Algemeen

The use of imidacloprid as a systemic insecticide to trees is associated with adverse effects on non-target insects and earthworms

Imidacloprid can be applied as a systemic insecticide to trees by direct stem injections or by soil injections and drenches, and be indirectly introduced to aquatic systems via leaf fall or leaching, which may pose a risk to natural decomposer organisms. When applied directly to aquatic microcosms to simulate leaching from soils, imidacloprid was shown to be highly toxic to aquatic insects. Imidacloprid at realistic field concentrations in maple leaves had adverse effects on aquatic insects and earthworms. Imidacloprid at realistic concentrations in leaves can inhibit leaf litter breakdown through adverse effects on decomposer invertebrates. When imidacloprid is applied as a systemic insecticide to the soil around trees it may cause adverse effects on earthworms.

Environmental Fate of Imidacloprid

There are concerns regarding the long-term environmental fate and environmental persistence of the widely used insecticide imidacloprid. The 2005 sales figures for insecticides in Germany show not only that imidacloprid is one of the most widely used active ingredients, but also that this compound is more toxic to honey bees, more persistent in soil with a higher leachability than most other insecticides used in that country. The neonicotinoid insecticides clothianidine and thiomethoxam have similarly unfavourable properties.