Propolis is a reddish brown wax-like resinous substance collected by bees from tree buds and used as a cement and to seal cracks or open spaces in the hive. Honeybees will use propolis to attempt to seal any gap inside the hive that is smaller than the bee space, approximately 6.3 mm.

Traditionally, beekeepers assumed that bees sealed the cracks and joints of the beehive with propolis to prevent drafts during the wintertime. More recent research suggests that bees not only survive, but thrive with increased ventilation during the winter in most temperate regions of the world. Propolis is now thought to:

1. reinforce the structural stability of the hive
2. reduce vibration
3. make the hive more defensible by sealing alternate entrances

Bees will also sometimes use propolis to keep the hive hygenic. Bees normally carry waste (dead larva, etc.) out of and away from the hive. However, if a mouse chews its way into the hive for a winter nest and dies, the bees won't be able to move it out through the hive entrance. They have instead been known to seal the carcass in propolis, effectively mummifying the mouse.

Propolis is marketed by health food stores as a traditional medicine, and for its claimed beneficial effect on human health. However, research is inconsistent on its efficacy. Claims have been made for its use in treating allergy; it may stimulate the immune system, but some warn that it should not be taken if the user is likely to have severe allergic reaction to bees.

Composition

Propolis has approximately 50 constituents, primarily resins and vegetable balsams (50%), waxes (30%), essential oils (10%), and pollen (5%). Propolis is used by music instrument makers to better show the wood grain. It is a component of Italian varnish and was reportedly used by Stradivari.

See also

• Discussion of bee space in the "Langstroth" section of beehive.

External links

• http://www.mycustompak.com/healthNotes/Supp/Propolis.htm
• WHO warns adverse effects of Propolis extract: blood in stool
• Contact dermatitis and other skin conditions in instrumental musicians

Published online 2004 April 16