As a lot of fish are polluted with mercury, my guess is that getting omega 3 can be the same "problem" for mercury toxic people who want to avoid fish as vegetarians.

I was reading an article online the other day that was mentioning the need to have omega 3 because we are inundated by omega 6 from various sources. It was saying that too much omega 6 and not enough omega 3 can cause problems, including infertility - which was particularly interesting for me having PCOS (supposedly)

Anyway, one non-fish source that I have started taking is pure flax seed oil. I think I read that someone here was getting bad reaction to the flax seed, but can't remember the details?

Any one know of any other non-fish/animal sources of omega 3?