Does chest x rays causes cancer?

No. You would need thousands of chest X-rays to have enough radiation exposure to cause cancer or any other health problem.

One or two x-rays would not alter your baseline risk of cancer. 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. Wish you good health!