I quoted from Wiktionary, feel free to update the definition there (with sources) if you disagree. Note that the "Synonym: toxic" appears underneath the second

I quoted from Wiktionary, feel free to update the definition there (with sources) if you disagree. Note that the "Synonym: toxic" appears underneath the second (figurative) definition, and in my opinion is perfectly correct; in figurative use poisonous and toxic are used in the same way.