Chemical pollutants, including one used to make toilet paper, have been found in the bodies of two species of killer whale in B.C., one of which is endangered, a new study has found.
Researchers at the University of British Columbia, Fisheries and Oceans Canada (DFO), and the B.C. Ministry of Agriculture and Food analyzed tissue samples from six southern resident killer whales and six Bigg’s (transient) orcas that were stranded on the B.C. coast between 2016 and 2018.
The toilet paper pollutant, called 4-nonylphenol (4NP), accounted for 46 per cent of all pollutants identified, according to study co-author Juan Juan José Alava.
“This research is a wake-up call,” the UBC Institute for the Ocean and Fisheries investigator said in a Thursday news release.
“Southern residents are an endangered population and it could be that contaminants are contributing to their population decline. We can’t wait to protect this species.”
The study, published in the January edition of Environmental Science and Technology, is the first to find 4NP in killer whales. The substance, often used in pulp and paper processing, soap and detergent, can leak into the ocean via sewage treatment plants and industrial runoff, UBC said in the release.
The research found more than half of the pollutants in the whales’ tissue belonged to a group of compounds known as ‘forever chemicals,’ which take a long time to disappear from the environment. Some are harmful to both human and animal health and many are banned in Canada.
The most common one detected in the test whales was 7:3-fluorotelomer carboxylic acid, which is not restricted in Canada. One of its possible parent ingredients, however, is on a list of toxic substances, reads the Thursday release.
“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,” Alva said.
“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,” added co-author Stephen Raverty, a veterinary pathologist with the B.C. Ministry of Agriculture and Food.
The team also found the pollutants were transferred from mother to baby in a pregnant southern resident killer whale whose tissue was analyzed.
Researchers are now calling on governments to help protect the endangered species by stopping the production of chemicals of concern, such as 4NP, nationwide.
At last count, there were fewer than 75 southern resident killer whales left in the wild.