. There are potential inhalation concerns to persons reentering areas that 

have been treated with OBPCP, especially following wet-mist fogging applications and 

other applications in enclosed areas. Dermal and incidental oral postapplication exposures 

may occur from children crawling on treated floors, or hand-to-mouth exposure from 

counter tops and floors. 

Section 1. Chemical Identity 

 OBPCP is a phenolic compound in which there is a hydroxyl (-OH) and chloro (Cl) 

group attached to one of the rings at the ortho and para positions (see figure on Table 2). 

OBPCP is a white to light grey solid. It has a boiling point of 175oC and a melting point of 

49 oC. OBPCP is lipophilic and is only slightly soluble in water with a density of 7 mg/L 

and log Kow of 4.3. The registered products contain 0.02-98.6% active ingredient (ai.). 

Table 2 presents the chemical identity of OBPCP. 

Table 2. Chemical Identity

Common 

Name

o-Benzyl p-chlorophenol, potassium obenzyl-p-chlorophenate, and sodium obenzyl p-chlorophenate

Synonyms ortho-Benzyl-para-chlorophenol, 

chlorophen, 2-benzyl 4-chlorophenol

PC Code 062201,062202,062203

CAS registry 

number

120-32-1, 35471-49-9, 3184-65-4

Registration 

Review Case 

No.

2045

Structure
Page 5 of 30 

Vapor 

Pressure

0.075 mm Hg at 100 o C for OBPCP

Section 2. Toxicology 

 The Agency has reviewed toxicity studies submitted for the three active 

ingredients, o-benzyl-p-chlorophenol (OBPCP), sodium o-benzyl-p-chlorophenate 

(Na

+OBPCP) and potassium o-benzyl-p-chlorophenate (K+OBPCP). The toxicological 

databases for these three active ingredients are currently comprised of published and 

unpublished studies either submitted to the Agency or obtained directly from the 

published open literature during the registration process. 

For the Reregistration Eligibility Decision (RED) published in 1995, the Office of 

Pesticide Programs’s Health Effects Division (HED) determined that toxicity studies 

conducted with OBPCP may be used to support registration of the phenate forms 

(Na+OBPCP and K+OBPCP) of this chemical. This decision is based upon the rapid 

dissociation of the sodium and potassium salts of OBPCP to the phenol moiety in vivo, 

indicating biologically equivalent activities for OBPCP, Na+OBPCP, and K+OBPCP. 

However, this guidance does not preclude the Agency from requiring, pursuant to FIFRA 

section 3(c)(2)(B), additional data it deems necessary to assess the risks or benefits of an 

active ingredient, at a later time. 

Acute Toxicity 

Table 3 summarizes the results of the acute toxicity studies conducted with the 

technical grade active ingredient (TGAI), OBPCP. 

 

Table 3: Acute Toxicity Studies for OBPCP (TGAI, 75-95%)

STUDY (Guideline No.) MRID 

No(s).

RESULTS TOXICITY 

CATEGORY*

Acute Oral(81-1) 00131367

92008008

LD50 = males: 4462 mg/kg 

LD50 = females: 3852 mg/kg

LD50 = combined: 4147 mg/kg

III

Acute Dermal(81-2) 00130937

92008009

LD50 > 2000 mg/kg III

Acute Inhalation (81-3) 00130938

92008010

LC50 = males: 2.60 mg/L 

LC50 = females: 2.43 mg/L

LC50 = combined: 2.50 mg/L

IV

Primary Eye Irritation (81-4) 00131368

92008011

Severely irritating

PIS score = 79 at 72 hours

I

Primary Dermal Irritation (81-5) 45460201 Severe Irritation/Corrosion

(Self-validated)

I

Skin Sensitization (81-6) 45424201 Skin Sensitizer NA

*Assigned toxicity categories are based on the acute toxicity study results and reflect the most current 

categories as identified in the U.S. Environmental Protection Agency, Label Review Manual, updated 

August, 2010 (http://www.epa.gov/oppfead1/labeling/lrm/\).

Dermal Sensitization 
Page 6 of 30 

 The delayed contact hypersensitivity potential of OBPCP has been evaluated in albino 

guinea pigs using the closed patch (Beuhler) method. In this study, erythema was 

observed at induction and challenge sites treated with OBPCP as well as subcutaneous 

hemorrhaging (induction and challenge sites), blanching (induction sites), necrotic looking 

skin (induction sites), desquamation (challenge sites) and fissuring (challenge sites). 

Based on the increased incidence, duration, and severity of reactions in the test group to 

the challenge application, OBPCP is considered to be a dermal sensitizer. 

 Although an acceptable dermal sensitization study is available for OBPCP, the Agency 

anticipates needing additional data to quantitatively address skin sensitization for risk 

assessment purposes during the registration review process. Severe dermal irritation and 

allergic type reactions in humans have been reported in the available incident data bases 

following exposure to OBPCP and or its sodium and potassium salts. The symptoms 

included skin depigmentation, itching, pain, swelling, blister, hives, and erythema. 

Additionally, “Mice demonstrated statistically significant dose-dependent contact 

hypersensitivity responses to OBPCP with or without adjuvant pretreatment.” according to 

a published literature study by Stern, 1991. Furthermore, repeated dermal exposure 

(direct contact) is considered the primary route of exposure for some residential use 

scenarios (e.g., textiles and clothing). As suggested in the FIFRA Scientific Advisory 

Panel Meeting (SAP, 2004), it is important to quantitatively assess dermal sensitization 

when dermal exposure is the primary route of concern based on product use patterns and 

when there is no appropriate way to label products for residential uses, specifically, 

textile/clothing treatments. 

 Therefore, the Agency anticipates the need for a special study conducted with either 

OBPCP, Na+OBPCP or K+OBPCP that provides quantitative data and an assessment of 

dose-response for both the initiation and elicitation phases of skin sensitization. The 

purpose of this study is to identify a threshold level for quantification of dermal 

sensitization to OBPCP or its’ salts. 

Mutagenicity 

 Three acceptable mutagenicity studies are available in the OBPCP data base: (1) a 

gene mutation assay in Salmonella typhimurium, (2) an in vivo bone marrow micronucleus 

assay in mice, and (3) a chromosomal aberration study in Chinese Hamster ovary (CHO) 

cells. OBPCP tested negatively under the conditions of each of these studies. The 

mutagencity battery for OBPCP is considered complete. 

 OBPCP (96.9% a.i.) was tested for its potential to induce reverse mutations in 

Salmonella typhimurium strains TA1535, TA1537, TA98 and TA100 (MRID 41287501). 

The exogenous metabolic activation mixes were derived from either hamster or rat liver 

S9 homogenates (all strains were tested with each). OBPCP was tested up to levels of 

cytotoxicity in all tested bacterial strains, ranging from 0.3 to 33 μg/plate without 

metabolic activation and from 1 to 100 μg/plate with metabolic activation. OBPCP failed 

to induce a mutagenic response, either with or without metabolic activation 

 In an in vivo bone marrow micronucleus assay (MRID 41572801), OBPCP (97.9% 

a.i.) was tested in mice at dose levels up to and including 2000 mg/kg. The animals 
Page 7 of 30 

showed clear signs of toxicity, although there was only slight evidence that the test 

chemical reached the target organ. OBPCP was negative for clastogenic activity on bone 

marrow erythrocytes under the conditions of the study. 

 In a Chinese Hamster ovary (CHO) assay (MRID 43322901), non-activated and S9-

activated cell cultures were exposed to OBPCP (99.7% a.i.) at concentrations of 0 

(control), 4, 8, 15, 30 or 60 μg/ml (-S9), or 0 (control), 1.3, 2.5, 5, 10 or 20 μg/ml (+S9). 

The cells were then examined for structural chromosomal aberrations 20 hours after 

initiation of treatment. The highest dose tested (HDT) caused excessive toxicity (complete 

inhibition), but there were no increases in cytogenetic effects at any dose tested. 

 

Sub-chronic Toxicity 

 OBPCP was tested in subchronic gavage studies in both rats and mice (MRID 

40376301, 41248202, 41462401). The rodents were dosed 5 days/week for 13 weeks at 

the following dose levels: rats - 0 (control), 30, 60, 120, 240 or 480 mg/kg/day; mice- 0 

(control), 500, 650, 800 or 1000 mg/kg/day. In rats, the NOEL was 120 mg/kg/day and 

the LOEL was 240 mg/kg/day based on clinical signs of toxicity, changes in clinical 

chemistries, decreases in thymus weights, increases in kidney weights, chronic 

nephropathy and thymic lymphoid depletion. In mice, a NOEL was not established 

because kidney lesions were present at the lowest dose tested (LDT), 500 mg/kg/day. 

Therefore, the toxic effects observed at the LOEL of 500 mg/kg/day in mice included 

increased mortality, increases in clinical signs of toxicity, increases in liver weights, 

decreases in kidney weights, increases in renal lesions (necrosis, casts, inflammation and 

regeneration of renal tubules) and necrosis of thymic lymphocytes. Both studies were 

classified as core supplementary because only minimal summary data tables were 

provided to support the text of the report. In addition, neither clinical chemistry 

parameters nor urinalysis parameters were measured in the mouse study. However, these 

studies may be upgraded if the individual animal data are provided as well as table legends 

for clarification of the assay results. 

 

 In a 21-day dermal toxicity study (MRID 41248201), OBPCP (5% a.i.) was tested on 

New Zealand rabbits at dose levels of 0 (control), 1, 5 or 25 mg/kg/day. The LOEL for 

systemic toxicity was not established and; therefore, the NOEL for systemic effects was 

25 mg/kg/day, the highest dose tested (HDT). The NOEL for dermal effects was 1 

mg/kg/day, and the LOEL for dermal effects was 5 mg/kg/day based on acanthosis, 

hyperkeratosis, parakeratosis, dermatitis, and scabs. There were some ulcerated areas in 

the 25 mg/kg/day dose group. According to EPA’s review of these data, this study 

satisfied the 21-day dermal guideline 82-2 requirements and was classified core guideline 

under Subdivision F Test Guidelines (U.S. EPA, 1989). 

 As a result of the potential for inhalation exposures to OBPCP or the 

sodium/potassium phenate forms of OBPCP from fogging, trigger spray and aerosol 

applications, the Agency is requiring a 90-day inhalation toxicity study conducted with 

either OBPCP, Na+OBPCP, and K+OBPCP to establish short- and intermediate-term 

toxicity inhalation endpoints for risk assessment purposes. 
Page 8 of 30 

Immunotoxicity 

 Based upon decreased thymus weights and thymic lymphoid depletion which were 

noticed in the 90-day oral rat study conducted with OBPCP (MRID 40376301, 41248202, 

41462401), EPA has concerns about the potential immunotoxicity of this chemical.

Reported incidents of autoimmune thrombocytopenia, nose/mouth bleeding, aplastic 

anemia and leukemia in humans following exposure to OBPCP also raises concern for 

immunotoxicity. As a result, EPA is requiring an immunotoxicity study conducted with 

either OBPCP, Na+OBPCP, or K+OBPCP. 

Developmental 

 In a rat developmental toxicity study (MRID 00143775), OBPCP (97.8% a.i.) was 

administered via gavage to Sprague-Dawley rats at dose levels of 0 (control), 100, 300 or 

900 mg/kg/day on days 6-15 of gestation. Statistically significant decreases in body 

weight were observed at all dose levels, decreases in mean food consumption were 

observed in the mid- and high-dose groups and increased water intake was observed in the 

high dose group. Therefore, the maternal NOEL was considered to be less than 100 

mg/kg/day (the lowest dose tested) and the LOEL is 100 mg/kg/day based on statistically 

significant decreases in body weight gain. No developmental toxicities were observed in 

the fetuses; therefore, the developmental toxicity LOEL was not established in this study 

and the developmental toxicity NOEL was 900 mg/kg/day (the highest dose tested). 

 In the second rat developmental toxicity study (MRID 00145836, 00161231, 

92007001), OBPCP (96.8% a.i.) was administered via gavage to Wistar rats at dose levels 

of 0 (control), 15, 75 or 375 mg/kg/day on days 6-15 post coitum. At 375 mg/kg/day, 3 of 

the dams died. There was also a decrease in maternal mean body weight gains (47%), and 

corrected body weight gains (40%) when compared to controls, as well as an increase in 

the number of animals with mucoid feces. The NOEL for maternal toxicity was 75 

mg/kg/day and the LOEL for maternal toxicity was 375 mg/kg/day based on decreased 

body weight gain, increased mortality and increased mucoid feces. At 375 mg/kg/day, 

there was a decrease in group mean fetal weights (94% of control). Therefore, the NOEL 

for developmental toxicity was 75 mg/kg/day and the LOEL for developmental toxicity 

was 375 mg/kg/day based on a decrease in mean fetal weights. 

 In a rabbit developmental toxicity study (MRID 00143774, 40988201, 41003901), 

OBPCP (97.8% a.i.) was administered to New Zealand White rabbits via gavage at 0, 10, 

30 or 100 mg/kg/day on days 6-19. No maternal toxicity was observed at any dose level. 

The maternal toxicity NOEL was equal to or greater than 100 mg/kg/day, the highest dose 

tested. However, 50% mortality was observed at 150 mg/kg/day and 100% mortality was 

observed at 200 and 300 mg/kg/day in the pilot study. Therefore, 100 mg/kg/day is 

considered adequate for testing in the main study. An increase in post-implantation loss 

(primarily attributed to late resorptions) was observed in the high dose group when 

compared with controls, which was outside the range of the historical control data. 

However, the litter sizes were comparable between the control and the high dose group 

which was indicative of a minimal effect. Therefore, the NOEL for developmental 

toxicity was 30 mg/kg/day and the LEL for developmental toxicity was 100 mg/kg/day 

based on increases in post-implantation loss and late resorptions. 
Page 9 of 30 

Reproductive Toxicity 

 Currently, there is no available reproduction toxicity study for OBPCP or its sodium 

and potassium salts. According to the RED (1995), results of the rabbit developmental 

toxicity study indicated a potential concern for reproductive effects following 

administration of OBPCP. This study showed an increase in post-implantation loss and 

late resorptions in the high dose group when compared to controls. In addition, the 

developmental toxicity study conducted in Wistar rats showed decreased fetal body 

weights. Furthermore, one reproductive incident has been reported in the OPP incident 

data system involving a pregnant woman; her baby was born 6 weeks early with too much 

fluid in the abdomen and as a result of this condition, died. To evaluate these reproductive 

concerns, a 2-generation reproduction toxicity study conducted with OBPCP is required. 

 

Chronic Toxicity and Carcinogenicity 

Administration of OBPCP (97% a.i.) in corn oil via gavage to B6C3F1 mice (males and 

females: 0, 120, 240 or 480 mg/kg/day) in a two-year carcinogenicity feeding study 

(MRID 42279302) resulted in a significant dose-related, increased trend and statistically 

significant pair-wise comparisons of all dose groups with the control group for renal 

tubule tumors (adenomas and/or combined adenomas/carcinomas, with carcinomas 

contributing a substantial portion of the total incidence) at p < 0.05 in male mice. There 

was also a significant difference in the pair wise comparison of the 120 mg/kg/day dose 

group with the controls for renal tubule adenomas at p < 0.05. In this study, incidences of 

these (rare) renal tubule tumors in male mice exceeded historical control incidences for all 

doses tested. The highest dose tested (480 mg/kg/day) was considered excessive based 

upon increasing trends in mortality, clinical signs of toxicity, lower mean body weights, 

and severe microscopic lesions/histopathology in a variety of organs (kidney renal 

nephropathy, fibrous osteodystrophy, myocardial degeneration, and coagulative necrosis 

and inflammation in the liver). However, dosing was considered adequate at the mid-dose 

for assessing the carcinogenic potential of OBPCP in mice based upon an increasing but 

acceptable trend in mortality in both sexes with increasing dose, clinical signs of toxicity, 

changes in organ weights, increased incidence/severity of kidney nephropathy and 

increased incidences of non-neoplastic lesions in a variety of organs at a lesser extent than 

in the high dose group. A chronic systemic toxicity NOEL could not be established for 

mice because there were treatment-related effects at the lowest dose level. The chronic 

systemic toxicity LOEL was 120 mg/kg/day based upon treatment-related increases in 

mortality in both sexes, clinical signs of toxicity in both sexes (emaciation, abnormal 

posture, rough hair coat and hypoactivity), decreased body weights in males, changes in 

organ weights in both sexes (decreased absolute and relative kidney and thymus weights), 

forestomach hyperplasia and ulcer in both sexes, glandular stomach mucosa 

mineralization in both sexes, fibrous bone osteodystrophy in both sexes, and renal 

nephropathy in both sexes. 

 In a two-year chronic toxicity/carcinogenicity feeding study (MRID 42279301), 

OBPCP (97% a.i.) was administered (males: 0, 30, 60 or 120 mg/kg/day; females: 0, 60, 

120, 240 mg/kg/day) in corn oil via gavage to F344/N rats for two years. Rare, renal 

transitional cell carcinomas in both mid- and high dose female rats (one in each group) 
Page 10 of 30 

were observed. There was no occurrence of these tumors in concurrent controls of either 

sex or in any of 1,068 historical control females. There was also one renal tubule 

adenoma in a high dose female and one renal tubular carcinoma in a high dose male; 

however, these tumor types in rats were within the range of historical controls and are not 

considered treatment-related. Dosing in this study was considered adequate for 

carcinogenicity testing in rats based upon treatment-related increases in incidences of 

several microscopic lesions (dose-related increase in incidence/severity of renal 

nephropathy, hyperplasia of the kidney tubule and transitional cells, hyperplasia of the 

parathyroid gland, and fibrous osteodystrophy of the cranium and femur); increases in 

kidney weights; increases in supporting urinalysis values (coproporphyrin, protein, and 

alkaline phosphatase); decreases in galactosidase activities; and increases in yellow 

staining of the urogenital area. The chronic systemic toxicity LOEL was 30 mg/kg/day 

(lowest dose tested in male rats) based upon increased incidence/severity of kidney 

nephropathy and increased urinary coproporphyrin. A chronic systemic toxicity NOEL 

could not be established because of the increased incidence of kidney nephropathy in male 

rats observed at 30 mg/kg/day compared to controls. (MRID 42279302; this is Tier 3 data 

which were not required by the Agency. The study was performed by NTP and submitted 

as 6(a)(2) data). 

Cancer Classification 

 On September 5, 1995, the Carcinogenicity Peer Review Committee (CPRC) 

classified OBPCP as a Group C - possible human carcinogen and that for the purpose of 

risk characterization, the committee recommended the RfD approach for quantitation of 

human risk. This determination was based upon the compound-related increases in renal 

tubule tumors at all doses in male B6C3F1 mice (combined adenoma/carcinoma, with 

carcinomas contributing a substantial portion 33-50% of the total incidence) and increases 

in renal transitional cell carcinomas at the mid- and high-doses in female F344/N rats 

(with none in any of the 1, 068 historical control females as well as concurrent control 

animals). Renal tubular carcinomas in the mouse and renal transitional cell tumors in the 

rat are rare. In addition to the absence of a specific mechanism(s) leading to formation of 

these rare renal tumors in mice and rats, there were no structural analogs of OBPCP that 

have been tested for carcinogenic potential and no apparent genotoxicity concern from the 

mutagenicity data submitted to support registration of this active ingredient as a pesticide. 

Metabolism 

 Metabolism data are not available for the active ingredients, OBPCP, Na+OBPCP, or 

K

+OBPCP. For antimicrobial pesticides, metabolism studies are "required only if the 

Agency determines that additional information on the metabolism of the chemical(s) are 

necessary to clarify unusual effects observed in chronic or reproduction studies or to 

clarify issues concerning structure activity relationships”. For OBPCP, Na+OBPCP, or 

K

+OBPCP, no issues were identified that warrant the need for metabolism data at this 

time. 

Dermal Penetration 
Page 11 of 30 

 A dermal absorption study (MRID 43313401) for OBPCP is available. This study was 

conducted with OBPCP (5% a.i. formulation) administered at 5, 50, and 500 μg/cm2for 1, 

4, 10 hours with a 168 hour collection period. The total quantity and percent OBPCP 

absorbed increased with time and dose, with most of the test substance accumulating in 

the body during the first 10 hours. At 168 hours, essentially all administered OBPCP was 

excreted in the uring and feces. This study has been classified as acceptable and indicates 

that OBPCP reacts in such a way that is typical of a chemical which destroys the integrity 

of the stratum corneum of the skin (outer layer of the epidermis). Table 4 summarizes 

these results. 

Table 4: Dermal Penetration of OBPCP

% Absorption of 5% Formulation From Several Dose Levels at Various Time Points

Dose Time 5 μg/cm250 μg/cm2500 μg/cm2

1 hour 7.7% 6.19% 5.42%

4 hours 15.82% 14.69% 18.96%

10 hours 23.93% 26.31% 29.15%

168 hoursa

26.10% 51.61% b41.45%

a Animals kept longer than 10 hours were washed at 10 hours. 

The 168 hours, 50μg/cm2 value was considered the most appropriate to use for risk assessment purposes. 

b Therefore, the dermal absorption of OBPCP is 51.6%.

Section 3. Dietary Assessment 

Dietary 

OBPCP currently has a tolerance exemption under 40 CFR 180.940c for use in food 

processing equipment and utensil with a not to exceed limit of 320 ppm. FDA has also 

cleared o-benzyl-p-chlorophenol as an indirect additive in food contact sanitizing 

solutions (21 CFR §178.1010) that can be used for food processing equipment and 

utensils. For registration review, EPA expects that indirect exposure to surface cleaners 

would trigger an initial Tier I dietary screening-level assessment. Therefore, EPA will 

conduct a Tier 1 dietary screening-level assessment for food processing equipment and 

utensils as well as an assessment of indirect food contact from countertops in residential 

homes. EPA anticipates the need for residue data for countertops to assess incidental oral 

exposure from the resulting indirect dietary exposures. Based on D310957, the EPA 

estimated that a worst-case dietary exposure to be 320 ppm assuming no washing or 

rinsing. 

Drinking Water 

 Since OBPCP is used in industrial cooling water towers and air washers, the Agency 

expects that it could migrate to groundwater and surface water and then on to drinking 

water. Although likely to be infrequent, dietary exposures via drinking water may occur 

in the event of a down-the-drain discharge. The contaminated water could pass through 

wastewater treatment facilities into the drinking water or may be discharged directly to 

surface water which is later treated. However, at this time there are no environmental fate 

data to determine whether OBPCP can pass through wastewater treatment facilities into 

drinking water or migrate into residential groundwater wells as a result of its current use 

patterns. Since the product is used in commercial recirculating cooling water systems, the 
Page 12 of 30 

Agency anticipates that the effluent wastewater could discharge directly to surface water. 

As a result, the Agency would anticipate the need to model environmental concentrations 

and develop a drinking water risk assessment. 

Section 4. Aggregate and Cumulative Exposure 

In examining aggregate exposure, EPA takes into account the available and reliable 

information concerning exposures to residues in food and drinking water, and nonoccupational pesticide exposures. EPA expects that the dietary and residential risks will 

need to be aggregated. Section 408(b)(2)(D)(v) 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 OBPCP has a common mechanism of toxicity with other 

substances or how to include this pesticide chemical in a cumulative risk assessment. 

Section 5. Occupational/Residential Exposure 

There is potential short- and intermediate-term exposure to occupational workers for 

applications such spraying, mopping, and wiping from the hard surface disinfectant use to 

hard surfaces (such as counter tops), medical and agricultural equipment, animal and 

agricultural premises, green houses and floors. The potential occupational handler 

exposure scenarios identified by the Agency after review of the labels include (1) openpour loading of liquid formulations, (2) applying disinfectant by hand wiping surfaces, (3) 

applying the disinfectant by hand by dipping tools/implements into dilute disinfectant 

solution, (4) applying the disinfectant by mopping surfaces, (5) applying the disinfectant 

with hand-held, high pressure spray equipment, (6) applying the disinfectant with handheld, low pressure spray equipment, (7) applying with a trigger pump sprayer, (8) 

applying with an aerosol can and (9) applying the disinfectant with a wet-mist fogger. 

Product use data will be essential to categorize the uses and equipment necessary to refine 

these risk assessments. The Agency expects that both the dermal and inhalation routes will 

need to be assessed. 

 

 In addition to the registered disinfectant uses, it should be noted that the technical 

product (formulated at 98.6% active ingredient) also could be formulated as a preservative 

in metalworking fluids, rubber goods, leather, textiles, upholstery fabrics, and carpets and 

for water treatment uses such as air washer water, cooling tower water, sewage systems, 

grease traps, drains, and human drinking water equipment. However, application rates and 

end-use product uses are not identified on the existing end-use labels. Data would be 

needed to support these use patterns and additional risk assessments would need to be 

conducted. 

 There are potential inhalation concerns to persons reentering areas that have been 

treated with OBPCP, especially following wet-mist fogging applications and other 

applications in enclosed areas. Dermal and incidental oral postapplication exposures may 

occur from children crawling on treated floors, or hand-to-mouth exposure from counter 

tops and floors.
Page 13 of 30 

Section 6. Incidents 

The OPP Incident Data System (IDS) has reported 122 human incidents attributable to 

o-benzyl-p-chlorophenol. Most of the incidents are classified as moderate incidents. 

Severe dermal irritation and allergic type reactions were reported. The symptoms 

included skin depigmentation, itching, pain, swollen, blister, hives, and erythema. 

Reported symptom related to inhalation exposures included nasal irritation, ulcerated nasal 

membranes, burning throat, blisters in throat, hoarse coughing, shortness of breath, 

coughing, dyspnea, chest pain, and chest tightness. 

Acute systemic effects for workers included nausea, dizziness, stomach ache, 

headache, vertigo, and soft stool. For longer exposures over 6-months, workers 

complained of no or low appetite, weakness, and liver damage. Severe autoimmune 

thrombocytopenia, red skin rashes, nose/mouth bleeding, aplastic anemia and leukemia 

was also reported. One incident that raised a reproductive concern, involved a pregnant 

woman. The baby was born 6 weeks early with too much fluid in the abdomen. The baby 

died as a result.

Section 7. Anticipated Data Needs 

The Antimicrobial Division (AD) anticipates requiring further exposure and toxicity 

studies for OBPCP for registration review. Table 5 lists the data needs based on the uses 

of the current registered end-use labels. Table 6 list additional data requirements based on 

uses on the registered technical products. Note that technical product has additional uses 

that are not currently presented on the end-use labels such as formulation as a preservative 

in metalworking fluids, rubber goods, leather, textiles, upholstery fabrics, and carpets and 

for water treatment uses are listed as registered uses on the manufacturing use products 

but are not supported by uses and applications on end-use products. 

Table 5: Exposure Data Needs Based on End Use Labels 

Study Needed Guideline Rationale (also see Appendix A and B)

90-day Inhalation Toxicity 870.3465 As a result of inhalation exposures to high pressure sprays, 

fogging, trigger sprays and aerosols; the Agency anticipates 

that a 90-day inhalation study will be needed to develop 

short- and intermediate- toxicity inhalation endpoints. 

Reproduction and Fertility 

Effects

870.3800 As a result of significant increase in post-implantation loss 

in the high dose group, a human incident, and chronic 

dietary exposure a reproductive study is needed.

Immunotoxicity 870.7800 Based upon decreased thymus weights and thymic 

lymphoid depletion which were noticed in the 90-day oral 

rat study conducted with OBPCP (MRID 40376301, 

41248202, 41462401), EPA has concerns about the 

potential immunotoxicity of this chemical. Reported

incidents of autoimmune thrombocytopenia, nose/mouth 

bleeding, aplastic anemia and leukemia in humans 

following exposure to OBPCP also raises concern for 

immunotoxicity.

Indoor Exposure 

(Fogging)

875.1200 (Dermal)

875.1400 (Inhalation)

875.1600 (Data Reporting)

Exposure may occur while using a wet mist fogger for 

agricultural premises.
Page 14 of 30 

Indoor Exposure 

(Trigger Spray)

875.1200 (Dermal)

875.1400 (Inhalation)

875.1600 (Data Reporting)

Exposure may occur while spraying with a trigger pump 

cleaning spray in a bathroom, kitchen or other areas of the 

home or office.

Indoor Exposure

(Aerosol Spray)

875.1200 (Dermal)

875.1400 (Inhalation)

875.1600 (Data Reporting)

Exposure may occur while spraying with a aerosol can in a 

bathroom, kitchen or other areas of the home or office.

Indoor Exposure 

(Sponge and Wipes)

875.1200 (Dermal)

875.1400 (Inhalation)

875.1600 (Data Reporting)

Exposure may occur while sponging or wiping disinfectant 

on a hard surface area.

Indoor Exposure

(High Pressure Sprays)

875.1200 (Dermal)

875.1400 (Inhalation)

875.1600 (Data Reporting)

Exposure may occur from high pressure sprays in 

agricultural premises.

Product Use 875.1700 (Handler)

875.2800 (Postapplication)

Product use data will be needed to characterize any 

uncertainties with regard to the application equipment.

Indoor Surface Residue 

Dissipation Data

875.2300 Residue data for countertops would be needed to assess 

dermal and incidental oral exposure and an indirect dietary 

exposure assessment. 

Inhalation Exposure 875.2500 The post application inhalation exposure data will be used 

to assess the residential and/or occupational inhalation risks 

to estimate reentry exposure to fogging from a thermal 

fogger product use. This data is needed to conduct an 

inhalation postapplication assessment.

Nondietary Ingestion 875.3000 The design of the non dietary ingestion exposure study can 

be combined with the Indoor Surface Residue Dissipation 

study (875.2300) to determine the available residue 

leaching from hand-to-mouth behavior on countertops.

Table 6: Additional Data Needs Based on Manufacturing Use Product Use* 

Study Needed Guideline Rationale 

Dermal Sensitization 

Threshold Quantification

Special Toxicity Study The Agency anticipates needing additional data to 

quantitatively address skin sensitization for risk assessment 

purposes during the registration review process. Severe 

dermal irritation and allergic type reactions in animal tests. 

In addition, human incidents have been reported following 

exposure to OBPCP and or its sodium and potassium salts.

The fabric use specifically triggers this special dermal 

sensitization study. A dose response study is needed based 

on the expected prolonged dermal contact associated with 

clothes made out of fabrics impregnated with OBPCP.

Indoor Exposure 

(Sprays)

875.1200 (Dermal)

875.1400 (Inhalation)

875.1600 (Data Reporting)

Exposure may occur from sprays from machinist 

exposures.

Indoor Exposure 

(mixing/loading)

875.1200 (Dermal)

875.1400 (Inhalation)

875.1600 (Data Reporting)

Exposure may occur while pouring preservative in a 

manufacturing setting for metal working fluids, rubber, 

leather, textiles, and cooling water.

Product Use 875.1700 (Handler)

875.2800 (Postapplication)

Product use data will be needed to characterize any 

uncertainties with regard to the application equipment.

Product use data will be needed to characterize any 

uncertainties with regard to post application exposure 

scenarios.

Indoor Surface Residue 

Dissipation Data

875.2300 Residue data for clothing would be needed to assess dermal 

and incidental oral exposure.

Description of Human 

Activity

875.2800 These data will clearly identify the specific equipment used 

to deliver OBPCP to the use site, which in high exposure 

scenarios, such a metal working fluids will allow the 
Page 15 of 30 

Agency to refine its risk assessment. 

Nondietary Ingestion 875.3000 The design of the non dietary ingestion exposure study can 

be combined with the Indoor Surface Residue Dissipation 

study (875.2300) to determine the available residue 

leaching from a child mouthing treated leather clothing 

articles as well as hand-to-mouth behavior on carpets.

*Additional data would be needed to support the uses for the technical product (EPA Reg No. 39967-5 formulated at 

98.6% active ingredient). Since it could be also be formulated as a preservative in metalworking fluids, rubber goods, 

leather, textiles, upholstery fabrics, and carpets and for water treatment uses such as air washer water, cooling tower 

water, sewage systems, grease traps, drains, and human drinking water equipment. The registrant would need additional 

studies. The actual guideline numbers for the exposure studies are similar except for 875.2800 and the dermal 

sensitization study. However, the uses will trigger more than one exposure study per guideline. 

Section 8. Tolerances 

OBPCP currently has a tolerance exemption under 40 CFR 180.940c for use in food 

processing equipment and utensils with a not to exceed limit of 320 ppm. OBPCP is listed 

in 40 CFR 180.940c as the synonym phenol, 4-chloro-2-(phenylmethyl) (CAS Reg No. 

120-32-1).

Section 9. Endocrine Disruption 

As required by FIFRA and FFDCA, EPA reviews numerous studies to assess potential 

adverse outcomes from exposure to chemicals. Collectively, 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

reregistration decision, 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), OBPCP is subject to the endocrine screening part of 

the Endocrine Disruptor Screening Program (EDSP). 

EPA has developed the EDSP to determine whether certain substances (including 

pesticide active 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 statutorily required determinations. Tier 1 consists of a battery of 11 screening assays 

to identify the potential of a chemical substance to interact with the estrogen, androgen, or 

thyroid (E, A, or T) hormonal systems. Chemicals 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. 
Page 16 of 30 

Under FFDCA section 408(p), the Agency must screen all pesticide chemicals. 

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. OBPCP is not among the group of 58 pesticide active ingredients on the 

initial list to be screened under the EDSP. Accordingly, as part of registration review, 

EPA will issue future EDSP orders/data call-ins, requiring the submission of EDSP 

screening assays for OBPCP. For further information on the status of the EDSP, the 

policies and procedures, the list of 67 chemicals, future lists, the test guidelines and the 

Tier 1 screening battery, please visit our website: http://www.epa.gov/endo/.

Section 10. References 

D389630. Benxylchlorophenol (o-Benzyl-p-chlorophenol; Sodium o-Benzyl-pchlorophenate; Potassium o-Benzyl-p-chlorophenate): Revised Toxicology Data 

Summaries for the Human Health Assessment Scoping Document for Registration 

Review of Benzylchlorophenol and Salts (Case No. 2045). Memorandum from M. 

Centra, Pharmacologist to N.Mottl, Biologist. TXR No.: 1003210. June 22, 2011.

D310957. Quarantine Exemption for USDA/FSIS for Environ LpH to Control Prions in 

Slaughterhouses and Meat Processing Facilities. Memorandum from D. Smegal, MPH, 

Toxicologist/Risk Assessor to M. Wingfield. May 12, 2005. 

U.S.EPA (1987) Review of dose-ranging and main developmental toxicity studies in the 

rabbit and rat (Chlorophen©): Record nol 166294/166295: EPA ID No. 49403-

2/49403-3; Accession No. 258031: Proj. Nos. 1466/1467; Caswell # 83 

(Memorandum: J. Rowe to A. Castillo and O. Laird/PM #32, TXR# 005793, March 

27, 1987).

U.S.EPA (1988) Registrant rebuttal comments for 21-day dermal toxicity study with 

Chlorophen©; Record no. 2178886/2178887; EPA ID no. 49403-2/49403-3; Accession 

No. 259118; Proj. No. 8-0640; Caswell No. 83 (Memorandum: J. Rowe to J. Kempter 

(PM 32), TXR# 006690, May 5, 1988). 

U.S.EPA (1990) 49403-2. Chlorophen©: Review of registrant comments regarding a 

developmental toxicity study in the rabbit; Record No. 241099; EPA ID No. 49403-

2/49403-3; Project No. 9-1001; MRID No. 410039-01; Caswell No. 83. 

(Memorandum: J. Rowe to B. Pringle, PM Team #32, TXR# 008109, September 25, 

1990).

U.S.EPA (1990) 49403-2. Nipacide BCP. Antimicrobial Data Call-In. Submission of 

Data., Tox. Chem. No. 083, Project No. 0-1778. (Memorandum: P. Hurley to J. 

Wilson, PM Team #32, TXR# 008212, December 28, 1990). 

U.S.EPA (1991) Review two (2) mutagenicity studies with o-Benzyl Parachlorphenol 

(Nipacide). EPA Identifying No.: 49403-2, EPA MRID No.s: 412875-01 & 412875-

02, EPA Record No.: 255303, HED Project No. 0-0226, Caswell No. 83. 
Page 17 of 30 

(Memorandum: S. Dapson to J. Wilson/Kempter (PM 32), TXR# 008234, January 23, 

1991).

U.S.EPA (1994) 062202, 062203. Potassium and Sodium 2-Benzyl-4-Chlorophenate. 

Analogue Data for Toxicology Data Base. PC Codes 062202 and 062203, Tox. Chem. 

No. 083, Project Nos. D200190, D200423, Submission Nos. S459982, S460372 

(Memorandum: P. Hurley to E. Mitchel/PM Team #81, May 4, 1994). 

U.S.EPA (1995) o-Benzyl-p-chlorophenol Oualitative Risk Assessment Based on B6C3F1 

Mouse 2-Year Oral Gavage Study (Memorandum: L. Brunsman to P. Hurley, TXR# 

012759, February 23, 1995). 

U.S.EPA (1995) Toxicology Endpoint Selection Document, Chemical Name: o-Benzyl-pchlorophenol, TXR# 013105, (Committee Memorandum: P. Hurley and K. Baetke 

April 7, 1995). 

U.S.EPA (1995) ADDENDUM to o-Benzyl-p-chlorophenol. Changes in Data Evalutation 

Records and 1-Liners, PC Code 062201, Tox. Chem. No. 083, MRID Nos. 422793-01, 

00143775, 00145836, 00161231 (Memorandum: LP. Hurley to Caswell File, TXR# 

012758, April 18, 1995). 

U.S.EPA (1995) 062201. o-Benzyl-p-Chlorophenol Oualitative Risk Assessment Based 

on B6C3F1 Mouse 2-Year Oral Gavage Study (Memorandum: L. Brunsman to P. 

Hurley, TXR# 012758, April 11, 1995). 

U.S.EPA (1995) 062201. o-Benzyl-p-chlorophenol Draft Toxicology Chapter for the RED 

(Memorandum: P. Hurley to K. Boyle, May 17, 1995). 

U.S.EPA (1995) RfD/Peer Review Report of o-Benzyl-p-chlorophenol (Committee 

Memorandum: G. Ghali to R. Douglas, TXR# 011583, June 12, 1995). 

U.S.EPA (1995) 062201. o-Benzyl Para-Chlorophenol, The HED Chapter of the 

Reregistration Eligibility Decision Document (RED), Case 2045, Pesticide Chemical 

Code 062201, 062202 (potassium salt), 062203 (sodium salt) (Memorandum: K. Boyle 

to J. Kearns, TXR# 011631, August 4, 1995). 

U.S.EPA (1995) Carcinogenicity Peer Review of o-Benzyl-p-chloro-phenol (o-BCP) 

(Committee Memorandum: P. Hurley to R. Douglas, TXR# 011669, September 5, 

1995).

U.S.EPA (1995) Reregistration Eligibility Decision (RED) Ortho-Benzyl-P-Chlorophenol. 

EPA 738-F-96-027, December 1995. 

U.S.EPA (1995) R.E.D. FACTS, Ortho-Benzyl-P-Chlorophenol. PPTS (7508W). EPA 

738-F-96-027, December 1995. 
Page 18 of 30 

Toxicology Data Submissions 

MRID CITATION 

00130937 Cummins, H.; Gardner, J. (1983) Ortho-benzyl Parachlorophenol Acute 

Percutaneous Toxicity in the Rat: LSR Report No. 83/ BTP017/237. 

(Unpublished study received Aug 24, 1983 under 49403-2; prepared by 

Life Science Research, Eng., submitted by NIPA Laboratories, Inc., 

Wilmington, DE; CDL:251062-C).

00130938 Cummins, H.; Bannerman, M. (1983) Ortho-benzyl Parachlorophenol 

(Chlorophen): Acute Inhalation Toxicity in the Rat: LSR Report No. 

83/BTP030/296. (Unpublished study received Aug 24, 1983 un- der 49403-

2; prepared by Life Science Research, Eng., submitted by NIPA 

Laboratories, Inc., Wilmington, DE; CDL:251062-D). 

00131367 Cummins, H.; Gardner, J. (1983) Ortho-benzyl Parachlorophenol Acute 

Oral Toxicity in the Rat: LSR Report No. 83/BTP016/236. (Unpublished 

study received Aug 24, 1983 under 49403-2; prepared by Life Science 

Research, Eng., submitted by NIPA Laboratories, Inc., Wilmington, DE; 

CDL:251062-B). 

00131368 Cummins, H.; Gardner, J. (1983) Ortho-benzyl Parachlorophenol Acute 

Eye Irritation/Corrosion Test in Rabbits: LSR Report No. 83/BTP019/239. 

(Unpublished study received Aug 24, 1983 un- der 49403-2; prepared by 

Life Science Research, Eng., submitted by NIPA Laboratories, Inc., 

Wilmington, DE; CDL:251062-E). 

00131369 Cummins, H.; Gardner, J. (1983) Ortho-benzyl Parachlorophenol Acute 

Dermal Irritation/Corrosivity Test in Rabbits: LSR Report No. 

83/BTP018/238. (Unpublished study received Aug 24, 1983 under 49403-

2; prepared by Life Science Research, Eng., submitted by NIPA 

Laboratories, Inc., Wilmington, DE; CDL:251062-G). 

00143774 Ross, F. (1985) Chlorophen: Effects of Oral Administration upon 

Pregnancy in the Rabbit: Report Nos. 85/BTP033/161,85/BTP035/ 080. 

Unpublished study prepared by Life Science Research. 60 p. 

00143775 Willoughby, C. (1985) Chlorophen: Teratology Study in the Rat: Report 

Nos. 85/BTP032/054, 84/BTP031/583. Unpublished study pre- pared by 

Life Science Research. 82 p. 

00145836 Becker, H. (1984) Embryotoxicity (Including Teratogenicity) Study with 

Preventol BP Technical in the Rat: Project No. 035212. Unpublished study 

prepared by Research & Consulting Company. 101 p. 
Page 19 of 30 

00161231 Sachsse, K.; Becker, H. (1985) Letter sent to whom it may concern dated 

Oct 2, 1985: RCC Project 035212: Embryotoxicity (including 

teratogenicity) study with Preventol BP Technical in the rat: Date of report: 

November 27, 1984. Prepared by Research and Consulting Co. AG. 353 p. 

40376301 Birnbaum, L.; Deskin, R.; Grumbein, S.; et al. (1986) Prechronic toxicity 

of o-benzyl-p-chlorophenol in rats and mice. Fundamen- tal and Applied 

Toxicology 7:616-625. 

40988201 Ross, F. (1985) Chlorophen: Effects of Oral Administration upon 

Pregnancy in the Rabbit: Supplement to LSR Report No. 85/BTP033/ 161: 

LSR Report No. 85/BTP033/257. Unpublished study prepared by Life 

Science Research Limited. 67 p. 

41003901 Ross, F. (1989) Chlorophen--Effects of Oral Administration Upon 

Pregnancy in the Rabbit: Supplement to LSR Report No. 85/BTP003/ 257. 

Unpublished study prepared by Life Science Research Ltd. 19 p. 

41248201 Cummins, H. (1989) Product Toxicology: Nipacide BCP (Ortho-Benzyl 

Parachlorophenol): 21-Day Percutaneous Toxicity Study in the R Rabbit: 

Project ID NIPA-1989-4. Unpublished study prepared by Life Science 

Research Ltd. 195 p. 

41248202 Birnbaum, L. et al. (1986) Supplement to Prechronic Toxicity of OBenzyl-P-Chlorophenol in Rats and Mice: Project ID NIPA-1989-5. 

Unpublished study prepared by National Toxicology Program Batte- lle 

Columbus Division. 142 p. 

41287501 Mortelmans, K. (1989) National Toxicology Program Salmonella 

Mutagenicity Tests: II. Results from the Testing of 270 Chemicals 

Including Ortho-Benzyl Parachlorphenol: Lab Project Number: 

NIPA/1989/6. Unpublished study prepared by SRI International 40 p. 

41287502 Gulati, D. (1989) National Toxicology Program: In vitro Cytogenetic 

Testing of Ortho Benzyl Parachlorphenol: (Structural Chromosomal 

Aberration): Lab Project Number: NIPA/1989/7. Unpublished study 

prepared by Litton Bionetics, Inc. 10 p. 

41462401 Battelle (1990) Supplement No. 2: Prechronic Toxicity Study in Rats and 

Mice (O-Benzyl-p-chlorophenol): Lab Project Number: NIPA- 1990-1. 

Unpublished study. 159 p. 

41572801 Edwards, C. (1990) Nipacide BCP (Ortho-benzyl Parachlorophenol): 

Assessment of Clastogenic Action on Bone Marrow Erythrocytes in the 

Micronucleus Test: Lab Project Number: NIPA-1990-4. Unpublished study 

prepared by Life Science Research Ltd. 38 p. 
Page 20 of 30 

42279301 Hejtmancik, M.; Grumbein, S.; Athey, P.; et al. (1988) Final Report on the 

Chronic Gavage Study of o-Benzyl-p-Chlorophenol (CAS No. 120-32-) in 

Fischer 344 Rats to National Toxicology Program. Unpublished study 

prepared by Battelle. 161 p. 

42279302 Hejtmancik, M.; Ryan, M.; Grumbein, S.; et al. (1988) Final Report on the 

Chronic Gavage Study of o-Benzyl-p-Chlorophenol (CAS No. 120-32-1) in 

B6C3F1 Mice to National Toxicology Program. Unpublished study 

prepared by Battelle. 81 p. 

43313401 Warren, D. (1994) Dermal Absorption of (carbon 14)-o-Benzyl-pChlorophenol from a 5% Formulation: Lab Project Number: 94-722-XC: 

7332. Unpublished study prepared by Miles Inc. 60 p. 

45424201 Glaza, S. (2001) Dermal Sensitization Study in Guinea Pigs--Closed Patch 

Technique with Preventol BP: Final Report: Lab Project Number: 

01204836: 00C-I24-DC. Unpublished study prepared by Covance Labs., 

Inc. 63 p. {OPPTS 870.2600}. 

92007001 Eigenberg, D. (1990) Mobay Chemical Corp. Phase 3 Summary of MRID 

00145836 and Related MRIDs 00161231. Embryotoxicity (Including 

Teratogenicity) Study with Preventol BP Technical in the Rat: Project 

035212 (Mobay Report EHR 4099). Prepared by RCC, Research and 

Consulting Co. AG. 19 p. 

92008008 Dooley, T. (1990) Nipa Laboratories, Inc. Phase 3 Summary of MRID 

00131367. Ortho-benzyl Parachlorophenol (Chlorophen) Acute Oral 

Toxicity in the Rat. Prepared by Life Science Research 7 p. 

92008009 Dooley, T. (1990) Nipa Laboratories, Inc. Phase 3 Summary of MRID 

00130937. Ortho-benzyl Parachlorophenol (Chlorophen) Acute 

Percutaneous Toxicity in the Rat. Prepared by LIFE SCIENCE 

RESEARCH 7 p. 

92008010 Dooley, T. (1990) Nipa Laboratories, Inc. Phase 3 Summary of MRID 

00130938. Ortho-benzyl Parachlorophenol (Chlorophen) Acute Inhalation 

Toxicity in the Rat. Prepared by LIFE SCIENCE RESEARCH 9 p. 

92008011 Dooley, T. (1990) Nipa Laboratories, Inc. Phase 3 Summary of MRID 

00130939 and Related MRIDs 00013168. Ortho-benzyl Parachlorophenol 

(Chlorophen) Acute Eye Irritation/ Corrosion Test in Rabbits. Prepared by 

Life Science Research 7 p. 

92008012 Dooley, T. (1990) Nipa Laboratories, Inc. Phase 3 Summary of MRID 

00131369. Ortho-benzyl Parachlorophenol (Chlorophen) Acute Dermal 

Irritation Corrosive Test in Rabbits. Prepared by LIFE SCIENCE 

RESEARCH. 7 p. 
Page 21 of 30 

APPENDIX A: TOXICITY 

Guideline Numbers: Special Study

Study Titles: Dermal Sensitization Threshold Quantification 

Rationale for Requiring the Data

This study is needed to quantify the threshold for dermal sensitization based on the 

observation of a dermal sensitization response in the guideline dermal sensitization study 

(MRID 45424201) where OBPCP was found to be a sensitizer in guinea pigs. Severe 

dermal irritation and allergic type reactions in humans have also been reported in the 

available incident data bases following exposure to OBPCP, Na+OBPCP or K

+OBPCP. 

The symptoms included skin depigmentations, itching, pain, swelling, blister, hives, and 

erythema. Additionally, “Mice demonstrated statistically significant dose-dependent contact 

hypersensitivity responses to OBPCP with or without adjuvant pretreatment.” according to a 

published literature study by Stern, 1991. Therefore, the Agency is requiring a special study 

conducted with either OBPCP, Na+OBPC or K

+OBPCP that provides quantitative data and 

an assessment of dose-response for both the initiation and elicitation phases of skin 

sensitization. The purpose of this study is to identify a threshold level for quantification of 

dermal sensitization to OBPCP or its’ salts.

Practical Utility of the Data

1. How will the data be used?

The data would be used to identify a threshold for dermal sensitization of OBPCP or its’ 

salts. Specifically, these quantitative data would be used to identify a level (dose) of OBPCP 

or its’ salts that can then be used to establish a safe threshold to protect against dermal 

sensitization. 

2. How could the data impact the Agency’s future decision-making?

Currently, it is not possible to assess the residential dermal (repeat exposures) from 

textiles/clothing because the guideline dermal sensitization animal study does not provide 

dose-response data to establish an elicitation threshold level for sensitization. This study 

may provide results that change how risks are quantified. It is possible that a dermal 

sensitization toxicological endpoint may be established and the Agency may determine a 

level of safety based on the results of this study.

Guideline Number: 870.3465

Study Titles: 90-day Inhalation Toxicity Study

Rationale for Requiring the Data

The Agency is requiring a repeat-exposure inhalation toxicity study because 

occupational/residential and post-application/re-entry inhalation exposures to aerosols are 

expected to occur during mopping, wiping, spraying, trigger pump and particularly wet-mist 

fogging uses of OBPCP, Na+OBPC or K

+OBPCP. As a requirement under the proposed 40 

CFR 158 data requirements for toxicology, a 90-day inhalation toxicity study is required for 

registration review. The length of this study is adequate to assess risks from repeat 

inhalation exposures based upon the use patterns of products containing OBPCP, Na+OBPC

or K

+OBPCP.

This study is critical for pesticides with use patterns in which there is potential for repeated 

human exposures via inhalation. The design of an inhalation study simulates the route and 
Page 22 of 30 

duration of human exposure to aerosols of the test material. A detailed toxicological 

examination including the histopathology of the respiratory system would also be conducted 

in an inhalation toxicity study. The information from this study would better characterize 

potential toxicities from repeat inhalation exposures to OBPCP, Na+OBPC or K

+OBPCP

and may also provide a toxicity endpoint applicable to human health, inhalation risk 

assessment. 

Practical Utility of the Data

1. How will the data be used?

Although inhalation is a potential exposure route for several scenarios involving the use of 

OBPCP chemicals, there is no available repeat exposure inhalation toxicity study to 

demonstrate the types of adverse effects that may be manifested via this route of exposure or 

the dose(s) at which these respiratory-specific adverse effects occur. A dose and effect from 

a 90-day inhalation toxicity study are most appropriate for use as the hazard component in 

quantitative inhalation risk assessments. These data are critical to properly characterize and 

quantify the hazard and risks to occupational and residential applicators exposed to OBPCP, 

Na+OBPC or K

+OBPCP and may result in the identification of route specific and duration 

appropriate endpoints for risk assessment.

2. How could the data impact the Agency’s future decision-making?

In the absence of repeat inhalation toxicity data, the Agency is unable to estimate inhalation 

risks to persons applying products which contain OBPCP, Na+OBPC or K

+OBPCP. If used 

as the source of dose and effect for inhalation risk assessments, these new inhalation toxicity 

data would provide an estimate of the magnitude of this potential risk as well as providing a 

more complete characterization of overall mammalian toxicity and a better understanding of 

the effects of OBPCP or its’ salts on human health.

Guideline Number: 870.3800

Study Titles: Reproduction and Fertility Effects

Rationale for Requiring the Data

The difficulty of predicting real world human exposure via oral route with limited data and no 

reproductive toxicity data in rat or other alternative information, such as SAR, surrogate data, and/or 

weight of evidence to the Agency triggered the need for a reproductive (guideline) toxicity study in 

the rat, in order to adequately evaluate real work human exposure to OBPCP, Na+OBPCP or 

K

+OBPCP, particularly women (15-49 years of age), infants and children, based on how pesticide 

products containing these active ingredients are used.

Practical Utility of the Data

1. How will the data be used?

The data will allow the Agency to conclude more definitively whether or not there are any concerns 

for potential reproductive toxicity in the rat and it may also provide a toxicity endpoint applicable to 

risk assessment. Since the reproductive toxicity study will also include neurotoxicity evaluations, it 

will also provide some information regarding potential neurotoxicity in developing offspring 

exposed to OBPCP and salts.
Page 23 of 30 

2. How could the data impact the Agency’s future decision-making?

A reproduction and fertility effects study may result in a change in how risks are quantified for 

OBPCP, Na+OBPCP or K+OBPCP. The required study may provide a toxicity endpoint 

applicable to risk assessment. It is possible that the database uncertainty factor may be reduced or 

removed, resulting in a different magnitude of the value of the endpoint used for pesticide regulation.

Guideline Number: 870.7800

Study Titles: Immunotoxicity

Rationale for Requiring the Data

This is a new data requirement under 40 CFR Part 158 as a part of the data requirements for 

registration of a pesticide (food and non-food uses). 

The Immunotoxicity Test Guideline (OPPTS 870.7800) prescribes functional immunotoxicity testing 

and is designed to evaluate the potential of a repeated chemical exposure to produce adverse effects 

(i.e., suppression) on the immune system. Immunosuppression is a deficit in the ability of the 

immune system to respond to a challenge of bacterial or viral infections such as tuberculosis (TB), 

Severe Acquired Respiratory Syndrome (SARS), or neoplasia. Because the immune system is 

highly complex, studies not specifically conducted to assess immunotoxic endpoints are inadequate 

to characterize a pesticide’s potential immunotoxicity. While data from hematology, lymphoid 

organ weights, and histopathology in routine chronic or subchronic toxicity studies may offer useful 

information on potential immunotoxic effects, these endpoints alone are insufficient to predict 

immunotoxicity. Therefore, the Agency is requiring an immunotoxicity study conducted with either 

OBPCP, Na+OBPCP or K+OBPCP.

Practical Utility of the Data

1. How will the data be used?

Immunotoxicity studies provide critical scientific information needed to characterize potential hazard 

to the human population on the immune system from pesticide exposure. Since epidemiologic data 

on the effects of chemical exposures on immune parameters are limited and are inadequate to 

characterize a pesticide’s potential immunotoxicity in humans, animal studies are used as the most 

sensitive endpoint for risk assessment. These animal studies can be used to select endpoints and 

doses for use in risk assessment of all exposure scenarios and are considered a primary data source 

for reliable reference dose calculation. 

2. How could the data impact the Agency’s future decision-making?

If the immunotoxicity study conducted with OBPCP, Na+OBPCP or K+OBPCP shows that the 

test material poses either a greater or a diminished risk than that given in an earlier decision 

document conclusion, the risk assessments for the test material(s) may need to be revised to reflect 

the magnitude of potential risk derived from the new data. If the Agency does not have this data, a 

10x database uncertainty factor may be applied for conducting a risk assessment from the available 

studies.
Page 24 of 30 

APPENDIX B: HUMAN EXPOSURE 
Page 25 of 30 

Guideline Number: 875.1200 

Study Titles: Dermal Exposure (Indoor)

Rationale for Requiring the Data

Note: Dermal exposure data are needed for both residential and occupational uses. The selection 

of an outdoor versus an indoor site is based on the high end exposure scenario. In almost all 

cases, repeating an exposure study for the same scenario outdoors and indoors is not necessary.

The potential for dermal exposure is very likely for exposure scenarios involving wiping and 

spraying hard surface disinfectants. The existing CMA data base and PHED for these scenarios are 

limited in scope for QA/QC and number of monitoring units. EPA presented the need for 

additional handler exposure data to the January 2007 Science Advisory Panel (SAP) as well as to 

the April 2007 Human Studies Review Board (HSRB) and both groups agreed that additional data 

are warranted. 

The criteria for the dermal exposure data are based on the potential for dermal exposure from the 

labeled uses (e.g., occupational and residential exposures from spraying and wiping) and evidence 

of toxicity. If the toxicological endpoints from OBPCP and salts are used to assess the risks, there 

is an endpoint selected for the dermal route.

Practical Utility of the Data

1. How will the data be used?

The dermal exposure data will be used to assess dermal exposures from wiping and spraying 

disinfectants. For occupational uses, the dermal exposure data will be used to assess the short-, and 

intermediate- term exposures. The dermal exposure data will be used to determine the accuracy of 

the dermal risks to both residence and occupational workers.

2. How could the data impact the Agency’s future decision-making?

If risks warrant mitigation, the dermal exposure data will provide the types of mitigation necessary 

such as chemical resistant gloves or closed systems for commercial uses, or potential removal of 

uses from the label.

Guideline Number: 875.1400 

Study Titles: Inhalation Exposure (Indoor)

Rationale for Requiring the Data

Note: Inhalation exposure data are needed for both residential and occupational uses. The 

selection of an outdoor versus an indoor site is based on the high end exposure scenario (for 

inhalation the selection is typically indoors). In almost all cases, repeating an exposure study for 

the same scenario outdoors and indoors is not necessary.

The inhalation exposure route is very important for exposure scenarios such application of paints or 

metalworking fluids where aerosols would be generated. In addition, inhalation exposures from 

application are evident in exposure studies in the Pesticide Handlers Exposure Database (PHED). 

The significance of these exposures is directly affected by the severity of the inhalation 

toxicological endpoint of concern. At this point in time, no toxicological data are available to 

assess the inhalation risk. The existing Chemical Manufacturer Association (CMA) data base and 

PHED for these scenarios are limited in scope for QA/QC and number of monitoring units. EPA 

presented the need for additional handler exposure data to the January 2007 Science Advisory 

Panel (SAP) as well as to the April 2007 Human Studies Review Board (HSRB) and both groups 

agreed that additional data are warranted. 

The criteria for the inhalation exposure data are based on the potential for respiratory exposure 

from the labeled uses (e.g., exposure to disinfectants) and evidence of toxicity. If no toxicological 

endpoints of concern were identified, then the inhalation exposure data would not be needed.

Practical Utility of the Data
Page 26 of 30 

1. How will the data be used?

The inhalation exposure data would be used to assess the residential short-term duration of painting 

with a paint brush/roller and an airless sprayer. For occupational uses, the inhalation exposure data 

would be used to assess the short- and intermediate-term as well as pouring OBPCP. 

2. How could the data impact the Agency’s future decision-making?

If risks warrant mitigation, the inhalation exposure data will provide the types of mitigation 

necessary such as dust mist respirators, full face respirators or closed systems for commercial uses, 

or potential removal of uses from the label.

Guideline Number: 875.1600

Study Title: Data Reporting and Calculations 

Rationale for Requiring the Data

For all exposure studies this data need is needed to facilitate the review of the data.

The study report and all raw data/calculations would be reviewed for the adequacy of the 

data.

Practical Utility of the Data

1. How will the data be used?

The data are needed to interpret the dermal and inhalation exposure data collected.

2. How could the data impact the Agency’s future decision-making?

This data need is triggered if an exposure study is conducted. It would aid the Agency to 

make accurate interpretations of the studies to develop an accurate and refined risk 

assessment and refined mitigation.
Page 27 of 30 

Guideline Number: 875.1700

Study Title: Product Use Information

Rationale for Requiring the Data

Product use information is a description of how the product is actually applied; it is not 

afield study. A description of how this product is used would provide for a 

comprehensive realistic assessment of its potential applications. The description of the 

application techniques would be used to define the exposure scenarios to be assessed in 

the risk assessment.

Practical Utility of the Data

1. How will the data be used?

A complete description of product use would ensure that the risk assessment is inclusive 

of the types of exposures occurring during residential and occupational use.

2. How could the data impact the Agency’s future decision-making?

The need for a risk assessment as needed under Registration Review would require that 

the risk assessor understands how the product is applied.

Guideline Number: 875.2300

Study Title: Indoor Surface Residue Dissipation

Rationale for Requiring the Data

Based on the use of OBPCP as a hard surface disinfectant for countertops, human contact to 

treated countertops may occur. There are no data available to estimate exposure to adults and 

children from exposure to treated countertops, floors, carpets and clothing with OBPCP.

Practical Utility of the Data

1. How will the data be used?

Without data, the Agency will conduct a screening level assessment using a conservative surface 

residue value of 1 mg/cm2. Currently, there are no data that can be used to estimate exposure to 

adults or to children exposed to treated wood. These data will be used to refine the Agency’s risk 

assessment and to confirm or refute the Agency’s screening level assessment.

2. How could the data impact the Agency’s future decision-making?

Depending on the results of the dislodgeable residue study, the Agency may pursue risk mitigation 

measures regarding the use of formulated products containing OBPCP as the active ingredient in 

occupational and residential scenarios.

Guideline Number: 875.2500

Study Title: Inhalation Exposure

Rationale for Requiring the Data

The post application inhalation exposure may be required if it is determined that the use of 

these products have the potential to release OBPCP during the product use conditions 

(e.g., open systems, and vapor/mists from MWFs).

Practical Utility of the Data

1. How will the data be used?

The post application inhalation exposure data will be used to assess the residential and/or 
Page 28 of 30 

Guideline Number: 875.2800

Study Title: Descriptions of Human Activity

Rationale for Requiring the Data

Very limited worker activity data are available for antimicrobial pesticides, including material 

preservatives used in paint, and metal working fluids. Worker application parameters are generally 

defined by the physical nature of the formulation (e.g., formula and packaging), by the equipment 

required to deliver the chemical to the use site, and by the application rate required to achieve an 

efficacious dose. The risk assessment noted that many of the use parameters used (e.g., amount 

handled and duration of use) were based on professional judgments. These data are needed to fill this 

data gap and provide information needed to refine the risk assessment.

Practical Utility of the Data

1. How will the data be used? 

These data will clearly identify the specific equipment used to deliver OBPCP to the use site, which 

in high exposure scenarios, such a metal working fluids and paint applications, will allow the 

Agency to refine its risk assessment. 

2. How could the data impact the Agency’s future decision-making?

If review and evaluation of the descriptions of human activity data indicate that only closed-systems 

are used for mixing/loading and applying metal working fluids, then the need for a reproductivity

study is negated. Therefore, submission of acceptable human activity data demonstrating the metal 

working fluid scenario for OBPCP is an enclosed system will eliminate a significant cost and burden 

for the registrant (specifically, the costs associated with generating the reproductivity and fertility 

study data). For the other use scenarios, descriptions of human activity data will allow the Agency to 

refine its risk assessment and make decisions using fewer assumptions and more reliable data. 

occupational inhalation risks to estimate reentry exposure to fogging from a thermal fogger

product use. This data is needed to conduct an inhalation postapplication assessment

2. How could the data impact the Agency’s future decision-making?

The inhalation exposure data will be used to determine the accuracy of the post 

application inhalation risks to occupational bystanders. If risks warrant mitigation, the 

inhalation exposure data will provide the types of mitigation necessary such as respiratory 

protection from respirators or closed systems for commercial uses to potential removal of 

uses from the label.
Page 29 of 30 

Guideline Number: 875.2900 

Data Requirement: Data Reporting and Calculations

Rationale for Requiring the Data

For all exposure studies, these data are needed occupationally and in the residential setting to 

facilitate the review of the data. 

Practical Utility of the Data

1. How will the data be used? 

The study report and all raw data/calculations will be reviewed for the adequacy of the data. 

2. How could the data impact the Agency’s future decision-making?

The data are needed to define and interpret the inhalation and dermal exposure data collected. 

This data need is triggered any time an exposure study is conducted. It would aid the Agency to 

make accurate interpretations of the studies to develop an accurate and refined risk 

assessment and refined mitigation.

Guideline Number: 875.3000 

Data Requirement: Non-Dietary Ingestion

Rationale for Requiring the Data

The design of the non dietary ingestion exposure study can be combined with the Indoor 

Surface Residue Dissipation study (875.2300) to determine the available residue leaching 

from hand-to-mouth behavior on counter tops treated with OBPCP disinfectant.

Practical Utility of the Data

1. How will the data be used? 

This product is used as a disinfectant on counter tops. The available residues from hard 

surfaces will be used to determine the magnitude of children’s incidental exposure from 

these uses.

2. How could the data impact the Agency’s future decision-making?

The data are needed to refine the risk estimates if risks of concern are identified assuming 

100% residue transfer from contact from hard surfaces (e.g., counter tops). 

If risks of concern are not identified when 100% residue transfer is assumed, the data are 

not needed.
Page 30 of 30 

APPENDIX C: REGISTRATIONS 

I- PC Code 062201, 2-Benzyl-4-chlorophenol

Current Active Products for AI:

211-62 1043-118 5741-22 39967-81 

303-223 1677-128 6836-252 39967-83 

303-225 2212-17 6836-253 46851-1 

675-19 2296-102 33176-6 46851-5 

675-43 2296-105 34810-8 46851-10 

777-94 3862-177 34810-21 61282-53 

954-13 3862-178 34810-31 62296-1 

1043-19 3862-179 39967-5 66171-1 

1043-26 3862-180 39967-6 66171-2 

 70385-7 

 70627-6 

II- PC Code 062202, Potassium 2-benzyl-4-chlorophenate

Current Active Products for AI:

211-25 4313-41 74655-24

III- PC Code 062203, 2-Benzyl-4-chlorophenol, sodium salt

Current Active Products for AI:

211-36 1769-374 3862-11

Sign-off Date : 06/22/11 

DP Barcode Nos.: D383100 and D389630