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Suitable substrates include the obvious , such as faecal and hair samples ( e . g . Vigilant et al . 2009 ) , to the less obvious , including environmental DNA extracted from sediments , soil or water samples ( e . g . Taberlet et al . 2012 ) , and as recently demonstrated , the dietary content of blood - sucking invertebrates ( Gariepy et al . 2012 ; Schnell et al . 2012 ) .
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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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