Close This Window

Posted 18 March 09

Sierra Club's Imidacloprid comments to EPA

The EPA was asking for public comments by March 17, 2009 for input on its review of the insect pesticide Imidacloprid linked to the massive die offs of honey bees in the U.S. in recent years. Here are Sierra Club's comments, written by Genetic Engineering Action Team member Neil Carman, Ph.D.

March 17, 2009

James J. Jones, Acting Administrator
Office of Pesticide Programs (OPP)
Regulatory Public Docket (7502P)
U.S. Environmental Protection Agency
1200 Pennsylvania Ave., NW
Washington, DC 20460-0001
Submitted via Federal eRulemaking Portal

RE: Docket ID Number EPA-HQ-OPP-2008-0844 - Comments on registration review of Imidacloprid¨

Dear Office of Pesticide Programs Acting Administrator Jones:

The Sierra Club strongly supports EPA’s pesticide registration review for Imidacloprid, a chloro-nicotinyl insecticide based on scientific concerns that it is “very highly toxic to nontarget insects” like honey bees as EPA notes in the Ecological Risk Assessment document. Evidence supports that Imidacloprid has potent sublethal effects like disorientation and lethality in honey bees. However, EPA needs to move more expeditiously than the schedule proposed in the FR Notice of completion by 2014.

EPA needs to require Imidacloprid’s manufacturer to submit multi-generation studies of chronic toxicity.

Multi-generational studies of Imidacloprid toxicity must be thoroughly investigated by the EPA to adult honey bees and all stages of development. The EPA needs to require Imidacloprid’s manufacturer to submit multi-generational studies of chronic toxicity investigating not only at the impact of Imidacloprid exposure on adult honey bees, but also its effects on honey bee brood development and survival. EPA should check to find out if the results of multi-generational studies have already been conducted in Europe, and, if such studies have been conducted, the EPA needs to obtain copies of published data in peer-reviewed journals and any other pertinent information available at European governmental agencies and other organizations that may have conducted their own studies and trials.  The EPA must likewise incorporate into its risk assessment information concerning Imidacloprid levels in the pollen and nectar of plants that receive systemic Imidacloprid treatment as well as in hive materials. This information is needed to determine the extent of bees’ total exposure to Imidacloprid, which has been ignored by EPA and the manufacturer.

EPA needs to investigate translocated Imidacloprid in plants and water exudates used by foraging bees.

EPA needs to thoroughly investigate the likely presence of Imidacloprid in translocated plant liquids. Translocated neonicotinoids that foraging honey bees may be drinking if the pesticides are present in the water exudates on the plant leaves need to be fully investigated as another source of contamination. Translocation of liquids is a well known and long studied plant physiological phenomenon that is even documented in most agricultural crops. However, the manufacturer of Imidacloprid may not have conducted any studies of the presence of Imidacloprid being translocated and found in plant water exudates. If resourceful honey fees became thirsty during their foraging trips such as hot summer days especially in the middle time periods at peak temperatures, honey bees may learn to look for water resources on the plant leaves and other organs as they search for pollen and nectar. Translocation can bring pesticides like Imidacloprid from the soils and seeds up into the plant and exuded onto leaves without little or minimal metabolism of Imidacloprid taking place. Metabolites of Imidacloprid may be present as well.

EPA needs to take faster action on suspending the registration for Imidacloprid to protect honey bees.

Sierra Club’s letter to EPA dated July 30, 2008 (copy in Docket EPA-HQ-OPP-2008-0844) recommended that EPA consider temporarily suspending the registration for Imidacloprid due to reasonable concerns and scientific evidence it was causing or significantly contributing to harming honey bees. EPA needs to address an interim ban or restrict its use in the United States and its territories pending the outcome of the Ecological Risk Assessment. Concerns about Imidacloprid expressed in the July 30, 2008 Sierra Club letter to OPP are re-emphasized in these comments. EPA needs to consider a list of options of temporarily suspending the registration for Imidacloprid and how it might be implemented. As of March 17, 2009, we are close to entering the beginning of this year’s growing season and no meaningful EPA action has been taken to protect honey bees in the US from the current disastrous CCD situation.

EPA needs to have a 2-3 year field trial conducted where Imidacloprid use is temporarily suspended.

If EPA does not find sufficient available evidence to warrant temporarily suspending the registration for Imidacloprid, EPA could work with USDA-APHIS, state agriculture agencies and the manufacturer to locate an area in the U.S. for a two-three year field trial where a temporary ban on Imidacloprid use could be conducted to determine if local honey bees recover after observing decimated honey bee colonies. The manufacturer of Imidacloprid needs to conduct these field trials. The area might need some type of geographical isolation to ensure foraging honey bees are not flying beyond the field trial area for pollen and nectar that could be contaminated with Imidacloprid and other pesticides from other agricultural areas.

Limitations of such a field trial include the challenges of existing residues of Imidacloprid and metabolites persisting in the soils and unsprouted seeds in the ground acting as local reservoirs for pesticides they were treated with. Field trials would also need cooperation from local honey bees keepers to document if the CCD phenomenon was still occurring in the area.

EPA needs laboratory clinical feeding trials conducted on Imidacloprid fed to adult honey bees and brood.

Video footage taken by French researchers showed how quickly honey bees reacted to low concentrations of Imidacloprid applied in their drinking water and food. French scientists found that Imidacloprid was almost instantly lethal to individual honey bees at remarkably low concentrations in the low parts per billion range. EPA needs to require the manufacturer of Imidacloprid to conduct such laboratory clinical feeding trials and videotape the feeding of adult honey bees and feeding to the developmental stages in addition.

Laboratory clinical feeding trials need to test different low concentration levels of Imidacloprid down to the 1.0 parts per trillion (ppt) level or until No Adverse Effects are detectable on the adult honey bees and the brood. Testing down to a concentration of only 1.0 parts per billion (ppb) may be insufficient to observe a No Adverse Effects threshold in adult honey bees and brood has been reached. If a threshold exists for No Adverse Effects, it needs to be well documented and replicated through a series of lab clinical trials instead of anecdotally suggesting the No Adverse Effects threshold is 5-10 ppb or 1 ppb.

The laboratory clinical feeding trials may need to conducted by independent scientists since the manufacturer of Imidacloprid has a significant financial stake and conflict of interest in not finding a problem with Imidacloprid at low concentrations. The EPA needs to ensure that whether the manufacturer or independent scientists conduct the laboratory clinical feeding trials, the results are subjected to thorough peer-review and videotaping may help to support the results.

The EPA needs to be sure that the Imidacloprid used in the laboratory clinical feeding trials is the same formulation and chemical grades sold to farmers rather than using a different formulation and chemical grade for the lab tests. A concern is that weaker formulations of Imidacloprid could be used in lab clinical trials.  The EPA needs to double check the formulations of Imidacloprid used in all studies under review.

EPA’s review schedule for Imidacloprid needs to be shortened from 2014.

EPA has a projected schedule for Imidacloprid’s review of 6 years (2008-2014) while the problem right now is that Imidacloprid may be causing or contributing to huge losses of critical honey bee colonies nationwide. EPA needs to find creative ways to shorten the review time frame or it may be too late to save honey bee colonies by 2014 and serious crop losses may be too devastated to recover combined with major drought and climate change challenges occurring throughout large agricultural sections of the US.

Has EPA considered ways to use more independent academic scientists to shorten the review process by 2-3 years? The EPA needs to recruit teams of independent academic scientists to conduct research and involve them in the peer-review process.

EPA needs to seriously consider organizing an international conference in the US to help address scientific issues by July-August 2009 on the Ecological Risk Assessment of Imidacloprid. At a minimum, EPA could organize a two-three day conference in Washington, D.C. with independent scientists in the U.S. and Europe to present their latest research evidence and preliminary findings that may not be published for months or several years. If funds are short to allow foreign scientists to attend, EPA could arrange for their lectures by video-conferencing or over the internet.

EPA could organize a second conference in 2010 for 1-2 days in Washington, D.C. to assess the latest research findings and what, if any, additional research needs to be conducted.

EPA use of extensive non-peer-reviewed pesticide industry data for Imidacloprid raises a question of bias.

Another concern is EPA’s reliance of non-peer reviewed industry data and lack of independent peer-reviewed data from companies like Bayer and others with an economic interest in downplaying the hazards of Imidacloprid in the EPA Ecological Risk Assessment. For example, EPA cites information provided by Bayer AG consisting of numerous unpublished studies that have not been subjected to independent peer-review and critique by other researchers not paid or under a binding contract by the pesticide firms. 

Additional areas of public concern over effects of the nicotinyl insecticide Imidacloprid are as follows:

  1. Imidacloprid formulations, Imidacloprid parent, metabolites and degradates (guanidine, olefin and urea) are systemic pesticides. A concern is how much degree of variation is in the chemistry of the Imidacloprid formulations. How much variation occurs in the Imidacloprid percent applied?
  2. Imidacloprid formulations, Imidacloprid parent, metabolites and degradates (guanidine, olefin and urea) are neurotoxic to insects including honey bees in low concentrations in the low parts per billion range and lower detection limits need to be used of less than one ppb. EPA needs to consider other metabolites of Imidacloprid.
  3. Imidacloprid formulations, Imidacloprid parent, metabolites and degradates (guanidine, olefin and urea) have greater neurotoxic effects on honey bees due to genomic vulnerability.
  4. Imidacloprid formulations are persistent in the environment.
  5. Imidacloprid formulations, Imidacloprid parent, metabolites and degradates (guanidine, olefin and urea) may act synergistically with fungicides in complex combinations.
  6. Honey bees may avoid higher concentrations of neonicotinoids in plants with available pollen and nectar. Do honey bees have the ability to learn to avoid contact with pesticides like Imidacloprid?
  7. Imidacloprid formulations carry acute toxicity that is extremely harmful to bees.
  8. Imidacloprid may be present in high fructose corn syrups fed to commercial honey bees. Recent testing in Minnesota found that high fructose corn syrup (HFCS) fed to honeybees contained eight parts per billion of neonicotinoids. Imidacloprid in HFCS needs to be fully investigated by EPA.
  9. Neonicotinoids may be present in recycled hives fed to honey bees. Studies need to be conducted on the effects of feeding parts of recycled hives to honey bees.
  10. Translocated neonicotinoids that foraging honey bees may drink from in the water exudates on the plant leaves need to be investigated.
  11. Reports have indicated the presence of mercury in HFCS and mercury is a potent toxin to look at.
  12. EPA needs to investigate areas with healthy colonies of honey bees but no large-sale agricultural uses of Imidacloprid like anecdotal reports by beekeepers from Custer County, Colorado.

EPA needs to ensure that the pesticide industry is not preventing independent research and bias.

Recently a group of twenty-six independent scientists wrote to the EPA expressing their concerns about the difficulties they faced conducting and attempting to carry out independent research on biotech crops with Patents held by private companies. The EPA needs to make sure that the pesticide industry is not preventing independent research, which has been a problem because manufacturers spend millions of dollars funding research and do not want negative findings to reduce the potential for pesticide sales.

The Sierra Club sent a letter to EPA Docket # EPA-HQ-OPP-2008-0836 on February 22, 2009 sharing concerns about the inability of independent scientists to conduct research. Those concerns are included in these comments below, because the manufacturer of Imidacloprid has similar vested interests to biotech companies in preventing independent research by independent scientists who might observe negative results and make negative findings on this pesticide.

Comments made to EPA Docket # EPA-HQ-OPP-2008-0836 on February 22, 2009.

The Sierra Club strongly supports scientific concerns being raised about the current state of Bt corn insect research in the U.S. recently described by a group of independent scientists in Docket comments revealing major research obstacles in the field biotechnology crop development. The end result is that many university scientists are being prevented by biotechnology seed companies from investigating the effectiveness and environmental impacts of genetically engineered crops for fear of negative findings. Research can not be properly conducted unless scientists remain independent, objective and unbiased in their fields of inquiry. The state of Bt corn insect research appears to parallel serious problems in pharmaceutical research where drug firms made efforts to block the release of negative findings in peer-reviewed journals.

Serious research obstacles in investigating Bt corn insect relationships were outlined by a group of twenty-six leading corn insect scientists in comments to the EPA Docket February 9, 2009 (comment tracking # 8084de39). The independent scientists shared their serious concerns about how research is being controlled and manipulated by biotechnology firms through technology/stewardship agreements in a way that prohibits independent and objective research needed by EPA’s OPP and the FIFRA SAP to make the best scientific decisions on Plant Incorporated Protectants (PIPs). These scientists present a compelling case why EPA and the FIFRA SAP should not approve a request by Pioneer Hi-Bred International, Inc. for registration of Optimum¨AcreMaxTM 1 Insect Protection at this time.

Docket statement of February 9, 2009 by twenty-six independent scientists:
“Technology/stewardship agreements required for the purchase of genetically modified seed explicitly prohibit research. These agreements inhibit public scientists from pursuing their mandated role on behalf of the public good unless the research is approved by industry. As a result of restricted access, no truly independent research can be legally conducted on many critical questions regarding the technology, its performance, its management implications, IRM, and its interactions with insect biology. Consequently, data flowing to an EPA Scientific Advisory Panel from the public sector is unduly limited.”

Significant Bt corn insect research obstacles likely exist in investigating questions about an application of Pioneer Hi-Bred International, Inc. for registration of Optimum¨ AcreMaxTM 1 Insect Protection, which is a corn seed blend containing seeds that express the Bt toxins Cry34Ab1, Cry35Ab1, and Cry1F in a stack for corn rootworm (CRW) and lepidopteran protection mixed with seeds that express only Cry1F for lepidopteran protection (i.e. refuge in the bag for CRW). As a result, Sierra Club urges EPA’s Office of Pesticide Programs and the FIFRA Science Advisory Panel to require additional research be carried out and require complete transparency of this research, which evidently has not been the case over the last fifteen years.

In addition, Sierra Club concurs that the difficulties of conducting independent Bt corn insect research are likely applicable to all EPA decisions on Plant Incorporated Protectants and not just with respect to the pending application by Pioneer Hi-Bred International, Inc. for registration of Optimum¨AcreMaxTM 1 Insect Protection on Bt corn. The EPA’s OPP and FIFRA SAP need to step back for at least one year or more and review the critical situation preventing basic, objective independent research on PIPs from being performed in the US, which is a completely unacceptable situation. Furthermore, Sierra Club supports the need for complete transparency of research on all Plant Incorporated Protectants as vital to the public interest in maintaining an adequate U.S. food supply and it’s obvious that the opposite situation exists in preventing good science from being conducted and published by independent scientists.

Sierra Club strongly supports the use of best available science to review Pioneer Hi-Bred International’s request for registration of Optimum¨ AcreMaxTM 1 Insect Protection. In view of February 9, 2009 Docket submission and concerns that the scientific  investigation of genetically engineered crops such as the Bt corn in this case suggests, there is a profound need for improvement and regulatory oversight by EPA.

As EPA has indicated, additional Bt corn insect research is apparently what is needed to resolve the uncertainties that EPA’s OPP is requesting comments about in the Federal Register Notice of December 10, 2008 (p. 75099, Vol. 73, No. 238). EPA’s OPP reviewed Pioneer Hi-Bred’s submitted studies and modeling chapter and identified areas of uncertainties in the CRW biology, population genetics, and modeling. The EPA is seeking the assistance of the FIFRA SAP to address the scientific issues associated with the seed mix proposal for CRW resistance management and provide the Agency with guidance on the implications of the uncertainties. Seven areas of uncertainties need to be properly investigated and include:

  1. Mode of action of Cry34/35Ab1 (i.e. toxic or repellent) to exposed CRW and implications for a seed mix,
  2. Aspects of corn rootworm pest biology including the effects of delayed emergence and uneven sex ratios on random mating and ultimately on the rate of resistance evolution in a seed blend environment;
  3. Assumptions about initial resistance gene frequency to Cry34/35Ab1;
  4. Contributions of tolerance (minor) and resistance (major) genes and selection consequences in corn rootworm exposed to Cry34/35Ab1 in a seed blend environment;
  5. Mortality for individuals being heterozygous (XY) and susceptible (XX) for the tolerance (minor) gene;
  6. The overall simulation model (i.e. is it adequate to evaluate the proposed seed mix for Cry34/35Ab1); and
  7. The mechanics of mixing refuge seed with Cry34/35Ab1 seed into a single bag and the potential distribution (i.e. random or non-random) of refuge plants within planted fields.

Additional Bt corn insect research may take several years. Prudent course of action by EPA’s FIFRA Science Advisory Panel is not to approve the Pioneer Hi-Bred’s registration until all uncertainties have been fully addressed and resolved through independent scientific research.

In conclusion, the EPA’s OPP and the FIFRA Science Advisory Panel need to comprehensively investigate and respond to the scientific concerns about the current state of Bt corn insect research and Plant Incorporated Protectants in the U.S. as described by independent scientists revealing serious research obstacles in the field of biotechnology crop development.

Finally, the EPA must ensure that beneficial insects like honey bees are fully protected from high-risk uses of toxic pesticides. U.S. food security depends greatly on pollinators such as honey bees at a time of growing climate change and major drought occurring in large areas of the U.S. agricultural regions from coast to coast. It is recommended that the EPA cancel any uses of Imidacloprid that are found to pose high risks to bees and other pollinators.
Neil J. Carman, Ph.D.
Sierra Club Genetic Engineering Action Team


Close This Window