15278
After 2h exposure at higher test concentrations ( 10 - 50 mu g / l ) , oxidative stress was apparent , as reflected by significantly higher levels of protein and lipid oxidation and significantly greater superoxide dismutase activity .
 Chemical: superoxide
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: superoxide