Toys that emit sudden loud sounds could harm the ears of kids, warn scientists. This is because the small muscles and neural circuitry that are built into our ears to help protect them from noise cannot act fast enough to save them from very sudden sounds, said Bradford C. Backus of the University College London's Ear Institute. The researcher tested the noise made by toys, including toy guns, a toy phone, toy cars and those that play nursery rhymes or the alphabet, reported the online edition of health magazine WebMD.