1481
On the contrary , with photoactivation , the toxicity of TiO ( 2 ) nanoparticles significantly increased , which correlated well with the specific surface area of the particles .
 Chemical: TiO ( 2 )
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: TiO ( 2 )