What bees reveal about environmental contamination through honey

What bees reveal about environmental contamination through honey
by Clarence Oxford
Los Angeles CA (SPX) Dec 09, 2024

Honey, long prized for its natural sweetness, can also serve as a lens into environmental health, according to a new study by Tulane University. The research shows that bees inadvertently collect environmental pollutants, which become detectable in the honey they produce. This discovery provides insights into regional pollution patterns across the United States.

Published in Environmental Pollution, the study analyzed 260 honey samples from 48 states, examining them for six toxic metals: arsenic, lead, cadmium, nickel, chromium, and cobalt. Although none of the samples exceeded safety thresholds for daily consumption (based on one tablespoon per day), the study revealed notable regional variations in toxic metal concentrations. For instance, honeys from the Pacific Northwest - specifically Oregon, Idaho, Washington, and Nevada - contained the highest levels of arsenic. Meanwhile, cobalt concentrations were highest in the Southeastern states, including Louisiana and Mississippi, and elevated lead levels were found in the Carolinas.

"Bees act as passive samplers, picking up contaminants from the air, water and plants while foraging. These contaminants end up in honey, offering us a snapshot of an area's environmental pollution," explained lead author Tewodros Godebo, an assistant professor of environmental health sciences at Tulane University's Celia Scott Weatherhead School of Public Health and Tropical Medicine.

This nationwide study, the first of its kind, relied on single-source honeys clearly labeled with their place of origin. Researchers suggest that historical pesticide use, industrial pollution, and legacy contamination from leaded gasoline and paint could explain the elevated levels of specific metals in certain regions. For example, Washington's high arsenic levels (170 ug/kg) might stem from historical agricultural practices, while North Carolina's and South Carolina's elevated lead concentrations (451 ug/kg and 76.8 ug/kg, respectively) could be linked to soil pollution or lead-based aviation fuels.

Further investigation is needed to definitively link the pollution patterns in honey to their sources. "The environment can have more of these metals than what shows up in bees' honey," Godebo noted, suggesting that honey provides only a partial view of regional contamination.

"What we found is that this appears to serve as a good proxy for uncovering regional contamination patterns," Godebo said. "But there's a lot we may still learn from bees about what pollutants are present in the environment and how those relate to nearby community health outcomes."

The study underscores the potential for honey to serve a dual purpose: as a natural food product and as a tool for monitoring environmental pollution. Researchers hope these findings will encourage further exploration into the relationship between toxic metal pollutants, their environmental sources, and public health implications.

Research Report:Metals in honey from bees as a proxy for environmental contamination in the United States