3939
The present investigations were carried out to study the TiO ( 2 ) NPs - induced apoptosis , oxidative stress and genotoxicity in the human lung cancer cell line , A549 , a widely used cell system for pulmonary toxicity studies .
 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 )