Iris Borer Deterrent

The active ingredient in Garden Shield^TM Iris Borer Deterrent is Methyl Nonyl Ketone (MNK). This substance was used in the 1950’s as an ulcer drug and is used today in many cosmetics and perfumes to enhance certain aromatic notes. MNK is also well known for its broad spectrum repellent properties and works effectively to repel both insects and warm-blooded mammals. Unfortunately it has a half-life of only 12 hours and is rapidly degraded by ultraviolet light, oxidation and bacterial action; eventually breaking down into carbon dioxide and water. Until Garden Shield’s^TM research innovation, no one had found a practical way to increase both its half-life and its adhesion to plant surfaces. With MNK, these were not easy challenges to overcome, but overcome them we have!

MNK exhibits no toxicity via the oral or inhalation routes. In studies, pure MNK produced slight dermal and eye irritation, and is a weak dermal sensitizer. At 100% concentration the No Observed Effect Level was greater than 300 mg/kg/day. Garden Shield^TM Iris Borer Deterrent contains only 1.9 percent MNK.

MNK is relatively immobile in soil and has a low potential to leach into ground water or move off site into surface water. MNK was found to be relatively immobile in sodium azide-sterilized sandy loam, clay loam, sand, and silt loam soils. It does not hydrolyze.

Pure MNK is essentially non-toxic to birds on an acute oral and subacute dietary basis, and moderately toxic to both cold and warm water fish. Note however that it is highly toxic to aquatic invertebrates; therefore do not to apply to open water.

Due to the repellent nature of the product, risk to non-target terrestrial species is not likely. In addition, non-target aquatic species exposure is unlikely because this chemical is neither persistent nor mobile in the environment and associated use patterns.