2423
These results also suggest that environmental exposure to Fe ( 3 ) O ( 4 ) - NPs may play a role in the development of neurodegenerative diseases .
 Chemical: Fe ( 3 ) O ( 4 )
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: Fe ( 3 ) O ( 4 ) 
Answer:
 Chemical: Fe ( 3 ) O ( 4 )