New RNAi 'gene silencing' pesticides are being developed by Agro-biotec companies to kill insects by “switching off”
their essential survival genes. [1] This use of genome technology has the potential to devastate non-target species,
such as honeybees and butterflies, and to compromise environmental and human health. [2][3]
The pesticides are the next battlefield for food safety and environmental sustainability. There is clear scientific
evidence that they present a new level of complexity and risk.
Gene-Silencing pesticides could modify other species, and concerns of independent scientists must be taken seriously.
Regulators must urgently ensure these novel gene-silencing pesticides are regulated for safety.
Agro-biotech industry executives hope RNAi pesticides can remedy the total failure of genetically modified (GM) plants
to control weeds and pests. GM plants are designed to tolerate pesticide applications throughout the growing season,
without killing the crop. The overuse of these pesticides has caused a resistance in weeds that in the US has devastated
farmer’s crops. Tolerance to the insecticide Bacillus thuringiensis (Bt) Cry endotoxin in GM plants has also developed
in the insects the GM plants were designed to kill. This has not, however, stopped the march to find new ways to kill
pests and weeds that overcome this tolerance and resistance. [4]
The development of new gene silencing pesticides comes at the same time as the push by commercial interests for
deregulation of products from Gene Editing. Both are threats to the integrity of the food system and the environment.
“The current situation in New Zealand and overseas is that RNAi pesticides are not being regulated as Genetically
Engineered organisms. They need to be," says Jon Carapiet, spokesman for GE-Free NZ.
"Far from deregulation of Gene Editing, the regulations need to be strengthened and expanded to include gene silencing
pesticides."
The Royal Society has supported relaxing precautionary GE laws and reviewing regulations. This is unreasonable, if new
regulations ignore the risks from gene editing and gene silencing pesticides.
It is vital that the scientific community resist the temptation to ignore safety in the haste to commercialise products
and profit from intellectual property.
The current status is one of incomplete and inadequate knowledge of unintended genetic changes by novel and experimental
gene technologies.
There is potential for a new Silent Spring if we do not regulate these powerful gene technologies.
References:
[2] Mogren and Lundgren (2017), In silico identification of off-target pesticidal dsRNA binding in honey bees (Apis
mellifera). PeerJ 5:e4131; DOI 10.7717/peerj.4131
[3] Romeis et al.(2020) Assessing the Risks of Topically Applied dsRNA-Based Products to Non-target Arthropods https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7289159/
[4] Schütte, G., Eckerstorfer, M., Rastelli, V. et al. Herbicide resistance and biodiversity: agronomic and
environmental aspects of genetically modified herbicide-resistant plants. Environ Sci Eur 29, 5 (2017). https://doi.org/10.1186/s12302-016-0100-y