Chemicals from wildfire smoke found in whales: UBC research

Research out of UBC has made a new disturbing discovery. Chemicals from oil emissions and even wildfire smoke have been found in Southern Resident and Bigg’s killer whales.

The study says it is the first to discover polycyclic aromatic hydrocarbons (PAHs) in the whales off the coast of B.C. PAHs are found in coal, oil, and gasoline, and come from several sources, including spills, burning coal, and wildfire smoke, researchers explain.

“There is a process, a pathway mechanism in the atmosphere called the long-range transport … So, eventually, these particles, this organic matter, this particulate matter, all this smoke basically carrying all these chemical contaminants, will deposit via dry deposition or wet deposition — basically the rain,” said senior author Dr. Juan José Alava, who is the principal investigator of the UBC Ocean Pollution Research Unit.

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The study, which found the chemicals in muscle and liver samples, also documented in utero transfer of the substances from mother orcas to fetus.

Highlighting the need to ‘phase out fossil fuels

Alava says the findings are more evidence that policy makers need to hear.

“These iconic, majestic, gentle animal — I call them the canaries in the coal mine — are telling us that something is wrong in the environment, that it’s contaminated, and that this is a time to really look for prevention measures,” Alava told CityNews.

“Our data, basically, is to inform policy, it’s basically data that can be used by decision makers to really start implementing mitigation, prevention measures. That means, also, the need for transitioning away and phase out fossil fuels.”

Alava, who is also an adjunct professor at Simon Fraser University, says killer whales are apex predators, adding their health is vital to the health of marine biodiversity.

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The study says samples from six Bigg’s and six Southern Resident killer whales that were “stranded in the northeastern Pacific Ocean between 2006 and 2018” were analyzed as part of the work.

“By using some combination of ratios … we were able to infer and elucidate that the Southern Resident killer whales are basically more exposed to what we call petrogenic sources,” Alava explained, noting these are petroleum-based chemicals.

Tissue samples from the Transient Bigg’s whales contained chemicals from burning coal and vegetation, and from wildfires. Alava says the difference between the Transient and Southern Resident whales likely comes down to where they spend most of their time — Bigg’s whales move from California to Alaska, whereas Southern Resident whales tend to stick close to more urban environments that are more polluted.

Half of the PAHs tested for were found in at least 50 per cent of the samples taken, researchers explain, adding C3-phenanthrenes/anthracenes, a PAH derivative, “accounted for 33 per cent of total contamination across all samples.”

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“These forms of PAHs, known as alkylated PAHs, are known to be more persistent, toxic, and to accumulate more in the bodies of organisms or animals than parental PAHs,” the study explained.

Alava says the research supports discussions at COP28, the recent United Nations Climate Change Conference, about the need to work to reduce and, eventually, eliminate fossil fuel use.