5175
Based on the collective evidence , the authors estimated that risks were posed by sediment PCB concentrations greater than 77 ng / g dry weight for black guillemots and 750 ng / g dry weight for shorthorn sculpins .
 Chemical: PCB
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: PCB