Tranquilizing polar bears and meat tainted with drugs

This follow-up to my last post has some new information about drug residues remaining in polar bear meat after the animals have been tranquilized.

Regarding the 1-year, Health Canada-imposed ban on eating polar bear meat from animals that have been killed within a year of being tranquilized with the drug Zoletil (aka Telazol), the May 2008 NunatsiaqOnline story that I quoted in my last post said this:

“And Peacock said the GN [Government of Nunavut] is trying to persuade Health Canada to lift its one-year ban on eating the meat of drugged animals.”

A helpful reader brought to my attention the fact that by February 2009, Health Canada had indeed changed their recommendation. She sent me the link to a story run by the CBC (February 6, 2009, Safe to eat meat of tranquillized polar bears after 45 days: Health Canada), which said in part the following:

Health Canada has significantly reduced the number of days northerners should wait before eating the meat of polar bears that were recently tranquillized by researchers.

Previously, Inuit and others who consume polar bear meat were advised to wait one year before eating meat from a bear that had been hit by a tranquillizer dart, a practice commonly used by polar bear researchers.

The federal department has now slashed that wait to 45 days for bears that were subdued by Telazol and Zoletil, two of the most common bear tranquillizers being used.

The department made the decision after looking at research on the drugs.”

…

Alexander said Health Canada looked at existing research, published in 2000, that analyzed muscle, liver and fat from tranquillized bears.

“The study does show that after 24 hours, there will not be much risk associated with consumption of the polar bear meat,” he said.

Health Canada decided on a 45-day wait because the research is very preliminary, he said. The wait time is consistent with U.S. government guidelines, he added. [my bold]

I went looking for confirmation of that CBC story and more background. I looked at the Health Canada website and found nothing about a change in their recommendation regarding wild polar bear meat, not even a press release.

Eventually, I found a “Technical Bulletin” released in 2003 by the Canadian Cooperative Wildlife Health Centre called, “Drug residues in wild meat – addressing a public health concern.” (pdf here). This document explained the 1-year ban on eating polar bear meat from tranquilized animals, based on the study published in 2000 referred to in the CBC story, so it clearly pre-dated the change.

So I went to the Canadian Cooperative Wildlife Health Centre website to see if there was an updated document but found nothing.

Frustrated, I emailed Dr. Marc Cattet, author of the Canadian Cooperative Wildlife Health Centre bulletin, and asked if there was an updated document on drug residues to support the CBC story.

With his permission, I’ve copied his response below (bold is mine):

Hello Susan,

The technical bulletin that you refer to has not been updated, and is unlikely to be updated in the foreseeable future. As for Heath Canada’s or more specifically the Veterinary Drugs Directorate’s (VDD) website, it completely lacks information on the use of drugs in free-ranging wildlife, so it is unlikely that you will find anything at this location.

Nonetheless, I can confirm that I received a letter from the director-general (Dr. Ian Alexander) of the VDD several years ago which stated that the VDD had revised the withdrawal period for the drug Telazol (or Zoletil which is the same drug under a different name) from 1 year to 45 days, and that this revision was applicable only to the use of this drug in bears (polar, black, and grizzly).

However, an important point that is missed by the CBC article is that while some wildlife biologists use Telazol or Zoletil alone to anesthetize polar bears, others use this drug in combination with other drugs to improve the quality of anesthesia (e.g., pain control, relaxation, etc.). In situations where Telazol is used as part of a broader anesthetic drug combination, the withdrawal period is still 1 year. So, not only does an Inuit hunter need to know when a killed polar bear was previously anesthetized, but he/she also needs to know what anesthetic drug was used, before determining the “appropriate” withdrawal period.

I hope this helps.

Best wishes,

Marc
___________________________________
Marc Cattet, DVM, PhD
Canadian Wildlife Health Cooperative
Western College of Veterinary Medicine
University of Saskatchewan

It becomes a little clearer now why some Inuit might not have been as overjoyed with the over-turned 1-year ban on eating meat from tranquilized polar bears as biologists expected. The rapid change in recommendation, made soon after biologists requested it (and without any official documentation), comes across as expedient to say the least.

And it’s important to know that the CBC story left out a critical caveat. As Dr. Cattet put it:

“not only does an Inuit hunter need to know when a killed polar bear was previously anesthetized, but he/she also needs to know what anesthetic drug was used, before determining the “appropriate” withdrawal period.” [my bold]

Not surprisingly, it appears the Inuit objection to tainted meat from mark-recapture work is far from resolved, as the CBC article implies.

And even though Inuit objections to handling polar bears are not primarily about meat tainted with tranquilizers, it might be the main concern for some hunters.

References
Cattet, M. 2003. Drug residues in wild meat – addressing a public health concern. Canadian Cooperative Wildlife Health Centre Technical Bulletin 1-20-2003. Available online, pdf here.