2779
Unfortunately , As ( 2 ) O ( 3 ) - treated leukemia patients suffer hepatotoxicity .
 Chemical: As ( 2 ) O ( 3 )
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: As ( 2 ) O ( 3 ) 
Answer:
 Chemical: As ( 2 ) O ( 3 )