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Formaldehyde gave the strongest response ; a total of 66 genes were more than 1 . 5 - fold differentially expressed mostly involved in apoptosis and DNA damage related processes , followed by acetaldehyde ( 57 genes ) , hydroquinone ( 55 genes ) and nicotine ( 8 genes ) .
 Chemical: Formaldehyde; Chemical: acetaldehyde; Chemical: hydroquinone; Chemical: nicotine
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: Formaldehyde, acetaldehyde, hydroquinone, nicotine 
Answer:
 Chemical: Formaldehyde; Chemical: acetaldehyde; Chemical: hydroquinone; Chemical: nicotine