photocarcinogen

photo- +‎ carcinogen

photocarcinogen (plural photocarcinogens)

1. Any substance that becomes a carcinogen on exposure to light.
   • 2009 May 21, Julie Scelfo, “Apply These Product Ratings Generously”, in New York Times‎:

     So I brought it to campus for testing and turns out there was a suspected endocrine disrupter and a photocarcinogen — a chemical that, when exposed to sunlight, has a carcinogenic potential to it.

• photocarcinogenic