Project Details Guiding principles to facilitate a harmonized ecological risk assessment framework for nano-pesticides in the environment

Project No.:
2012-020-3-600
Start Date:
01 July 2012
End Date:
12 March 2018
Division Name:
Chemistry and the Environment Division
Division No.:
600

Objective

The overall objective of this project is to develop a set of guiding principles to facilitate a harmonized approach for the ecological risk assessment of nano-pesticides.

Rationale: 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. Currently there is no broadly accepted approach for the above purpose. The OECD through the Working Party on Manufactured Nanomaterials (WPMN) is currently undertaking extensive but broad-based work related to nanomaterials in the environment. This work excludes nano-pesticides. By contrast, the proposed project focuses solely on nano-pesticides.

Description

Nano technology is emerging as a highly attractive tool for formulation and delivery of pesticide active ingredients as well as enhancing and offering new active ingredients. For example, nanocapsules based on polymers are being designed for controlled release of active ingredient as well as enhanced delivery through improved penetration through leaves. Some active ingredients are being reformulated in the form of nanoparticles to harness the extraordinary properties of nanomaterials. While a clear definition of nano-pesticides is still being sought, the term commonly refers to application of nanotechnology in delivery or formulation of pesticides.

Two potentially challenging questions arise: (i) how the fate, behavior and ecological risks of nano-pesticides differ from conventionally formulated pesticide active ingredients; and (ii) how the potential risks associated with nano-pesticides can be assessed in a harmonized and scientifically sound way? Currently there is no broadly accepted approach to answering these questions.

To achieve a globally harmonized approach to the ecological risk assessment of nano-pesticides, it is essential to develop a set of criteria or guiding principles on the basis of which the environmental risk of nanopesticides can be evaluated. Owing to the complexity of nano-pesticide formulations, the current approach applied to conventional (non-nanopesticides) is not directly applicable to nano-pesticides.

Currently a considered set of “guiding principles” is needed for ecological risk assessment of pesticides is missing. However, some agencies such as Australian Pesticide and Veterinary Medicines Authority (APVMA) have taken an initiative and set the ball rolling. These principles, when developed with leaders in the agrochemical industry and regulatory agencies, are expected to facilitate a more uniform approach to evaluate nanopesticides for their ecological impact.

This project would consist of three phases.

  1. Phase I – collate data on potential forms of so-called nanopesticides and attempt to provide a clear definition on what a nanopesticide is. A mapping of product type, their functionality and interactions with other ingredients in the formulation would be undertaken. At the end of phase I, a decision on reframing the objectives/focus of the project, if needed, would be made based on data availability.
  2. Phase II – establish the key factors that would determine the fate and behaviour of nanopesticides as opposed to conventional pesticide ingredients and potential implications of these risk factors of nano-pesticides. Decision-making matrices developed by national bodies for this purpose would be reviewed and considered.
  3. Phase III – recommend a set of guiding principles (criteria) for ecological risk evaluation of nano-pesticides, and demonstrate the potential application of the approach using select examples of nanopesticides.

Progress

March 2013 update – project annoucement published in Chem Int Mar-Apr 2013, p. 18

April 2014 update – The first workshop associated with the project was held in Europe at the University of York on 18-19 May 2013 coinciding with SETAC Europe meeting in Glasgow. The workshop was jointly sponsored and organised by IUPAC and APVMA (The Australian Pesticide and Veterinary Medicines Authority). APVMA is the regulatory agency in Australia dealing with nanomaterials for applications in agriculture and veterinary medicines.

The workshop was attended by 18 experts from Europe, USA and Australia. Together they represented academia, researchers, and regulatory agencies. The regulatory agency of the UK – Food and Environment Research Agency (FERA), had strong representation throughthree FERA delegates, and including task group member Dr Chris Sinclair. Dr Philip Reeves (Chief Scientist, APVMA and project task group member) played a major role in liaising with industry and other regulators. The workshop was hosted by Dr Alistair Boxall (University of York). All project task group members were invited but only some could attend.

During the workshop, after overview presentations, notably by Dr Melanie Kah (University of Vienna), the experts worked over two days in parallel in four different groups; covering aspects, namely (1) Definitions and Regulatory considerations (2) Properties and Characterisation, (3) Environmental fate and Behaviour, and (4) Effects and Risk Assessment. The synthesis from the workshop discussions was captured in a ‘Perspective Article’ published in April 2014 in Journal of Agriculture and Food Chemistry: dx.doi.org/10.1021/jf500232f

In this article, the current approaches for environmental risk assessment of pesticides are reviewed and the question of whether these approaches are fit for purpose for use on nanopesticides is addressed. Potential adaptations to existing environmental risk assessment tests and procedures for use with nanopesticides are discussed, addressing aspects such as analysis and characterisation, environmental fate and exposure assessment, uptake by biota, ecotoxicity and risk assessment of nanopesticides in aquatic and terrestrial ecosystems. Throughout, the main focus is on assessing whether the presence of the nanoformulation introduces potential differences relative to the conventional active ingredients. The proposed changes in the test methodology, research priorities and recommendations would facilitate the development of regulatory approaches and a regulatory framework for nanopesticides.

The second major project activity is to be held in San Francisco, in the form of a Special symposium, at the 13th IUPAC International Congress of Pesticide Chemistry (iupac2014.org). The symposium will have representations from industry, regulatory and research communities. Dr Darren Anderson from the Vive Corp would give the industry perspective. Dr Phil Reeves of APVMA will provide Regulatory perspective. Dr Melanie Kah will review the current state of science on nanopesticides. Dr Alistair Boxall will bring the key messages from the 2013 workshop. Dr Kookana will identify key knowledge gaps to kick start the discussion session during the symposium.

 

Nov 2014 update – Update/report published in Chem. Int. Nov-Dec 2014, p. 20-21; DOI: 10.1515/ci-2014-0617

Jan 2017 update published in Chem. Int. Jan 2017, p. 24; https://doi.org/10.1515/ci-2017-0113

July 2017 update – The findings of this Nanopesticides project and its follow-up project 2016-016-2-600 were presented at ACS Agro meeting in Washington in August 2017.

Project completed

Last update 12 March 2018