11266
One - fifth of UO 2 nanoparticles were rapidly cleared from lung ( T ( (1/2) ) = 2 . 4 h ) and translocated to extrathoracic organs .
 Chemical: UO 2
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: UO 2 
Answer:
 Chemical: UO 2