Table 1.

External Fragile Site-Inducing/Enhancing Agents.

Agents	Applications	References
Dietary and environmental
Atenolol	Hypertension drug	[74]
Benzene	Cigarette smoke, gasoline, pesticides, food, water	[75]
Caffeine	Dietary agent	[76, 77]
Carbon tetrachloride	Refrigerants, pesticides	[75]
Cigarette smoke	Dietary and environmental agent	[78, 79]
Diethylnitrosamine	Cigarette smoke, pesticides, food, beverage	[75]
Dimethyl sulfate	Dyes, drugs, perfumes, pesticides	[75]
Ethanol	Dietary agent	[80, 81]
Hypoxia	Low oxygen, tumor microenvironment	[82]
Pesticides	Dietary and environmental agent	[83–85]
Chemotherapeutics
5-Azacytidine	Myelodysplastic syndrome, leukemia	[75]
Actinomycin D	Sarcoma, Wilms' tumor, germ cell, testicular, Melanoma, neuroblastoma, retinoblastoma	[75]
Bleomycin	Squamous cell, melanoma, sarcoma, testicular, Hodgkin's and non-Hodgkin's lymphoma	[75]
Busulfan	Chronic myelogenous leukemia	[75]
Camptothecin	Colon, rectal	[86]
Chlorambucil	Chronic lymphocytic leukemia, Hodgkin's and non-Hodgkin's lymphoma, breast, ovarian, testicular	[75]
Cytosine arabinoside	Leukemia, lymphoma	[75]
Floxuridine	Colon, kidney, stomach	[75]
Methotrexate	Breast, head and neck, lung, stomach, esophageal, sarcoma, non-Hodgkin's lymphoma, acute lymphoblastic leukemia	[75]