Nanomaterials could make the use of pesticides more efficient and sustainable
While almost 4 million tonnes of conventional pesticides are used annually, only a small amount – 1% to 25% – reaches the target organisms, leaving a large proportion released into the environment as a potential hazard. This is due to many factors such as drift, volatilization, roll off, dust drift, leaching and more.
Non-target organisms such as livestock, bees, birds and other pollinators are also negatively affected.
Ineffective control of pests and crop diseases due to the poor application efficiency of traditional pesticides can account for 20-40% of global crop losses and cause economic damage of around US$220 billion per year. These losses, combined with global climate change, desertification, and escalating land degradation — along with other stresses from global change — are likely to exacerbate these losses in the years to come.
The solution to these problems could be a material 10,000 times smaller than the width of a single human hair – a nanomaterial.
“Nanomaterials with the extraordinary ability to encapsulate and release pesticide active ingredients (AIs) in a controlled, targeted, and synchronized manner may offer new opportunities to increase pesticide efficiency compared to traditional pesticides,” said Dengjun “Kevin” Wang, assistant professor of aquarium chemistry at the College of Agriculture’s School of Fisheries, Aquaculture and Aquatic Sciences.
Wang is the lead author of a recent article in the journal Nature Nanotechnology titled “Nano-enabled Pesticides for Sustainable Agriculture and Global Food Security.” Nature Nanotechnology is a leading peer-reviewed scientific journal published by Nature Publishing Group.
“Because of their small size, large surface area and high tunability, nanomaterials can act as nanocarriers to encapsulate pesticide active ingredients or AIs,” Wang said. “The encapsulated nanopesticides can deliver active ingredients in a controlled, targeted and synchronized manner according to plant needs and abiotic stress. This will not only increase the use efficiency of nanopesticides, but also minimize potential hazards from AI leaks to the environment.
Analysis by Wang and his co-authors shows that the overall effectiveness of nanopesticides against target organisms is 31.5% higher than conventional pesticides (314 studies), including an 18.9% increased efficacy in field trials (47 studies) . The toxicity of nanopesticides to non-target organisms is 43.1% lower (59 studies), underscoring a reduction in collateral damage to the environment.
The premature loss of AIs before reaching target organisms (e.g. drift and volatilization) is reduced by 41.4%, coupled with a 22.1% lower leaching potential of AIs in soils.
“Nanopesticides also offer other benefits, including improved leaf adhesion, improved crop yield and quality, and controlled release of AIs in a rapidly changing climate,” Wang said. “When harnessed, these benefits can promote higher crop yields, thereby contributing to sustainable agriculture and global food security.”
The next steps in research, Wang said, are finding seed capital to support field trials of nanopesticides to control pests and pathogens, patenting nanopesticides if field trial results are promising, and if so, finding industrial partners.
“Nanotechnology also has great potential to develop nano-fertilizers and nano-vaccines for applications in agriculture, aquaculture and beyond,” he added.
(Written by Paul Hollis)