5710
In two experiments , rainbow trout were injected intraperitoneally with 0 , 10 , or 100 mg / kg of naphthenic acids , and sampled after 5 or 21 d .
 naphthenic acids
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 naphthenic acids