4942
Four candidate GAC materials were screened in terms of PAH extraction efficiency using single - step 24 - h GAC extractions , with traditional 24 - h Tenax extraction as a reference .
 Chemical: PAH
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: PAH