According to AR's research, "Injecting it also has the advantage of avoiding the "first pass" through your liver, and thus places your liver under less stress."
Usually liver toxicity with orals is because of the 'first pass' effect.
Any oral substance or nutrition that is absorbed from intestines first passes through liver (portal circulation) before it enters systemic circulation. That can cause liver toxicity.
Injectables bypass that step and directly enter systemic circulation without first passing through liver.