Scientists Use Honey and Wild Salmon to Trace Industrial Metals in the Enviroment

ScienceMag August 21, 2019

Credit: Dominique Weis

Credit: Dominique Weis

Scientists have combined analyses from honey and salmon to show how lead from natural and industrial sources gets distributed throughout the environment. By analysing the relative presence of differing lead isotopes in honey and Pacific salmon, Vancouver-based scientists have been able to trace the sources of lead (and other metals) throughout the region. Scientists in France, Belgium and Italy are now looking to apply the same approach to measure pollutants in honey in major European cities. The research* is being presented at the Goldschmidt conference in Barcelona.

Scientists have long known that honey bees pick up small amounts of metal elements (i.e., iron, zinc, and pollutants such as lead, and cadmium) when they alight on flowers and leaves. They carry these metals back to the hive where tiny amounts are incorporated into the honey. However, this is the first time researchers have been able to establish clearly the sources of the metals carried by the bees and their products, making them reliable biomarkers for environmental pollution.

“We’ve found that we can let the bees do the hard the work for us: they go to thousands of sites where metal-containing dust particulates might land, then bring samples back to a central hive. From there we can take the honey to have it analysed and begin to identify the source of pollutants like lead” said Ph.D. candidate Kate Smith, part of a team working at the Pacific Centre for Isotopic and Geochemical Research (University of British Columbia).

Once they have sampled the honey gathered by the bees, it is taken to a specialised geochemistry lab to be analysed using a high-resolution ICP-MS (Inductively coupled plasma mass spectrometry) instrument. This allows scientists to distinguish between different types (isotopes) of certain metal pollutants, like lead.

Smith continued, “Looking at the lead isotopic composition of the honey samples, we can tell the difference between honey gathered in the city centre of Vancouver and honey gathered in rural areas. We see that the trace amounts of lead in urban honey samples contain higher 208Pb/206Pb ratios that have no local natural equivalent, indicating that they come from man-made sources like aging city infrastructure and fuel combustion (e.g. cars and ships). Lead ratios measured in rural honey, on the other hand, reflect those of natural sources, like the local geology or particulates from nearby forest fires.”

Presenting the work on salmon, postdoctoral researcher Dr. Miling Li added “This work with honeybees is mirrored in initial findings from shellfish and salmon. Juvenile salmon breed and live in remote freshwater ecosystems in British Columbia, and their lead composition reflects that found in nature, e.g. the nearby Garibaldi volcano range. Adult salmon that forage in the open ocean off the BC coast reveal isotopic compositions consistent with downtown Vancouver honeys. This indicates that Pacific salmons were exposed to lead during their sea life mostly from anthropogenic sources in the Northeast Pacific Ocean.”

Although we can identify the sources of lead, the lead concentrations in both the honey and salmon from Vancouver and the surrounding areas are extremely low and well below the reported world-wide average of lead in honey.

Following the proof of concept work in Metro Vancouver (and similar work in Australia, in Sydney and the site of the vast Broken Hill lead mines, the main source of lead added to gasoline in Europe, Asia and many other places in the world), the UBC team has now developed standardised protocols for measurement of lead isotopes in honey to apply the technique to other cities. Experiments are now being set up in Paris, Brussels, and Piacenza, with interest also coming from the U.S. Simultaneously, the UBC team is confirming the efficacy of the Vancouver honey data by monitoring topsoil and air quality near the hives.

Kate Smith said, “Honey is particularly useful because honeybees can be found pretty well everywhere, so we believe that using honey as a proxy measurement for lead pollution may become an important urban geochemistry and environmental tool. This means we need to make sure that we have a framework that gives results of consistent quality from year to year and city to city. This is what we are now testing.”

Research team leader Professor Dominique Weis said “Urban geochemistry has become an important discipline in understanding the spread of heavy metal pollutants in cities, as long as the natural background is well characterized. Lead isotopic analysis is a standard geochemical method that for decades provided a signal dominated by lead that was used as an additive in gasoline. Honey is an effective biomonitor, and allows us to identify the source of some pollutants even at very low levels; we think that this method could become an internationally accepted way of assessing metal sources and distribution in urban environments”.

Airborne lead pollution varies significantly from area to area. It is found naturally at low levels. Major sources of pollution are metal processing, incinerators, and other industrial processes. Lead in gasoline was banned in the 1990s in North America, which caused a significant decrease in airborne lead levels (98% in the USA). Depending on the level of exposure, lead can have significant health effects**.

Commenting, Professor Mark P Taylor***, Macquarie University, Australia, leader of the Australian group working on honey said,

“This research is emblematic of contemporary science because it touches on two emerging key public interests in an increasingly urbanised world: it examines environmental quality by way of assessing anthropogenic changes to trace element sources in the wider environment and it engages citizens directly through the collection and sharing of honey for geochemical analysis. Nothing could be sweeter for science.”

This is an independent comment; Professor Taylor was not involved in this work.

https://scienmag.com/scientists-use-honey-and-wild-salmon-to-trace-industrial-metals-in-the-environment/?fbclid=IwAR0zbMwynvYS6sGZdYdGS8ZQtkleI8Jw19Ub64BrYyprWC063kdDM_DcUYo

Honey Bees Can Help Monitor Pollution in Cities

Honey from urban bees can tell us how clean a city is and help pinpoint the sources of environmental pollutants such as lead, new University of British Columbia research has found.

In a study published today in Nature Sustainability, scientists from UBC’s Pacific Centre for Isotopic and Geochemical Research (PCIGR) analyzed honey from urban beehives in six Metro Vancouver neighbourhoods. They tested for minuscule levels of lead, zinc, copper and other elements and carried out lead isotope analyses – akin to fingerprinting – to identify where the lead came from.

“The good news is that the chemical composition of honey in Vancouver reflects its environment and is extremely clean,” said Kate E. Smith, lead author of the study and 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.”

Tiny elements, tiny measurements

Metro Vancouver honey is well below the worldwide average for heavy metals like lead, and an adult would have to consume more than 600 grams, or two cups, of honey every day to exceed tolerable levels.

“The instruments at PCIGR are very sensitive and measure these elements in parts per billion, or the equivalent of one drop of water in an Olympic-sized swimming pool,” said Dominique Weis, senior author and director of the institute.

The researchers found the concentration of elements increased closer to areas with heavy traffic, higher urban density and industrial activity such as shipping ports. Places like the city of Delta showed elevated levels of manganese, which could be a result of agricultural activity and pesticide use in the area.

Map of Metro Vancouver, featuring locations of the sampled for this study and possible sources of manmade trace elements.

Map of Metro Vancouver, featuring locations of the sampled for this study and possible sources of manmade trace elements.

Lead fingerprints point to manmade culprits

In the first study of its kind in North America, the researchers also compared the lead fingerprints of the honey to those from other local environmental samples like lichen from around British Columbia, rock from the Garibaldi volcanic belt, sediment from the Fraser River and trees in Stanley Park.

They discovered that the lead fingerprints of the honey did not match any local, naturally-occurring lead. However, the trees in Stanley Park and the honeys from downtown displayed some striking similarities that pointed to potential manmade sources of lead.

“We found they both had fingerprints similar to aerosols, ores and coals from large Asian cities,” said 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.”

Honey is able to provide such localized “snapshots” of the environment because honey bees typically forage for pollen and nectar within a two- to three-kilometre radius of their hives.

“We now have four years of consistent data from Metro Vancouver, which provides a present-day baseline that will allow us to monitor even tiny changes in our environment very efficiently,” said Weis.

Citizen science for communities

The research was carried out in partnership with Hives for Humanity, a local non-profit that creates opportunities for people in Vancouver's Downtown Eastside to engage in urban beekeeping.

"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 team will continue to study how honey analysis might complement traditional air and soil monitoring techniques and test the efficiency of honey as an environmental monitor in other cities.

Find other stories about: Dominique WeisHoneybeesKate E. SmithPacific Centre for Isotopic and Geochemical Research (PCIGR)

https://news.ubc.ca/2019/03/11/honey-bees-can-help-monitor-pollution-in-cities/

It's Earth Day! Let's Join Together and Save the Honey Bee!

Huffington Post  By Margie Alt   April 22, 2015 

Forty-five years ago, the first Earth Day spawned great progress for our air, water and natural areas. The day activated millions of Americans, brought together political leaders of all stripes, and led to the passage of the Clean Water Act, the Clean Air Act, and other bedrock environmental laws. Today, the annual day of action for the environment still inspires more than 1 billion people across the globe.

This Earth Day while celebrating our big accomplishments, we also need to think about something small: the honeybee. Though less than an inch long, the tiny honeybee has major implications for our food supply. In addition to providing us with honey and aiding the beauty of our gardens, honeybees are responsible for pollinating an estimated 71 percent of the world's most widely consumed food crops, including almonds, squash, apples, avocados and more.

Image: FlickrUnfortunately, despite decades of environmental progress, today our food supply and our gardens are in trouble. Bees are dying by the millions. U.S. bee populations have reached historic lows, and we're losing nearly a third of our bee colonies each year -- a rate that more than triples what was once considered normal.

Scientists point to a complex web of factors, including climate change and habitat destruction, to explain the massive collapse of bee colonies here and across the world. But a certain class of insecticides has emerged as a clear culprit. Sharing the same chemical properties as nicotine, neonicotinoids are neurotoxins that can kill bees directly. In addition, these chemicals can disorient them and make it harder for them to get back to their hives. And they can create long-term health and reproductive problems for bee populations.

Image: Waugsberg / Wikimedia Creative CommonsMore than 30 lab studies have shown that these pesticides are a danger to bees. Yet nearly three-quarters of U.S. farms are doused with neonics each year, and up to half of garden plants currently sold in retailers Walmart, Home Depot, and Lowes have been pre-treated with the harmful chemicals.

Slowly, that's beginning to change. The state of Oregon just enacted a limited ban on four types of neonics. Major garden-supply retailers Lowes recently announced it will phase out the use of neonics in its pesticides and garden plants. And earlier this month, the U.S. Environmental Protection Agency took a modest step forward when it announced it would likely ban new uses of the pesticide.

But more must be done. And Earth Day is a perfect day for action.To reverse today's alarming honeybee decline, let's all call for governments and corporations to ban neonics. And if you're planting a garden this spring, you also can help save the bees in your in own backyard. Don't use pesticides or plants and seeds treated with them. And whether your garden spans a flower box or your entire yard, include plants that bees love, such as native wildflowers, flowering herbs, and berries.

This Earth Day, let's certainly celebrate our big accomplishments. But don't forget to think of the little honeybee too. Support efforts to ban neonics, plant a bee-friendly garden, and protect honeybees for the summer and years to come so that on future Earth Days, along with celebrating the Clean Air Act and Clean Water Act we can celebrate the revival of the honeybees.

Read at: http://www.huffingtonpost.com/margie-alt/its-earth-day-lets-join-together-and-save-the-honeybee_b_7112722.html