University of British Columbia researchers say a chemical used to produce toilet paper, as well as so-called ‘forever chemicals’ have been found in the carcasses of stranded endangered orca whales offshore of the Canadian province.
Study results, released in December 2022 in an online publication of the American Chemical Society, show that chemical pollutants are prevalent in killer whales. A chemical often found in toilet paper was the one of the most prevalent in the samples studied, accounting for 46% of the total pollutants identified.
The research was a collaborative effort of the UBC Institute for the Ocean and Fisheries, British Columbia Ministry of Agriculture and Food, and Fisheries and Oceans Canada, with researchers analyzing tissue samples from six Southern Resident killer whales and six Bigg’s (transient) whales stranded along the coast of British Columbia from 2006 to 2018.
The study, titled “Emerging Contaminants and new POPs (PFAS and HBCDD) in Endangered Southern Resident and Bigg’s (Transient) Killer Whales: In Utero Maternal Transfer and Pollution Management Implications” was released Dec. 13, 2022, in the society’s publication Environmental Science & Technology.
POPs, or Persistent Organic Pollutants, are toxic substances released into the environment through human activities that adversely affect the health of humans and animals. Many are banned in Canada.
The compound, called 4-nonylphenol or 4NP, is listed as a toxic substance in Canada. Study authors said the compound can interact with the nervous system and influence cognitive function.
“This research is a wake-up call,” said Juan Jose Alava, principal investigator of the ocean pollution research unit at UBC’s Institute of Oceans and Fisheries. “Southern residents are an endangered population, and it could be that contaminants are contributing to their population decline.”
Alava noted that this compound has not been found in B.C. before and it was found in killer whales, which are top predators. “That means the contaminants are making their way through the food system,” he said.
Researchers also looked at the transfer of pollutants from mother to fetus in one Southern Resident whale pair and found that all the pollutants identified were transferred in the womb, and 95% of 4NP transferred from mother to fetus.
“It’s not just the killer whales that are affected,” Alava said. “We are mammals, we eat Pacific salmon as well, so we need to think about how this could affect our health as well as other seafood that we consume.”
4NP is often used in pulp and paper processing, as well as in soap, detergents and textile processing. It can leak into the ocean via sewage treatment plants and industrial runoffs, where it is ingested by smaller organisms and moves up the food chain to reach top predators such as killer whales.
It’s known as a ‘contaminant of emerging concern’ or CEC, which are pollutants found in the environment that are not well-studied and regulated.
“This investigation is another example of an approach that takes into account the health of people, animals and the environment, using killer whales as a case study to better understand the potential impacts of these and other compounds to animal and ecosystem health,” said co-author Stephen Raverty, a veterinary pathologist with the B.C. Ministry of Agriculture and Food.