20762
METHOD : Twenty ecstasy - polydrug users , 20 non - ecstasy - polydrug users and 20 drug - na i ve controls were recruited .
 Chemical: ecstasy; Chemical: ecstasy
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: ecstasy; Chemical: ecstasy