“…Paradoxically, health risk among students, instructors, and all involving parties via skin contact and inhalation becomes the major disadvantages of Fd. The immediate symptoms include irritation of the throat, nose, eyes, and skin [ 3 , 8 , 14 , 15 , 18 , 19 , 21 , 22 ]. The United States Environmental Protection Agency [ 6 ] and International Agency for Research on Cancer [ 11 ] classified Fd as a human carcinogen, such as nasopharyngeal cancer, ocular melanoma, lung cancer, brain cancer, and leukemia [ 2 , 5 , 7 , 26 ].…”