title: Beta carotene treatment and erythrocytic protoporphyrin levels.
mesh_terms: D002338:Carotenoids / Q000627:therapeutic use*; D004912:Erythrocytes / Q000032:analysis*; D006801:Humans; D008027:Light / Q000009:adverse effects*; D011164:Porphyrias / Q000188:drug therapy*; D011166:Porphyrins / Q000097:blood*; D011524:Protoporphyrins / Q000097:blood* / Q000378:metabolism; D012621:Seasons
chemical_list: D011166:Porphyrins; D011524:Protoporphyrins; D002338:Carotenoids