18293
The selectivity of debromination was studied , and the major octa - BDE products photochemically debrominated from nona - BDEs were identified .
 octa - BDE, nona - BDEs
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 octa - BDE, nona - BDEs