Tomato are closely related to tobacco IIRC (as well as potato). There might be traces of nicotine in the plant, which is a pesticide. This actually also might

Tomato are closely related to tobacco IIRC (as well as potato). There might be traces of nicotine in the plant, which is a pesticide. This actually also might give some fuel as to why people considered it dangerous. EDIT after googling: Yes tomato contains nicotine, in particular before ripening.