Review says imidacloprid insecticide minimal risk to aquatic invertebrate communities

Bayer Crop Science recently said a new ecotoxicological review and risk assessment found that imidacloprid, one of the most widely used insecticides because of its effectiveness and its relatively favorable human and environmental safety profile, is a minimal risk to sensitive aquatic invertebrate communities.

This is also good news for other wildlife, such as birds and fish, since these insects are an important part of their diet, officials said.

The review details the body of research, the careful selection and use of the best available data and the probabilistic risk assessment. The probabilistic approach better predicts the effects to sensitive species, the relevant exposures and the potential risks to aquatic invertebrate communities in terms of the actual label use directions and the natural environment for these crops and treated landscapes.

“Laboratory testing is necessary to establish toxicity endpoints for a wide range of organisms, however such studies have unrealistic exposure conditions which often lead to overestimated toxicity," Dr. Dwayne Moore, senior vice president and scientist at Intrinsik Environmental Sciences Corp., one of the researchers involved in the review, said. "Fortunately, we had data from many higher-tier mesocosm studies for imidacloprid, which is almost unprecedented.”

“We conducted 30-year simulations based on realistic, but conservative, assumptions and found that aquatic communities are unlikely to be at risk from acute or chronic exposures to registered uses of imidacloprid,” Moore said. “In fact, risks were de minimis, the lowest possible category, for all crop and noncrop uses.”