Honeybees and their products as potential bioindicators of heavy metals contamination

The concentrations of three representative heavy metals (cadmium, chromium and lead) were measured by atomic absorption spectroscopy in honeybees and in apiary's products (honey, pollen, propolis, and wax). Samples were colle cted from five different sampling points: four from areas surrounding the c ity of Rome, and the fifth in the city center which receives intense vehicu lar traffic. All apiaries employed for this study were specifically constru cted without any metal part in order to avoid the risk of contamination of the assayed materials. Sample collection was conducted over a 3-month perio d (6 samplings for honey and pollen, 3 sampling for propolis and wax, 2 sam plings for honeybees, all of which were collected in duplicate). Experiment al data revealed, in general, statistically significant differences between the background levels of heavy metals recorded from the reference sites an d the levels measured in the site located in the center of the city of Rome . These results indicate that honeybees and, to a lesser extent, some of th eir products (pollen, propolis, wax, but not honey), can be considered repr esentative bioindicators of environmental pollution.