New Mexico Dental Journal Winter 2015-2016

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16 New Mexico Dental Journal, Winter 2016
Out of the 5,408 private well fluoride
concentration records from 1950–2014
(United States Geological Survey, the
NMED, and the New Mexico Bureau of
Geology), almost 6% of samples had fluo-
ride levels above 2 mg/L and just over
1 % were over 4 mg/L. Out of all of the
samples tested for fluoride in this dataset,
the average concentration was 0.81
mg/L. Most domestic wells in the state
had fluoride concentrations that did not
exceed the standards set for community
water supplies. Some may actually be too
low in fluoride. However, those wells that
are high in fluoride can have extremely
high fluoride levels, with the highest
concentration of fluoride measured at
20 mg/L in some wells in Taos County.
When Fluoride is too Low
When NMDOH t e st s someone’s
drinking water and the concentration of
fluoride is below 0.7 mg/L, our recom-
mendation is that they inform their
dentist of their water supply source and
the concentration of fluoride. The dentist
may prescribe fluoridated toothpastes or
fluoride treatments.
When Fluoride is too High
When the concentration is right at 2.0
mg/L, and someone asks questions about
their water quality NMDOH asks ques-
tions about their other water sources
including water used for making tea,
coffee and for cooking. If more than half
of their water supply comes from a public
water supply (from school, work or restau-
rants), treated water, or bottled water that
has less than 1.0 mg/L of fluoride, we do
not have any further recommendations.
If the average fluoride concentration in
water that a person is exposed to is higher
than 2.0 mg/L, we recommend that
they take action to lower their exposure
to fluoride. We recommend that they
inform their dentist of the concentra-
tion of fluoride (according to the CDC,
fluoride drops should not be used for
children under the age of 8 if their water
has a concentration above 0.7 mg/L). We
also recommend that they use different
water sources with lower concentrations
of fluoride to reduce their exposure.
Some people choose to install water
treatment to remove excess f luoride
from their water. Other people choose
to haul water from a water supply that
has a lower concentration of fluoride
and others choose to buy bottled water.
Reverse osmosis is an appropriate treat-
ment choice for fluoride, but will not
work well for all domestic wells because
of related concentrations of: iron, manga-
nese, hardness, total dissolved solids; the
pH of the water; and the water pressure
supplied to the home. Each well water/
family situation needs to be evaluated
individually. The well user can work with
a water treatment specialist who installs
water treatment systems. The Environ-
mental Health Epidemiology Bureau
staff are available to answer questions
concerning domestic wells and health
Monday through Friday 8 am to 5 pm
505-827-0006.
References:
Choi AL, Sun G, Zhang Y, Grandjean P.
Developmental fluoride neurotoxicity: a system-
atic review and meta-analysis. Environmental
Health Perspectives. 2013;120:1362–1368. doi:
10.1289/ehp.1104912
Petersen PE. The World Oral Health Report
2003: Continuous improvement of oral health
in the 21st century – the approach of the WHO
Global Oral Health Programme. Community
Dentistry and Oral Epidemiology 2003;32 Suppl
1:3-24.
Sheiham, A., Watt R., 2005 Oral health, general
health and quality of life. Bulletin of the World
Health Organization. 2005:83:9:641–720
.
Fluoride in New Mexico Wells: Health Cost or Benefit?, continued