14870
Pregnant rats were orally exposed to PCB52 ( 6 dose groups , total dose of 0 - 3000mg / kg body weight ) or PCB180 ( 6 dose groups , total dose of 0 - 1000mg / kg body weight ) .
 Chemical: PCB52; Chemical: PCB180
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: PCB52; Chemical: PCB180