14894
Combined effects of organochlorine pesticides heptachlor and hexachlorobenzene on the promotion stage of hepatocarcinogenesis in rats .
 Chemical: organochlorine; Chemical: heptachlor; Chemical: hexachlorobenzene
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: organochlorine; Chemical: heptachlor; Chemical: hexachlorobenzene