8581
The catadromous European eel ( Anguilla anguilla L . ) has suffered a dramatic decline in recruitment for three decades , necessitating a thorough assessment of the transcriptional effects of environmental pollutants on resident and migrating eels in natural systems .
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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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