Citric acid doesnt harm.
Chemically it doesnt matter if you get it from GMO or citrus fruits. It's the same.
Ascorbic acid is made similar in industrual scale.
Both are pure cristalized chemical substances. So consider it safe.
Discussion
Thank you for the added context.
A quick search reveals that some people might have an alergic reaction to the synthetic version. Unclear if they also have a reaction to the organic version.