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Nanocides: Current State of the Art 2005
Get the Full report Down on the Farm, How will effect Agriculture and Food Pesticides containing nano-scale active ingredients are already on the market, and many of the world's leading agrochemical firms are conducting R&D on the development of new nano-scale formulations of pesticides. BASF of Germany, the world's fourth ranking agrochemical corporation (and the world's largest chemical company), recognizes nanotech's potential usefulness in the formulation of pesticides. 27 BASF is conducting basic research and has applied for a patent on a pesticide formulation, "Nanoparticles Comprising a Crop Protection Agent," that involves an active ingredient whose ideal particle size is between 10 and 150 nm. 28 The advantage of the nano-formulation is that the pesticide dissolves more easily in water (to simplify application to crops); it is more stable and the killing-capacity of the chemical (herbicide, insecticide or fungicide) is optimized. Bayer Crop Science of Germany , the world's second largest pesticide firm, has applied for a patent on agrochemicals in the form of an emulsion in which the active ingredient is made up of nanoscale droplets in the range of 10-400 nm. 29 (An emulsion is a material in which one liquid is dispersed in another liquid - both mayonnaise and milk are emulsions.) The company refers to the invention as a "microemulsion concentrate" with advantages such as reduced application rate, "a more rapid and reliable activity" and "extended long-term activity." Syngenta , headquartered in Switzerland , is the world's largest agrochemical corporation and third largest seed company. Syngenta already sells pesticide products formulated as emulsions containing nano-scale droplets. Like Bayer Crop Science, Syngenta refers to these products as microemulsion concentrates. For example, Syngenta's Primo MAXX Plant Growth Regulator (designed to keep golf course turf grass from growing too fast) and its Banner MAXX fungicide (for treating golf course turf grass) are oil-based pesticides mixed with water and then heated to create an emulsion. Syngenta claims that both products' extremely small particle size of about 100 nm (or 0.1 micron) prevents spray tank filters from clogging, and the chemicals mix so completely in water that they won't settle out in the spray tank. 30 Banner MAXX fungicide will not separate from water for up to one year, whereas fungicides that contain larger particle size ingredients typically require agitation every two hours to prevent misapplications and clogging in the tank. 31 Syngenta claims that the particle size of this formulation is about 250 times smaller than typical pesticide particles. According to Syngenta, it is absorbed into the plant's system and cannot be washed off by rain or irrigation. 32 EPA position on Nanocides ETC Group is not questioning the Gene Giants' compliance with current pesticide regulations. Pesticides that contain nano-scale active ingredients do not require special regulatory review according to the US Environmental Protection Agency (EPA): a pesticide newly formulated as a nanoemulsion would not require regulatory re-examination since it would not be "a new chemical, new chemical form, nor a `significant' new use." 33 Dr. Barbara Karn at the Office of Research & Development at EPA states that "the pesticide will not behave any differently chemically when in an emulsion." 34 She explains further that "there are no differences in properties of the bulk pesticide solution due to the incorporation of these droplets, and the pesticide chemicals themselves do not exhibit different properties." 3 5 Surprisingly, EPA does not consider Syngenta's nano-emulsions as nano-material based or . EPA's response highlights the lack of clarity regarding what is considered . While the agrochemical industry is exploiting size to change the characteristics and behavior of its pesticides, the EPA concludes that, in the case of nano-emulsions, size does not matter. 27 Email correspondence with Carolin Kranz, BASF, October 27. 2004. 28 WO03039249A3: "Nanoparticles Comprising a Crop Protection Agent." 29 See Bayer Crop Science's US Patent Application no 20040132621, "Microemulsion Concentrates." 30 See Primo Maxx : Primo Maxx 31 See Banner Maxx: Banner Maxx 32 Ibid. 33 Email correspondence with Barbara Karn, EPA, November 1, 2004. 34 Ibid. 35 Ibid.
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