Over the counter iron supplements are totally safe to take for the period indicated on them. They contain as much iron as a medium piece of chicken liver.
The medical sites say a safe value is no more than 45 mg per day.
There are also low iron pills (or "gentle iron") that are 28 mg.
So not only are many over the counter pills potentially over the safe levels, but it still doesn't even really answer the question, which is whether the low-dose pills that are under the RDA effective in countering an iron deficiency.
Anyway. I think I'll ask my doctor at a once-every-several-years checkup.