34 points
It doesn’t. This is high-school chemistry.
Fluoride only “accumulates” up to the peak concentration of the environment (no further) on places where it is removed from contact with that environment.
You can only accumulate fluoride in the soil if you keep adding it and there is almost no rain to wash it away.
-10 points
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Like how crops are irrigated with town water, and in many areas with lowering rainfall? Accumulates in fruit, vegetables, leaves too
17 points