18297
Cancer may be induced by viral infection ( EBV , HBV and HPV ) , bacterial infection ( Helicobacter pylori ) , carcinogen , ultraviolet ( UV ) radiation exposure , and genetic mutation .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
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