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The order of concentration of the metals in the tissues is as follows : iron - blood > liver > testes ; zinc - liver > blood > testes ; lead - blood > liver > testes ; copper - testes > liver > blood ; nickel - liver > testes > blood .
 Chemical: iron; Chemical: zinc; Chemical: copper; Chemical: nickel
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: iron; Chemical: zinc; Chemical: copper; Chemical: nickel