Yes, retinol serum can be vegan and animal-free. There are many brands that make retinol serum that is made without animal ingredients and has not been tested on animals. It's important to read labels carefully and make sure the product is from a trusted and ethical brand. When you choose a vegan and animal-free retinol serum, you can be sure that you are using a high-quality product that is safe for both your skin and the environment.