The overall objective of this project is to assist industry, contract research organizations (CROs) and regulators in determining an acceptable and practicable approach for generating the data required for the registration of nanopesticides.
Nanotechnology is emerging as a highly attractive tool for the formulation and delivery of pesticide active ingredients as well as enhancing and offering new active ingredients. Several nano-enabled pesticides are in the pipeline and are expected to be presented for registration. US EPA recently registered nano-enabled pesticides such as AZteroid, which is based on Vive Crop Protection’s Allosperse (a polymer-based delivery system).
Currently there is a lack of understanding among industry and regulators on:
• The environmental fate and effects data that regulators will require to determine the risk profile of nanopesticides.
• What methods/approaches are appropriate and acceptable to give industry confidence in obtaining and submitting the data required to satisfy the regulatory requirements.
A previous IUPAC project (project 2012-020-3-600) has laid down some guiding principles for consideration by regulatory agencies to develop a harmonized approach (Kookana et al. 2014, Journal Ag and Food Chemistry, 62: 4227-4240). The above need emerged from stakeholder consultations undertaken during the above project, where industry representatives and regulators highlighted the need for some specific guidance on data requirements and the associated methodology, based on specific product-types and as driven by the problem-formulation stage of risk assessment.
A practicable approach for generating sound data required for satisfying regulatory requirements for the purposes of registration of nanopesticides will be presented as outcome of this project.
Nanopesticides or nano-enabled plant protection products represent an emerging technological development that, in relation to pesticide use, could offer a range of benefits including increased efficacy, durability and a reduction in the amounts of active ingredients that need to be used. A number of formulation types have been suggested including emulsions (e.g. nanoemulsions), nanocapsules (e.g. with polymers) and products containing pristine engineered nanoparticles, such as metals, metal oxides and nanoclays. The increasing interest in the use of nanopesticides raises questions as to how to assess the environmental risk of these materials for regulatory purposes.
The previous IUPAC Nanopesticides project (project 2012-020-3-600) has developed some high level thinking about the key criteria that could help decide if a nanopesticide needs to be treated as a conventional pesticide or if it needs to undergo a separate risk assessment process, as published by Kookana et al. 2014 (J. Ag Food Chem 62: 4227-4240). The robustness or durability of the formulation is one such criteria that could help guide the above decision, for example. The industry feedback received so far indicates that the above is a workable approach. While the philosophy in Kookana et al. 2014 is now being actively considered by regulatory agencies internationally (e.g. USEPA, Environment Canada, APVMA Australia, EFSA Europe), there is a need to expand the thinking and provide more practical information to answer some key questions, such as those listed below:
- When a new product is presented to the regulators, what are the key questions that they would like to ask? This essentially defines the problem formulation step in the ERA framework.
- What are the key characterization and analytical requirements for the specific product that may be necessary to answer the question posed at 1 for a specific product type?
- What are the specific methods or approaches for environmental fate and effects that are readily available and appropriate to answer the questions for the specific product under consideration?
- What are the current knowledge gaps and uncertainties that the regulators and industry need to consider for a pragmatic approach to decision making?
This project will consist of three phases.
Phase I – Bring together a core group of task members to define the scope of the project, identify specific active ingredients and product types, and undertake problem formulation from the risk assessment perspective.
Phase II – Organize a workshop bringing together expertise from industry, regulatory bodies and researchers on environmental fate, effects and the risk assessment of nano-enabled pesticides as well as characterization of nanomaterials that have been identified in phase I.
Phase III – Recommend a sound methodological approach for generating data that is likely to be needed by the regulators. Identify research priorities where current knowledge or methodology are found to be inadequate.
Mar 2017 – Project announcement published in Chem. Int. Jan 2017, p. 24; https://doi.org/10.1515/ci-2017-0113
May 2017 update – In the current project, we intended to test the framework (Kookana et al. 2014) for specific products or case studies. For this reason we brought together a group of experts together in a Workshop in Nantes, France, to discuss three case studies and identify one to look more closely. We had a strong involvement of industry (Dr Darren Anderson of Vive Crop Protection, Canada) and regulators (Dr. Glen Walker of Dept of Environment, Government of Australia) as well as researchers, including from the UK, Sweden, Austria, Portugal, Australia. During the two-day workshop in Nantes, we developed a conceptual model to map new products on theoretical scheme to identify critical difference that a nano-enabled product presents in comparison with a conventional molecule.
Based on this workshop and subsequent work by the project team, we have now developed an article entitled “Ecological risk assessment of nano enabled pesticides: A perspective on problem formulation” that has been submitted to the special issue ‘Nanotechnology applications and implications of agrochemicals toward sustainable agriculture and food systems’ under the “Perspectives” category. In this paper, a group drawn from regulatory agencies, academia, research and the agrochemicals industry offers a perspective on relevant considerations pertaining to the problem formulation phase of the ecological risk assessment of nano-enabled pesticides. The paper is currently under review.
Mar 2019 update – To test the risk assessment framework developed for nanopesticides (Kookana et al. 2014) in a previous project (2012-020-3-600) industry, regulators, researchers, academia were brought together in a Workshop, during which a conceptual model was developed to theoretically evaluate new nanopesticides products to identify critical difference that a nano-enabled product may present to the environment in comparison with a conventional product. This conceptual model was applied to a specific product (a herbicide encapsulated in a hydrogel designed for its effective delivery into subsoils) to illustrate the application of the framework. Co-authored by a group drawn from regulatory agencies, academia, research and the agrochemicals industry, an article entitled “Ecological risk assessment of nano enabled pesticides: A perspective on problem formulation” was developed to offer a perspective on key considerations pertaining to the problem formulation phase of the ecological risk assessment of nano-enabled pesticides. This paper has now been published in Journal Agricultural and Food Chemistry. The full citation of the article is as follows:
Walker, G; Kookana, RS; Smith NE, et al. (2018). Ecological risk assessment of nano-enabled pesticides: A perspective on Problem Formulation. Journal of Agricultural and Food Chemistry, 66(26): 6480-6486; https://doi.org/10.1021/acs.jafc.7b02373.
Page last updated 26 Mar 2019