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Program Highlights

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  • Groups of Pesticides in Registration Review

  • Current as of September 30, 2013

    Overview of the Registration Review Program

    Registration review is replacing EPA's pesticide reregistration and tolerance reassessment programs as those programs are being completed. Unlike earlier review programs, registration review operates continuously, encompassing all registered pesticides.

    Through registration review, EPA is reviewing each registered pesticide every 15 years to determine whether it still meets the FIFRA standard for registration. In this way, the Agency is ensuring that all registered pesticides do not cause unreasonable risks to human health, workers, or the environment when used as directed on product labeling. The scope and depth of the Agency's reviews are tailored to the circumstances, so registration reviews are commensurate with the complexity of issues currently associated with each pesticide.

    By law, the Agency must complete the first 15-year cycle of registration review by October 1, 2022. To meet this requirement, EPA is opening 70 or more dockets annually continuing through 2017, so that almost all pesticides registered at the start of the program will have dockets opened by 2017. In fiscal year 2012, 744 pesticide cases comprising 1,165 active ingredients are scheduled for registration review. (These numbers include cases that were scheduled but were not required to go through registration review because there are no active registrations for these pesticides in the U.S.) Newly registered pesticides will be folded in each year. The Agency must complete the registration review of each new pesticide active ingredient within 15 years of its initial registration. See Registration Review Schedule for Beginning Reviews, 2012-2015.

    Current Status

    As of September 30, 2013,

    The Docket for each pesticide case beginning registration review includes a Preliminary Work Plan, which explains what the Agency knows about the pesticide and our thought process for determining the anticipated data and assessment needs. After considering public comment, the Agency issues a Final Work Plan for each case which responds to comments received, explains the Agency's risk assessment and data needs, and presents an expected time line for the registration review. See Chemical Search.

    Groups of Related Pesticides Beginning Registration Review

    In conducting the registration review program, EPA generally will review pesticides in chronological order according to their baseline dates; that is, older cases will be reviewed first. Within this structure, however, the Agency also plans to review certain related pesticides at the same time. Pesticide cases may be related by chemical class or structure, mode of action, use, or for other reasons.

    During reregistration, the Agency gained experience and efficiencies in simultaneously reviewing related pesticides in groups like the organophosphates, N-methyl carbamates, triazines, and chloroacetanilides, as well as the rodenticides and soil fumigants. Similarly, EPA expects to increase program efficiencies and promote other benefits by continuing the practice of grouping related pesticides during registration review. For example:

    The following groups of related pesticides have started registration review or are scheduled to begin registration review from 2012 to 2015.

    Organophosphates (OP) and N-methyl Carbamates

    EPA completed cumulative risk assessments and risk management decisions for the organophosphate (OP) pesticides in August 2006 and the N-methyl carbamate pesticides in September 2007. Further consideration is needed regarding these pesticides' effects on endangered species. In recent years, EPA and stakeholders have invested significant resources in gaining a better understanding of these classes of pesticides. Addressing endangered species effects early in registration review will ensure that this investment is not lost or eroded over time. The registration review of the OPs began in 2008, and the N-methyl carbamate review began in 2010.

    Pyrethroids, Pyrethrins and Synergists (PPS)

    During fiscal year 2008, EPA completed reregistration eligibility decisions (REDs) for the last individual pyrethroids, pyrethrins and synergists (PPS) that were subject to reregistration. Meanwhile, other PPS were not subject to reregistration; they are new active ingredients first registered after November 1, 1984. The PPS pesticides have similar uses and issues but have never before been considered together. Many have residential uses that may result in urban runoff, potentially contaminating surface water and sediment, and posing ecological risks. Most of these pesticides require endangered species risk assessments. Because the PPS pesticides may be used as alternatives for one another, it makes sense to consider them together and assess and manage their risks within a similar timeframe. EPA, therefore, is considering the PPS during registration review, starting in FY 2010 to FY 2012.

    Sulfonylureas (SU)

    To increase efficiencies, EPA also began reviewing the sulfonylurea herbicides (SUs) as a group during registration review, starting in FY 2011. SUs are herbicides that control weeds through inhibition of the enzyme acetolactate synthase. SUs are used as pre- and post-emergent herbicides to control a variety of weeds on cereal grains, pasture and rangeland, industrial sites, and turf grass.

    Many of the constituent herbicides of this chemical class were first registered in the 1980s or later and so have not undergone reregistration. Consequently, the oldest group of these chemicals began registration review in 2011, and two subsequent groups of more recently registered SUs are scheduled to have dockets opened in 2012 and 2013.

    Registration Review of the sulfonylureas will include an evaluation of the need for endangered species risk assessments and an examination of the potential for adverse reproductive effects of sulfonylureas on off-site non-target plant species, such as may result from spray drift.

    Neonicotinoids (NN)

    The neonicotinoids are a class of insecticides with a common mode of action that affects the central nervous system of insects, causing paralysis and death. All of the neonicotinoids were registered after 1984 and were not subject to reregistration. Some uncertainties have been identified since their initial registration regarding the potential environmental fate and effects of neonicotinoid pesticides, particularly as they relate to pollinators. Data suggest that neonicotinic residues can accumulate in pollen and nectar of treated plants and may represent a potential exposure to pollinators. Adverse effects data as well as beekill incidents have also been reported, highlighting the potential direct and/or indirect effects of neonicotinic pesticides. Therefore, among other refinements to ecological risk assessment during registration review, the Agency will consider potential effects of the neonicotinoids to honeybees and other pollinating insects.

    The registration review docket for imidacloprid opened in December 2008, and the docket for nithiazine opened in March 2009. To better ensure a “level playing field” for the neonicotinoid class as a whole, and to best take advantage of new research as it becomes available, the Agency has moved the docket openings for the remaining neonicotinoids on the registration review schedule (acetamiprid, clothianidin, dinotefuran, thiacloprid and thiamethoxam) to FY 2012.

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    Fumigants (FUM)

    Fumigants share the characteristics of being volatile and mobile in the environment, so methods to assess them are somewhat novel. Soil fumigants were determined to be eligible for reregistration in 2008 and several other other fumigant pesticides completed reregistration a few years earlier. While EPA is implementing risk mitigation decisions for the soil fumigants, new research is underway to address current data gaps and refine understanding of factors that affect how fumigants move in the environment. New methods and technologies for fumigation are emerging. EPA decided to move the fumigants forward in registration review from 2017 to 2013 so the Agency will be able to consider new data and new technologies sooner, as well as determine whether mitigation included in its decisions is effectively addressing risks as EPA believes it will. EPA will also include other fumigants that were not part of the reregistration review of these pesticides.

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    Triazines (TR)

    EPA decided to review all pesticides in the triazines group within the same time frame and to move these pesticides ahead in the registration review schedule so that dockets for all will open in FY 2013. EPA initiated a reevaluation of the triazine pesticide atrazine in fall 2009. Given the availability of new scientific information as well as the documented presence of atrazine in both drinking water sources and other bodies of water, EPA has determined it appropriate to consider the new research and to ensure that the Agency’s regulatory decisions about atrazine protect health and the environment. EPA’s reevaluation process is based on transparency and sound science, including independent scientific peer review. The current atrazine reevaluation will help address aspects of the atrazine registration review which is scheduled to begin in 2013. As a result, the current reevaluation should reduce the scope and resources needed to complete the atrazine registration review.

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    Imidazolinones (IM)

    Imidazolinones are low-dose, high-potency herbicides that work by inhibition of the acetolactate synthase (ALS) enzyme in plants. Their mode of action is similar to that of the sulfonylurea (SU) family of herbicides, for which registration review dockets will open between FY 2011 and FY 2013. In addition, imazapyr was the only one of the imidazolinones to be subject to reregistration; registration review will provide the first opportunity to consider the six herbicides in this family in a common timeframe, starting in FY 2014.

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    Isothiazolinones (IS)

    Isothiazolinones (or isothiazolones) are a group of compounds known for biocidal activity that are registered with EPA as antimicrobial agents and have similar uses and use patterns. Some of the isothiazolinones have conventional pesticide uses, as well. EPA has adjusted the registration review schedule for the isothiazolinones so that all of the uses of this family of pesticides can be considered in a common timeframe, starting in FY 2014.

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    Pyridines (PY)

    Pyridine herbicides, which are used to control a number of broadleaf plants, have primarily been identified in previous risk assessments as posing a potential risk to non-target plants. In particular, some herbicides in this family appear in reported incidents to have persisted in manure or compost later applied to planted fields. As with the imidazolinones, only a portion of the pyridine family was subject to reregistration, and registration review affords the Agency the opportunity to consider all the herbicides in this family in a common timeframe, starting in FY 2014.

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