A research paper, emerging from a IUPAC project, provides guiding principles for the regulatory evaluation of nanopesticides.
Drawing from their international contacts around the world, the Human Health Risk Consideration of Nano-enabled Pesticides for Industry and Regulators project team worked in close collaboration with industry and government (regulatory agencies) to develop a comprehensive framework for assessing potential human health impacts of nanopesticides.
This approach will help overcome potential barriers for regulators and industry globally, taking into account, for example, differing international regulatory requirements as well as community concerns about nanopesticides.
Monitoring pesticides curbed risks
In many countries worldwide, improved regulation and monitoring of new pesticide products has minimised some of the more acute risks (such as those posed by Persistent Organic Pollutants (POPs)), and has generally led to improved environmental and health management. However, farmers have continued to battle problems with modern pesticides, such as chemical resistance, leaching into the environment and safety to human health.
Melanie Kah at the University of Auckland (New Zealand) and a lead author of this paper, commented: “In the past two decades, the research community started looking to chemical alternatives including nanopesticides, which offer a safer and more promising future in their ability to target weeds, worms, mites, ticks, bacteria, and fungi.”
Nanopesticides subjected to rigorous testing
Linda Johnston, an expert in quantifying the nature and characteristics of nanoparticles in relation to their potential impact on human health, commented: “Nanopesticides, like other alternatives, are subject to rigorous safety testing to prevent unintended consequences.”
It’s important to note that some types of nanopesticide products are rapidly coming onto the market and have started gaining traction with farmers. “One of the big drawcards of nanopesticides is the protection they offer to plants as well as to the non-target organisms in the environment. This is primarily because of their greater effectiveness and lower toxicity,” explains Rai Kookana, from CSIRO (Australia), and “They are also known for their improved uptake by plant and reduced wash-off during a rain event.”
Nanopesticides as ‘silver bullets’
The framework study focusses on human health risk assessments for nanopesticides, as well as nanofertilisers. Kookana emphasises that the framework doesn’t attempt to provide an exhaustive list of the effect of nanopesticides on humans, or frame nanopesticides as the ‘silver bullet’ of agrichemicals.
The hope is it will be used as a starting point for understanding and addressing the concerns about nanopesticides. The paper provides a decision tree and pathway to risk assessment, keeping in mind the different stages of human exposure – at mixing and loading, application and post-application, with each stage involving different dilutions and forms of the pesticide, or exposure opportunities.
The framework also helps industry to understand what questions the risk assessor has in mind and what data and information need to be provided to satisfy the regulatory requirements. “Building on the works from previous IUPAC projects, this study is an important step towards an harmonized approach for nanopesticides that can be accepted by regulatory agencies when assessing their toxicological impacts,” says Kookana.
This article was first published by IUPAC.
