Docket Number: EPA-HQ-OPP-2010-0002 

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United States Prevention, Pesticides March 2010 

 Environmental Protection and Toxic Substances 

 Agency (7510P) 

 

Thymol Summary Document: 

Registration Review 

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TABLE OF CONTENTS 

Thymol Registration Review Team................................................................................. 4 

I. PRELIMINARY WORK PLAN – Thymol ................................................................ 5 

II. FACT SHEET ............................................................................................................ 15 

III. GLOSSARY of TERMS & ABBREVIATIONS ................................................... 19 

IV. APPENDIX A............................................................................................................ 21 
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Thymol Registration Review Team 

Human Health & Environmental Effects 

Nathan Mottl 

Jacob S. Moore 

Srinivas Gowda 

Risk Management

Monisha Harris 

Lance Wormell 

Andrew Bryceland 

Office of General Counsel

Philip Ross 
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I. PRELIMINARY WORK PLAN – THYMOL 

Introduction

The Food Quality Protection Act (FQPA) of 1996 mandated the registration 

review program. All pesticides distributed or sold in the United States generally must be 

registered by the U.S. Environmental Protection Agency (USEPA, EPA, or the Agency), 

based on scientific data showing that they will not cause unreasonable risks to human 

health or the environment when used as directed on product labeling. The registration 

review program is intended to make sure that, as the ability to assess risk evolves and as 

policies and practices change, all registered pesticides continue to meet the statutory 

standard of no unreasonable adverse effects to human health or the environment. Changes 

in science, public policy, and pesticide use practices will occur over time. Through the 

registration review program, the Agency periodically reevaluates pesticides to make sure 

that as change occurs, products in the marketplace can be used safely. Information on 

this program is provided at http://www.epa.gov/oppsrrd1/registration_review/. 

The Agency is implementing the registration review program pursuant to Section 

3(g) of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and will review 

each registered pesticide every 15 years to determine whether it continues to meet the 

FIFRA standard for registration. The Agency will consider benefits information and data 

as required by FIFRA. The public phase of registration review begins when the initial 

docket is opened for each case. The docket is the Agency’s opportunity to state what it 

knows about the pesticide and what additional risk analyses and data or information it 

believes are needed to make a registration review decision. After reviewing and 

responding to comments and data received in the docket during this initial comment 

period, the Agency will develop and commit to a final work plan and schedule for the 

registration review of Thymol. 

Thymol (PC Code 080402), also known as 2-isopropyl-5-methylphenol, is an 

organic phenol compound derived from thyme oil of plant, Thymus vulgaris (thyme) is 

produced synthetically from m-cresol. Thymol is an antimicrobial pesticide registered 

for limited use in indoor and outdoor residential, indoor non-food, indoor medical and 

terrestrial non-food sites. Thymol is registered for use in bathroom premises/hard 

surfaces, household/domestic dwellings, hospital/medical institutions, HVAC systems, 

schools, and nursing homes. Thymol is also registered for use as a biochemical pesticide 

to control Varroa mites in bee hives, and as a conventional pesticide repellent against tree 

squirrels, voles, dogs, and cats. Thymol was first registered in the United States in 1964. 

In September of 1993, the EPA issued a Reregistration Eligibility Decision (RED) for 

thymol. In January 2006, a Biopesticide Registration Action Document (BRAD) was 

completed for the new use of suppression of mites in honeybee colonies. EPA also 

registered a new antimicrobial use of thymol on heating, ventilation and air conditioning 

(HVAC) air ducts in 2004. In addition, an exemption from the requirement of a tolerance 

for honey and honeycombs was published in the Federal Register on January 18, 2006 

(71 FR 2889–2895). 
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The concentration of thymol in the 11 registered active products ranges from 

0.035% to 74.09% active ingredient (AI). There is currently no manufacturing use 

product containing thymol. 

A review of existing Agency registration and reregistration information indicates 

these additional highlights: 

• The FDA considers thymol, thyme essential oil, and thyme (spice) as 

Generally Recognized as Safe (GRAS) for use in foods, 21 CFR 182.20. 

• Thymol, thyme essential oil, and thyme (spice) are used in human food. 

• Thymol is also widely distributed as a food additive. 

• The Agency previously waived many of the existing toxicity data 

requirements in the RED; see the Tymol RED. 

• There is negligible human exposure to thymol as a result of pesticidal use 

patterns based on the low use rate and low frequency of application; see page 

8 of the Thymol RED. 

• Thymol degrades rapidly in the environment to elemental constituents by 

normal biological, physical, and/or chemical processes. 

• Once in the body, thymol is excreted rapidly. 

Risk Assessment Status & Anticipated Data Needs

Human Health Risk Assessment Status and Anticipated Data Needs

 The Agency has reviewed the hazard and exposure databases for the thymol 

registration review case. As a result of this review, the Agency does not expect that data 

or risk assessments will be needed to assess dermal, dietary, drinking water or incidental 

oral exposures. However, inhalation exposure may result from the application/use of 

thymol via pressure sprayers, aerosols, airless sprayers; pump-up garden type sprayers, 

ULV (ultra low volume) and mist generating sprayers (foggers). Therefore, the Agency 

anticipates needing additional inhalation and mutagenicity toxicity studies; upon review 

of these data, EPA will revisit the need for exposure data and an inhalation exposure risk 

assessment. 

Dietary and Drinking Water Exposure and Risk

Dietary Food Exposure 

 Thymol is found naturally in food stuffs such as lime honey and cooking herbs 

and/or food stuffs derived from cranberry and mandarin and tangerine oils. Thymol is 

also added to food stuffs commonly consumed by humans such as ice cream, nonalcoholic beverages, candy, baked goods, and chewing gum. It is FDA-approved when 

used as a synthetic flavoring (21 CFR 172.515), a preservative and indirect food additive 

of adhesives (21 CFR 172.105) and the source plant (thyme), from which thymol is 
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extracted is acknowledged by FDA as generally recognized as safe (GRAS)(21 CFR 

182.10, 21 CFR 182.20). 

 Dietary food risks of concern are not anticipated for the use of thymol as a 

pesticide for all registered uses; therefore, a dietary food assessment will not be 

performed. 

Dietary Drinking Water Exposure 

 Risks to thymol residues in drinking water are not expected since outdoor use is 

limited and thymol is GRAS therefore, release to drinking water sources is unlikely. 

Therefore, a dietary drinking water assessment will not be performed. 

Tolerances

 The following exemptions have been established for the use of thymol: 1) an 

exemption from the requirement of a tolerance has been established for residues of 

thymol (as present in thyme oil) in or on food commodities when applied/used in/on 

public eating places, dairy processing equipment, and/or food processing equipment and 

utensils (FRL-8404-4); and 2) an exemption from the requirement of a tolerance has been 

established for residues of thymol in or on honey and honeycomb when used in 

accordance with good agricultural practices (40 CFR 180.1240). 

Aggregate and Cumulative Exposure and Risk

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

reliable information concerning exposures to pesticide residues in food and drinking 

water, and non-occupational pesticide exposures. Dietary (food and drinking water) risks 

of concern are not anticipated for thymol. FDA considers thymol GRAS for use in foods 

and drinking water. Risks associated with thymol exposures are expected to be minimal 

through dermal and oral based on limited evidence of any subchronic or chronic systemic 

effects through the oral routes of exposure. Therefore, an aggregate assessment will not 

be needed. 

 Section 408(b)(2)(D)(v) of FFDCA requires that, when considering whether to 

establish, modify, or revoke a tolerance, the Agency consider "available information” 

concerning the cumulative effects of a particular pesticide's residues and "other 

substances that have a common mechanism of toxicity.” EPA has not yet determined 

whether thymol has a common mechanism with other compounds, consequently a 

cumulative assessment will not be performed at this time. 

Occupational and Residential Assessment and Risk

The Agency reviewed all available data associated with thymol and has 

determined that the currently registered uses of thymol may result in residential and 

occupational exposure. EPA expects dermal occupational and/or residential exposures 
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will likely be minimized based on the label use directions, PPE (e.g. gloves), dilution, 

and lack of systemic toxicity. Therefore, no additional dermal risk assessments are 

anticipated as being needed for registration review. The Agency will determine the need 

for occupational and/or residential inhalation risk assessments based on the results of the 

inhalation toxicity study which the Agency anticipates needing as part of registration 

review. 

The Biopesticides and Pollution Prevention Division (BPPD) does not anticipate the 

need for additional studies for thymol to support the use in bee hives. This bee hive use 

is the only biochemical use for this active ingredient. 

Anticipated Human Health Data Needs

The Agency anticipates requiring the following data for thymol. 

Anticipated Human Health Toxicity Data Needs

• (GLN 870.5915) In vivo sister chromosome exchange assay 

• (GLN 870.5900) In vitro sister chromosome exchange assay 

• (GLN 870.5375) In vitro mammalian chromosomal aberration test; and 

 • (GLN 870.5550) Unscheduled DNA synthesis, and 

• (GLN 870.3465) 90-day inhalation toxicity study 

Anticipated Occupational/Residential Exposure Data Needs

• (GLN 875.1400) Inhalation Exposure Indoor 

• (GLN 875.1600) Application Exposure Monitoring Data Reporting; and 

• (GLN 875.1700) Product Use Data 

Further information and detailed justifications for studies that are expected to be 

needed are available in “Summary of Human Health Effects Data for the Thymol 

Registration Review Decision Document,” dated March 23, 2010.

Anticipated Physical/Chemical Property Data Needs 

All product chemistry data requirements have been fulfilled for thymol. 

Therefore, it is anticipated that additional product chemistry data will not be needed for 

thymol. 

Environmental Fate and Ecological Risk Assessment Status and Anticipated Data 

Needs

The Agency reviewed the environmental fate and ecological hazard databases for 

thymol. The Agency has waived all environmental fate data requirements for thymol 

because of the relatively non-toxic nature of thymol, and its limited uses around 

residential areas. All of the ecotoxicity data requirements for thymol have been waived 

by the Agency because the ecotoxicity status is so well known for this active ingredient. 

Available data from literature reviews show that thymol is not toxic to aquatic organisms. 
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Based on thymol’s natural occurrence, current use patterns, toxicity data, 

low/non-toxicity, very low environmental exposure, and the lack of reported adverse 

effects information, the Agency does not anticipate conducting an environmental fate or 

ecological risk assessment for thymol. In addition, no environmental fate or ecological 

data are anticipated as being needed for this registration review. 

Based on the limited use patterns, very low exposure levels, the chemical's natural 

occurrence in the environment, common use as a food item, lack of reported adverse 

effects information, and very low/non-toxicity potential of thymol, the Agency 

anticipates concluding that the registered uses of thymol will have “no effect” (NE) on 

endangered or threatened terrestrial or aquatic species, or their designated critical 

habitats, as listed by the U.S. Fish and Wildlife Service (USFWS) and the National 

Oceanic and Atmospheric Administration's (NOAA) National Marine Fisheries Service 

(NMFS). EPA anticipates conducting no further analysis of potential risks to endangered 

or threatened species unless public comments provide additional information that would 

alter the Agency's current position that thymol will have "no effect" on such species or 

their designated critical habitat. 

Further information on the environmental fate and ecological risk assessment is 

available in the document titled, Summary of Product Chemistry, Environmental Fate, 

and Ecotoxicity Data for the Thymol Registration Review Decision Document, dated 

March 23, 2010. 

Incidents:

A search of the OPP Incident Data System (IDS) revealed no reported incidents 

for thymol. 

Timeline:

EPA has created the following estimated timeline for the completion of the 

thymol registration review: 

Anticipated Schedule

Activities Estimated Month/Year

Phase 1: Opening the docket 

Open Public Comment Period for Thymol Docket March 2010 

Close Public Comment Period May 2010 

Phase 2: Case Development 

Develop Final Work Plan (FWP) September 2010 

Issue DCI September 2011 

Data Submission September 2015 

Open Public Comment Period for Preliminary Risk Assessments March 2016 
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Close Public Comment Period June 2016 

Phase 3: Registration Review Decision 

Open Public Comment Period for Proposed Reg. Review Decision September 2016 

Close Public Comment Period December 2016 

Final Decision and Begin Post-Decision Follow-up 2017 

Total (years) 7 
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Guidance for Respondents:

The public is invited to comment on EPA’s preliminary registration review work 

plan and rationale. The Agency will carefully consider all comments as well as any 

additional information or data provided in a timely manner prior to issuing a final work 

plan for the thymol registration review case. 

Trade Irritants 

Through the registration review process, the Agency intends to solicit information 

on trade irritants and, to the extent feasible, take steps toward facilitating irritant 

resolution. Growers and other stakeholders are asked to comment on any trade irritant 

issues resulting from lack of Maximum Residue Limits (MRLs) or disparities between 

U.S. tolerances and MRLs in key export markets, providing as much specificity as 

possible regarding the nature of the concern. 

Water Quality 

Thymol is not identified as a cause of impairment for any water bodies listed as 

impaired under section 303(d) of the Clean Water Act, based on information provided at 

http://iaspub.epa.gov/tmdl_waters10/attains_nation_cy.cause_detail_303d?p_cause_grou

p_id=885. In addition, no Total Maximum Daily Loads (TMDL) have been developed 

for [insert pesticide], based on information provided at 

http://iaspub.epa.gov/tmdl_waters10/attains_nation.tmdl_pollutant_detail?p_pollutant_gr

oup_id=885&p_pollutant_group_name=PESTICIDES. More information on impaired 

water bodies and TMDLs can be found at http://www.epa.gov/owow/tmdl/. The Agency 

invites submission of water quality data for this pesticide. To the extent possible, data 

should conform to the quality standards in Appendix A of the OPP Standard Operating 

Procedure: Inclusion of Impaired Water Body and Other Water Quality Data in OPP’s 

Registration Review Risk Assessment and Management Process (see: 

http://www.epa.gov/oppsrrd1/registration_review/water_quality_sop.htm) in order to 

ensure they can be used quantitatively or qualitatively in pesticide risk assessments. 

Environmental Justice 

EPA seeks to achieve environmental justice, the fair treatment and meaningful 

involvement of all people, regardless of race, color, national origin, or income, in the 

development, implementation, and enforcement of environmental laws, regulations, and 

policies. To help address potential environmental justice issues, the Agency seeks 

information on any groups or segments of the population who, as a result of their 

location, cultural practices, or other factors, may have atypical, unusually high exposure 

to thymol compared to the general population. Please comment if you are aware of any 

sub-populations that may have atypical, unusually high exposure compared to the general 

population. 
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Structure Activity Relationships 

EPA must rely upon information of appropriate quality and reliability for each 

decision made by the Agency. In the Office of Pesticide Programs (OPP), the evaluation 

process for a pesticide chemical traditionally begins with the applicant’s submission of a 

set of studies conducted with the specific pesticide chemical of interest. The use of the 

results of such testing (measured data) is a logical, scientifically rigorous process that 

identifies the physical, chemical, and environmental fate properties of the pesticide, as 

well as the dose and endpoints at which an adverse effect can occur in various animal 

species. 

Today, there is significant interest in alternative techniques, i.e., techniques other 

than data generation that could significantly inform the Agency’s decision-making 

process. Recently, OPP has made increasing use of structure activity relationship (SAR) 

as part of its regulatory decision-making process. In the SAR process, a chemical's 

molecular structure is compared to that of other chemicals for which data are available. 

These structural similarities are then used to make predictive judgments about a 

chemical’s physical, chemical, and biological properties. Thus, the chemical’s physical, 

chemical, and biological properties are a function of (or directly related to) the chemical’s 

molecular structure. Quantitative SAR is referred to as QSAR. To develop a QSAR, a 

selected set of measured data on a single physical, chemical, or biological property is 

used to derive a model (an equation) to predict the value of that property. 

 Since SAR assessments and QSAR modeling are another set of tools that are 

available to Agency scientists, OPP has begun a process shift that envisions shifting from 

the current study-by-study approach to an approach in which the use of predicted data, 

generated using validated models, is considered along with information from open 

literature and studies specifically generated under Part 161 requirements. All relevant 

information would be considered as part of a weight-of-the-evidence evaluation. 

At this time, EPA believes that for certain endpoints, especially physical/chemical 

and fate properties, that SAR and QSAR might be effectively utilized to fulfill these data 

requirements for many antimicrobial pesticide chemicals. When considering biological 

properties, at this time, EPA believes that SAR and QSAR can be most effectively 

utilized in the evaluation of chemicals that exhibit lower toxicity for human health and/or 

ecotoxicity parameters. This is appropriate because the risk assessment for lower toxicity 

chemicals can be stream-lined, i.e., a screening-level assessment procedure rather than 

multiple tiers of assessments with progressively more data requirements. 

If stakeholders believe that submission of predicted data can fulfill one of the data 

needs for thymol, then the Agency invites submission of this information. The submitter 

would be expected to supply a rationale describing the utility of the information and 

provide documentation on the scientific validity of the information. The determination 

that the predicted data fulfills the data requirement would be at the sole discretion of the 

Agency. Pre-submission consultation with the Agency is encouraged. 
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Endocrine Disruptor Screening Program 

As required under FFDCA section 408(p), EPA has developed the Endocrine 

Disruptor Screening Program (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. 

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. This list of chemicals was selected based on the potential for human 

exposure through pathways such as food and water, residential activity, and certain postapplication agricultural scenarios. This list should not be construed as a list of known or 

likely endocrine disruptors. 

Thymol is not among the group of 58 pesticide active ingredients on the initial list 

to be screened under the EDSP. Under FFDCA sec. 408(p) the Agency must screen all 

pesticide chemicals. Accordingly, EPA anticipates issuing future EDSP test orders/data 

call-ins for all pesticide active ingredients. 

For further information on the status of the EDSP, the policies and procedures, the 

list of 67 chemicals, the test guidelines and the Tier 1 screening battery, please visit our 

website: http://www.epa.gov/endo/. 

Additional Information 

Stakeholders are also specifically asked to provide available information and data 

in the following areas: 

1. Confirmation on the following label information: 

a. Sites of application 

b. Formulations 

c. Application methods and equipment 

d. Maximum application rates 

e. Frequency of application, application intervals and maximum 

number of applications 

f. Geographic limitations on use 

2. Use or potential use distribution 
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3. Use history 

4. Usage/use information for non-agricultural uses (e.g., materials 

preservation) 

5. Typical application interval 

6. State or local use restrictions 

7. Ecological incidents (non-target plant damage and avian, fish, 

reptilian, amphibian and mammalian mortalities) not already reported 

to the Agency 

8. Monitoring data 

9. Structure Activity Relationships 

Next Steps: 

After the 60-day comment period closes, the Agency will review and respond to 

any comments received in a timely manner, and then issue a Final Work Plan for thymol. 
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II. FACT SHEET 

Background Information

• Chemical Name: Thymol 

• Common Names: 5-Methyl-2-isopropyl-1-phenol 

 5-Methyl-2-(1-methylethyl)phenol 

• Registration review case number: 3143 

• PC Code: 080402 

• CAS#: 89-83-8 

• There are no technical registrants for active products of Thymol. The following 

registrants have end use products containing thymol: Melaleuca Inc., OHSO 

Clean, Inc., and Wexford Labs, Inc.; Chemicals LAIF, Exosect Limited, and Vita 

(Europe) Limited; and MCB L.L.C. 

• First approved for use in a registered product: 1964 

• Eleven active registrations 

• Antimicrobials Division Chemical Review Manager (CRM): Monisha Harris, 

harris.monisha@epa.gov 

• Antimicrobials Division Product Manager (PM): Jacqueline CampbellMcFarlane, campbell-mcfarlane.jacqueline@epa.gov 

Chemical Structure:

Use & Usage Information

• Type of Pesticide: repellant, bacteriostat, fungicide/fungistat, disinfectant, 

mildewstat, tuberculocide, and virucide (antimicrobial). 

• Antimicrobial Use Sites:

o food handling/storage establishments premises 

o commercial, institutional and industrial premises and equipment 

 day cares, nurseries, fitness gyms, and spas 

 HVAC system and ducts 

o residential and public access premises 

 animal repellent 

 kitchen and food storage areas 

o medical premises and equipment 
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 intensive care, emergency rooms, nurseries, and dental operations 

 veterinary; chiropractic and physiotherapy clinics 

• Biopesticide Use Site:

o registered for use for the control of Varroa mites in bee hives. 

• Registered for use in indoor and outdoor residential, indoor non-food, indoor 

medical and terrestrial non-food sites. 

• Thymol has uses as an antiseptic, local anesthetic, cooling agent, and as 

a preservative. It is found in liniments, lip balms, toothpaste, and mouthwash. 

• Thymol as a conventional pesticide is registered for use as a repellent for tree 

squirrels, voles, dogs, and cats. 

• Thyme is used as a food seasoning ingredient, and is generally recognized as a 

safe (GRAS) natural seasoning by the Food and Drug Administration (FDA) (21 

CFR 182.10). 

• Thymol is also added to food stuffs commonly consumed by humans such as ice 

cream, non-alcoholic beverages, candy, baked goods, and chewing gum. 

Recent Regulatory Actions

There are no recent regulatory actions for thymol. A reregistration eligibility 

decision (RED) was issued in September 1993. 

http://www.epa.gov/pesticides/reregistration/status.htm 

Human Health Risk Assessment Status

The Agency has reviewed the hazard and exposure databases for the thymol 

registration and review case and anticipates that additional mutagenicity studies and a 90-

day inhalation toxicity study will be needed for registration review. Further information 

and detailed justifications for studies that are expected to be needed are available in 

“Summary of Human Health Effects Data for the Thymol Registration Review Decision 

Document,” dated March 23, 2010.

Environmental Fate & Ecological Risk Assessment Status

The Agency does not anticipate conducting further analyses of environmental fate 

and ecological risk or requiring additional data based on thymol’s natural occurrence, 

current use patterns, toxicity data, low/non-toxicity, very low environmental exposure, 

and the lack of reported adverse effects information. 

Further information on the environmental fate and ecological risk assessment is 

available in the document titled, “Summary of Product Chemistry, Environmental Fate, 

and Ecotoxicity Data for the Thymol Registration Review Decision Document,” dated 

March 23, 2010.
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Tolerances 

The following exemptions have been established for the use of thymol: 1) an 

exemption from the requirement of a tolerance has been established for residues of 

thymol (as present in thyme oil) in or on food commodities when applied/used in/on 

public eating places, dairy processing equipment, and/or food processing equipment and 

utensils(in the Federal Register of (March 25, 2009)(74FR12613)(FRL-8404-4)); and 2) 

an exemption from the requirement of a tolerance has been established for residues of 

thymol in or on honey and honeycomb when used in accordance with good agricultural 

practices (40 CFR 180.1240). 

Data Call-In Status

 

The Agency anticipates requiring additional data to complete a risk assessment 

during the registration review of this case. 

Labels 

There are 11 registered products that contain thymol. There are currently seven 

antimicrobial products, three biopesticide products, and one repellent product registered 

by the EPA containing thymol as an active ingredient. The EPA Registration Numbers 

are provided in Tables 1, 2, and 3 below. For future reference, during registration review 

a list of product registration numbers will be included in the docket. Product registration 

labels may be obtained from the Pesticide Product Label System (PPLS) website at: 

http://oaspub.epa.gov/pestlabl/ppls.home. 

Table 1. Registered Active Antimicrobial Products of Thymol (AD)

Registration # Registration Name Company Name Formulation Type % of Active 

Ingredient 

34810-18 Thymo-Cide Wexford Labs, Inc. Soluble Concentrate 13.00 

34810-25 Ready To Use Thymo-Cide Wexford Labs, Inc. Ready-to-Use 

Solution 0.051 

66251-2 SBT 2 To 1 Concentrate Melaleuca Inc. Soluble Concentrate 0.092 

84683-1 Benefect Broad Spectrum 

Disinfectant OHSO Clean, Inc. Ready-to-Use 

Solution 0.23 

84683-2 Benefect Biocide A.D. OHSO Clean, Inc. Ready-to-Use 

Solution 0.23 

84683-3 Benefect Botanical Daily 

Cleaner Disinfectant Spray OHSO Clean, Inc. Pressurized Liquid 0.05 

84683-4 Benefect Botanical Daily 

Cleaner Disinfectant Towelette OHSO Clean, Inc. Impregnated Materials 0.05 
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Table 2. Registered Active Biopesticide Products of Thymol (BPPD)

Registration # Registration Name Company Name Formulation 

Type 

% of Active 

Ingredient 

73291-1 Api Life Var Chemicals LAIF Pelleted/Tableted 74.09 

79442-11 ExomiteTM-Pro Exosect Limited Dust 6 

79671-1 Apiguard Vita (Europe) 

Limited Microencapsulated 25 

Table 3. Registered Active Repellent or Feeding Depressant Products of Thymol 

 (RD) 

Registration # Registration Name Company Name Formulation 

Type 

% of Active 

Ingredient 

81117-1 Ro-Pel® Tree Squirrel, Vole, 

Dog, And Cat Repellent MCB L.L.C. Ready-to-Use Solution 0.035 
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III. GLOSSARY of TERMS & ABBREVIATIONS

ai Active Ingredient 

AR Anticipated Residue 

ASTM American Society for Testing and Materials 

AWPA American Wood Preserver’s Association 

CFR Code of Federal Regulations 

cPAD Chronic Population Adjusted Dose 

CSF Confidential Statement of Formula 

CSFII USDA Continuing Surveys for Food Intake by Individuals 

DCI Data Call-In 

DEEM Dietary Exposure Evaluation Model 

DFR Dislodgeable Foliar Residue 

DNT Developmental Neurotoxicity 

DWLOC Drinking Water Level of Comparison 

EC Emulsifiable Concentrate Formulation 

EDWC Estimated Drinking Water Concentration 

EEC Estimated Environmental Concentration 

EPA Environmental Protection Agency 

EUP End-Use Product 

FDA Food and Drug Administration 

FIFRA Federal Insecticide, Fungicide, and Rodenticide Act 

FFDCA Federal Food, Drug, and Cosmetic Act 

FQPA Food Quality Protection Act 

FOB Functional Observation Battery 

GENEEC Tier I Surface Water Computer Model 

IR Index Reservoir 

LC50 Median Lethal Concentration. A statistically derived concentration of a 

substance that can be expected to cause death in 50% of test animals. It is 

usually expressed as the weight of substance per weight or volume of water, air 

or feed, e.g., mg/l, mg/kg or ppm. 

LD50 Median Lethal Dose. A statistically derived single dose that can be expected to 

cause death in 50% of the test animals when administered by the route indicated 

(oral, dermal, inhalation). It is expressed as a weight of substance per unit 

weight of animal, e.g., mg/kg. 

LOC Level of Concern 

LOAEL Lowest Observed Adverse Effect Level 

μg/g Micrograms Per Gram 

μg/L Micrograms Per Liter 

mg/kg/day Milligram Per Kilogram Per Day 

mg/L Milligrams Per Liter 

MOE Margin of Exposure 

MRID Master Record Identification (number). EPA's system of recording and tracking 

submitted studies. 

MUP Manufacturing-Use Product 

NA Not Applicable 

NAWQA USGS National Ambient Water Quality Assessment 

NPDES National Pollutant Discharge Elimination System 

NR Not Required 

NOAEL No Observed Adverse Effect Level 

OPP EPA Office of Pesticide Programs 

OPPTS EPA Office of Prevention, Pesticides and Toxic Substances 

PAD Population Adjusted Dose 

PAIRA Pure Active Ingredient Radiolabelled 

PCA Percent Crop Area 

PDP USDA Pesticide Data Program 
Docket Number: EPA-HQ-OPP-2010-0002 

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 20 of 34 

PHED Pesticide Handler's Exposure Data 

PHI Preharvest Interval 

ppb Parts Per Billion 

PPE Personal Protective Equipment 

ppm Parts Per Million 

PRZM/EXAMS Tier II Surface Water Computer Model 

Q1* The Carcinogenic Potential of a Compound, Quantified by the EPA's Cancer 

Risk Model 

RAC Raw Agriculture Commodity 

RED Reregistration Eligibility Decision 

REI Restricted Entry Interval 

RfD Reference Dose 

RQ Risk Quotient 

SCI-GROW Tier I Ground Water Computer Model 

SAP Science Advisory Panel 

SF Safety Factor 

SLN Special Local Need (Registrations Under Section 24©) of FIFRA) 

TGAI Technical Grade Active Ingredient 

TEP Typical End-Use Product 

USDA United States Department of Agriculture 

UF Uncertainty Factor 

WPS Worker Protection Standard 
Docket Number: EPA-HQ-OPP-2010-0002 

www.regulations.gov 21 of 34 

IV. APPENDIX A

Use Patterns for THYMOL 

Food Handling/ Storage Establishments Premises and Equipment 

Use Site Formulation Method of 

Application 

Application Rate/ No. of 

applications 

Use 

Food Area Premises and Equipment – Indirect Food Contact

Food preparation facilities; restaurants and bars; kitchens; cafeterias; food storage areas: Non-porous surfaces e.g. countertops, sinks, food preparation surfaces. 

Areas Without Potential for 

Food Contact

Food preparation facilities; restaurants and bars; kitchens; cafeterias; food storage areas: Non-porous surfaces e.g. toilet seats, garbage cans, highchairs. Porous and semi-porous surfaces including carpets, pads, sub-floors, drywall, studding, trim and lumber, other similar construction 

Ready-to-use solution 84683-1 84683-3 Pressurized liquid 84683-3 

Spray To clean: Preclean. Shake, apply 

product and wipe away. To disinfect: Shake well and wet surface with spray. Expose for 10 minutes, allow to air dry. No rinsing or wiping is required except on direct oral, skin or food contact surfaces which require potable water rinse after treatment. 
Docket Number: EPA-HQ-OPP-2010-0002 

www.regulations.gov 22 of 34 

materials. 
Docket Number: EPA-HQ-OPP-2010-0002 

www.regulations.gov 23 of 34 Food Handling/ Storage Establishments Premises and Equipment 

Use Site Formulation Method of 

Application 

Application Rate/ No. of 

applications 

Use 

Food Area Premises and Equipment – Indirect Food Contact

Food preparation facilities; restaurants and bars; kitchens; cafeterias; food storage areas: Non-porous surfaces e.g. countertops, sinks, food preparation surfaces. 

Areas Without Potential for 

Food Contact

Food preparation facilities; restaurants and bars; kitchens; cafeterias; food storage areas: Non-porous surfaces e.g. toilet seats, garbage cans, highchairs. Porous and semi-porous surfaces including carpets, pads, sub-floors, drywall, studding, trim and lumber, other similar construction materials. 

Impregnated materials 84683-4 

Wipe Wet the surface with wipe. 

Contact time 10 minutes. Wipe clean. 
Docket Number: EPA-HQ-OPP-2010-0002 

www.regulations.gov 24 of 34 Commercial, Institutional and Industrial Premises and Equipment 

Use Site Formulation Method of 

Application 

Application Rate/ No. of 

applications 

Use 

Indoor

Commercial/Institutional Industrial Premises/Equipment 

Schools - floors, walls bathroom fixtures, shower room stalls 

Soluble concentrate 34810-18 34810-19 

Cloth, mop or brush 

Use 1.5 oz of product per 1 gal water. Wet all surfaces thoroughly for at least 10 minutes. Remove gross filth and heavy soil before application. 

Indoor

Commercial/Institutional Industrial Premises/Equipment 

Day cares; nurseries; fitness gyms; spas: Hard, non-porous surfaces e.g. countertops, sinks, toilet seats, construction materials. Porous and semi-porous surfaces e.g. carpets, pads, sub-floors, drywall, studding, trim and lumber, other construction materials. 

Ready-to-use solution 84683-1 84683-3 Pressurized liquid 84683-3 

Spray To clean: Preclean. Shake, apply 

product and wipe away. To disinfect: Shake well and wet surface with spray. Expose for 10 minutes, allow to air dry. No rinsing or wiping is required except on direct oral, skin or food contact surfaces which require potable water rinse after treatment. 
Docket Number: EPA-HQ-OPP-2010-0002 

www.regulations.gov 25 of 34 Commercial, Institutional and Industrial Premises and Equipment

Use Site Formulation Method of 

Application 

Application Rate/ No. of 

applications 

Use 

Indoor

Commercial/Institutional Industrial Premises/Equipment 

Day cares; nurseries; fitness gyms; spas: Hard, non-porous surfaces e.g. countertops, sinks, toilet seats, construction materials. Porous and semi-porous surfaces e.g. carpets, pads, sub-floors, drywall, studding, trim and lumber, other construction materials. 

Impregnated materials 84683-4 

Wipe Wet the surface with wipe. 

Contact time 10 minutes. Wipe clean. 

Indoor

Commercial/Institutional/ Industrial Premises/Equipment (Indoor) 

HVAC System and Ducts 

Ready-to-use solution 84683-2 

Brush, mop, wipe, spray, ULV or mist generator, atomize/spray 

Shake well and wet surfaces with spray. Allow 10 - 20 minutes for drying. No rinse or wipe required. Details may vary according to application method. 
Docket Number: EPA-HQ-OPP-2010-0002 

www.regulations.gov 26 of 34 Residential and Public Access Premises 

Use Site Formulation Method of 

Application 

Application Rate/ No. of 

applications 

Use 

Non-Food Indoor

Household/Domestic Dwellings Contents 

Hotels and motels; zoos and kennels: Hard, non-porous surfaces -Faucets, sinks, drains, doorknobs, telephones, kitchen appliances, sports equipment, children’s toys, etc. 

Soluble concentrate 66251-2 

Spray Dilute 8.5 oz of product per 8.5 

oz water. Avoid splashing. To clean: Spray diluted product on area to be cleaned until thoroughly wet and wipe or rinse away. To sanitize: Spray diluted product on surface until thoroughly wet. Let stand 1 minute. Wipe or air dry. To disinfect: Preclean. Spray diluted product on surface until thoroughly wet. Let stand 10 minutes before wiping. No rinsing necessary. 
Docket Number: EPA-HQ-OPP-2010-0002 

www.regulations.gov 27 of 34 Residential and Public Access Premises

Use Site Formulation Method of 

Application 

Application Rate/ No. of 

applications 

Use 

Non-Food Indoor/Outdoor

Household/Domestic Dwellings Outdoor premises 

Tree squirrel, vole, dog, cat repellent for use on outdoor structures and surfaces such as brown bark of trees, fences, poles, decks, planters, siding, garbage cans, furniture, seeds and bulbs 

Ready-to-use solution 81171-1 

Spray, brush Use a sprayer capable of 

delivering a coarse droplet spray (such as a tank sprayer). Spray all surfaces to the point of runoff, or treat by painting with a brush. Make a second application in 24 days to improve effectiveness. Using rubber gloves, place seeds or bulbs in a plastic or metal container and spray until thoroughly soaked. Allow to dry. Repeat application in areas of high animal pressure. Then plant in normal manner. 

Use at full strength; do with any other chemicaApply to dry surfaces. Ppainted/stained surfacessmall area first to determDo not use this product > 900° F. Do not use mist blowerapplication equipment tDo not apply product on or if precipitation is pre
Docket Number: EPA-HQ-OPP-2010-0002 

www.regulations.gov 28 of 34 Residential and Public Access Premises

Use Site Formulation Method of 

Application 

Application Rate/ No. of 

applications 

Use 

Indirect Food Contact

Household/Domestic Dwellings 

Kitchens, food storage areas: Hard, non-porous surfaces e.g. countertops, sinks, food preparation surfaces 

Non-food Indoor

Household/Domestic Dwellings Contents 

Hard, non-porous surfaces e.g. toilet seats, pet habitats, garbage cans, children’s toys, highchairs, sports equipment, construction materials Porous and semi-porous surfaces including carpets, pads, sub-floors, drywall, studding, trim and lumber, other construction materials 

Ready-to-use solution 84683-1 84683-3 Pressurized liquid 84683-3 

Spray To clean: Preclean. Shake, apply 

product and wipe away. To disinfect: Shake well and wet surface with spray. Expose for 10 minutes, allow to air dry. No rinsing or wiping is required except on direct oral, skin or food contact surfaces which require potable water rinse after treatment. 
Docket Number: EPA-HQ-OPP-2010-0002 

www.regulations.gov 29 of 34 Residential and Public Access Premises

Use Site Formulation Method of 

Application 

Application Rate/ No. of 

applications 

Use 

Indirect Food Contact

Household/Domestic Dwellings 

Kitchens, food storage areas: Hard, non-porous surfaces e.g. countertops, sinks, food preparation surfaces 

Non-food Indoor

Household/Domestic Dwellings Contents 

Hard, non-porous surfaces e.g. toilet seats, pet habitats, garbage cans, children’s toys, highchairs, sports equipment, construction materials Porous and semi-porous surfaces including carpets, pads, sub-floors, drywall, studding, trim and lumber, other construction materials 

Impregnated materials 84683-4 

Wipe Wet the surface with wipe. 

Contact time 10 minutes. Wipe clean. 
Docket Number: EPA-HQ-OPP-2010-0002 

www.regulations.gov 30 of 34 Medical Premises and Equipment 

Use Site Formulation Method of 

Application 

Application Rate/ No. of 

applications 

Use 

Hospital/Medical Institutions Non-Critical Premises 

Hospitals, health care facilities, nursing homes - floors, walls bathroom fixtures, shower room stalls 

Soluble concentrate 34810-18 34810-19 

Cloth, mop or brush 

Use 1.5 oz of product per 1 gal water. Wet all surfaces thoroughly for at least 10 minutes. Remove gross filth and heavy soil before application. Special instructions for surfaces/objects soiled with blood/body fluids which may contain HIV.I (AIDS VIRUS). Contact time 1 minute. For lightly soiled areas wipe off visual soil/clean with product and disinfect with second application. For large spills the contaminated areas should be flooded with product before cleaning, then decontaminated with fresh product. 

This product is not to be sterilant/high level disininstrument that (1) is inhuman body, either into bloodstream or normall(2) contacts intact muconot ordinarily penetrate enter normally sterile ar
Docket Number: EPA-HQ-OPP-2010-0002 

www.regulations.gov 31 of 34 Medical Premises and Equipment

Use Site Formulation Method of 

Application 

Application Rate/ No. of 

applications 

Use 

Hospital Critical Items Hospital Semi-Critical Items 

Soluble Concentrate 34810-18 34810-19 

Wipe, pour For lightly soiled areas wipe off 

visual soil/clean with product, and disinfect surface with a second application. For large spills the contaminated areas should be flooded with the product before cleaning, then decontaminated with product. Special instructions for surfaces/objects soiled with blood/body fluids which may contain HIV.I (AIDS VIRUS). Contact time 1 minute. For lightly soiled areas wipe off visual soil/clean with product and disinfect with second application. For large spills the contaminated areas should be flooded with product before cleaning, then decontaminated with fresh product. 

This product is not to be sterilant/high level disininstrument that (1) is inhuman body, either into bloodstream or normall(2) contacts intact muconot ordinarily penetrate enter normally sterile ar
Docket Number: EPA-HQ-OPP-2010-0002 

www.regulations.gov 32 of 34 Medical Premises and Equipment

Use Site Formulation Method of 

Application 

Application Rate/ No. of 

applications 

Use 

Hospital/Medical Institutions Critical premises 

Hard, non-porous sur6rs, in operating rooms, intensive care, nurseries, emergency areas, dental operatories, EMS, and other emergency response areas, for working surfaces, stainless steel, chrome, glass and vinyl. 

Ready-to-use solution 34810-22 34810-25 

Cloth, brush, immersion 

Wet all hard surfaces thoroughly. Expose for at least 10 minutes before drying with a cloth. Remove gross filth and heavy soil before application. Special instructions for surfaces/objects soiled with blood/body fluids which may contain HIV.I (AIDS VIRUS). Contact time 1 minute. For lightly soiled areas wipe off visual soil/clean with product and disinfect with second application. For large spills the contaminated areas should be flooded with product before cleaning, then decontaminate with fresh product. 

Do not mix with other ccleaners. This product is not to be sterilant/high level disininstrument that (1) is inhuman body, either into bloodstream or normall(2) contacts intact muconot ordinarily penetrate enter normally sterile ar
Docket Number: EPA-HQ-OPP-2010-0002 

www.regulations.gov 33 of 34 Medical Premises and Equipment

Use Site Formulation Method of 

Application 

Application Rate/ No. of 

applications 

Use 

Hospital /Medical Institutions Non-critical Premises 

Hospitals; nursing homes; medical veterinary and dental offices; health professional, chiropractic & physiotherapy clinics. Hard, non-porous surfaces e.g. countertops, sinks, toilet seats, garbage cans, prostheses and orthotics, construction materials Porous and semi-porous surfaces e.g. carpets, pads, sub-floors, drywall, studding, trim and lumber, other construction materials 

Ready-to-use solution 84683-1 84683-3 Pressurized liquid 84683-3 

Spray To clean: Preclean. Shake, apply 

product and wipe away. To disinfect: Shake well and wet surface with spray. Expose for 10 minutes, allow to air dry. No rinsing or wiping is required except on direct oral, skin or food contact surfaces which require potable water rinse after treatment. Special instructions for surfaces/objects soiled with blood/body fluids which may contain HIV.I (AIDS VIRUS). Contact time 1 minute. For lightly soiled areas wipe off visual soil/clean with product and disinfect with second application. For large spills the contaminated areas should be flooded with product before cleaning, then decontaminated with fresh product. 

This product is not to be sterilant/high level disininstrument that (1) is inhuman body, either into bloodstream or normall(2) contacts intact muconot ordinarily penetrate enter normally sterile ar
Docket Number: EPA-HQ-OPP-2010-0002 

www.regulations.gov 34 of 34 Medical Premises and Equipment

Use Site Formulation Method of 

Application 

Application Rate/ No. of 

applications 

Use 

Hospital /Medical Institutions Non-critical Premises 

Hospitals; nursing homes; medical veterinary and dental offices; health professional, chiropractic & physiotherapy clinics. Hard, non-porous surfaces e.g. countertops, sinks, toilet seats, garbage cans, prostheses and orthotics, construction materials Porous and semi-porous surfaces e.g. carpets, pads, sub-floors, drywall, studding, trim and lumber, other construction materials 

Impregnated materials 84683-4 

Wipe Wet the surface with wipe. 

Contact time 10 minutes. Wipe clean.