Honey bees may require assistance with maintaining their honeycombs’ cleanliness after extracting honey, and ozone gas fumigation can aid in eradicating pests and pathogens that endanger their health and productivity, according to research from the United States Department of Agriculture (USDA). Ozone fumigation may also be useful in reducing pesticide levels in honeycombs.

Entomologist Rosalind James, leading a two-part study under the Pollinating Insects-Biology, Management, and Systematics Research Unit, operated by the Agricultural Research Service (ARS) of the USDA in Logan, Utah, uncovered the findings. In the first part of her team’s study, published in the Journal of Economic Entomology in 2011, it was demonstrated that ozone gas fumigation of honeycombs at concentrations of 215 – 430 ppm eradicated all life stages of the greater wax moth, contingent on exposure length.

By utilizing 1,500 ppm of ozone, a strongly reactive state of oxygen, spores of the chalkbrood fungus were also eradicated following 24 – 36 hours of exposure. However, the American foulbrood bacterium, another honeybee pathogen, necessitated substantially longer exposure durations and an ozone concentration twice as high.

ozone

Dormant spores of both pathogens have the ability to remain viable for years on beekeeping equipment and in hives, and activate only when optimal conditions arise, attacking the colony’s larvae. Although disinfecting honeycombs using treatments such as methyl oxide and gamma irradiation have demonstrated effectiveness, they are often expensive and impractical, as stated by James. On the other hand, an ozone fumigation chamber is a feasible option for beekeepers to set up on their own.

The second part of the study, published in the Agricultural Science journal in January 2013, discloses the findings of James’ team, highlighting ozone’s potential to disintegrate coumaphos, fluvalinate, and numerous other pesticides that may amass within hives.

To reduce pesticide concentrations in wax and honeycomb samples, greater ozone concentrations and longer exposure durations were necessary. Additionally, the treatments were more effective in breaking down pesticides in new honeycombs (less than 3 years old) compared to older ones (more than 10 years old).