By Timothy D. Backstrom and James V. Aidala
On December 18, 2019, the Office of Pesticide Programs (OPP) of the U.S. Environmental Protection Agency (EPA) issued for comment a Proposed Interim Decision (PID) in the ongoing registration review process for each of the three registered triazine herbicides: atrazine, propazine, and simazine. EPA will allow 60 days for comment on each of these triazine PIDs, but the specific comment deadline will only be established after EPA has published notice concerning the proposed interim decisions in the Federal Register. EPA can utilize an “interim registration review decision” under 40 C.F.R. Section 155.56 whenever it is not yet ready to complete the registration review process, but EPA has nonetheless completed sufficient review to determine that new or interim risk mitigation measures are needed or that additional data or information should be submitted to complete the review. For each of the three triazine herbicides, EPA is proposing to impose specific risk mitigation measures for particular registered uses to mitigate potential health and environmental risks. For each triazine herbicide, EPA is not yet ready to make a final registration review decision because EPA has not made findings in the Endocrine Disruptor Screening Program (EDSP) or an effects determination under the Endangered Species Act (ESA). Several key factors that will affect the final registration review decision for each of the triazine herbicides are discussed below.
Common Factors for Triazine Risk Assessment
There are several common factors to consider with regard to the triazines risk assessment. These include:
- Atrazine, propazine, and simazine are all included in the chlorotriazine chemical class. EPA has determined that these three herbicides, along with three specific chlorinated metabolites, share a common mechanism of toxicity, so human health risks from all of these substances are being assessed by EPA together through one cumulative triazine risk assessment. The contribution of each product to aggregate human risk differs because of somewhat dissimilar use patterns. The combining of risks resulting from use of each triazine means, however, that it may be necessary for EPA to coordinate the ultimate registration review decisions for the three active ingredients.
- As part of the ecological risk assessment for each triazine herbicide, EPA plans to make an effects determination for potentially vulnerable species under the ESA, which in turn will determine whether it is necessary for EPA to consult with the Fish and Wildlife Service or the National Marine Fisheries Service (the Services) concerning potential impacts of each active ingredient and relevant metabolites on endangered or threatened species. Atrazine, propazine, and simazine are all included in a stipulated settlement between the parties in Center for Biological Diversity et al. v. EPA et al. No. 3:11 cv 0293 (N.D. Cal.), and EPA agreed in that stipulated settlement to set August 14, 2021, as the deadline for EPA to make a nationwide effects determination for each active ingredient, and to request any required consultation with the Services, under ESA Section 7(a)(2).
- EPA states that the predominant human health effect of concern for all three of the triazine herbicides and their chlorinated metabolites is potential suppression of the luteinizing hormone (LH) surge, which is considered to be both a neuroendocrine and a developmental effect. Atrazine and simazine were both included on List 1 for screening testing under the EDSP required by the Food Quality Protection Act (FQPA) amendments. All of the required Tier 1 screening assays for each of these substances are complete and have been evaluated by EPA, but EPA has not yet made human health or environmental findings under the EDSP. The EDSP screening testing has not been completed yet for propazine.
Risk Mitigation Measures
Each PID proposes specific risk mitigation measures intended to address potential human and environmental risks identified by the EPA risk assessments.
For atrazine, the PID includes the following measures to mitigate aggregate human risk:
- Reduce the permissible application rates for use of granular and liquid formulations on residential turf.
- Require additional personal protective equipment (PPE) and engineering controls for certain uses.
- Restrict aerial applications to liquid formulations only.
- Limit backpack sprayer applications to landscape turf to spot treatment only.
- Prohibit pressurized handgun application to certain commodities.
To mitigate ecological risks, the atrazine PID proposes to require various spray drift reduction measures, to add a non-target advisory statement to labeling, and to adopt a nationwide stewardship program.
For propazine, the PID proposes to cancel the greenhouse use to mitigate aggregate human risk. Ecological risks would be mitigated by proposing to require various spray drift reduction measures and by adding a non-target advisory statement to labeling.
For simazine, the PID includes the following measures to mitigate aggregate human risk:
- Cancel simazine use on residential turf.
- Require additional PPE and engineering controls for certain uses.
- Limit pressurized handgun applications to certain commodities to spot treatment only.
Ecological risks would be mitigated by proposing to require various spray drift reduction measures and by adding a non-target advisory statement to labeling.
In each of the PIDs for the triazine herbicides, EPA has focused its efforts on adopting mitigation measures which should be efficacious in reducing human and ecological risks without materially impairing the availability of the products in question for key agricultural uses. In some instances, the PID documents explicitly state that the product registrants have agreed to proposed changes. An EPA Pesticide Program Update dated December 19, 2019, that discusses the interim decision for atrazine includes statements of support from several grower groups.
By Timothy D. Backstrom
On December 5, 2019, the U.S. Environmental Protection Agency (EPA) Office of Pesticide Programs (OPP) announced the availability of a revised interim registration review decision for use of sodium cyanide in the M-44 predator control device. The M-44 device is a restricted use pesticide (RUP) and may be used only by certified applicators in compliance with specific mandatory restrictions set forth on the label. Although the registration review process for sodium cyanide remains pending, EPA has decided to issue an interim decision for the M-44 device now to adopt new label restrictions intended to mitigate potential risks. The revised interim decision adopts two new restrictions and also modifies certain existing restrictions, which EPA states "will reduce the potential for unintended impacts on humans, pets, and other non-target animals.”
The M-44 predator control device uses a spring-loaded ejector to fire a capsule containing a single lethal capsule of sodium cyanide. The M-44 is used by livestock producers to control predators (primarily coyotes) that kill sheep, goats, and cattle. Registrations for the M-44 device are currently held by the U.S. Department of Agriculture, and by five individual States (South Dakota, Texas, Montana, Wyoming, and New Mexico) where livestock predation has been a particular problem.
New or revised restrictions that will be incorporated in the approved labeling for the M-44 device include:
- Requiring a 600-foot buffer zone around residences where an M-44 cannot be used (except for a cooperating landowner who has given written permission).
- Requiring that the applicator notify occupants of all residences within a 0.5 mile radius (by face-to-face communication, person-to-person telephone communication, door hanger, or certified mail) prior to an M-44 placement.
- Increasing from 50 feet to 300 feet the distance from designated public paths and roads where M-44 use is prohibited.
- Requiring two elevated warning signs placed 15 feet from the M-44 device and facing the most likely directions of approach, instead of one elevated sign placed 25 feet from the device.
Livestock producers and State departments of agriculture contend that the M-44 device is essential to limit economic losses resulting from predation, which reportedly amount to hundreds of millions of dollars annually. In contrast, wildlife advocates have strongly opposed any continued use of the M-44 device. In 2017, WildEarth Guardians and the Center for Biological Diversity petitioned EPA to suspend and cancel all registrations for M-44 capsules, but EPA concluded that the petition did not contain substantial new information and denied the petition in 2018. Although the new and modified label restrictions adopted by EPA in the interim decision for the M-44 device are not likely to satisfy opponents, these changes should nonetheless reduce the likelihood that humans, pets, or other non-target species will be exposed to the M-44 capsules or the toxin they contain.
By Lisa M. Campbell and Timothy D. Backstrom
On August 7, 2019, the League of United Latin American Citizens, Pesticide Action Network North America, Natural Resources Defense Council, and other petitioners (Petitioners) filed a new petition in the Ninth Circuit Court of Appeals seeking judicial review of United States Environmental Protection Agency (EPA) orders denying their request that EPA revoke all tolerances and cancel all registrations for chlorpyrifos. On August 8, 2019, New York, California, Hawaii, Maryland, Vermont, Washington, Massachusetts, and the District of Columbia (States) also filed a new petition for judicial review concerning the refusal of EPA to ban chlorpyrifos. The Petitioners and the States seek judicial review of the July 18, 2019, final order by EPA dismissing all objections to the initial decision by EPA to retain tolerances and registrations for chlorpyrifos, and of EPA’s March 29, 2017, order that initially denied a 2007 petition to revoke all tolerances and cancel all registrations for chlorpyrifos.
The Petitioners and the States also seek consolidation of their newly filed petitions for judicial review with currently pending chlorpyrifos litigation in LULAC, et al. v. Wheeler, et al. As part of rehearing in the LULAC case, the Ninth Circuit vacated a prior decision that ordered EPA to cancel chlorpyrifos registrations, and instead issued a writ of mandamus requiring EPA to respond to objections to the 2017 denial order within 90 days. EPA then issued the July 18, 2019, order denying all objections, along with a motion on July 19, 2019, to dismiss the LULAC case as moot. EPA seeks dismissal of LULAC because it contends that the 2017 initial order was never itself reviewable, and EPA has now done everything that the writ of mandamus required. The Petitioners oppose the motion to dismiss because it would require the Court to take a position on a jurisdictional issue which they contend was not decided during rehearing. The Petitioners and the States also argue that dismissal would be unnecessary and inefficient, requiring the challenging parties to reconstitute the record for review compiled in LULAC.
Petitioners also note that the Ninth Circuit retained jurisdiction when it issued mandamus in LULAC, and they request that their combined challenge to the EPA decision to retain the existing tolerances and registrations for chlorpyrifos be heard by the Court en banc as well.
The latest petitions for judicial review of EPA’s 2019 decision to retain all tolerances and registrations for chlorpyrifos pending registration review were anticipated by all parties, and all parties agree that the procedural requisites for a judicial determination concerning the legality of EPA’s final decision to deny the 2007 administrative petition have now been satisfied. The Petitioners and the States will likely argue that prior scientific determinations by EPA, including EPA analysis of epidemiology studies that purport to establish a link between exposure to chlorpyrifos and adverse neurodevelopmental effects in children, require that EPA proceed to revoke all tolerances and cancel all registrations for chlorpyrifos, while EPA will likely argue that difficult scientific issues concerning chlorpyrifos remain unresolved and should be addressed by EPA as part of the pending registration review for chlorpyrifos.
In addition to the dispute about combining the new petitions for review with the LULAC case, an interesting element of the latest filing by the Petitioners is that they attempt to bootstrap en banc review of the 2019 order in which EPA finally denied the administrative petition to revoke tolerances and cancel registrations for chlorpyrifos. En banc review for an initial hearing (as opposed to en banc rehearing in a previously decided case) is allowed by the applicable appellate rules, but such review is disfavored and would be highly unusual. Petitioners argue that it is warranted here because the en banc panel in the rehearing in the LULAC case reserved jurisdiction. Given the motion by EPA to dismiss the LULAC case as moot, it can be presumed that EPA is likely to oppose this vicarious argument for en banc judicial review. EPA can argue that the only reason the en banc panel retained jurisdiction was to assure that EPA would timely comply with the writ of mandamus that required EPA to rule on the objections within 90 days.
For further information on the long history of litigation concerning the petition to ban chlorpyrifos, please review our prior blog entries.
By Lisa M. Campbell, Timothy D. Backstrom, and James V. Aidala
On August 2, 2019, the U.S. Environmental Protection Agency (EPA) Office of Pesticide Programs (OPP) announced that it has decided to reduce the Food Quality Protection Act (FQPA) safety factor for infants and children for pyrethroids from its current value of 3X to a new value of 1X. This decision is based on a July 1, 2019, OPP report entitled “USEPA Office of Pesticide Programs’ Re-evaluation of the FQPA Safety Factor for Pyrethroids: Updated Literature and CAPHRA Program Data Review.” Risk assessments incorporating the new lower FQPA safety factor for pyrethroids will be utilized in developing proposed registration review decisions for these compounds, and EPA has stated it will be taking public comment on the OPP report reducing the FQPA safety factor for pyrethroids after EPA publishes a notice of availability for the proposed registration review decisions.
Pyrethroids are a group of insecticides that includes natural pyrethrins (found in chrysanthemums) and more than 30 synthetic compounds with similar structure and activity. EPA has determined that it is appropriate to establish one FQPA safety factor for all pyrethroid active ingredients because these compounds all have the same mode of action and similar patterns of toxicity. Pyrethroid insecticides are widely used in and around residential structures, on pets, in treated clothing, for mosquito control, and in various agricultural applications. EPA indicates that although pyrethroids have relatively low mammalian toxicity, EPA believes that the principal concern for human risk assessment is a potential to cause acute neurotoxic effects.
The FQPA safety factor is intended to account for “potential pre- and post-natal toxicity and completeness of data with respect to exposure and toxicity to infants and children.” The FQPA safety factor is set by statute at a default value of 10X, but EPA may select a lower value for this safety factor if EPA determines based on “reliable data” that such a lower value will be safe for infants and children. This determination necessarily depends on EPA’s assessment of the quality of the data that address the susceptibility to adverse effects of the pesticide of infants and children. Based on current EPA guidance, OPP evaluates the need for the default FQPA safety factor of 10X in two components: a safety factor of about 3X assigned to pharmacodynamic (PD) differences and a safety factor of about 3X assigned to pharmacokinetic (PK) differences. PD differences refer to the sequence of events at the molecular or cellular level leading to a toxic response to a substance, while PK differences refer to absorption, distribution, metabolism, and excretion of the substance.
EPA previously evaluated the adequacy of the database concerning risks to infants and children posed by pyrethroid active ingredients in 2011. At that time, EPA decided that there were sufficient data concerning the mechanism for potential neurotoxic effects of pyrethroids to allow EPA to reduce the factor for PD differences to 1X, but EPA retained the 3X factor for PK differences because EPA believed that the available pharmacokinetic data for pyrethroids was not sufficient for EPA to conclude that infants and children would not confront a greater risk of neurotoxic outcomes. After EPA made the 2011 determinations, the Council for the Advancement of Pyrethroid Human Risk Assessment (CAPHRA) conducted a variety of additional research to address whether children are more sensitive to the neurotoxic effects of pyrethroid exposure, and this research assessed both PD and PK differences. CAPHRA submitted a peer-reviewed physiologically based pharmacokinetic (PbPk) model for pyrethroids to EPA in 2018. After reviewing the new CAPHRA data and the current public literature for pyrethroids, EPA has now concluded that the factor for PD differences should be maintained at 1X, but the factor for PK differences should be reduced from 3X to 1X. Collectively, these determinations mean that EPA has concluded that there are reliable data to support a determination that infants and children are not more susceptible to the neurotoxic effects of pyrethroids than adults, so there is no need to retain either the default FQPA safety factor of 10X or the previous FQPA safety factor used for pyrethroids of 3X.
The adoption by EPA of a new FQPA safety factor of 1X for all pyrethroid active ingredients will likely facilitate retention of existing use patterns and use directions for a large number of pyrethroid insecticides that are commonly used in and around human residences and workplaces.
From a larger perspective, the process by which EPA evaluated and selected a proposed FQPA safety factor for pyrethroids may be seen as typical for most pesticides or classes of pesticides. The selection of a FQPA safety factor for a particular pesticide usually is based on review of available animal data, including PD and PK data, to determine whether there is any basis for concluding that infants and children may be more susceptible to adverse effects of that pesticide than adults. Where EPA decides that the animal data addressing this question are insufficient, affected registrants and other proponents of registration can consult with EPA concerning studies that will address the uncertainties. Depending on the outcome of such studies, EPA may be able to conclude that there is a scientific basis for a partial or complete reduction of the default FQPA safety factor.
Compared to this typical evaluation process, the recent decision by EPA to retain the default FQPA safety factor for all organophosphate (OP) active ingredients, which was based on EPA’s interpretation of neurodevelopmental effects reported at low exposure levels (below the threshold for acetylcholinesterase inhibition) in epidemiology studies for chlorpyrifos, may be seen as an aberration. EPA’s decision to rely on epidemiology studies that may be susceptible to methodological biases, and the decision to utilize epidemiology studies for chlorpyrifos to set the FQPA safety factors for all OP pesticides, have both been controversial.
EPA’s recent decision to retain the current tolerances and registrations for chlorpyrifos was based in significant part on EPA’s interpretation of a PbPk model for chlorpyrifos previously submitted by DowAgro (now Corteva), which mitigated to some degree EPA’s retention of the default FQPA safety factor for chlorpyrifos. Corteva may submit further data addressing PD and PK differences for chlorpyrifos, and EPA has also stated that it intends to review some new animal studies for chlopyrifos, which purport to show neurodevelopmental effects at low exposure levels. Perhaps these data will allow EPA to establish a point of departure (POD) for chlorpyrifos risk assessment without any need for a further excursion into the unfamiliar risk assessment territory represented by EPA’s use of epidemiology data for chlorpyrifos.
By Lisa M. Campbell, Timothy D. Backstrom, James V. Aidala, and Lisa R. Burchi
On July 18, 2019, the U.S. Environmental Protection Agency (EPA) issued a pre-publication version of a Federal Register notice announcing a final order denying the Pesticide Action Network North America’s (PANNA) and the Natural Resources Defense Council’s (NRDC) 2007 Petition requesting that EPA revoke all tolerances and cancel all registrations for chlorpyrifos (Order). This Order constitutes final Agency action denying all of the Petitioners’ objections to EPA’s previous refusal to revoke the tolerances for chlorpyrifos. This Order also constitutes final administrative action concerning all parts of the 2007 Petition that were not previously addressed by EPA. Given the previous extensive chlorpyrifos litigation, this latest action by EPA will likely lead to further litigation challenging EPA’s decision to allow continued use of chlorpyrifos under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and the Federal Food, Drug, and Cosmetic Act (FFDCA).
The FIFRA registrations and related tolerances for chlorpyrifos have a complicated regulatory and legal history, as discussed in previous blogs available here.
EPA’s new Order denies objections made by PANNA and NRDC under the FFDCA to EPA’s March 29, 2017, order denying the request by PANNA and NRDC that EPA revoke all tolerances for chlorpyrifos and cancel all chlorpyrifos product registrations. In the Order, EPA begins by summarizing its prior responses to the 2007 Petition, in which EPA denied each of ten claims raised in support of the Petitioners’ request that EPA revoke all chlorpyrifos tolerances and cancel all chlorpyrifos registrations. The ten claims are:
- EPA has ignored genetic evidence of vulnerable populations.
- EPA has delayed a decision regarding endocrine disrupting effects.
- EPA has ignored data regarding cancer risks.
- EPA’s 2006 cumulative risk assessment (CRA) for the organophosphates misrepresented risks and failed to apply the Food Quality Protection Act (FQPA) 10X safety factor.
- EPA over-relied on registrant data.
- EPA has failed to address properly the exporting hazard in foreign countries from chlorpyrifos.
- EPA has failed to incorporate quantitatively data demonstrating long-lasting effects from early life exposure to chlorpyrifos in children.
- EPA has disregarded data demonstrating that there is no evidence of a safe level of exposure during pre-birth and early life stages.
- EPA has failed to cite or incorporate quantitatively studies and clinical reports suggesting potential adverse effects below 10 percent cholinesterase inhibition.
- EPA has failed to incorporate inhalation routes of exposure.
EPA’s Order next focuses on the June 2017 objections to the March 29, 2017, Denial Order that were filed by several public interest groups and states. The three main objections, and EPA’s response, are as follows:
- Claims Regarding the Legal Standard for Reviewing Petitions to Revoke: Objectors assert that EPA’s Denial Order applied the wrong legal standard. Objectors assert that neither “scientific uncertainty” nor the October 2022 deadline for registration review under FIFRA Section 3(g), nor the widespread agricultural use of chlorpyrifos, provide a basis for denying petitions to revoke. Objectors claim that EPA has unlawfully left chlorpyrifos tolerances in place without making the safety finding required by the FFDCA.
- EPA Response: In its Order, EPA denies the objections related to Petitioners’ claims regarding neurodevelopmental toxicity, stating that the objections and the underlying Petition are not supported by valid, complete, and reliable evidence sufficient to meet the Petitioners’ burden under the FFDCA, as set forth in EPA’s implementing regulations. Specifically, EPA states that Objectors have not met their regulatory burden to provide “reasonable grounds” for revocation, including an assertion of facts to justify the modification or revocation of the tolerance (40 C.F.R. § 180.32(b)) or the initial evidentiary burden for persons seeking revocation to come forward with sufficient evidence to show that pesticide tolerances to be modified or revoked are not safe. After summarizing its review of available epidemiologic data, including feedback from the 2012 and 2016 FIFRA Scientific Advisory Panel (SAP) meetings, EPA states that “the epidemiologic studies are central to the Petitioner’s claims regarding neurodevelopmental effects, yet the Petitioners and Objectors rely only on summaries in publications to present their case. Petitioners have not presented the raw data from the epidemiology studies for consideration of their claims.” EPA “concludes that the information yet presented by Petitioners is not sufficiently valid, complete, and reliable to support abandoning the use of AChE inhibition as the critical effect for regulatory purposes under the FFDCA section 408” and also that Petitioners have “failed to meet their initial burden of providing sufficiently valid, complete, and reliable evidence that neurodevelopmental effects may be occurring at levels below EPA’s current regulatory standard and no information submitted with the objections addresses this shortcoming of the Petition.”
- Objections Asserting that EPA Has Found Chlorpyrifos to Be Unsafe: Objectors assert that EPA has previously found that chlorpyrifos tolerances are unsafe and has not disavowed those findings. Specifically, they claim that EPA has found that chlorpyrifos results in unsafe drinking water exposures and results in adverse neurodevelopmental effects to children and that EPA must therefore revoke the tolerances.
- EPA Response: EPA denies making any regulatory findings that chlorpyrifos tolerances are not safe, stating that its statements in its 2015 proposed tolerance revocation was not a final action. EPA states: “Proposed rules are just that -- proposals; they do not bind federal agencies. Indeed, EPA made clear it was issuing the proposal because of the court order, without having resolved many of the issues critical to EPA’s FFDCA determination and without having fully considered comments previously submitted to the Agency.” Regarding those objections related to drinking water, EPA states that since the Petition did not identify drinking water exposure as a basis for seeking tolerance revocation, the Objectors cannot now raise that concern as a basis for challenging EPA’s denial of the Petition. EPA also states: “The mere fact that EPA is considering the potential impact of chlorpyrifos exposures in drinking water in the Agency’s FIFRA section 3(g) registration review does not somehow provide Petitioners and Objectors with a vehicle for introducing that topic in the objections process on the Petition denial.” EPA instead will continue its FIFRA Section 3(g) registration review and complete its evaluation of drinking water exposures to chlorpyrifos, and address these issues in its upcoming registration review decision.
- Objections Asserting that the Denial Order Failed to Respond to Significant Concerns Raised in Comments: Objectors argue that EPA’s Denial Order committed a procedural error by failing to address significant concerns raised in the comments on EPA’s 2014 risk assessment and 2015 proposed revocation that EPA’s assessment fails to protect children. In particular, the Objectors focus on concerns raised in comments asserting that (1) EPA’s use of 10 percemt cholinesterase as a regulatory standard is not protective for effects to children’s developing brains; (2) EPA has not properly accounted for effects from inhalation of chlorpyrifos from spray drift and volatilization; and (3) EPA inappropriately used the Corteva physiologically based pharmacokinetic (PBPK) model to reduce inter- and intra-species safety factors because the model is ethically and scientifically deficient.
- EPA Response: EPA denies the objections claiming procedural error, stating it “has no obligation to respond to rulemaking comments in denying the Petition or responding to objections, both of which are adjudicatory actions that are not part of the rulemaking process. EPA also restated its prior response to the Petition that the “objections fail to meet burden of presenting evidence sufficiently valid, complete and reliable to demonstrate that chlorpyrifos results in neurodevelopmental effects that render its tolerances not safe.” EPA further “believes it is lawful and appropriate for it to consider federally enforceable chlorpyrifos product labeling restrictions in assessing the extent of bystander risk from spray drift under both the FFDCA and FIFRA.”
This latest EPA assessment appears to be more finely crafted than the earlier March 2017 response to the tolerance revocation Petition. EPA explains that it does not consider the epidemiology studies cited by the Petitioners to be persuasive sufficiently to change EPA’s fundamental approach to assessing chlorpyrifos risks. EPA notes that its current risk assessment utilizes the default 10X safety factor for infants and children specified by the FQPA, so any argument that it has not utilized this safety factor is moot. At the same time, EPA maintains that the epidemiology studies do not justify changing EPA’s point of departure for risk assessment, which remains the threshold for 10 percent acetylcholinesterase (AChE) inhibition. EPA states that there are significant problems with using the epidemiology studies for risk assessment, including lack of access to the underlying data, the absence of any known mechanism for neurodevelopmental effects below the threshold for AChE inhibition, and a lack of scientific consensus on a method for choosing an alternate point of departure based on the epidemiology studies. This interpretation of the epidemiology studies for chlorpyrifos will remain controversial and these studies will continue to be cited by those who seek to eliminate chlorpyrifos use.
EPA has also taken a position that the burden is on the Petitioners to support a petition to revoke tolerances with reliable data. What is less clear is “how much” evidence EPA considers sufficient to meet the threshold for tolerance revocation. Meanwhile, EPA will defer its assessment of possible neurodevelopmental effects of chlorpyrifos below the threshold for AChE inhibition pending completion of the registration review for chlorpyrifos. The deadline for EPA to complete registration review is October 1, 2022, although EPA states that it intends to expedite this process and to issue a proposed registration review decision by October 2020.
EPA also has included in its decision an intriguing discussion of some new animal studies for chlorpyrifos that purport to show low-level neurodevelopmental effects from chlorpyrifos. The California Department of Pesticide Regulation relied substantially on these new studies when it designated chlorpyrifos as a Toxic Air Contaminant. If these new chlorpyrifos studies are deemed credible, they could supplant efforts to use the chlorpyrifos epidemiology data in risk assessments and allow EPA to establish a new point of departure for chlorpyrifos that is not based on AChE inhibition. Rather than disregarding these new data, which were not submitted in support of the tolerance revocation Petition, EPA says affirmatively that it intends to review them in the pending registration review.
By Lisa M. Campbell and Barbara Christianson
On June 26, 2019, the U.S. Environmental Protection Agency (EPA) announced it was extending the comment deadline on its Proposed Interim Registration Review Decision (PID) for glyphosate acid and its various salt forms. 84 Fed. Reg. 30112. EPA states that it is extending the comment deadline “after receiving public comments requesting additional time to review the Glyphosate Proposed Interim Registration Review Decision and supporting materials.”
The deadline to submit comments was extended from July 5, 2019, to September 3, 2019. The public can submit comments on EPA’s proposed decision at www.regulations.gov in Docket Number EPA-HQ-OPP-2009-0361.
More information on glyphosate issues is available on our blog.
By Lisa M. Campbell, Lisa R. Burchi, and James V. Aidala
On May 6, 2019, the U.S. Environmental Protection Agency (EPA) announced it was releasing its Proposed Interim Registration Review Decision (PID) for glyphosate acid and its various salt forms. 84 Fed. Reg. 19782. In the PID, EPA states that it “did not identify any human health risks from exposure to any use of glyphosate” but did identify “potential risk to mammals and birds” within the application area or areas near the application area and “potential risk to terrestrial and aquatic plants from off-site spray drift, consistent with glyphosate’s use as a herbicide.” Even with these potential risks, the PID states that “EPA concludes that the benefits outweigh the potential ecological risks when glyphosate is used according to label directions” and proposes certain risk mitigation strategies, including:
- “To reduce off-site spray drift to non-target organisms, the EPA is proposing certain spray drift management measures” with specific spray drift mitigation language to be included on all glyphosate product labels for products applied by liquid spray application;
- “To preserve glyphosate as a viable tool for growers and combat weed resistance, the EPA is … proposing that herbicide resistance management language be added to all glyphosate labels” and to require measures “for the pesticide registrants to provide growers and users with detailed information and recommendations to slow the development and spread of herbicide resistant weeds”;
- Inclusion on labels of a non-target organism advisory statement to alert users of potential impact to non-target organisms; and
- “EPA is also proposing certain labeling clean-up/consistency efforts to bring all glyphosate labels up to modern standards.”
EPA states that these measures were discussed with glyphosate registrants, who do not oppose the proposed risk mitigation measures outlined in the PID.
The public can submit comments on EPA’s proposed decision at www.regulations.gov in Docket Number EPA-HQ-OPP-2009-0361. Public comments are due by July 5, 2019. In addition to the PID, EPA is also posting to the glyphosate docket EPA’s response to comments on glyphosate’s usage and benefits (dated April 18, 2019), EPA’s response to comments on the human health risk assessment (dated April 23, 2018), and EPA’s response to comments on the preliminary ecological risk assessment (dated November 21, 2018).
This PID was issued shortly after the Agency for Toxic Substances and Disease Registry’s announcement on April 8, 2019, of the opening of a docket on the draft toxicological profile for glyphosate. 84 Fed. Reg. 13922. ATSDR seeks comments and additional information or reports on studies about the health effects of glyphosate for review and potential inclusion in the profile. Comments are due by July 8, 2019.
EPA’s PID and related documents, along with ATSDR’s draft profile and the peer review which will follow, can be expected to become part of the larger debate about the potential risks of glyphosate. In 2017, EPA evaluated the carcinogenic risk of glyphosate, and released its draft human health and ecological risk assessments. See our December 19, 2017, blog item "EPA Releases Draft Human Health and Ecological Risk Assessments for Glyphosate for Public Comment" for more information.
EPA’s PID is interesting not only for the conclusions EPA reached following its review of data submitted by registrants in response to a data call-in (DCI) and following the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) Scientific Advisory Panel’s (SAP) meeting to consider and review scientific issues related to EPA’s evaluation of the carcinogenic potential of glyphosate, but for the issues that remain to be addressed. Notably, EPA states that it has not considered the petition filed on September 27, 2018, to reduce glyphosate’s tolerance because the petition was filed after the comment period for the human health and ecological risk assessments closed. Instead, EPA plans to post the petition in the glyphosate docket and address the petition concurrently with the development of the Interim Registration Review Decision.
In addition, EPA has not in the PID or related documents addressed issues regarding its Endangered Species Act (ESA) assessment or its Endocrine Disruptor Screening Program (EDSP) activities. EPA states it intends to complete an assessment of risk to ESA-listed species prior to completing its final registration review decision for glyphosate, and that it also will make an EDSP determination under Federal Food, Drug, and Cosmetic Act (FFDCA) Section 408(p) before completing its registration review. EPA also notes that it continues to evaluate risks to pollinators, and that if it determines “that additional pollinator exposure and effects data are necessary to help make a final registration review decision for glyphosate, then the EPA will issue a DCI to obtain these data.” Although there are significant areas that remain to be resolved, EPA issued the PID “so that it can (1) move forward with aspects of the registration review case that are complete and (2) implement interim risk mitigation.”
More information on glyphosate issues is available on our blog.
By James V. Aidala
On December 15, 2017, the U.S. Environmental Protection Agency (EPA) announced its release of preliminary ecological and human health risk assessments for three neonicotinoid insecticides: clothianidin, thiamethoxam, and dinotefuran, as well as a preliminary ecological risk assessment for imidacloprid, assessing risks to birds, mammals, non-target insects, and plants. The assessments are available in the dockets linked below:
EPA also released new cotton and citrus benefits assessments for foliar applications of the neonicotinoids as well as its response to public comments on the 2014 Benefits of Neonicotinoid Seed Treatment to Soybean Production. These are available in Docket No. EPA-HQ-OPP-2014-0737.
For all of the dockets listed above, EPA states that it is particularly interested in public comment on the benefits for cotton and citrus, since previous assessments identified potential risks to pollinators. Further, EPA states that “early input from the public will be helpful in developing possible mitigation options that may be needed to address risks to bees. Among the benefits identified, the neonicotinoids were found to be critical for management of Asian citrus psyllid -- which causes citrus greening, a devastating pest for citrus growers, and for control of plant bugs and stink bugs in cotton.” The comment period will begin when the Federal Register notice is published and will be open for 60 days. EPA states that it plans to release the final pollinator risk assessments and proposed interim decisions for these chemicals in mid-2018.
These documents EPA has added to the dockets linked above add to a trove of continued EPA assessments of the neonicotinoid compounds. In January 2016, EPA assessed the risks to pollinators and concluded that the seed treatment uses are generally not of concern, but that there are possible risks of importance in citrus and cotton production. This is why this recent batch of documents, including the benefits assessments of the neonicotinoid products in citrus and cotton production, along with the long-awaited response to comments to EPA’s earlier benefit assessment of the soybean use, has been anticipated for some time. In summary, the benefits assessment for both cotton and citrus indicate significant benefits for these uses. And regarding the earlier benefits assessment of soybeans, EPA now concludes that it underestimated the benefits of the soybean uses generally and in particular has concluded significant benefits in some regions from soybean seed treatments.
With EPA now concluding these uses have significant benefits, there may be some need for risk mitigation of certain use patterns, but generally the estimated benefits will offset and preclude the imposition of more general label restrictions for these crops. For example, the benefits assessment for the citrus uses states flatly that the continued sustainability of the citrus crop requires continued use of the neonicotinoid products (to control the insect that is the vector for citrus greening disease).
Regarding other formulations and risk to organisms other than honeybees, the documents do identify some possible adverse impacts on non-target aquatic insects, birds, and possibly some aquatic invertebrates. These initial findings will likely continue to fuel the debate about the impacts of neonicotinoid use. Registrants will likely submit significant amounts of rebuttal data to further refine these risk estimates and currently do not anticipate significant additional label restrictions as a result, especially since EPA has concluded these products have more significant economic benefits which will be part of any risk-benefit considerations as EPA moves forward.
More information on neonicotinoid issues is available on our blog under key word neonicotinoids.
By Lisa M. Campbell, Jason E. Johnston, M.S., and James V. Aidala
On May 25, 2017, the U.S. Environmental Protection Agency (EPA) announced the release of ecological risk assessments for four neonicotinoid active ingredients for public comment as well as the Registration Review Update for Four Neonicotinoid Insecticides (Update). 82 Fed. Reg. 24113. The ecological risk assessments are:
EPA states that public comments “could address, among other things, the Agency’s risk assessment methodology and assumptions applied to its draft risk assessments, such as its methodology for estimating colony-level risk to bees from exposure to bee bread.” Comments on the three ecological risk assessments are due by July 24, 2017.
The main focus of the Update document is EPA’s efforts to harmonize the risk assessment and management of the four neonicotinoids during registration review. EPA has identified additional pollinator exposure data and pollinator toxicity data needs; registrants have committed to producing the needed data, and most of the data will be submitted in 2017. EPA plans to produce final pollinator risk assessments for both agricultural and non-agricultural uses in 2018. Release of non-pollinator risk assessments (i.e., aquatic organisms, terrestrial mammals, and birds) is planned for 2017. Human health risk assessments are also scheduled to be issued in 2017. EPA has stated that mitigating risk from the uses of all neonicotinoids may be considered for all four compounds at the same time to ensure consistent risk management and to prevent unnecessary shifts in usage between the compounds without a reduction in risk. EPA intends to release final pollinator assessments and proposed interim decisions for registration review for all four neonicotinoids in 2018.
From the EPA website, the following general statement summarizes what EPA has found so far:
- The assessments for clothianidin, thiamethoxam, and dinotefuran, similar to the preliminary pollinator assessment for imidacloprid showed: most approved uses do not pose significant risks to bee colonies. However, spray applications to a few crops, such as cucumbers, berries, and cotton, may pose risks to bees that come in direct contact with residue.
To some degree, it is reassuring that widespread adoption of the neonicotinoid products appears not to be an overwhelming or altogether unanticipated risk to pollinators. For insecticides, that foliar spray applications could be harmful is not good news, as any direct contact of an insect (bees) and insecticides usually is not good for the health of the insect.
Another point some may find reassuring is that EPA has not found seed treatment with neonicotinoid products to be of significant risk. This is ironic to some degree, since one of the fundamental assumptions not long ago among many beekeepers was that the seed treatment products were a singular and significant cause of the increase in colony decline and loss.
EPA’s description of the registration review status of these products also indicates that a great volume of additional data concerning possible pollinator risks is due to arrive over the next six to 18 months. Obviously, the results of these additional studies will fundamentally inform the EPA risk assessment conclusions. At the same time, one legacy of the Obama Administration in this space, the development of state Manage Pollinator Protection Plans (MP3), also will be impacted by what EPA discovers from this volume of soon-to-arrive data.
Until then, and until the new political leadership of the agency indicates any direction on pollinator issues, it is unclear whether the pollinator issue will remain one of the priority issues for program attention, or be folded into the general timeline and normal course or registration review over the next few years.
By Lisa M. Campbell and Lisa R. Burchi
On Thursday, April 30, 2015, the U.S. Environmental Protection Agency (EPA) issued interim guidance that it intends to clarify its toxicology data requirements for antimicrobial pesticides used on food contact surfaces. In addition, EPA issued a letter to antimicrobial registrants that EPA states is intended “to summarize how the Agency has been implementing 158W with respect to existing registered antimicrobial pesticides, as well as new and pending antimicrobial pesticide applications.”
The interim guidance is intended to satisfy a condition of the March 2, 2015, settlement agreement between EPA and the American Chemistry Council (ACC), which followed ACC’s July 2013 initiation of a legal challenge to the antimicrobial data requirements (subpart 158W of Title 40 of the Code of Federal Regulations) in the U.S. Court of Appeals in the District of Columbia. The settlement agreement is discussed here.
In the settlement, EPA agreed to issue, within 60 days of the Agreement becoming final, an interim guidance document explaining EPA’s interpretation of the 200 parts per billion (ppb) residue level above which additional toxicology testing would be required for indirect food uses.
The interim guidance states with regard to the 200 ppb standard:
No later than September 2, 2017, the Agency will propose a correction to 40 CFR Part 158W to make the rule’s language as it pertains to the 200 ppb level established in 40 C.F.R. § 158.2230(d) consistent with the U.S. Food and Drug Administration’s use of that same level. The proposal will be to clarify that the 200 ppb level established in the rule is based on total estimated daily dietary intake, and is not based on the amount of residue present on only a single commodity. The Agency is providing this interim guidance to registrants that the referenced 200 ppb level is based on total estimated daily dietary intake rather than on the amount of residue present on only a single commodity.
EPA states that this interpretation is consistent with the U.S. Food and Drug Administration’s (FDA) policy. In general, if pesticide residues in food resulting from use on food contact surfaces are 200 ppb or less, EPA requires certain toxicology data. If residues are greater than 200 ppb, additional data may be required, depending on other conditions such as test results.
Also in the settlement, EPA agreed to propose, within four months of the Agreement becoming final, a guidance document entitled Antimicrobial Pesticide Use Site Index (USI), and provide a 30-day comment period. The USI guidance will provide descriptions of direct food uses, indirect foods uses, and nonfood uses. The letter states the following regarding its development of the USI guidance:
The Agency is developing a guidance document called the Antimicrobial Pesticide Use Site Index (USI) that will serve as a compilation of existing use sites and will identify how each use site fits within the twelve use patterns established in 158W. The guidance document will serve to assist prospective registrants with the application requirements by making it easier for them to identify which data are necessary to register their product(s).
EPA’s letter also discusses the following regarding existing and pending antimicrobial pesticide applications:
- EPA may find it necessary, “in the context of, but not limited to, the requirements in 158W,” to call in data as each active ingredient is evaluated under the Registration Review program. EPA does not intend to conduct this generic evaluation for new products or applications to amend existing products that are covered in Pesticide Registration Improvement Extension Act (PRIA3) fee category Table 9 -- Antimicrobial Division -- New Products and Amendments.
- During early implementation of the 158W requirements, EPA recognizes that not all new applications will have all the newly-required data. EPA may thus find it appropriate to issue Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) Section 3(c)(7) conditional registrations and set a deadline for the submission of the required data.
- Any application submitted after July 8, 2013 (the effective date of the 158W requirements) must contain the required data or an adequate justification for any data requirements not submitted. On the issue of timing, applicants should explain why any data are not yet submitted and when the data can be submitted. Failure to submit required data or provide an adequate justification will result in EPA rejecting the application as incomplete under the 45/90 day preliminary technical screen under the Pesticide Registration Improvement Act (PRIA).
The settlement agreement and additional documents are available at http://www2.epa.gov/pesticide-registration/epa-data-requirements-registration-antimicrobial-pesticides-part-158w#interim and www.regulations.gov in docket EPA-HQ-OPP-2008-0110. More information on antimicrobial policies and guidance is available here.