A new study from the University of Guelph, located in Canada, confirms that sub-lethal doses of certain pesticides cause harm to honeybees. The scientists say that neonicotinoid pesticides, or “neonics,” actually interfere with the bees’ ability to self-groom and increases their risk of succumbing to a deadly mite infestation.

Published in Scientific Reports, the researchers looked at the effects of clothiandin, a commonly used neonic, on bee grooming behavior. What they found was that low-level exposure to the neonic caused the bees to stop grooming themselves properly.

For bees, poor self-grooming practices can be fatal, as it leaves them susceptible to varroa mites — and these mites can carry deadly viruses