Honey from city bees can be used to trace environmental pollutants
Researchers at the University of British Columbia (UBC) have discovered that honey samples can be used to measure environmental pollution. When bees hunt for pollen and nectar near their hives, they pick up trace amounts of elements such as lead. As a result, these elements can be detected in the honey produced by the bees.
Scientists at the UBC’s Pacific Centre for Isotopic and Geochemical Research (PCIGR) analyzed honey samples from six Metro Vancouver neighborhoods, testing for lead, zinc, copper, and other elements. In addition, the team used lead isotope analyses to pinpoint where the lead originally came from.
“The good news is that the chemical composition of honey in Vancouver reflects its environment and is extremely clean,” said study lead author Kate E. Smith, who is a PhD candidate at PCIGR. “We also found that the concentration of elements increased the closer you got to downtown Vancouver, and by fingerprinting the lead we can tell it largely comes from manmade sources.”
The experts found that the honey collected in Metro Vancouver was well below the worldwide average for heavy metals like lead. For example, an adult would have to consume more than two cups of honey every day to exceed safe lead levels.
The study also revealed that the concentration of lead increased in areas with heavy traffic and industrial activity, while levels of manganese appeared to increase near areas with more agricultural activity and pesticide use.
The isotope analysis showed that the lead could not be traced to any local, naturally-occurring sources.
“We found they both had fingerprints similar to aerosols, ores and coals from large Asian cities,” said study senior author Dominique Weis. “Given that more than 70 per cent of cargo ships entering the Port of Vancouver originate from Asian ports, it’s possible they are one source contributing to elevated lead levels in downtown Vancouver.”
The research was carried out in partnership with Hives for Humanity, which is a local non-profit that creates urban beekeeping job opportunities for people in Vancouver’s Downtown Eastside.
“One of the exciting parts of this study is that it bridges science with community interests,” said Smith. “Honey sampling can easily be performed by citizen scientists in other urban centres, even if they lack other environmental monitoring capabilities.”
The study is published in the journal Nature Sustainability.
Image Credit: Hives for Humanity