New research reveals that bumblebees collect up to seven times as much toxic heavy metal as honeybees, even when foraging in exactly the same environment.

The study, published in the journal Ecological Entomology, was led by Dr Sarah Scott, who carried out the research while at Cambridge and is now based at Newcastle University, with Selwyn Fellow Professor Lynn Dicks from the Department of Zoology as senior author.

Researchers collected pollen samples from apiaries in Cambridgeshire and measured concentrations of arsenic, cadmium, chromium, cobalt, lead and tin in both pollen and adult bees. Despite honeybee and bumblebee colonies foraging in the same landscapes, bumblebees collected pollen with between two and seven times the level of heavy metals, and accumulated around three times greater concentrations of heavy metal in their bodies.

The differences are likely down to a combination of foraging behaviour and physiology. Honeybees travel further, up to 10 km from the colony, and forage across a wider range of flowers, diluting any contamination. Bumblebees stay closer to their nest, typically no more than 1.5 km, and are hairier, making them more likely to pick up metal-containing dust and particles.

Professor Dicks said: "Even in areas that we usually consider safe or lower risk for heavy metals, typically rural areas away from industrial or mining areas, bees can pick up toxic metals. Bumblebee colonies tend to have fewer workers available to perform tasks, so the loss of individuals can have a big impact on overall colony function."

The research was funded by the Royal Society.

Read the full research paper here: Scott, S et al. Eusocial bee species are exposed to different toxic element profiles despite foraging within the same landscape. Ecological Entomology; 16 Jun 2026; DOI: 10.1111/een.70108

Read the full University of Cambridge news release here.