22732
While the highest total nicotine concentrations were observed in twist products , snus and dissolvable tobacco had the highest unprotonated nicotine levels .
 Chemical: nicotine; Chemical: nicotine
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: nicotine; Chemical: nicotine