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In this study , we showed that IKK - beta contributed to hydrogen peroxide ( H ( 2 ) O ( 2 ) ) - induced cell death independent of the NF - kappa B pathway .
 Chemical: hydrogen peroxide; Chemical: H ( 2 ) O ( 2 )
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: hydrogen peroxide, H ( 2 ) O ( 2 ) 
Answer:
 Chemical: hydrogen peroxide; Chemical: H ( 2 ) O ( 2 )