Update 5-exposure-ionizing-radiation.md
Update 5-exposure-ionizing-radiation.md

Resolved:
https://github.com/department-of-veterans-affairs/vets-website/issues/527
https://github.com/department-of-veterans-affairs/vets-website/issues/519
department-of-veterans-affairs/vets-website,department-of-veterans-affairs/vets-website