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The calculated trophic transfer factors ( TTFs ) of the metals in different prey varied and were the highest for clams and mussels prey , indicating that metal bioavailability from these prey was higher than that from barnacles and oysters .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
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