Physics The rise of a new generation of radiotherapies means we will soon need much greater quantities of radioactive atoms. That's why companies are scrambling to refine them from all manner of radioactive waste Facebook / Meta Twitter / X icon Linkedin Reddit Email Phoebe Watts for New Scientist; Getty Images “This is Poppy,” says Howard Greenwood, proudly showing me his prize cow. In truth, though, “cow” is charming nuclear research slang. Poppy is a slim glass column filled with radioactive waste that lives not in a pasture, but in a high-security lab. Greenwood and his team here at the United Kingdom National Nuclear Laboratory (UKNNL) near Preston “milk” her for radioactive lead. Why engage in this ticklish business? It’s all to do with the rise of a new generation of radioactive drugs that are showing huge promise as cancer treatments . Radioactivity is hardly new in medicine, but these drugs have a rare power and look set to really take off.…