22085
Little is known in terms of multi - matrix cytochrome P450 activity induction under repeated oral exposure to planar halogenated and polycyclic aromatic hydrocarbons ( PHH , PAH ) .
 Chemical: halogenated and polycyclic aromatic hydrocarbons; 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: halogenated and polycyclic aromatic hydrocarbons; Chemical: PAH