Tag Archives: Melanie Kah

Nano-pesticides or nanopesticides or nano pesticides

It’s the spelling that’s driving me nuts. In the last year it seems to have gotten quite higgledy piggledy and so we have this salad of one word, two words, and hyphenated words for anything  prepended by nano.  I hope it settles soon but in the meantime, here’s an Aug. 12, 2013 news item on Azonano concerning nano-pesticides,

Research is urgently needed to evaluate the risks and benefits of nano-pesticides to human and environmental health. Melanie Kah and Thilo Hofmann from the Department of Environmental Geosciences of the University of Vienna recently performed an extensive analysis of this emerging field of research.

The results were published June 6th in the internationally recognised journal “Critical Reviews in Environmental Science and Technology”. The study presents the current scientific state of art on nano-pesticides and identifies direction priorities for future research.

The University of Vienna June 20, 2012  press release, which originated the news item (I’ll explain the one year gap later in this posting), describes some of the concerns raised in the study,

Nano-pesticides encompass a great variety of products, some of which are already on the market. The application of nano-pesticides would be the only intentional diffuse input of large quantities of engineered nano-particles into the environment. Innovation always results in both drawbacks and benefits for human and environmental health. Nano-pesticides may reduce environmental contamination through the reduction in pesticide application rates and reduced losses. However, nano-pesticides may also create new kinds of contamination of soils and waterways due to enhanced transport, longer persistence and higher toxicity.

The current level of knowledge does not allow a fair assessment of the advantages and disadvantages that will result from the use of nano-pesticides. As a prerequisite for such assessment, a better understanding of the fate and effect of nano-pesticides after their application is required. The suitability of current regulations should also be analyzed so that refinements can be implemented if needed. Research on nano-pesticides is therefore a priority for preserving the quality of both the food chain and the environment.

Here’s a link to and a citation for the paper,

Nano-pesticides: state of knowledge, environmental fate and exposure modeling: Melanie Kah, Sabine Beulke, Karen Tiede and Thilo Hofmann. Critical Reviews of Environmental Science and Technology, Volume 43, Issue 16, 2013 , pages 1823-1867 DOI: 10.1080/10643389.2012.671750

http://www.tandfonline.com/doi/abs/10.1080/10643389.2012.671750

There was a 2012 version of this paper posted, which was when the press release was originally written and posted at the University of Vienna website, but June 2013 is when the paper was officially published. It is behind a paywall but thankfully one of the authors, Melanie Kah, gave Katy Edgington an interview about the study for Edgington’s June 26, 2012 article on scienceomega.com,

“Although some research is ongoing, one application that is fairly well-developed involves the injection of nanoscale zero-valent iron particles into groundwater to degrade certain contaminants. This is an example of something that is still under development but which is already being applied, as the technique is currently in use on a large scale in the United States.” [says Kah]

A project is underway in the department which aims to help make the technique more widely applicable, and another – at the complete opposite end of the scale in terms of its development – is looking at a potential application for carbon nanotubes.

“People have suggested that carbon nanotubes could be used to replace activated carbon, the material used worldwide to decontaminate water,” clarified Dr Kah. “It is suggested that carbon nanotubes have different properties which will complement activated carbon, but this is only at the laboratory scale so far.”

It is important to steer clear of making broad generalisations about the risks and benefits of nanopesticides as compared to conventional pesticides, Dr Kah emphasised. They cannot be considered as a single entity; rather each case must be taken on its own merits.

In their review of the literature on the topic, the authors also discuss how the adequacy of existing legislation and regulation may be affected in light of the development of nanopesticides in various forms.

“I think it is far too early to propose any amendments to the current regulation,” Dr Kah stated. “It appears from our analysis that a lot of nanopesticides would be well covered by the European regulation on plant protection products because this regulation is very thorough; indeed it is probably the strictest in the world.”

I imagine that since the initial publication of the paper and the interview, there may have been a few changes to the paper and refinements to Kah’s ideas but the Edgington article does provides some interesting insight, especially if you don’t have access to the paper.