Im 47 and i have hydronephrosis and from oct 2021- april 2022 ive had 7 ct scans.6 of then were abdomen/pelvis w/o contrast and 1 of them was head or brain w/o contrast.should i be worried about too much radiation exposure?would that cause the c-word?

There may be a marginal, increase in risk of cancer from radiation, benefit of CT exceeds the risk. You can reduce your risk of cancer by adopting healthy habits: Eat a mostly vegetarian diet, avoid alcohol, tobacco and street drugs, avoid excessive exposure to sun, maintain healthy weight, get HPV vaccine, exercise 30 minutes each day, drink enough water so your urine is mostly colorless.

CT scans should be done after great thought and only if other less invasive methods wont give the desired answer. So less is better. They are also done with a much lesser dose of radiation now. Your exposure is well short of the 'C'-word But next time discuss it with your MD when one is ordered.