18652
The effect of developmental exposure to chlorpyrifos ( CPF ) on hippocampal neurogenesis was examined in male mice after maternal dietary exposure to CPF at 0 , 4 , 20 , or 100ppm from gestation day 10 to postnatal day ( PND ) 21 .
 Chemical: chlorpyrifos; Chemical: CPF; Chemical: CPF
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: chlorpyrifos; Chemical: CPF; Chemical: CPF