Across the world, an estimated 190 million animals are used for testing and research every year. Many of these animals, including mice, rats, rabbits, monkeys, dogs and fish, are used to explore how human bodies may respond to chemicals. But there are major differences between animals and humans, and immense advancements in technology that hold promise for replacing the use of animals in these tests. Here, Jay Ingram, managing director of chemicals for Humane World for Animals’ global research and testing campaign, explains why new methods hold promise for ending animal testing for chemicals.
Chemicals are everywhere. Whether you're cleaning your home, using personal care products, eating, treating an illness or just existing, you are exposed to chemicals. For some people, the word “chemicals” can spark feelings of unease, as we have often been told that chemicals are harmful. While it's true that there are a number of chemicals that can pose a risk to our health, there are also a large number that are not harmful, and many that help us live better, healthier lives. This makes it all the more important for scientists and regulators to determine if certain chemicals may pose a risk to our health, and at what levels.
Most countries around the world have strict chemical testing regulations that govern the work of scientists and others who are charged with answering these important questions. The main way of determining the potential risk of chemicals has long relied on animal tests, which cause untold suffering as animals are exposed to chemicals being directly poured into their eyes, shoved down their throats, smeared on their shaved skin, injected into them, pumped into the air they breathe, or dosed into every bite of food they eat.
Many chemical regulations were introduced a long time ago, with the rationale at the time that animal testing was the best and only way of determining chemical safety. These regulations often rely on a strict set of animal tests that must be conducted, many of which expose animals to extremely high doses of chemicals, far beyond what we humans would ever experience. For example, tests on rats involved feeding them the human equivalent of 210 grams (over 7 ounces or 16 tablespoons) of salt in a single instance, which would be impossible for a human to ingest at once, no matter how much you love potato chips (a typical serving of chips usually has around 0.2 grams of salt).
Studies have also been conducted where animals have been fed 970 milligrams of sodium dodecyl sulfonate (one of the main ingredients in soaps) every single day. This is the equivalent of humans eating 10 tablespoons of the pure chemical every day for the rest of our lives. The fact that we tend to only use soap on our skin, and don’t eat it, means this amount is very significant.
But because chemicals are everywhere, animal testing is also, sadly, everywhere. But it doesn’t have to be.
We have known for decades that testing on animals doesn't always give an accurate picture of how humans will be affected by chemicals. Our bodies function differently from animals’ in many ways. For example, I make sure my dog, Maisie, doesn't eat any chocolatey treats, as these would likely make her very sick. Even small amounts of chocolate can cause vomiting or diarrhea in dogs, while larger quantities can lead to seizures, irregular heartbeat or even death. By contrast, aside from perhaps contributing to weight gain, chocolate is benign for most humans. And we are exposed to chemicals in different ways and amounts compared to what animals experience in lab tests.
There is a growing social and scientific consensus that there are ethical and practical problems associated with using animals to make determinations and decisions concerning human health. So, as we shift away from animal testing, what methods can be used to determine chemical safety?
Our bodies have a number of structures called receptors, which are like puzzle pieces, and they can become active, or switch off, if a puzzle piece with the right shape comes along. It is these processes that make our bodies work, but it can also trigger harm. Computer software tools make use of huge amounts of human biological information and can accurately predict whether a chemical has the right shape to fit into the puzzle pieces inside our bodies, and if they do, what will happen as a result. These tools are frequently used to determine the safety of cosmetic ingredients and can similarly be used to identify chemicals that have structures associated with DNA damage, which could lead to cancer. They confer a tremendous advantage, allowing scientists to quickly and cheaply screen out potentially harmful chemicals without using animals and with greater benefits to human health and safety. Using computers not only allows us to focus on data that directly relates to people rather than animals but also has the benefit of speed—we can screen chemicals multiple times faster than testing on animals, in some cases getting results in days as opposed to years.
Growing cells in a lab gives us a safe, ethical way of seeing how human cells will behave when exposed to chemicals. We can see the complex processes and how these are affected by chemicals under a microscope. Some scientists are even taking human cells and putting them into complex systems that mimic entire organs in our bodies. These systems are called “organs on chips” and they can replicate organs like a human liver, with all its complex interactions, and put it on a device that is roughly the size of a USB flash drive.
These are powerful advances, as they allow us to predict what will happen without the need to test on a human or animal. This means that the information we get from these tests is more relevant to protecting you and your families than animal tests are, because these tests are based on human biology, and not that of an animal.
Although these scientific technologies have been in place for some time, and are continuously improving, chemical safety laws have been slow to catch up, and regulators are sometimes hesitant to adopt these methods. Many decision-makers are more comfortable with information from animal tests—they know that this information cannot be fully trusted, but the historic use of animals gives them a feeling of confidence because “it’s always been done this way.” Additionally, there is an influential industry built on breeding and supplying a continuous flow of animals for profit.
/The HSUS
Replace animal experiments with sophisticated alternatives
It is long past time for chemical laws across the globe to change and start allowing for more non-animal methods to be used in determining the safety of chemicals. Change can be hard but uptake of more predictive methods of human biology for safety as we continue to pursue even more advanced science, give us a better chance of creating a world where the chemicals we are exposed to are safer for us, and where the suffering that animals endure in labs is put to an end once and for all.
Jay Ingram is managing director of chemicals for Humane World for Animals’ global research and testing campaign.
