This is a laboratory toxicity study of two neonicotinoids (aka “neonics”)—Syngenta’s thiamethoxam and Bayer’s imidacloprid—and not indicative of real-world exposure. Some areas of concern include:

• Beneficial insects were only allowed to feed on contaminated honeydew. In the real world, there would be other food sources, such as nectar and honeydew from untreated plants.
• Movement of neonics in plants is dependent on the soil type and tree size. This study used small (1 meter high), potted Clementine trees in a greenhouse setting. Therefore, results of this study might not be representative of mature trees grown in more natural soils.
• In the thiamethoxam-treated plants, the amount of honeydew collected from the mealy bugs was much lower than in the control and imidacloprid treatments. This indicates thiamethoxam may be more effective on pest species, such as mealy bugs, and mean less honeydew in crops treated with thiamethoxam and, ultimately, less exposure to non-target organisms.

Neonics are rigorously tested before going to market to ensure they can be used safely and effectively. In the case of Syngenta’s thiamethoxam, more than 1,600 studies have been conducted in support of its safe use, including humans, wildlife and the environment.

Neonics are an essential tool for farmers because they provide selective control of damaging pests and help ensure beneficial insects remain available to keep other potential pests in check. Without neonics, growers would be forced to rely on a few older classes of chemistry that are less effective at targeting pests and require more frequent applications.