Vegans: Are you sure the vegetables you eat haven't been fertilized?

Yes, I am sure about my produce-I grow my own, and know exactly whats in or on it. I use an indoor hydroponic garden with grow lights for year round gardening, and plant outdoors during the season. I fertilize with compost made from veggie scraps that I save and compost. Its amazing how many uses the industry finds for using dead animal parts, isnt it? Anything not rendered for food goes into pharmaceuticals or other products.