16376
However , since 2NA per se is not carcinogenic and main downstream metabolites of 2NA have not been found in urine so far , it remained uncertain if 2NA derived from P2NA dephenylation is further activated to carcinogenic downstream metabolites .
 Chemical: 2NA; Chemical: 2NA; Chemical: 2NA; Chemical: P2NA
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: 2NA; Chemical: 2NA; Chemical: 2NA; Chemical: P2NA