- Inventory of the emerging new class of RNAi-based pesticides, which have been approved for experimental and commercial use or that are likely to be this in the near future, including the genes that they target in insects, the chemistry involved with their production and their efficacy (e.g. stability after uptake) and the plant health issues that can be addressed with. The inventory will also examine possible uses of RNAi with other than lethal effects in target insects.
- Review of how these pesticides are regulated in various countries, e.g. whether they are treated as a specific category
- Review of the approaches followed for the safety assessment of these pesticides
- Identification of issues that can merit from international harmonization
- No internationally harmonized safety assessment approach exists for this kind of pesticides / biopesticides other than GM food crops in which RNAi is expressed [Note: OECD is currently drafting guidelines for the safety aspects to be considered for RNA-based pesticides]
- For risk, regulatory, and policy professionals, an overview of the progress and the issues needing harmonization will be useful
Genetically modified (GM) crops expressing insecticidal proteins are a well-known class of GM biopesticides (e.g. defined by the US Environmental Protection Agency as “plant-incorporated protectants”). These GM crops are grown on a vast acreage in many countries around the globe, while other groups of GM biopesticides are less known.
There has been a surge recently in the interest in the development of RNAi-based pesticides, which are in an advanced experimental stage of development. These include both GM crops expressing small RNA molecules targeting pest insects as well as preparations of dsRNA, for example, that act in combination with a delivery method, such as topical sprays that could be applied to crop fields but also in households and other environments, once approved.
Given the nature of these pesticides, it is obvious that the associated safety issues for humans, animals, and the environment may differ from what has been observed for other classes of pesticide and GM “plant-incorporated protectants.”
There appears to be no regulatory harmonization or global consensus yet on how to assess these products for potential impacts on health and environment (apart from the more generic approaches towards assessing GM crop safety), indicating potential for trade disputes among nations with different regulatory requirements (or â€œzero toleranceâ€ because of lack of requirements).
The project will make an overview of the progress of RNA-based approaches, their chemistries and mode of action, as well methods for their delivery to the target. Moreover the regulatory environment for these biopesticides in various legislative environments (e.g. US EPA, APVMA in Australia) will be explored and reviewed, particularly with a view on whether their distinct characteristics also have led to specific regulations and safety requirements. Potential gaps for international harmonization will be identified and highlighted. To our knowledge, the facts reviewed and reported will be a first of their kind.
- New Scientist, 23 March 2010, “Reasons to welcome gene-silencing pesticides,” https://www.newscientist.com/article/mg20527521.500-reasons-to-welcome-genesilencing-pesticides.html
- W. Parrot, B. Chassy, J. Ligon, L. Meyer, J. Petrick, J. Zhou, R. Herman, B. Delaney, M. Levine (2010) Application of food and feed safety assessment principles to evaluate transgenic approaches to gene modulation in crops. Food and Chemical Toxicology 48, 1773-1790. https://dx.doi.org/10.1016/j.fct.2010.04.017
- Center for Environmental Risk Assessment & ILSI Research Foundation (2011) Problem Formulation for the Environmental Risk Assessment of RNAi Plants: Conference Proceedings. https://cera-gmc.org/docs/cera_publications/pub_08_2011.pdf
- Hao Zhang et al. (2012) Feasibility, limitation and possible solutions of RNAi-based technology for insect pest control. Insect Control 20, 15-30. https://dx.doi.org/10.1111/j.1744-7917.2012.01513.x
- H. Huvenne, G. Smagghe (2010) Mechanisms of dsRNA uptake in insects and potential of RNAi for pest control: A review. Journal of Insect Physiology 56, 227-235. https://dx.doi.org/10.1016/j.jinsphys.2009.10.004
Presentations given before 2019:
- Symposium “Agricultural Biotechnology”, Session “Challenges associated with Global Adoption” (13 August 2014), 13th IUPAC International Congress of Pesticide Chemistry at the 248th American Chemical Society National Meeting, San Francisco, USA, 10-14 August 2014.
- Informa’s Ag-Bio Congress, Biopesticides Day 3 (The Science behind Biopesticides), Amsterdam, Netherlands, 2-4 December 2015.
- Second iPLANTA Conference, “RNAi: The Future of Cross Talk”, Poznan, Poland, 15 February 2018.
April 2020 update – The following presentations and publications were completed in 2019:
Presentation on RNAi at the IUPAC2019 international pesticides congress in Ghent, May 20th, 2019: G. Kleter*, IUPAC Project team, H. Kuiper, “RNA interference-based crop protection: Food & feed safety, detectability, regulation, and efforts towards international harmonization.”
Papers in preparation, submitted for publication in 2019
G.A. Kleter, H.A. Kuiper, “RNA Interference in crop protection: Scoping potential food & feed safety issues” submitted to Comm. Appl. Biol. Sci. Ghent Univ. (congress issue)
G.A. Kleter, “Food safety assessment of crops engineered with RNA interference and other methods to modulate expression of endogenous and plant pest genes” submitted and re-submitted (after comments from referees) to Pest Management Science (special congress issue edited by Prof S. Duke)
In preparation of final manuscript, a literature research, for example analogues of dsRNA currently being applied for plant protection (e.g. RNA plant viruses as biological pesticides) was completed.
A final review engendering recent developments (e.g. outcomes of desk studies on non-coding RNA’s safety commissioned by EFSA) and focusing on potential for harmonization of safety requirements is expected for 2020.
Feb 2021 update – A mini-review entitled “Food safety assessment of crops engineered with RNA interference and other methods to modulate expression of endogenous and plant pest genes” has been published in Pest Management Science: Kleter, G. A. 2020; https://doi.org/10.1002/ps.5957 (published online 9 June 2020)
Last update 16 Feb 2021