Polybutene Human Health Risk Assessment DP No. D392729

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1.0 Executive Summary

The Pesticide Re-evaluation Division has requested that the Health Effects Division (HED) 

perform an assessment of human health risk to support the registration review of polybutene. 

Polybutene is a viscous, non-drying polymeric liquid that is registered as a repellent to prevent

birds from roosting on the inside or outside of buildings. Product formulations are available as a 

gel for outdoor application to buildings or other structures using a caulking gun or putty knife 

and a liquid for application to indoor structures using a low-pressure spray gun or paint brush. 

The liquid product is also used to repel beavers from gnawing on and damaging the trunks of 

trees and shrubs. It is not toxic to the target species, but discourages contact by creating an 

unpleasant, sticky surface. There are no registered food/feed uses and existing use patterns are 

not expected to contaminate surface or ground water; a dietary exposure assessment was 

therefore not required. Polybutene is exempt from the requirement of a tolerance when used as a 

sticker agent in packaging of insect control products used on food crops.

Polybutene is approved by the Food and Drug Administration (FDA) as an indirect food additive 

and is used as an ingredient in cosmetic products that are applied directly to the skin such as sun 

block or moisturizer, and that may be incidentally ingested, such as lipstick. Concentrations of 

polybutene in cosmetic products may range from 1% to 50%. The use of polybutene in cosmetic 

products is considered safe, according to a review of available toxicity information by the 

Cosmetics Industry Review (CIR) Scientific Panel report. The report was taken into 

consideration in this assessment.

The toxicological database is considered adequate for characterizing hazard and assessing risk 

from polybutene. No additional studies were requested during registration review scoping. 

Most oral studies show no toxicity at the limit dose, although in a rat two-year dietary study, 

possible treatment-related mortality in males (but not females) was observed in the absence of 

other effects. Dermal toxicity is not anticipated based on the lack of oral toxicity. Acute 

lethality studies indicate low oral and dermal toxicity. Polybutene is not a dermal irritant, 

although moderate primary eye irritation was observed with the technical product. An acute 

inhalation study was waived due to the viscosity of the test substance. A published two-week 

inhalation study in the male rat was conducted using polybutene vapor. Mortality, and 

pulmonary edema and hyperemia in the rats that died, were observed at the higher of two dose 

levels; however, this endpoint was not considered appropriate for selecting an inhalation 

exposure endpoint for human health risk assessment. A dose-response could not be determined 

and the effects likely resulted from direct lung effects due to the viscous nature of the test 

substance at a high concentration that is not relevant to the low level of human inhalation 

exposure expected from application of polybutene products. Based on these findings and the 

conclusions of the CIR panel report, no toxicological endpoints of concern were identified for 

dermal or inhalation exposure to polybutene.

A number of studies required under the revised 40 CFR Part 158 guidelines, including 

immunotoxicity and neurotoxicity, were not submitted. However, based on a consideration of 

the available information on polybutene toxicity, including the safety of polybutene as a food 

additive and cosmetic ingredient, additional studies are not expected to identify effects of 

concern. An inhalation study is not required, based on the minimal potential for inhalation 
Polybutene Human Health Risk Assessment DP No. D392729

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exposure due to the type of application, and the limited use of the products, particularly the 

liquid formulation, as determined from recent annual usage information.

The registered end-use products of polybutene are intended for professional and commercial 

application, but there are no restrictions for homeowner use. Therefore, both residential and 

occupational applicator and post-application exposures were considered in this assessment. 

Dermal exposure may occur from application of polybutene gel and liquid products; inhalation 

exposure may result from spray application of the liquid formulation. 

Although exposure may occur during application of these products, quantitative exposure 

assessments were not performed for polybutene. Dermal or inhalation endpoints of concern were 

not identified. Dermal toxicity is not anticipated based on lack of oral effects and the 

expectation of low absorption due to the relatively large size of polybutene molecules. 

Inhalation toxicity is of low concern due to the expectation of limited exposure via this route. 

Furthermore, exposure from use of the liquid formulation product, which is applied via a lowpressure spray, is limited. The product is applied to a limited physical area on an intermittent 

basis and represents a low level of usage, based on recent information on lbs. sold per year 

(personal communication, Joel Wolf, PRD; 2012).

Post-application residential exposure is not of concern because no contact is expected with 

treated surfaces and due to the non-volatile properties of the formulations. Post-application 

occupational exposure is not anticipated based on the current use patterns.

2.0 HED Recommendations

Sufficient data are available to support the human health risk assessment of polybutene. No 

changes to current product labels are needed.

3.0 Introduction

Polybutene is a viscous, sticky, non-drying polymeric substance with an average molecular 

weight of 320 to 420 or higher. Currently registered uses are limited to surface applications on 

indoor and outdoor sites (structures, trees or shrubs) as a repellent to prevent (1) birds such as 

starlings or pigeons from roosting in unwanted structures or trees/shrubs and to prevent (2) 

beavers from gnawing on and damaging trunks of trees and shrubs. Polybutene is not toxic to 

these species; rather, it acts as a repellent because they find the sticky surface unpleasant. There 

are no registered food/feed uses. There is an exemption from the requirement of a tolerance for 

polybutene when it is incorporated into the packaging of insect control products used on food 

crops. 

There are also numerous other uses of polybutene. It is a common ingredient in cosmetic 

products, including lipstick, eye makeup, sunscreen and moisturizers, at concentrations ranging 

from 1% to 50% (w/w). The Food and Drug Administration (FDA) approved polybutene as an 

indirect food additive for use in packaging that may come into contact with food (§177.1430 of 

the 21 CFR, the Food Additive Regulation of FDA). Other uses include as a lubricating-oil 
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additive, polymer modifier and to increase viscosity or tackiness in products such as cable 

insulators, adhesives, special sealants, films and coatings.

3.1 Chemical Identity

The chemical identity and chemical structure for polybutene is shown below in Table 3.1.

Table 3.1 Test Compound Nomenclature

Chemical Structure

See empirical formula – polymeric structure of varying size

Empirical Formula R3 C-[C4 H8 ]n -CH=CR2 , where R=CH 3

Common Name Polybutene

Company experimental name NA

CAS Name 1-butene polymer

CAS Registry Number 9003-29-6

End-use product/EP Tanglefoot Bird Repellent; 4 the Birds Repellent; Hot Foot Bird Repellent

Chemical Class Trisubstituted olefin

Known Impurities of Concern None

3.2 Physical/Chemical Characteristics

Polybutene is a polymer of isobutene and n-butene with an average molecular weight of 320-

420. It is a light-colored, viscous liquid that is non-drying and sticky: the viscosity is 

proportional to its polymeric molecular weight. It is stable to light and is not reactive. Although 

it may soften in heat, once the product is set it does not liquefy and run at temperatures likely to 

be encountered in the outdoor or indoor environment. Polybutene is insoluble in water, and has a 

specific gravity of 0.89 g/mL at 37°C. The boiling point is 160°C and the vapor pressure is 0.13

mm Hg at 25°C.

3.3 Pesticide Use Pattern

The registered product formulations containing polybutene are listed in Table 3.3.1. There is no 

registration on a technical product and the four active registrations are end-use product (EP) 

formulations. Three of the four EPs are formulated as gels and packaged in ready-to-use tubes 

and the fourth is a liquid. 

Table 3.3.1. Registered Products of Polybutene.

 EPA Reg. No. AI % Formulation Type Product's Name 

1621-17 97.0 Gel Tangle foot Bird Repellent

8254-3 49.0 Liquid 4 The Birds, Transparent Bird Repellent Liquid
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Table 3.3.1. Registered Products of Polybutene.

 EPA Reg. No. AI % Formulation Type Product's Name 

8254-5 93.0 Gel 4 The Birds, Bird Repellent

55943-1 93.5 Gel Hot Foot Bird Repellent

Polybutene formulations are registered to repel birds such as pigeons, starlings and sparrows 

from roosting inside and outside of homes and structures, and beavers from damaging trees and 

shrubs. The use pattern for registered products is summarized in Table 3.3.2. 

Table 3.3.2. Use Pattern of End-use Product Formulations of Polybutene.

EPA Reg. No. 

And Name. Appl. Sites Appl. Equipment and rate Comments

1624-17, (97% ai)

Bird Repellent 

8254-5, (93% ai), 

4 The Birds Bird Repellent

55946-1, (93.5% ai)

Hot foot Bird Repellent 

Outdoor: on 

buildings and other 

exterior structures

Caulking gun or a putty 

knife @ 1 oz product per 

linear ft.

To reduce exposure to bird 

related diseases, wearing 

water proof gloves and a 

respirator (approved for 

dust) is recommended for 

cleaning the areas before 

treatment.

8254-3 (49% ai)

4 The Birds Transparent 

Bird Repellent

Interior: buildings 

Exterior: trees and 

shrubs 

Spray to the point of run-off 

using a low-pressure spray 

gun or use a paint brush to 

treat surfaces that are 

difficult to spray.

Do not dilute before 

spraying. Do not apply to 

exterior of buildings and 

structures. Do not apply 

using aerial equipment.

The treated sites include window sills, cornices, roof lines, gutter edges, signs, ledges, bridges, 

overpasses, beams, girders, struts, and supports where birds can sit and roost. Exterior sites are 

trees, bushes and vines adjacent to buildings and structures. 

The gel formulations are applied in bands, two inches apart for the length of the area in broken 

strips, leaving a one inch gap between beads to allow drainage of water. A putty knife can also 

be used to apply the gel. The recommended application rate is approximately 1 oz. of product 

per linear foot. Repeat applications may be made if the applied gel is flattened with time or 

covered with dirt and debris due to heavy bird traffic.

 

The liquid product is either sprayed with a low pressure handgun or applied using a paint brush 

to the surface of beams and rafters (indoors) or around the trunks of trees and bushes (outdoors). 

In outdoor areas, repeat applications may be made at 2-3 week intervals when the applied area 

has a weathered appearance. For indoor areas, no repeat applications have been recommended. 

Table 3.2.3 summarizes the total products (pounds ai) sold in 2011 for each registration number

(Joel Wolf, BEAD, personal communication; 2012). Polybutene products represent a fairly 

limited use. Of the liquid formulations, the “4 the Birds” formulation has the lowest annual use 

rate (<6000 lbs.).
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Table 3.2.3. Pounds of Polybutene Sold in 2011 by Product Registration

EPA Registration No. Product Name % AI Lbs. AI Sold in 2011

8254-3 4 the Birds Transparent Bird Repellent Liquid 49 5,954

8254-5 4 the Birds Bird Repellent 93 29,993

55943-1 Hot Foot Bird Repellent 93.5 4,353

1621-17 Tanglefoot Bird Repellent 97 48,736

3.4 Anticipated Exposure Pathways

Based on the currently registered uses, humans could be exposed to polybutene through 

professional and homeowner application of products. Exposure via the dermal and inhalation 

routes is possible. Occupational and residential post-application exposure (dermal, inhalation, 

incidental oral) are considered unlikely due to the nature of the applications. Dietary exposure 

from the currently registered uses of polybutene is not anticipated. There are no food/feed uses 

and contamination of ground or surface water is not anticipated from existing use patterns due to 

the nature of the applications and the minimal overall use of the product. 

Polybutene is also a commonly used ingredient in many cosmetics. Humans may be exposed 

through use of cosmetic products, such as lipstick, eye makeup, moisturizers and sun block, 

containing polybutene at concentrations ranging up to 50% (w/w).

3.5 Consideration of Environmental Justice

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

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.doe.gov/oepa/guidance/justice/eo12898.pdf. As a part of every pesticide risk 

assessment, the Office of Pesticide Programs (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 Intake by Individuals (CSFII) 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. Whenever 

appropriate, non-dietary exposures based on home use of pesticide products and associated risks 

for adult applicators and for toddlers, youths, and adults entering or playing on treated areas 

post-application are evaluated. Further considerations are currently in development as OPP has 

committed resources and expertise to the development of specialized software and models that 

consider exposure to bystanders and farm workers as well as lifestyle and traditional dietary 

patterns among specific subgroups.
Polybutene Human Health Risk Assessment DP No. D392729

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4.0 Hazard Characterization and Dose-Response Assessment

4.1 Toxicology Studies Available for Analysis

The toxicity of polybutene was reviewed for the RED document (December, 1994). All 

toxicology studies, except for acute toxicity and genotoxicity, were waived in that assessment, 

based on lack of effects observed in the available studies and the expectation of minimal 

exposure from registered uses (Appendix A.1, Toxicology Data Requirements). Additional 

toxicity data were reviewed (as brief summaries) subsequent to the RED, for a proposed 

amended tolerance exemption as an inert ingredient (see Appendix A.2, Tables A.2.1 and A.2.2, 

for a profile of the studies reviewed by the Agency). Studies reviewed by the Agency include 

acute toxicity (with the exception of acute inhalation, which was waived based on the viscous 

nature of the test substance), genotoxicity studies and a subchronic dietary study in the rat. A 

published two-week inhalation toxicity study (non-guideline) was also reviewed. The Agency 

also considered the Final Report on the Safety Assessment of Polybutene (1982) by the Cosmetic 

Ingredient Review (CIR) Scientific Panel, which evaluated the toxicity of polybutene for use in 

cosmetic products from available toxicological studies. CIR is an industry trade organization 

that sponsors review of cosmetic ingredient safety by panels of expert scientists. The Scientific

Panel evaluated the available toxicological data on polybutene, including the subchronic oral and 

inhalation studies reviewed by the Agency, as well as numerous other studies in test animals. 

Animal studies included chronic (two-year) dietary studies in the rat and dog, reproductive and 

developmental studies in the rat and numerous acute studies. 

Although a complete toxicological database based on current 40 CFR Part 158 guidelines has not 

been submitted, the available toxicological data for polybutene are considered adequate for 

assessment of human health risk due to its low toxicity and the limited use of products containing 

polybutene. No additional studies are required at this time. Additional toxicology data were not 

required during registration review scoping.

4.2 Toxicological Effects

In addition to the acute, genotoxicity, subchronic rat and two-week rat inhalation toxicity studies 

reviewed by the Agency, the conclusions of the Final Report on the Safety Assessment of 

Polybutene by the CIR Expert Scientific Panel in 1982 (reaffirmed again in 2002) were 

considered in evaluating the toxicity of polybutene. Based on their review, the panel determined 

that polybutenes are “relatively harmless” and “safe as presently used in cosmetics.” 

No target organs were identified following oral exposure to polybutene. In a 90-day dietary 

study in the rat, no toxicity in male or female rats (body weight changes, hematological and 

limited clinical chemistry parameters, organ weights and histopathology) was noted at 2500 

mg/kg/day, the only dose tested. Several oral studies, including subchronic rat, chronic dog, rat 

reproduction and developmental toxicity studies did not identify toxic doses at or above the limit 

dose (the rat reproductive toxicity and chronic two-year oral studies in the rat and dog were not 

considered acceptable by the Agency at the time of submission because the integrity of the data 

was not validated). Rats fed polybutene for two years (30/sex/dose) at 0, 200, 4000 or 20,000 

ppm showed no effects except for a possible treatment-related mortality in males at the limit 
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dose of 20,000 ppm: six high-dose males died between weeks 17-24 (three with reported 

hematuria), but no other findings were reported and no toxicity was observed in females. There 

was no evidence of carcinogenicity. A published study evaluating developmental toxicity 

reported that no effects were observed after six months’ administration of polybutene at 1% or 

10% in the diet (1968) but details were not available for review. 

No dermal absorption or toxicity data are available, but based on lack of toxicity in the oral

studies, no toxicity from exposure via the dermal route is anticipated. In addition, as a polymeric 

compound of average molecular weight exceeding 300, absorption is expected to be low. 

The lungs are a target organ with inhalation exposure at higher ambient concentrations. In a 

published two-week inhalation study, mortality was observed in male Wistar rats exposed to 

polybutene aerosol (7 hrs/day, 5 days/week). Females were not tested. At 700 mg/m

3

, death 

occurred in one of six animals during the first day of exposure and two additional males on the 

sixth day of exposure (study Day 8). Pulmonary edema and hyperemia were also observed in 

these animals, suggesting that the test material may have had local toxicity to the lung. These 

effects are likely due to the viscous properties of polybutene at a relatively high ambient 

concentration and would not occur at exposure levels resulting from current uses of polybutene 

products. No effects were seen at 70 mg/m3, but intermediate doses were not evaluated and a 

dose-response could therefore not be evaluated. Additional inhalation data was not required, 

since inhalation exposure is expected to be minimal and use of the liquid spray product is 

limited. As noted below, two acute inhalation studies identified by the CIR panel showed low 

toxicity.

Polybutene was negative for genotoxicity in the Salmonella typhimurium reverse gene mutation, 

Chinese Hamster Ovary (CHO) cell mammalian forward gene mutation and in vivo mouse bone 

marrow micronucleus assays. Test material purity information on the bacterial reverse gene 

mutation assay was required at the time of review to upgrade it to "acceptable." However, based 

on the lack of concern for genotoxicity, no additional information is required at this time.

Although immunotoxicity and neurotoxicity studies are not available, the available information

indicates that polybutene would not be expected to affect either the immune or nervous systems, 

particularly at the low exposure levels expected with the use of registered products. These 

studies are therefore not required; furthermore, as there are no endpoints identified for risk 

assessment, a 10x database uncertainty factor is not applied. 

Polybutene is of low acute toxicity by the oral and dermal exposure routes (Category IV and III, 

respectively). An acute inhalation toxicity study was waived based on the viscosity of the test 

material. However, it is noted that the CIR report identified two acute inhalation studies: in 

contrast to the published two-week inhalation study, no toxicity was observed in rats exposed for 

4 hour exposures to 17 or 18 mg/L (Toxicity Category III). It is not a dermal irritant or 

sensitizer, but in one study was moderately irritating to the eye (Category II). Other primary eye 

studies showed low or no irritation.
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4.3 Dose-Response Assessment

A dose-response assessment was not performed for polybutene. No toxicity endpoints or points 

of departure were identified. In oral toxicity studies, no toxicological effects were reported, with 

the exception of possible treatment-related mortality in males at the limit dose (20,000 ppm or 

approximately 1000 mg/kg/day) in the two-year rat study. No effects were seen in males at 4000 

ppm or in females at any dose, nor was toxicity observed at 2500 mg/kg/day in a 90-day rat 

feeding study. In a published two-week inhalation study in the rat, mortality and pulmonary 

edema/hyperemia in 3/6 animals and increased lung weight were reported at the high dose of 700 

mg/m3, but only one other dose level at a ten-fold lower concentration (70 mg/m3) was tested. 

The study was also limited by the small number of animals (6 males per group). Based on the 

viscous nature of polybutene, these effects appear to result from a direct effect to the respiratory 

tract (e.g., coating of alveoli, clogging of airways) and are likely to be more pronounced in the 

smaller airways of the rat than in humans. Such effects are not expected to occur at exposure 

levels that might be encountered from current uses of polybutene and are therefore not 

considered relevant to human health risk assessment. 

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

An FQPA safety factor assessment was not performed because there are no food uses for 

polybutene.

5.0 Water Residue Profile

Based on the existing use patterns, contamination of surface or ground water from outdoor use is 

not anticipated. Use of this product is limited. Polybutene is a sticky, water-insoluble substance 

that remains on the surface of the treated area. An assessment of drinking water exposure was 

therefore not performed.

6.0 Residential (Non-Occupational) Exposure/Risk Characterization

6.1 Residential Handler Exposure

Although all products are labeled for use by commercial and professional applicators, there are 

no restrictions on homeowner use and therefore residential applicator/handler dermal and 

inhalation exposure was considered in this assessment. Dermal exposure may occur from use of 

the gel or liquid products; inhalation exposure may also occur from spray application of the 

liquid product. Inhalation exposure from the gel formulation is not of concern due to the use 

pattern and application method (paintbrush and caulking gun). The products are not highly 

volatile.

The toxicity studies on end-use products indicate that they have moderate acute toxicity and were 

assigned Signal Words such as CAUTION to WARNING. No personal protective equipment 

(PPE) is required on the labels for these products because polybutene formulations are used at 

sites exempted from the requirement for Worker Protection Standard (WPS) language on the 

label.
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A quantitative assessment of residential handler exposure was not performed, based on 

consideration of several factors. No endpoints of concern were identified for polybutene from 

oral studies. An endpoint for dermal toxicity was not selected based on lack of oral toxicity. In 

addition, low dermal absorption of polybutene would be predicted due to its large size. An 

endpoint appropriate for inhalation exposure to humans was also not identified. Inhalation 

exposure from use of the liquid spray is expected to be minimal based on the use pattern 

(application is to a limited physical area and likely to be done on a sporadic basis). Additionally, 

based on pounds sold per year (less than 6000 lbs. in 2011), there is limited usage of this 

product. 

6.2 Residential Post-Application Exposure

Residential post-application dermal exposure to adults and children from gel and liquid 

formulations is expected to be negligible because of the lack of contact with the treated surfaces, 

both inside and outside of structures; application inside homes does not occur, in accordance 

with the use pattern. Inhalation exposure to occupants of indoor areas treated with the liquid 

product is not of concern because polybutene is not highly volatile. There is no likelihood of 

children's post-application incidental oral exposure from indoor uses as the treated areas are not 

accessible. Due to the sticky nature of polybutene, flakes that could be ingested by children do 

not form and fall to the ground.

7.0 Occupational Exposure/Risk Characterization

7.1 Occupational Handler Exposure

Occupational dermal and inhalation exposure may occur from current uses of polybutene. A 

quantitative assessment of occupational handler exposure was not performed – see Section 6.1 

for rationale.

7.2 Occupational Post-Application Risk

Based on current use patterns of polybutene products, no post-application activities are expected 

to be performed in treated interior or exterior areas. Therefore, an occupational post-application 

exposure assessment was not performed.

8.0 References

Bradley, M. J. Inert Ingredients: Polyvinyl chloride, Butylbenzyl phthalate, and Polybutenes. 

Addition to Request of 6/24/81, August 12, 1982.

Bradley, M. J. Inert Ingredients: Polyvinyl chloride, Butylbenzyl phthalate, and Polybutenes on 

Artichokes. Additional Information to Request of 6/24/81, November 26, 1982.

Cosmetic Ingredient Review (1982) Final Report on the Safety Assessment of Polybutene. J. 

Am. Coll. Toxicol. 1(4):103-118.
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Cosmetic Ingredient Review: Final Report on the Safety Assessment of Polybutene. J. Am. Coll. 

Toxicol. 1(4):103-118, 1982.

Davis, D. S., D194367. PP# 3E4254: Polybutene: Request for Clearance as an Inert Ingredient 

under 40CFR§180.1001(c) an (e). November 24, 1993.

Jones, R. Structure Activity Team (SAT) Report for Polybutene. October 20, 1995.

Liem, D.S., D194369, D214154. Review of Toxicological Data Package on Polybutene in 

Support for a Tolerance Exemption Under 40 CFR 180.1001© and (e) (Inert). April 21, 1995. 

Liem, D.S., D216536, D217639. Review of a Toxicological Data Rebuttal and Additional Data 

on Polybutene in Support for an Amended Tolerance Exemption Under 40 CFR 180.1001(d) 

(Inert). November 1, 1995. 

Liem, D. S., D223859. Review of a Proposal on a Selection of Polybutene Grade for a 

Subchronic Feeding and a Developmental Study (Inert). April, 26, 1996.

Oonnithan, S. and Hansen, L., D371748. Polybutene: Human Health Assessment Scoping 

Document in Support of Registration Review. April 23, 2010.

Ritter, D. Inert Ingredients for Use in an Insect Pheromone dispenser in Artichokes. EPA File 

Symbol: #8730-EUP-RR. October 13, 1981.

Ritter, D. Request to Broaden Exemption as an Inert Ingredient in all RACs, November 24, 

1981.

Schmidt, R. P., Polyvis OSH – Inert Ingredient Used in Proturf Systemic Fungicide, January 8, 

1974.

US EPA. The HED Chapter of the Reregistration Eligibility Decision Document (RED) for 

Polybutene. Memo from M. Clock to J Ellenberger, December 7, 1994. HED Doc. No. 011351.

US EPA: Reregistration Eligibility Decision (RED) – Polybutene. 

http://www.epa.gov/oppsrrd1/REDs/4076, 1994.

US EPA. EPA RED Facts: Polybutene, January, 1995.

Winfield, S., D372034. Polybutene Resins: Review of Human Incidents, February 25, 2010.

Woodrow, W. S. Amendments to EPA # 36638-EUP-G, PP # 9G2226, Heliothis virescens

(tobacco budworm) Mating Disruptant Pheromone Used on Cotton, June 5, 1981.
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Appendix A. Toxicology Profile and Executive Summaries

A.1 Toxicology Data Requirements

The requirements (40 CFR 158.340) for non food use for polybutene are in Table 1. Use of the new guideline 

numbers does not imply that the new (1998) guideline protocols were used.

Study

Technical Polybutene

Required Satisfied

870.1100 Acute Oral Toxicity.......................................................

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

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

870.2400 Primary Eye Irritation....................................................

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

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

yes

yes

no

yes

yes

yes

yes

yes

-

yes

yes

yes

870.3100 Oral Subchronic (rodent)...............................................

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

870.3200 21-Day Dermal ..............................................................

870.3250 90-Day Dermal ..............................................................

870.3465 90-Day Inhalation..........................................................

yes 

no

no

no

no

yes 

-

-

-

-

870.3700a Developmental Toxicity (rodent)...................................

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

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

no

no

no

-

-

-

870.4100a Chronic Toxicity (rodent) ..............................................

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

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

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

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

no

no

no

no

no

-

-

-

-

-

870.5100 Mutagenicity—Gene Mutation - bacterial.....................

870.5300 Mutagenicity—Gene Mutation - mammalian................

870.5xxx Mutagenicity—Structural Chromosomal Aberrations...

870.5xxx Mutagenicity—Other Genotoxic Effects.......................

yes1

yes

yes

no

yes

yes

yes

-

870.6100a Acute Delayed Neurotoxicity (hen)...............................

870.6100b 90-Day Neurotoxicity (hen)...........................................

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

870.6200b 90-Day Neurotoxicity Screening Battery (rat)...............

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

no

no

no

no

no

-

-

-

-

-

870.7485 General Metabolism ......................................................

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

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

no

no

no

-

-

-

Special Studies for Ocular Effects

Acute Oral (rat)...........................................................

Subchronic Oral (rat) ..................................................

Six-month Oral (dog)..................................................

no

no

no

-

-

-

1 Test material purity information not submitted but study accepted based on general lack of effects and negative 

results in other genotoxicity studies.
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A.2 Toxicity Profiles for Polybutene

Table A.2.1. Acute Toxicity Profile - Polybutene Technical.

Guideline No. Study Type MRID(s) Results Toxicity Category

870.1100 Acute oral-rat 41772401 LD50 >5.0 g/kg IV

870.1200 Acute dermal-rabbit 41772402 LD50 >2.0 g/kg III

870.1300 Acute inhalation-rat 1-- -- N/A1

870.2400 Acute eye irritation-rabbit 41772403 Eye irritant II

870.2500 Acute dermal irritation-rabbit 41772404 Not a dermal 

irritant

IV

870.2600 Skin sensitization-guinea pig 41772405 Not a sensitizer N/A

1.

 The acute inhalation study was waived based on viscosity of test material.
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Table A.2.2. Subchronic, Chronic and Other Toxicity Profile for Polybutene.

Guideline 

No. 

Study Type MRID No. (year)/ 

Classification /Doses

Results

870.3100 90-Day oral toxicity (diet) 

- rat

00117945 (1982)

Acceptable/non-guideline

2500 mg/kg/day, administered 

in diet 

NOAEL = 2500 mg/kg/day

LOAEL = not determined (>2500 

mg/kg/day) 

870.3150 90-Day oral toxicity - dog Not available.

870.3200 21-Day dermal toxicity Not available.

Nonguideline -

inhalation

2-week inhalation toxicity -

rat

Published article, Skyberg et al.

(1990) Env. Res. 53:48-61.

Acceptability not determined

Whole-body aerosol inhalation 

exposure of 6 male rats/dose 

group for 7 hrs/day, 5 

days/week for two weeks at 70 

or 700 mg/m3

NOAEL = 70 mg/m3

LOAEL = 700 mg/m3, based on 

pulmonary edema and hyperemia, 

and mortality (exposure days 1 and 

6).

870.3700a Prenatal developmental-rat Not available.

870.3700b Prenatal developmental -

rabbit

Not available.

870.3800 Reproduction and fertility 

effects-rat

Not available.

870.4100a Chronic toxicity-rodent Not available.

870.4100b Chronic toxicity-dog Not available.

870.4200b Carcinogenicity (mouse) Not available.

870.4300 Combined chronic 

toxicity/carcinogenicity-rat

Not available.

870.5100 Bacterial Reverse Gene 

Mutation Assay

(S. typhimurium strains 

TA97a, TA98, TA100, 

TA102 or TA1535) 

43076602 (1993)

Acceptable/guideline ( analysis 

confirming test material 

concentration not submitted but 

not required based on lack of 

genotoxicity in other studies 

and general lack of toxicity)

0.08, 0.1, 0.33, 0.8, 1.0, 3.3 or 

5.0 mg/plate, tested with and 

without S9 activation 

NEGATIVE

No evidence of induced mutant 

colonies above background in S. 

typhimurium in the presence or 

absence of S9 activation. Tested up 

to limit dose (no cytotoxicity or 

precipitation observed).
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Table A.2.2. Subchronic, Chronic and Other Toxicity Profile for Polybutene.

Guideline 

No. 

Study Type MRID No. (year)/ 

Classification /Doses

Results

870.5300 In Vitro Mammalian Cell 

Forward Mutation Assay 

(TK locus), Chinese 

hamster ovary cells strain 

AS52

43076603 (1993)

Acceptable/guideline

0.001, 0.003, 0.010, 0.033, 

0.10, 0.33 or 1.0 μL/mL in 

culture media, all tested with 

and without S9 activation.

NEGATIVE

There was no concentration-related 

increase in induced mutant colonies 

over background observed in the 

presence or absence of S9 

activation. Cytotoxicity was not 

observed; insolubility was observed 

at 0.33 and 1.0 μL/mL.

870.5385 In vivo bone marrow 

micronucleus assay, mouse

43076604 (1993)

Acceptable/guideline

1.25, 2.5 or 5 g/kg bw 

(intraperitoneal injection) with 

sacrifice at 24, 48 or 72 hr

NEGATIVE

There was no evidence of a 

clastogenic and/or aneugenic effect 

up to the limit dose of 5 g/kg bw. 

No systemic toxicity observed.

870.7485 Metabolism and 

pharmacokinetics (rat)

Not available.

870.6200a Acute Neurotoxicity (rat) Not available.

870.6200b Subchronic Neurotoxicity 

(rat)

Not available.

870.7800 Immunotoxicity Not available.