Docket Number: EPA-HQ-OPP-2010-0467 

www.regulations.gov

Chlorfenapyr Summary Document 

Registration Review: Initial Docket 

June 2010 

3 

TABLE OF CONTENTS 

 Page # 

I. Preliminary Work Plan 4 

II. Fact Sheet 10 

________________________________________ 

Please Note 

This Preliminary Work Plan (PWP) and Fact Sheet summarize the Environmental Protection 

Agency’s current position based on the following documents: 

1. Registration Review—Preliminary Problem Formulation for the Ecological Risk, 

Environmental Fate, and Endangered Species Assessments for Chlorfenapyr (PC Code 

129093; DP Barcode 373109). May 11, 2010. 

2. Chlorfenapyr. Human-Health Assessment Scoping Document in Support of Registration 

Review. May 26, 2010. 

3. Appendix A: Food/Feed & Non-Food/Non-Feed Uses Considered in Registration 

Review Work Planning. Chlorfenapyr (129093). June 8, 2009

4. Chlorfenapyr (129093) California Department of Pesticide Regulation (DPR) Usage 

Data. June 30, 2009

5. Chlorfenapyr: Review of Human Incidents. February 25, 2010

The supporting documents for chlorfenapyr may be found in the docket EPA-HQ-OPP-2010-

0467, located on the internet at <www.regulations.gov>.
4 

I. Preliminary Work Plan - Chlorfenapyr 

Introduction:

The Food Quality Protection Act of 1996 mandated a pesticide registration review program. All 

pesticides distributed or sold in the United States generally must be registered by EPA, 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 other 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 chlorfenapyr. 

Chlorfenapyr (case number 7419) is a pyrrole insecticide and miticide used in greenhouses and 

other structures to control mites, termites, spiders, and insects. Use of chlorfenapyr is allowed in 

residential settings, but applications can only be made by certified professional applicators. 

Chlorfenapyr is a pro-insecticide (i.e., the biological activity depends on its activation to another 

chemical). The parent compound is converted to the N-dealkylated metabolite, which functions 

as an uncoupler of oxidative phosphorylation in mitochondria. Chlorfenapyr was first registered 

in 2001 and therefore was not subject to the reregistration process under FIFRA. 

Anticipated Risk Assessment and Data Needs:

The Agency anticipates conducting comprehensive human health and ecological risk 

assessments, including an endangered species assessment, for all uses of chlorfenapyr and its 

metabolites of concern. Below is a summary of the issues relevant to the registration review 

process for chlorfenapyr. 

Ecological Risk: 

The most recent ecological risk assessment was conducted in 1998 to support the initial 

registration of chlorfenapyr in 2001. There are two uses of chlorfenapyr that could potentially 

result in environmental exposures: (1) distribution of composted material from greenhouses that 

use chlorfenapyr; and (2) application of chlorfenapyr to soil underlying a concrete slab prior to 

the slab being poured (during construction). All other uses occur indoors, underground 
5 

(termiticide), or involve small quantities (crack and crevice treatment) and are not expected to 

result in significant ecological exposure because greenhouse/indoor and underground uses have 

limited opportunity for outdoor residues, drift, runoff, and wildlife exposure. To assess the potential 

risk from the two abovementioned uses of chlorfenapyr (crack and crevice), additional data are 

anticipated to be required and a subsequent risk assessment will be performed. The Agency will 

also complete an endangered species assessment for all pesticide uses of chlorfenapyr. A 

summary of the anticipated needs for the ecological assessment follows: 

• The Agency anticipates needing the following data in order to conduct a complete 

ecological risk assessment for chlorfenapyr, including an endangered species assessment: 

o Guideline 850.4100, 4150, 4400, 5400 - Aquatic and Terrestrial Plant Toxicity. 

(Tier II, chlorfenapyr). Registrants may opt to conduct a Tier I study, with the 

understanding that any adverse effects (even if less than 25 percent) will 

necessitate a Tier II study. A Tier II study will enable the Agency to conduct an 

endangered species assessment for nontarget plants. 

o Guideline 850.1735 and 850.1740 - Whole Sediment: Freshwater and Marine 

Invertebrates. (chlorfenapyr) 

o Guideline 850.1075 - Fish Acute LC50 (Rainbow Trout). (photolysis degradate 

CL 357,806) 

o Guideline 850.1025 - Estuarine/Marine Acute Invertebrate LC50 (Eastern 

Oyster). (chlorfenapyr) 

o Guideline 850.1400 - Fish Early-life Stage Toxicity Test. (chlorfenapyr) 

o Guideline 835.6100 (Footnote 7) – Environmental Chemistry Analytical Method. 

(soil) 

o Guideline 835.6200 (Footnote 7) - Environmental Chemistry Analytical Method. 

(water) 

o Special Study - Evaluation of Chlorfenapyr Degradation in Compost. 

(chlorfenapyr)

• The Agency has not conducted a risk assessment that supports a complete endangered 

species determination for chlorfenapyr. The ecological risk assessment planned during 

registration review will allow the Agency to determine whether chlorfenapyr’s use has 

“no effect” or “may affect” federally listed threatened or endangered species (listed 

species) or their designated critical habitat. When an assessment concludes that a 

pesticide’s use “may affect” a listed species or its designated critical habitat, the Agency 

will consult with the U.S. Fish and Wildlife Service and/or National Marine Fisheries 

Service (the Services), as appropriate. 

• Refer to the document, Registration Review - Preliminary Problem Formulation for 

Ecological Risk, Environmental Fate, and Endangered Species Assessments for 

Chlorfenapyr (PC Code 129093; DP Barcode 373109), for a detailed discussion of the 

anticipated ecological risk assessment needs. 
6 

Human Health Risk: 

The most recent risk assessment was conducted in 2003 to support the initial registration of 

greenhouse food crops and establishment of tolerances for fruiting vegetables (crop group 8). A 

summary of the anticipated needs for the human health assessment follows:

• The Agency anticipates needing the following data in order to conduct a complete human 

health risk assessment for chlorfenapyr: 

o Guideline 870.3200 - 28-day Dermal Toxicity (rat) (chlorfenapyr) 

o Guideline 870.3465 - 90-day Inhalation Toxicity (rat) (chlorfenapyr) 

o Guideline 870.7800 - Immunotoxicity (chlorfenapyr) 

• As part of registration review, the Agency anticipates conducting a new dietary risk 

assessment which utilizes the most current version of DEEM-FCIDTM (2.03), does not 

include DEEMTM default processing factors (which are not appropriate for a food 

handling establishment (FHE) use as residues would be expected to be incurred after 

processing) or citrus processing factors, and includes tolerances for the currently 

registered uses on greenhouse-grown fruiting vegetable crop group 8 commodities and 

FHE only. The new dietary exposure assessment should also evaluate potential secondary 

residues of chlorfenapyr and its metabolites in/on livestock commodities due to 

consumption of feed items with chlorfenapyr residues resulting from the established 

food/feed handling area use. If any proposed uses of chlorfenapyr are deemed to result in 

contamination of drinking water, estimated drinking water concentrations (EDWCs) will 

need to be incorporated into future dietary assessments. 

• Livestock dietary burdens should be reassessed to evaluate potential secondary residues of 

chlorfenapyr and its metabolites in/on livestock commodities due to consumption of feed 

items with chlorfenapyr residues resulting from the established food/feed handling area 

use. 

• As part of registration review, the Agency expects to conduct a revised residential 

postapplication and occupational handler and postapplication assessment. The revised 

residential assessment would need to include dermal and incidental oral routes of 

exposure. Two occupational handler scenarios would need to be assessed during 

registration review and, in addition, several occupational handler scenarios may need to be 

reassessed in accordance with changes to the hazard assessment. The occupational post 

application exposure assessment would need to reassessed based on current labeled 

application rates and updated transfer coefficients and may also need to be reassessed in 

accordance with changes to the hazard assessment. 

• The tolerance expression in 40 CFR Part 180.513 will be reviewed during registration 

review to ensure that it appropriately covers the metabolites and degradates of 

chlorfenapyr and that it specifies the residues to be measured for each commodity. 

• In future risk assessments for chlorfenapyr, the FQPA factor will need to be updated based 

upon the changes in policy, the submitted developmental neurotoxicity study (DNT), 

along with the immunotoxicity, 28-dermal and 90-day inhalation studies when submitted, 

may lead to revision of the current endpoints for future risk assessments. 
7 

• Please refer to the document, Chlorfenapyr - Human Health Assessment Scoping 

Document in Support of Registration Review, for a detailed discussion of the anticipated 

risk assessment and data needs for human health. 

Other anticipated data needs:

• Guideline 830.7050 - UV/Visible Light Absorption. This study is a new data 

requirement under 40 CFR Part 158 for registration of a pesticide (food and non-food 

uses). The Agency anticipates requiring this study to obtain basic information about the 

compound’s identity/composition and the wavelengths at which the compound may be 

susceptible to photochemical degradation. 

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 quantitative 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 post-application agricultural scenarios. 

This list should not be construed as a list of known or likely endocrine disruptors. 

Chlorfenapyr 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 EDSP orders/data call-ins for all Registration 

Review cases, including those for which EPA has already opened a Registration Review docket 

for a pesticide active ingredient. 

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/.

Timeline:

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

registration review. 
8 

Registration Review for Chlorfenapyr – Projected Registration Review Timeline

Activities Estimated Date 

Opening the docket 

Open Docket and Public Comment Period 2010 – June 

Close Public Comment 2010 – August 

Case Development 

Final Work Plan 2010 – November 

Issue DCI 2011 – July – Sept. 

Data Submission 2013 – July – Sept. 

Open Public Comment Period for Preliminary Risk Assessments 2015 – Jan. – March 

Close Public Comment Period 2015 – April - June 

Registration Review Decision 

Open Public Comment Period for Proposed Registration Review Decision 2015 – July - Sept. 

Close Public Comment Period 2015 – Oct. – Dec. 

Final Registration Review Decision and Begin Post-Decision Follow-up 2016 

Total (years) 6 

Guidance for Commenters:

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 

chlorfenapyr 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: 

Chlorfenapyr 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_group_id=88

5. In addition, no Total Maximum Daily Loads (TMDL) have been developed for chlorfenapyr, 

based on information provided at 

http://iaspub.epa.gov/tmdl_waters10/attains_nation.tmdl_pollutant_detail?p_pollutant_group_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. 
9 

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 chlorfenapyr 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. 

Additional Information: 

Stakeholders are also specifically asked to provide information and data that will assist the 

Agency in refining the risk assessments, including any species-specific ecological effects 

determinations. The Agency is interested in obtaining the following information regarding the 

use of chlorfenapyr: 

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 

per season 

f. geographic limitations on use 

2. use or potential use distribution 

3. use history 

4. state or local use restrictions 

5. ecological incidents (non-target plant damage and avian, fish, reptilian, amphibian and 

mammalian mortalities) not already reported to the Agency 

6. monitoring data 

Next Steps:

After the 60-day comment period closes, the Agency will consider and respond to any comments 

received in a timely manner, and then issue a Final Work Plan for this pesticide in the fall of 

2010. 
10 

II. FACT SHEET: Chlorfenapyr Registration Review 

Background Information:

• Chlorfenapyr registration review case number: 7419 

• Chlorfenapyr Pesticide Chemical (PC) Code: 129093 

• Chlorfenapyr Chemical Abstracts Service (CAS) number: 122453-73-0 

• Chlorfenapyr was first registered in the United States in 2001 as a foliar spray for 

ornamental crops grown in greenhouses (non-food use). 

• BASF Corporation is the only technical registrant for chlorfenapyr. 

• There are four chlorfenapyr products registered under FIFRA Section 3. There is also 

one Special Local Need (SLN) registration in Mississippi. 

• Pesticide Re-Evaluation Division (PRD), Chemical Review Manager (CRM): Susan 

Bartow: bartow.susan@epa.gov 

• Registration Division (RD) contact: 

Richard Gebken: gebken.richard@epa.gov. 

Use & Usage Information: (For additional details, please refer to the Biological and Economic 

Analysis Division (BEAD) Appendix A document in the chlorfenapyr docket.) 

• Chlorfenapyr is an insecticide registered for use to control a variety of insects on 

terrestrial non-food crops, aquatic non-food industrial sites, greenhouse food and nonfood crops, outdoor residential, indoor food and non-food uses, indoor medical, and 

indoor residential. 

• Target pests include mites, caterpillars, centipedes, thrips, fungus gnats, ants, 

cockroaches, beetles, bed bugs, silverfish, spiders, and termites. 

• Chlorfenapyr is sold in emulsifiable concentrate and pressurized liquid forms. 

• Use is allowed in residential settings, but applications can only be made by certified 

professional applicators. 

• Chlorfenapyr is applied via aerosol can, low pressure sprayer, foam applicator, injection 

equipment, hand pressure sprayer, low volume sprayer, power sprayer, and pump spray 

bottle. 

Recent Actions:

• In 2003, chlorfenapyr was first registered for greenhouse food crops and tolerances were 

established for fruiting vegetables (crop group 8). 

• In 2006, chlorfenapyr was first registered for indoor and outdoor residential uses, indoor 

non-food, terrestrial non-food crops, and aquatic non-food industrial uses. 
11 

• In 2009, additional use sites were registered for chlorfenapyr (e.g., zoos, windows, 

furniture, sewers, drains). 

Ecological Risk Assessment Status: 

The following are key findings of the most recent chlorfenapyr ecological risk assessment, 

conducted in support of the initial registration of chlorfenapyr. Please refer to Registration 

Review – Preliminary Problem Formulation for the Ecological Risk, Environmental Fate, and 

Endangered Species Assessments of Chlorfenapyr for a detailed discussion of the ecological risk 

assessment. 

Sediment Persistence: 

• Chlorfenapyr and its degradates have been shown to be highly persistent. Chlorfenapyr’s 

persistence is typified by a laboratory aerobic soil metabolism half-life of 1.4 years and 

its observed comparable field dissipation “half-life” of 1.3 years. Chlorfenapyr is 

essentially stable to laboratory hydrolysis and anaerobic soil metabolism. Chlorfenapyr 

also has an organic carbon partition coefficient (Koc) of 11,500 L/kg and thus binds to 

organic particulates and is generally immobile in soil. Sediment would be its principal 

latent reservoir in aquatic systems where it would remain available for extended periods. 

Because of the persistence of the parent and relatively short study durations, only small 

amounts of structurally similar metabolites or degradates were identified in soil in field or 

laboratory studies. However, the degradate AC 312,094 has been detected at 10 percent 

to 16 percent of parent in the radiolabeled North Carolina study. This metabolite has 

intermediate mobility characteristics (median Koc around 2200). Coupled with its 

persistence, this means that it has high potential for runoff into surface water with 

comparable amounts in solution and eroding soil if chlorfenapyr is used in outdoor 

environments. 

In general, transformation products appear to approximate or exceed the persistence of 

the parent. Structurally similar metabolites or degradates (AC 312,094, AC 303,267, AC 

303,268, AC 322,118, AC 322,250, AC 325,195, some of which exhibit ecotoxicity) 

were identified in soil in field or lab studies. Concentrations of these, when detected 

were typically a few percent each or less of the applied chlorfenapyr. 

Terrestrial Animal Toxicity (Birds, Mammals, and Invertebrates): 

• Chlorfenapyr is very highly toxic to birds on an acute basis. The LD50 values for redwinged blackbird (Agelaius phoneiceus), mallard (Anas platyrhynchus), and bobwhite 

quail (Colinus virginianus) are 2.2, 8.3, and 34 mg/kg, respectively. It is also very highly 

toxic to waterfowl and passerine species and highly toxic to upland gamebirds on an 

acute dietary basis. Chlorfenapyr has also resulted in reproductive and growth effects to 

birds at low concentrations of 1.5 mg/kg-diet. The mallard duck NOAEC value of 0.5 

mg/kg-diet, which is based on reduced body weight, serves as the chronic toxicity 

endpoint for avian long-term exposure risk calculations. 

• Chlorfenapyr has been shown to be less toxic to mammals as compared with birds. Acute 

LD50 values in mammals range from approximately 45 mg/kg-bw to 1152 mg/kg-bw. A 

2-generation mammalian study produced a No Observed Adverse Effect Concentration 

(NOAEC) value of 60 mg/kg-diet (5 mg/kg-bw). 
12 

• Chlorfenapyr is highly toxic to honey bees (Apis mellifera) on an acute contact exposure 

basis with a corresponding LD50 value of 0.12 μg/bee. 

Aquatic Animal Toxicity (Fish and Aquatic Invertebrates): 

• In aquatic organisms, acute LC50 values for chlorfenapyr range from 7 μg/L to 12 μg/L in 

freshwater fish, 60 μg/L in saltwater fish, 6 μg/L to 18 μg/L in freshwater invertebrates, 2 

μg/L in saltwater invertebrates, and 0.2 mg/kg to 20 mg/kg sediment in benthic 

organisms. Therefore, on an acute exposure basis, chlorfenapyr is very highly toxic to 

freshwater and estuarine/marine fish and invertebrates. Also, based on an unacceptable 

study, one of the degradates (CL 357,806) appears to be more toxic than the parent 

chemical. 

• Chronic NOAEC values range from 0.2 μg/L in estuarine/marine invertebrates to 4 μg/L 

in freshwater fish and invertebrates. 

Human Health Risk Assessment Status:

The following are key findings of the most recent chlorfenapyr human health risk assessment. 

Please refer to Chlorfenapyr - Human Health Assessment Scoping Document in Support of 

Registration Review for chlorfenapyr for a detailed discussion of the human health risk 

assessment. 

Hazard Characterization: 

• Chlorfenapyr has moderate acute toxicity via the oral route (Category II) and low acute 

toxicity via the dermal (Category III) and inhalation routes (Category III). It is a mild 

eye irritant, but it is not a dermal irritant or sensitizer. 

• The central nervous system is the primary target of chlorfenapyr in rats and mice. 

Dietary (Food and Water):

• For acute and non-cancer chronic exposures, the Agency is concerned when estimated 

dietary risk exceeds 100 percent of the population-adjusted dose (PAD). The acute and 

chronic dietary (food only) exposures to chlorfenapyr were below the Agency’s level of 

concern for the general U.S. population and all population subgroups examined. 

• The most recent risk assessment stated that there are no existing or proposed uses of 

chlorfenapyr which would result in contamination of drinking water. Accordingly, no 

estimated drinking water concentrations (EDWCs) were incorporated into the 2004 acute 

and chronic dietary exposure assessments. 

Residential:

• Chlorfenapyr is registered for residential (indoor and outdoor) and medical (indoor) uses. 

There are currently no registered residential uses that permit residential handlers, they are 

only allowed for application by certified professional applicators. 

• The Agency has determined that there is potential for post-application exposure to adults 

and children/toddlers from the residential termiticide and crack and crevice/mattress 

applications of chlorfenapyr. Based on a review of the registered labels, there is potential 

for dermal, incidental oral, (for young children) and inhalations exposure resulting from 
13 

this use. In the October 2001 occupational/residential exposure assessment, a residential 

post-application exposure assessment was conducted; however, only post-application 

inhalation exposure was assessed. Because highly conservative, worst case assumptions 

resulted in margins of exposure (MOEs) ≥ levels of concern (LOC = 100), risks did not 

exceed the Agency’s level of concern and are considered to be negligible. 

Occupational:

• The Agency has determined that occupational handlers are likely to be exposed to 

chlorfenapyr residues from the registered uses. In most cases, no chemical-specific data 

were available with which to assess potential exposure to pesticide handlers. Therefore, 

occupational handler assessments were based primarily on surrogate unit exposures from 

the Pesticide Handler’s Exposure Database (PHED) as presented in the PHED Surrogate 

Exposure Guide. The risk calculations were based on the maximum application rates and 

assuming maximum area treated per day or gallons handled. Handler’s exposure and risk 

were calculated at two levels of mitigation: baseline (long pants, a long-sleeved shirt, no 

chemical-resistant gloves, and no respirator) and personal protective equipment (baseline 

clothing with chemical-resistant gloves when necessary). 

• The most recent exposure assessment for pesticide handlers for the registered greenhouse 

use (fruiting vegetables) was conducted in March of 2003. Provided that commercial 

pesticide handlers used label prescribed personal protective equipment (PPE), all 

assessed MOEs were not of concern to the Agency (i.e., MOEs were ≥ LOC = 100) at the 

maximum label rate of 0.2 lb ai/A (or 13 fl oz/100 gallons). 

• A 1999 assessment was conducted for chlorfenapyr use on ornamental plantings in 

greenhouses, at a maximum application rate of 0.64 lb ai/A. No occupational handlers 

MOEs were of concern to the Agency at this rate. The current label for this use lists the 

maximum application rate as 0.32 lb ai/100 gallons. 

• Exposures and risks to handlers applying chlorfenapyr at a rate of 0.0469 lb ai/gal as a 

soil termiticide and crack and crevice spray were below the Agency’s level of concern 

(MOEs ≥ LOC = 100). 

• Occupational handler assessments have not been assessed for the following scenarios: 

o mixer/loader/applicator scenarios for aerosol can applications for all use sites 

o mixer/loader/applicator scenarios for high pressure spray application on non-edible 

greenhouse ornamentals at the current maximum label rate of 0.32 lb ai/100 gal. 

In addition to those scenarios that have not been assessed previously, several 

occupational handler scenarios may need to be reassessed if changes are made to the 

hazard assessment. 

• Occupational post-application exposure is expected from the foliar uses of chlorfenapyr 

in greenhouses. Occupational post-application exposure is not expected from the 

termiticide and crack and crevice use in residential sites, indoor medical, indoor outdoor 

commercial sites, or food/feed handling establishments.

• The most recent occupational post-application exposure assessment of chlorfenapyr was 

conducted in March of 2003 for activities associated with fruiting vegetables. In that 

assessment, the following post-application activities for fruiting vegetables were 
14 

assessed: hand harvest, pruning, staking, thinning, training, tying, scouting, and weeding. 

MOEs were not of concern to the Agency (i.e., MOEs were ≥ LOC = 100). 

• Past chlorfenapyr risk assessments rely in part on data from studies in which adult human 

subjects were intentionally exposed to a pesticide to determine their dermal and 

inhalation exposure. Many such studies, involving exposure to many different pesticides, 

comprise generic pesticide exposure databases such as the Pesticide Handlers Exposure 

Database (PHED) and the Agricultural Reentry Task Force (ARTF) Database. EPA has 

reviewed all the studies supporting these multi-pesticide generic exposure databases, and 

has found no clear and convincing evidence that the conduct of any of them was either 

fundamentally unethical or significantly deficient relative to the ethical standards 

prevailing at the time the research was conducted. All applicable requirements of EPA’s 

Rule for the Protection of Human Subjects of Research (40 CFR Part 26) have been 

satisfied, and there is no regulatory barrier to continued reliance on these studies. 

Aggregate:

• The 2003 risk assessment determined that because none of the use patterns for 

chlorfenapyr would result in contamination of drinking water or residential exposures, an 

aggregate risk assessment was not necessary. An aggregate risk assessment will need to 

be conducted once a revised residential post application assessment is available.

Incident Reports:

Ecological Incidents: 

• Approved uses of chlorfenapyr are largely limited to indoor environments with little 

potential for outdoor releases. There are no reported ecological incidents from the 

currently registered uses of chlorfenapyr.

Human Incidents: 

• The Incident Data System (IDS) identified two human health case reports attributable to 

chlorfenapyr reported to the IDS between 2002 and present. One incident involved a 

person who experienced occupational exposure to his eyes while at work. The patient 

immediately flushed his eyes and the itchiness went away within few hours. The other 

case involved a patient with a history of brain surgery who developed seizures after being 

at home for 20-30 minutes while the product (Phantom Termiticide) was applied. 

Six cases were reported in the NIOSH SENSOR database that involved the active 

ingredient chlorfenapyr (from 1998-2006). One incident involved a 52 year old female 

who experienced an asthma attack after a nearby office was sprayed with Phantom 

Termiticide. The only symptoms reported were respiratory effects. This case was ranked 

as low severity. 

Tolerances:

• There are no Codex or Canadian MRLs established for chlorfenapyr.

• The U.S. and Mexican tolerance definitions are harmonized for residues of chlorfenapyr 

in/on commodities in fruiting vegetable crop group 8.
15 

• There is an MRL of 0.5 ppm for cotton seed in Mexico which has no U.S. equivalent 

tolerance. 

• Mexico adopts U.S. tolerances and/or Codex MRLs for export purposes. 

Data Call-In Status:

• To date, no DCIs have been issued for chlorfenapyr. 

Labels: 

Product registration numbers are listed below and labels can be obtained from the Pesticide 

Product Label System (PPLS) website (<http://oaspub.epa.gov/pestlabl/ppls.home>). 

Active Chlorfenapyr Registrations 

Registration 

Number Name Company Name 

Percent 

Active 

Ingredient 

241-366 Chlorfenapyr Technical 241 – BASF Corporation 97.1 

241-374 Pylon Miticide-Insecticide 241 – BASF Corporation 21.4 

241-392 Phantom Termiticide-Insecticide 241 – BASF Corporation 21.45 

7969-285 Prescription Treatment Brand 

Phantom Pressurized Insecticide 7969 – BASF Corporation 0.5 

MS020023 Phantom Termiticide-Insecticide 241 – BASF Corporation 21.45