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Macleaya Extract – Table of Contents 

I. Introduction ..........................................................................................................................3 

A. General Background ....................................................................................................4 

II. Scientific Assessments ........................................................................................................4 

A. Human Health Assessment..........................................................................................4 

B. Environmental Assessment .........................................................................................5 

C. Endangered Species Assessment .................................................................................5 

D. Use and Usage Information .........................................................................................6 

E. Endocrine Disruptor Screening Program ..................................................................6 

III. Interim Registration Review Decision .............................................................................6 

IV. Next Steps and Timeline ...................................................................................................7 
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I. Introduction 

This document is the Environmental Protection Agency’s (EPA or the Agency) Interim 

Registration Review Decision for macleaya extract and it discusses public comments received 

concerning the Proposed Interim Registration Review Decision. It is being issued pursuant to 40 

CFR sections 155.56 and 155.58. A registration review decision is the Agency’s determination 

whether a pesticide meets, or does not meet, the standard for registration in the Federal 

Insecticide, Fungicide, and Rodenticide Act (FIFRA). The Agency may issue, when it 

determines it to be appropriate, an interim registration review decision before completing a 

registration review. Among other things, the interim registration review decision may (1) require 

new risk mitigation measures; (2) impose interim risk mitigation measures; (3) identify data or 

information required to complete the review; and (4) include schedules for submitting the 

required data, conducting new risk assessments or revising preliminary assessments, and 

completing the registration review. 

 During the 60-day public comment period for the macleaya extract Proposed Interim 

Registration Review Decision, which opened on July 23, 2014, and closed on September 22, 

2014, the Agency received one comment. The comment was submitted by the Center for 

Biological Diversity (CBD) and CBD commented that it that agreed with the Agency’s finding 

for this chemical case regarding endangered species. The public comment in its entirety is 

located in the docket, EPA-HQ-OPP-2011-0172. 

Pursuant to 40 CFR Section 155.50, EPA formally initiated registration review for 

macleaya extract (case 7024). The following highlights significant events that have occurred 

during the registration review of macleaya extract: 

 March 30, 2011 – Publication of the Macleaya Extract Summary Document for a 60-day 

public comment period. The Summary Document included the preliminary work plan 

(PWP) and was accompanied by the scoping document and problem formulation. 

 August 17, 2011 - Final Work Plan (FWP) for macleaya extract was signed -- two public 

comments were received during the 60-day comment period for the Macleaya Extract 

Summary Document. However, the comments did not affect the risk assessments to be 

performed, the anticipated data requirements, or the projected registration review timeline 

and thus, the FWP did not modify the Summary Document. 

 A Data Call-In (DCI) was issued in June 2012 requiring submission of certain toxicity 

studies. The required studies were subsequently waived by the Hazard and Science 

Policy Council (HASPOC) in 2013 based on the Weight of Evidence (WOE) approach 

considering the following: 1) the limited exposure profile of macleaya extract; 2) there 

are no registered food uses of macleaya extract at this time; 3) no exposure to macleaya 

extract is expected through drinking water; 4) the use of an oral point of departure (POD) 

results in dermal margins of exposure (MOEs) that do not exceed the Agency’s level of 

concern (LOC) (MOEs >300 are below the Agency’s LOC) for highest occupational 

exposures (i.e., MOEs are greater than 3,600 and 440 for handlers and post-application 

workers, respectively); 5) the use of an oral POD results in inhalation MOEs that do not 

exceed the Agency’s level of concern for workers (MOE greater than 13,000); and 6) the 
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low vapor pressure and physical chemical properties of sanguinarine, a major component 

of macleaya extract. 

 In June 2014, EPA completed a preliminary human health risk assessment for macleaya 

extract using available data and data from surrogate chemicals, sanguinaria extract and 

sanguinarine chloride. The Agency also completed a preliminary ecological risk 

assessment in 2014. No public comments were received concerning these assessments 

during a 60-day public comment period. 

 June 26, 2014 – Proposed Interim Registration Review Decision for macleaya extract was 

signed -- one public comment was received during the 60-day comment period for the 

document. However, as discussed above, the comment did not affect the proposed 

decision. 

Additional information about macleaya extract, including this Interim Registration 

Review Decision can be found in EPA’s public docket, EPA-HQ-OPP-2011-0172, accessed at 

www.regulations.gov. 

A. General Background

Macleaya extract is a plant extract of Macleaya cordata, and is registered for use only in 

enclosed commercial greenhouses, as an ornamental plant fungicide for the control of foliar 

fungal diseases. There are no registered food or feed uses of macleaya extract. The only end use 

formulation of macleaya extract is a soluble/concentrate liquid. It is applied as a foliar spray by 

backpack or high pressure sprayer and has no residential uses. Macleaya extract was first 

registered in 2002 and therefore was not subject to reregistration. 

II. Scientific Assessments

A summary of the Agency’s human health risk assessment and ecological risk 

assessment, Macleaya Extract: Preliminary Risk Assessment for Registration Review (June 12, 

2014) and Registration Review: Preliminary Ecological Risk Assessment and Endangered 

Species Effects Determination for Macleaya Extract (June 11, 2014), is presented below. For the 

actual assessments, see the macleaya extract public docket (EPA-HQ-OPP-2011-0172) accessed 

at www.regulations.gov. 

A. Human Health Assessment 

 Hazard Characterization 

The toxicological database is considered adequate for characterizing hazard and assessing 

risk from macleaya extract. A point of departure (POD) was identified for occupational 

exposure only. 

Dietary Exposure Assessment 

There are no registered food/feed uses and existing use patterns are not expected to 

contaminate surface or ground water; thus, a dietary exposure assessment was not conducted. 
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 Food Tolerances 

There are no U.S. tolerances established for macleaya extract because macleaya extract is 

not registered for any food/feed uses. 

 Residential and Occupational Exposure 

Macleaya extract has no registered residential uses; residential exposures are, therefore, 

not expected. The only end use formulation of macleaya extract is a liquid concentrate and it is 

applied as a foliar spray by backpack or high pressure sprayer in enclosed commercial 

greenhouses. Although exposure may occur during occupational handling and post-application 

activities, a screening level assessment based on maximum application rates and baseline attire1

indicated no risk of concern via dermal and inhalation routes of exposure. Furthermore, the 

current label requires all handlers to wear personal protective equipment (i.e., chemical-resistant 

gloves in addition to baseline attire) and includes a restricted entry interval of 12 hours, which is 

considered to be adequately protective. Therefore, EPA concludes that risk from occupational 

exposure to macleaya extract should not be of concern. (Macleaya Extract: Preliminary Risk 

Assessment for Registration Review, June 12, 2014)

B. Environmental Assessment 

The Agency previously concluded in a 1999 review that the enclosed commercial 

greenhouse use for macleaya extract does not provide a feasible route of exposure to non-target 

organisms, and therefore would not result in any significant exposure or risk to non-target 

organisms. As the use pattern has not changed since the previous review in 1999, the Agency 

concluded that a quantitative ecological risk assessment and a drinking water exposure 

assessment were not necessary for the registration review of macleaya extract. 

C. Endangered Species Assessment 

There is no reasonable expectation for registered use of macleaya extract in enclosed 

commercial greenhouses to cause direct or indirect adverse effects to threatened and endangered 

species. No adverse modification of critical habitat is expected from the use of macleaya extract. 

Based on the indoor-only use pattern for macleaya extract and the lack of a complete exposure 

pathway, EPA has made a “no effects” determination under the Endangered Species Act (ESA) 

for all listed species as well as a “no habitat modification” determination for all designated 

critical habitats for the currently registered uses of macleaya extract. The Agency has therefore 

concluded that consultation with the Fish and Wildlife Service and the National Marine Fisheries 

Service under ESA section 7(a)(2) is not required. EPA anticipates conducting no further 

analysis of potential risks to endangered or threatened species, unless data or information are 

obtained during the Registration Review process that would indicate such an assessment would 

be needed to inform the Agency’s decision. (Registration Review: Preliminary Ecological Risk 

Assessment and Endangered Species Effects Determination for Macleaya Extract, June 11, 

2014) 

 

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 Baseline attire refers to a basic level of personal protective equipment worn during handling activities, and is 

defined as a single layer of clothing consisting of a long sleeved shirt, long pants, shoes plus socks, no protective 

gloves, and no respirator. 
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D. Use and Usage Information 

Use of macleaya extract was not reported in the National Agricultural Statistics Service 

(NASS) nursery and floriculture usage surveys conducted in 2002, 2004, or 2007. In addition, 

usage was not reported in the 2006-2008 California Department of Pesticide Regulation pesticide 

usage reports. Macleaya extract was not reported in these surveys indicating that the usage of 

this chemical is likely to be low. 

Macleaya extract can be used in organic production of greenhouse ornamentals2

. There 

are no known resistance concerns for the macleaya extract end use product. Please see the 

BEAD Chemical Profile for Registration Review: Macleaya Extract in the registration review 

docket for more details.

E. Endocrine Disruptor Screening Program 

EPA has developed the Endocrine Disruptor Screening Program 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.” Under FFDCA section 408(p), the 

Agency must screen all pesticide chemicals. Between October 2009 and November 2010, EPA 

issued test orders/data call-ins for the first group of 67 chemicals and published a second list of 

chemicals proposed for order issuance in the future. Macleaya extract was not among the group 

of 58 pesticide active ingredients on the initial list nor is it proposed on the second list of 

chemicals to be screened under the EDSP. Accordingly, as part of registration review, EPA will 

issue future EDSP orders/data call-ins for registration review chemicals, including macleaya 

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

67 chemicals, future chemical lists proposed for screening, the test guidelines and the Tier 1 

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

 In the interim, EPA is making no human health or environmental safety findings 

associated with the EDSP screening of macleaya extract. Before completing this Registration 

Review, the Agency will make an EDSP FFDCA section 408(p) determination. 

III. Interim Registration Review Decision

In accordance with 40 CFR Sections 155.56 and 155.58, the Agency is issuing this 

Interim Registration Review Decision. Except for the EDSP component of the macleaya extract 

registration review case, the Agency has made the following Interim Registration Review 

Decision: (1) no additional data are required at this time; and (2) no changes to the affected 

registrations or their labeling are needed at this time. EPA has not identified any risks of concern 

to human health. EPA has determined that use of macleaya extract in commercial greenhouses 

should not result in any significant exposure or risk to non-target organisms. As such, EPA 

 

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 Copping, L.G. and Duke, S.O. 2007. Natural products that have been used commercially as crop protection agents. 

Pest Management Science 63:524-554. 
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concludes “no effect” for listed species and no adverse modification of designated critical habitat 

for all currently registered uses of macleaya extract. 

IV. Next Steps and Timeline 

A final decision on the macleaya extract registration review case will occur after an 

EDSP FFDCA section 408(p) determination has been made. 

EPA created the following estimated timeline for the completion of the macleaya extract 

Interim Registration Review Decision. 

Registration Review for Macleaya Extract – Timeline

Activities Estimated Date 

Opening the Docket 

Open Docket and Public Comment Period March 2011 – Completed 

Close Public Comment Period May 2011 – Completed 

Case Development 

Final Work Plan August 2011 – Completed 

Issue DCI June 2012 – Completed 

Open Public Comment Period for Draft Risk Assessments July 2014 – Completed 

Close Public Comment Period September 2014 – Completed 

Registration Review Decision 

Open Public Comment Period for Proposed Interim 

Registration Review Decision 

July 2014 – Completed 

Close Public Comment Period September 2014 – Completed 

Interim Registration Review Decision and Begin PostDecision Follow-up3

December 2014 – Completed 

Total (years) 3.75 

 

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 A final decision on the macleaya extract registration review case, in accordance with 40 CFR Section155.158, will 

occur after an EDSP FFDCA section 408(p) determination has been made.