The hon. Gentleman makes an important point. I am not suggesting that the current system is 100% perfect at all. In fact, I made it clear in my earlier comments that, often, animal models are not perfect predictors—he is right to say that. But it is equally the case that, without the animal models, an awful lot of drugs would be taken forward into humans with hugely damaging side effects and no benefits. The point is not that once something has been through animal testing it is a perfect drug. Going through animal testing prevents exposing humans to potential drugs that are simply unsafe. It is not perfect, but that is the situation. He is right to point out that animal testing itself is not a guarantor of efficacy.
The truth, sadly, is that without testing of medicines using animals at the moment, we would not know whether medicines are safe or effective for use in humans or animals, and that would limit the availability of medicines to treat disease and of chemicals that could be used for a wide range of purposes in many industries. There is a human health and safety part to this. In order to protect workers in the chemical and agricultural industries, we need to ensure that we understand any toxicity of those chemicals before they are used. Without the testing of chemicals on animals, where no alternative methodologies are available, we would not know what hazards they present. Many products that are not safe in humans or the environment are detected through animal testing, thus avoiding harm downstream.