Boreiko, C J.; Abernethy, D J.; and Frazelle, J H., Detection of carcinogens which initiate the process of c3h/10t1/2 cell transformation. Abstr. (1982). Subject Strain Bibliography 1982. 2148. https://mouseion.jax.org/ssbb1982/2148
Hi Sue, The ringing in the ears is called Tinnitus. It can be a side effect of medications (check what you are taking) or for me, it can also be a sign that a migraine is on the way. It could also mean a number of many other things, depending on other symptoms you may have.
Ringing in the ears: Medically called tinnitus, can be due to many causes including ear infections, fluid in the ears, Meniere syndrome (the combination of tinnitus and deafness), some medications such as aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs), aging, and ear trauma (such as from the noise of planes, firearms, or loud music ...