10937
Although there are reports that oxidative injury may play a role in the pathophysiology of some neurologic disorders , such as migraine and epilepsy , by disrupting or destroying cell membranes through the formation of free radical and reactive oxygen species , the pathophysiology of headache is not clearly established .
 Chemical: oxygen
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: oxygen