Docket Number EPA-HQ-OPP-2011-0482 www.regulations.gov



## Ancymidol

Interim Registration Review Decision

Case Number 3017

Approved 

### by:

Date: 

## August 2014

## p~**~** Richard P. Keigwin, Jr.

Director

Pesticide Re-evaluation Division2



### Contents

I. INTRODUCTION

................................ ................................ ................................ ...................... 3

II. SCIENTIFIC ASSESSMENTS

................................ ................................ ................................ ... 4

A. Human Health Assessment

................................ ................................ ................................ ............ 4

B. Environmental Assessment

................................ ................................ ................................ ............ 4

1. Environmental Exposure

................................ ................................ ................................ ............ 4

2. Environmental Risk Characterization

................................ ................................ ........................ 5

3. Endangered Species Assessment

................................ ................................ ............................... 5

C. Endocrine Disruptor Screening Program

................................ ................................ ...................... 5

III. INTERIM REGISTRATION REVIEW DECISION

................................ ............................... 6

IV. NEXT STEPS

................................ ................................ ................................ ........................... 63

I. INTRODUCTION

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

Revie w Decision for ancymidol

, pursuant to 40 CFR § 155.5 6 and § 155.58. A registration review decision is the Agency’s determination that 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 deems appropriate, a n i nterim registration review decision before completing a registration review

. Among other things, t he 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 the new risk assessment

, and completing the registr ation review

.

FIFRA, as amended by the Food Quality Protection Act (FQPA) of 1996, mandated the continuous review of existing pesticides. 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 and reduce risk evolves and as

p olicies and practices change, all registered pesticides continue to meet the statutory standard of no

unreasonable adverse effect to human health or the environment

. Through the registration review program, the Agency periodically reevaluates pesticides to make sure that as these change s occur, products in the marketplace can be safely used. Information on this program is provided at : http://www.epa.gov/oppsrrd1/registration_review/

. In 2006, the Agency implemented the Registration Review program pursuant to FIFRA Section 3(g) and will review each registered pesticide every 15 years to determine whether it continues to meet the FIFRA standard for registration

.

Ancymidol is a pyrimidine plant growth regulator registered for treating container

- grown herbaceous plants, ornamental woody shrubs, and bedding plants grown in greenhouses and in outdoor plant

b edding areas for commercial production. It is also registered for use as a seed treatment for ornamental plants, and treated seeds are used to start plants. T reatment with ancymidol is intended to induce a more compact growth form by suppressing growth b etween nodes, resulting in bushier plants and shrubs. Use of anc y midol is limited to nursery grown ornamentals; no food, feed, or residential uses are registered for ancymidol. EPA completed a Reregistration Eligibility Decision (RED) for ancymidol in Ju ne 1995.

Pursuant to 40 CFR § 155.50, the Agency formally initiated registration review for ancymidol ( c ase 3017) in June 2011. The following timeline highlights significant events that have occurred during the registration review of ancymidol:

 June 2 011

- Publication of the Ancymidol Preliminary Work Plan (PWP) for a 60

- day comment period. Th e PWP was accompanied by the scoping document and the problem

formulation

.

 December 2011

- Publication of the Final Work Plan (FWP) and EPA’s response to the single public comment received. The FWP did not modify the anticipated risk assessment, data needs, or registration review timeline de scribed in the PWP . However, the FWP noted that a recent evaluation of environmental exposures m ight alter the Agency’s planned4

ecological risk assessment and anticipated data requirements for ancymidol by eliminating

the need for a data call

- in

.

 January 2013

- EPA revisited the planned registration review risk assessment s and supporting d ata requirements and determined that sufficient information w as available to conduct qualitative risk assessment s to support an interim registration review decision, pursuant to 40 CFR § 155.53(b). This decision shortened the registration review timeline

described in the FWP.

 March 2 013

- EPA published qualitative human health and environmental fate and effects risk assessments for ancymidol in the ancymidol registration review docket for a 60

- day comment period

. No comments were received on the documents: Ancymidol. Registration Review Preliminary Risk Assessment ( Human Health

) or EFED Preliminary Risk Assessment to Classify Registered Ancymidol Uses as De Minimus Risk to Listed/Non

- listed Species and “No Effects”

Determinations.

 June 4, 2014

– EPA publis hed the Ancymidol Proposed Interim Registration Review Decision in the Federal Register (79 FR 32284; FRL

- 9911

- 16) for a 60

- day comment period. EPA received comments from the Center for Biological Diversity; these comments supported the Agency’s

Interim R egistration Review Decision.

For further information on the registration review of ancymidol, see EPA’s public docket (EPA

HQ

- OPP

- 2011

- 0482) at www.regulations.gov

.

II. S CIENTIFIC ASSESSMENT S

A summary of the Agency’s preliminary human health and e nvironmental risk assessments

, published on March 12, 2013

, is presented below . The preliminary risk assessments and additional supporting documents are located in the registration review docket, EPA

- HQ

- OPP

- 2011

- 0482.

A. Human Health Assessment

The Agency conducted a qualitative human health risk assessment for ancymidol

. Ancymidol has no registered food/feed or residential uses and existing use patterns are not expected to contaminate surface or ground water; thus, dietary and residential exposure assessment s w ere not conducted. EPA evaluated occupational handler risk only.

EPA conducted a qualitative occupational handler assessment for a ncymidol based on its limited use, minimal potential for inhalation and dermal exposure, and general lack of evidence of significant toxicity to humans. T he Agency believes, based on available information, that use of ancymidol should not pose a dermal or inhalation risk to workers. For details, see the March 5, 2013

memo, Ancymidol. Registration Review Preliminary Risk Assessment.

B. Environmental Assessment

1. Environmental Exposure

Available data on the use of ancymidol in nurseries and greenhouses show that less than 20 pounds of active ingredient were used per year nationwide for the years 1999, 2002, 2004, and 2006. Most of the5

use of ancymidol occurs indoors, but a small amount may be used to treat plants in containers placed outdoors on nursery plant beds, or as a greenhouse seed treatment for ornamentals later planted

out doors. As a plant growth regulator, ancymidol acts systemically and is taken up by the plant when applied. Ancymidol is assumed to be absorbed very rapidly by the plant because the plants may be

watered as soon as one hour after application , according to label directions, without a n apparent reduction in efficacy. Ancymidol is extremely dilute when applied

, and the use is spread across

thousands of faciliti es throughout the United States

. As a result, environmental exposure is negligible. For details, see the November 28, 2011 memo, Equivalent outdoor per

- acre application rates for ancymidol used

on container

- grown greenhouse transplants

.

2. Environmental Risk Characterization

EPA c onducted a qualitative environmental fate and effects assessment for ancymidol. EPA

consider ed potential ancymidol exposure to non

- target organisms, available information on the toxicity of ancymidol

, and the registered uses of ancymidol in th e qual i t a tive assessment.

The available toxicity data for ancymidol show low toxicity to freshwater and terrestrial organisms.

While the A gency does not currently have terrestrial plant toxicity data, effects to terrestrial plants

are no t reasonably expected to occur given the currently registered uses of ancymidol . When EPA compared conservative assumptions of environmental exposure from application of ancymidol products at the maximum use rates with available toxicity data, the resulting values were below the Agency’s level of concern. Therefore, g iven the type s and extent of the registered use s of ancymidol, the low toxicity shown by existing studies , the small quantity used and the diffuse nature of use, the A gency believes th at registered use s of ancymidol should not adversely affect non

- target organisms. For details of the environmental risk assessment, see the February 25, 2013 memo, EFED Preliminary Risk Assessment to Classify Registered Ancymidol Uses as De Minimus Risk t o Listed/Non

listed Species and “No Effects” Determination

.

3. Endangered Species Assessment

There is no reasonable expectation for any registered use of ancymidol to cause direct or indirect adverse effects to threatened and endangered species. No adverse modification of critical habitat is expected to occur from use of ancymidol. This is becau se of the type s and extent of use, the low toxicity shown by existing studies, the highly diffuse nature of the use site, and the extremely low annual usage

. EPA has made a “no effect” determination under the Endangered Species Act (ESA) for all listed spe cies and designated critical habitat for such species and 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. For details, see the February 25, 2 013 Preliminary Risk

Assessment cited above.

C. E ndocrine Disruptor Screening Program

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.” Under FFDCA section 408(p), the Agency must screen all pesticide chemicals. Between October 2009 and November 2010, EPA issued test orders/data6

call

- ins for the first group of 67 chemicals and published a second list of chemicals proposed for

order issuance in the future. Ancymidol 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 wil l issue future EDSP orders/data call

- ins for registration review chemicals, including ancymidol. 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 te st 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 ancymidol. Before completing this Registration Review, the Agency will make an EDSP FFDCA section 408(p) determination.

I II. INTERIM REGISTRATION REVIEW DECISION

In accordance with 40 CFR Sections 155.56 and 155.58, the Agency is issuing this I nterim Registration Review D ecision

. Except for the EDSP component of the ancymidol registration review case, the Agency has determined the following: (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. In addition, EPA does not expect ancymidol to have direct or indirect adverse effects to non

- listed and listed species or to designated critical habitat

. As such, EPA has made a “no effect” determination

under the Endangered Species Act (ESA) for all listed species and designated critical habitat for such species.

IV. NEXT STEPS

EPA will make a final registration review decision for ancymidol after an EDSP FFDCA section 408(p) determination has been made.