Save the Critters: Reducing Animal Testing in Research

By Jennifer Norcross

Sunscreen, cough syrup, antibiotics, insulin: have you ever thought about how products like these came to be used by people? They may have been tested on animals first. However, scientists are now trying to reduce the amount of animal testing needed before a drug or medicine is considered safe and is given to patients and consumers.

One important reason for researchers to move away from using animal models in a study is that the results may not always be the same when compared to a human study. For example, smoking does not cause cancer in mice and rats, but scientists discovered that cigarettes do cause cancer in people.

The Three Rs: Replacement, Reduction, and Refinement

Researchers have come up with a few different methods, known as the three Rs, that can help reduce animal testing for new products.

Replacement occurs when compounds are tested on something other than an animal. This can be done using human stem cells or surgically removed tissue from a donor. Another way is to use an organ on a chip: cells can be grown on a microchip into a cluster (organoid) that mimics a real human organ, like a lung or a liver.

Reduction is when scientists use fewer animals in a study. This can include using AI to search through thousands of pages of existing scientific literature to find previous results about the specific chemical being tested (thereby requiring fewer new experiments on animals) or to eliminate substances that have already been proven ineffective in other studies.

Refinement is making sure the animals in a study are as comfortable as possible. This includes providing them with an appropriate habitat, food, and socialization, and treating them kindly. One example of the refinement method is giving an animal anesthesia before taking a tissue sample, the same as a person having an operation.

Are Non-Animal Alternatives Better?

These methods are promising because they’re reducing the number of animals being used for research and they’re often more effective in confirming product safety. For example, when studying human pregnancy, animal tests of chemicals that could potentially harm a developing baby only show problems for about 60 percent of dangerous substances. But tests using human stem cells have shown far greater sensitivity (93 percent) when detecting substances known to cause developmental problems after the child is born.

Because these alternatives are effective, it’s possible for researchers around the world to use fewer animals in their studies. This will allow the scientific community to continually discover new medicines, while also being considerate of other species.