24957
Current knowledge of the physiology and phylogeny of polycyclic aromatic hydrocarbon ( PAH ) degrading bacteria often relies on laboratory enrichments and isolations .
 Chemical: polycyclic aromatic hydrocarbon; 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: polycyclic aromatic hydrocarbon; Chemical: PAH