I don't think she's from Nevada. Adding Fluoride to the water in Nevada required a referendum approved by the community, so adding fluoride wasn't common in the 1970's and 1980's. Las Vegas didn't fluoride their water until 2000.
By 1999, only 2.1% of the population of Nevada had fluoride in their water, and the water there does not have much naturally occurring fluoride.
Likely states she is from:
California - Parts of Northern California's Bay Area and Central Valley started fluorinating water in the mid 50's while most of Southern California began to in the 1970's. Southern California also has a high concentration of naturally occurring fluoride. See below.
Colorado, which was one of the first states to start putting fluoride in water. The staining observed on her teeth (dental fluorosis) was historically known as the "Colorado Brown Stain".
Texas - High concentration of natural fluoride, unsure about state laws.
Washington - Data for this was a bit difficult to find but Washington seemed open to fluoridation of their water on a city/town basis in the 1970's/1980's.
Non-western states:
Maryland - had a 100% fluoridation rate in 1982
Connecticut - Mandatory fluoridation laws by 1982
Georgia- Mandatory fluoridation laws by 1982
Illinois- Mandatory fluoridation laws until 1982
Nebraska- Mandatory fluoridation laws by 1982
Minnesota- Mandatory fluoridation laws by 1982
Ohio- Mandatory fluoridation laws by 1982
South Dakota- Mandatory fluoridation laws by 1982
Canada can also be considered
States that can probably be ruled out:
Utah - Like Nevada, there was no statewide addition of fluoride to the water, and adding it required a community referendum. Only had a 2.4% fluoridation rate in their water by 1982.
Oregon - generally historically resistant to fluoridation, only had a 26% fluoridation rate by 2018, not super high concentration on natural fluoride.
Non-western states:
Michigan - weak fluoridation laws by 1982
Kentucky - weak fluoridation laws by 1982
New Hampshire - Community referendum needed
Maine - Community referendum needed
Delaware - Community referendum needed
Most of
Western Europe can be ruled out.
Sources:
Burt, Brian A. “The Epidemiological Basis for Water Fluoridation in the Prevention of Dental Caries.” Journal of Public Health Policy 3, no. 4 (1982): 391–407. https://doi.org/10.2307/3342004.
