3894
We studied lower food webs in streams of two mercury - sensitive regions to determine whether variations in consumer foraging strategy and resultant dietary carbon signatures accounted for observed within - site and among - site variations in consumer mercury concentration .
 Chemical: mercury; Chemical: carbon; Chemical: mercury
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: mercury, carbon, mercury 
Answer:
 Chemical: mercury; Chemical: carbon; Chemical: mercury