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written by
Andrea Levey

Perspectives from Product Development

Recent U.S. Department of Agriculture data shows farms and ranches in the U.S. produced and sold $7.6 billion in certified organic commodities in 2016, up an impressive 23% from 2015. The number of certified organic farms in the U.S. increased 11% to 14,217, while certified acres increased 15% to 5 million during the same time period. These realities put added pressure on many mosquito abatement districts to work with products that are more environmentally compatible with organic production.

This was the driver behind the development of our Merus® adulticide, which uses natural pyrethrins, a botanical insecticide and the only OMRI-Listed active ingredient currently approved for use in adult mosquito control products. Natural pyrethrins are imported from Africa, where flowers from pyrethrum-producing plants are picked by hand, sun dried and sent to a processing plant for extraction of the active ingredient.

And what we initially delivered back in 2013 – Merus 1.0, the first OMRI Listed adulticide for wide area mosquito control – is a product we’ve continued to refine to improve affordability and user experience. For our product development team, the evolution of the Merus adulticide has been an exciting journey, with the newest formulation, Merus 3.0.

The Making of Merus 3.0

The work we do at Clarke is ultimately to improve quality of life and protect public health, so not only do our products need to work, they need to be accessible to use. With the newest Merus 3.0 product, we were challenged to continue improving affordability without sacrificing efficacy. Our team said, “OK, we can do this one or two ways: change the solvent, or reduce the amount of active ingredient.” Although the active ingredient is the primary driver behind the product’s cost, we knew that playing with the active ingredient would ultimately compromise efficacy, so we focused our efforts on the carrier complex.

An exhaustive screening process of the solvents on the EPA’s approved list of inert ingredients for organic products helped us identify a short list of viable options. We tested and rated them according to multiple characteristics, including volatility, density, solubility, compatibility and storage stability, among others.

The solvent we ultimately choose was one we’d never worked with before. We also tried to think more holistically about the product’s end use and application methods, in an effort to strike the right balance between the formulated product’s density and evaporation rate. At the sweet spot, the product’s application rate and efficacy are optimal.

The newest Merus 3.0 product meets all the criteria for a Clarke NextGen mosquito control product – using a naturally derived active ingredient in a formulation with no petroleum distillates, giving the product a softer, greener chemistry profile. But more importantly, Merus 3.0 works against disease-carrying mosquitos and we continue to improve the affordability of the product, opening up its access for mosquito abatement districts and municipalities where OMRI Listed and NOP Certified options are prioritized or required.