Is It Time to Replace the 3 R’s?

Over the last four years, Alternatives to Laboratory Animals (ATLA) editor Michael Balls has been reflecting on the 3 R’s concept—reduction, refinement and replacement of animal use—by publishing a series of articles on “The Wisdom of Russell and Burch” in ATLA. We have shared many of these articles with you in Science First, and would like to highlight his final piece in the series for this week’s edition.

Over half a century has passed since W.M.S. Russell and R.L. Burch introduced the 3 R’s in an effort advance animal welfare standards and reduce animal use in science. In many ways, the world of biomedical sciences was very different then compared to today, considering the incredible advancements that have been made in human-relevant, non-animal in vitroand in silico models.

In his final “Wisdom” article, Balls wonders whether we should move on from the 3 R’s concept, as it should have served its purpose by now.

In 2016, he asks, should we still be advocating for a reduction in animal use? Or should this already “be assumed and universally recognized, without the need to campaign for it.” Do we still need to insist that methods be refined to make them more humane? Or should that, too, already by assumed and understood for the sake of animal welfare—and for the sake of science.

Unfortunately, the scientific community is still relying heavily on animal models, “without sufficient recognition of the basic principles of modelling or of the vital importance of the specific factors, lifestyle features and evolutionary adaptations which make animals so very different from ourselves.” Therefore, although reduction of animal use and refinement of methods are important, they are not sufficient, given the evidence that animal models are unfit to serve as human stand-ins.

Ultimately, the overall goal of the research community should be using human-relevant, non-animal in vitro and in silico models as well as in vivo procedures with humans that are safe and ethically acceptable. While to now, we’ve viewed these as replacements to animal use, “it shouldn’t really be about substituting animal procedures at all,” according to Balls.

Emphasizing alternatives as just adjuncts to animal use demeans the huge scientific advancements made in in vitro and in silico animal-free alternatives. These approaches deserve to be recognized on their own merit—for their promise and potential of offering human-relevance and insight in ways that animal models have not, and cannot, provide.

And rather than focusing only on animal suffering as the reason we should change our approach to biomedical research, perhaps we should also be more strongly emphasizing that humans are suffering as a result of inadequacies of the animal models that are used to predict what happens in people.

Balls suggests we now focus on what might be the “greatest gift” that Russell and Burch presented in The Principles of Humane Experimental Technique, which benefits animals and people—the Humanity Criterion—rather than the 3 R’s.

It can be summarized as: If we are to use a criterion for choosing experiments, that of humanity is the best we could possibly invent. The greatest scientific experiments have always been the most humane and attractive, conveying that sense of beauty and elegance which is the essence of science at its most successful.

The research community seems to have accepted the 3 R’s, but unfortunately seems to have trouble actually implementing them. Acceptance of the Humanity Criterion may have a greater impact.

What are your thoughts on this topic? Do you agree with Balls that it is time to say “goodbye” to the 3 R’s and “hello” to humanity? Send your questions and comments to I look forward to hearing from you.

–Dr. Pam Osenkowski, Director of Science Programs

On Replacing the Concept of Replacement
December 2015

In The Principles of Humane Experimental Technique, Russell and Burch gave us the 3 R’s concept—but more important than this was their gift of The Humanity Criterion.

For more information see: ATLA

This entry was posted in News and tagged on February 22, 2016.
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