12701
Based on the relationships among Cd and Zn concentrations in water , sediment , and biota , the authors conclude that Cd and Zn in crabs primarily derived from sediment exposure .
 Chemical: Cd; Chemical: Zn; Chemical: Cd; Chemical: Zn
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: Cd; Chemical: Zn; Chemical: Cd; Chemical: Zn