Frozen Ahi Poke'from Vietnam

[kimo wires]

Hey All, I've been buying the Fresh Frozen Ahi from the local grocery in Hilo. Not going to say the name but everyone knows the one at Puainako. I've read that the Vietnamese Tuna  is treated with Carbon Monoxide and may have been handled improperly. 
I've never gotten sick tho. It's half the price of fresh local Ahi.  I was wondering if anyone else was buying it? Thoughts? 
Thanks in advance for replies. Aloha KW