4076
To better understand the potential exposures introduced by fipronil contamination , we conducted subchronic toxicity tests with larval fathead minnows ( Pimephales promelas ) and waterborne fipronil and its enantiomers and exposed juvenile fathead minnows to fipronil - spiked sediment .
 fipronil, fipronil, fipronil
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 fipronil, fipronil, fipronil