Study Finds Neonicotinoids Harm Bee Colonies

Harvard research links insecticides to colony collapse disorder

Apr. 18, 2026 at 5:56am

Got story updates? Submit your updates here. ›

A bold, abstract painting in muted earth tones depicts interlocking geometric shapes and waveforms, representing the intricate relationships between insecticides, bee populations, and environmental factors.An abstract scientific visualization explores the complex interplay between neonicotinoid pesticides and the health of honeybee colonies.Spartanburg Today

A recent study from the Harvard School of Public Health found that two widely used neonicotinoid insecticides, imidacloprid and clothianidin, appear to significantly harm honeybee colonies over the winter, especially during colder months. The study replicated previous findings linking low doses of these insecticides to colony collapse disorder, where bees abandon their hives and die.

Why it matters

Bees play a critical role in pollinating crops, and their declining populations have raised concerns about the impact on food production. This study adds to the growing body of evidence that certain pesticides may be contributing to the problem of colony collapse disorder, which has devastated bee populations in recent years.

The details

The HSPH study found that bees in hives exhibiting colony collapse disorder had almost identical levels of pathogen infestation as a control group, contradicting the idea that CCD is caused by reduced resistance to mites or parasites due to pesticide exposure. However, Bayer CropScience has criticized the study, arguing that the levels of neonicotinoids used were unrealistically high and that colony failure would be expected under such conditions.

  • The HSPH study replicated a 2012 finding from the same research group.
  • The new study was published on April 18, 2026.

The players

Harvard School of Public Health (HSPH)

The research institution that conducted the study linking neonicotinoid insecticides to harm in honeybee colonies.

Bayer CropScience

A major agrochemical company that has criticized the HSPH study, arguing the levels of insecticides used were unrealistically high.

Got photos? Submit your photos here. ›

The takeaway

This study adds to the growing scientific consensus that certain pesticides, particularly neonicotinoids, may be contributing to the alarming decline in bee populations worldwide. As bees play a vital role in pollinating crops, further research and action to address this issue is crucial for protecting food security and the environment.