Hi tigerlily,
sodium ascorbate itself is fine, but the colours, flavours, binders, fillers, etc which generally come with supplement tablets are often a problem. I assume you're talking about hemp seed oil. There is a paper which found it to have a trace amount of methyl salicylate, but it's hard to know if this would be a problem, and I haven't found any other information. I've had hemp seed oil without any obvious reaction, but noticed a spicy taste at the bottom of the 2nd bottle I had, and thought it might be a bad sign. You can find quite a lot on fish oil if you do a search of this forum - a lot of people can't tolerate it, but amines seem to be the problem rather than salicylates. I'm not sure about evening primrose oil, but plant oils should generally be treated with caution unless known to be safe.