Temporary Shortages of Fluoridation Additives: FAQs
Adjusting the fluoride content of water is a
safe
and healthy practice that provides significant oral health benefits
for a community. For the greatest benefits to occur, it is important to
consistently maintain optimum fluoride levels. The three
fluoride additives used for
water fluoridation are derived principally from phosphate fertilizer
production. Although shortages of fluoride additives for water
fluoridation are infrequent, they do sometimes occur.
Market Outlook
CDC does not track fluoride production or market demand. However, state
water fluoridation programs, utilities, and fluoride suppliers occasionally
share information on market forces with CDC. These unofficial reports and
discussions can reveal trends in the market. The long-range outlook for the
second half of 2008 and first half of 2009 are for an improved supply over
the comparable 2007 period. However, the active hurricane season of 2008
will result in spot shortages of short duration. The fluoride products market is dominated, however, by
only a select few producers and sources, and the supply situation can change
rapidly from what has been observed in recent months.
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How common are shortages or disruptions of
fluoride products?
Shortages or disruptions of fluoride product deliveries are not
common. However, there have been periods of shortages and
disruptions resulting in difficulties obtaining fluoride additives
for water fluoridation. Most shortages and disruptions tend to be of
short duration, on the order of several weeks. Shortages or
disruptions are usually regional. Fluoride products are produced in
only a few areas of the country, and then must be transported to
regional depots, typically by rail tanker car. Therefore, there may
be sufficient fluoride products nationally, but a particular region
may have shortages or disruptions. Shortages or disruptions can also
result from inclement weather in fluoride-producing areas. Florida
is the largest producer of fluoride products, and hurricanes or
other severe weather events can cause phosphate fertilizer
manufacturers to suspend operations for several weeks at a time.
Seasonal disruptions, such as manufacturing plant maintenance
periods, also may delay operations in entire production facilities
for weeks to months at a time. Because the supply of fluoride
products is related to phosphate fertilizer production, fluoride
product production can also fluctuate depending on factors such as
unfavorable foreign exchange rates and export sales of fertilizer.
Other causes of fluoride shortages have been phosphorite rock ore quality with lower fluoride yields, labor disputes involving the
rail or truck transport industry, and other causes.
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Are fluoride shortages or disruptions seasonal in
nature?
Although shortages or disruptions can occur at any time of year,
the most common season for shortages is summer. In the summer
months, irrigation often results in the greatest demand for water,
and water plants can commonly produce 30% to 50% more in summer
months than in winter months. Many water treatment facilities have a
2- to 3-month storage capacity. Planning for summer demand by
storing inventory to the maximum capacity at water treatment
facilities at the beginning of the summer or by scheduling a
delivery in mid-summer can minimize the potential for supply
shortages. Storage of fluoride inventories longer than 6 months
would not be recommended, particularly for dry additives.
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Are shortages or disruptions industry-wide or
supplier specific?
Fluoride additives are produced by several manufacturers, and it is
not common for all the suppliers to be negatively impacted equally when
production problems occur. Consequently, one group of water treatment
facilities may have difficultly obtaining fluoride products from one
supplier while other facilities in the same area may have a sufficient
supply. Water treatment facilities often contract annually with the
lowest bidder for chemicals and supplies. Some larger systems will
negotiate multiple contracts with two or more suppliers, agreeing to
purchase some minimum quantity of fluoride even at a higher cost so that
if shortages or disruptions with one supplier occur, some fluoride can
still be obtained from another source. If you are contracting with a
local supplier of chemical additives, identify the national distributor
furnishing the fluoride for that supplier — it may be possible to
contract with different regional suppliers or different national
distributors.
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Is there a difference between fluorosilicic acid
and dry fluoride product markets?
All of the liquid fluorosilicic acid used for water fluoridation is
produced in North America, so shortages and disruptions of
fluorosilicic acid are limited to U.S. influences. Roughly half of
the dry additive sodium fluorosilicate is domestically produced in
the United States by a single manufacturer and is dependent on the
fluorosilicic acid market or conditions at the single location of
production. The remainder is imported, principally from Asian
sources, and supply is dependent on shipping and transportation
factors. Most sodium fluoride is imported from Asia. Therefore, the availability
of sodium fluoride is more dependent on shipping and transportation
factors. If a surge in demand for dry additives occurs, several
weeks may be required for logistical arrangements to increase
imports and satisfy the greater demand. In spite of these
constraints, historically, there are fewer reports of shortages of
dry additives than of fluorosilicic acid.
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Have there been more shortages in recent years?
There have been more shortages or disruptions in recent years,
although the incidence of shortages and disruptions is expected to
decrease in the coming years. Since the 1980s, the market demand for
national fluoride products has been declining as the historically
greatest users, aluminum manufacturers and glass flux processors, have
either terminated operations or identified alternative fluxes. This has
resulted in a low investment by the industry in new production capacity.
Since the early 2000s, some new uses have emerged for fluorosilicic acid
in computer chip and solar panel production, and this has eliminated the
supply surplus. Manufacturers are responding to this change in market
forces, but investment in new production capacity will be a longer-term
effort. It is expected that the longer-term (1 to 3 years) supply will
return to greater sustainability as manufacturers make new investments
in production equipment.
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Can water treatment facilities minimize their
vulnerability to shortages?
Since the supply of fluoridation products can be subject to
occasional periods of shortages, water treatment facilities should have
at least 3 months of inventory on hand. Water treatment facilities
should monitor their inventories, order supplemental deliveries with
sufficient lead time, and arrange for alternate suppliers who have
different national distributors. It is also beneficial to verify pump
delivery calibration and increase confirmatory testing. Regular and
careful calibration of metering pumps can ensure that optimal
fluoridation is provided with minimal waste.
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Are there strategies for managing inventories if
delivery of fresh product will be delayed?
Calibrate pumping rates and increase monitoring of fluoride additive
feed rates to ensure that excess dosing is minimized. It is important to
maintain feed rates as close to the target within the optimal range for
your community to ensure the benefits of fluoridation — better oral
health and avoidance of tooth decay. However, if inventories are low or
supplies uncertain, it is acceptable to feed fluoride at the lowest
level (0.7 mg/L) recommended for U.S. climates for a short time during
the shortage or disruption. Continued temporary operations at this lower
feed rate will provide some continued protection for your community.
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What should I do if my inventory is exhausted and I
must terminate fluoridation?
Although exhaustion of fluoride products at a water treatment
facility is rare, it does occur. If imminent exhaustion is anticipated,
call your supplier and appeal for a small delivery to satisfy the
immediate need. If fluoridation must be terminated, however, short
periods (1 to 2 months) without fluoridation should not present problems
for a community. Although consistent and constant fluoride levels in the
optimum range provides the greatest benefit to a community, a short
period without fluoride should not result in an immediate increase in
tooth decay. Resumption of fluoridation at the earliest possible date is
important to minimize the potential for tooth decay among residents of
your community.
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Our utility has terminated fluoridation. Who should we
notify?
If a utility must terminate fluoridation, it is important to notify
the state drinking water administrator and
dental director.* Most utilities try
to actively communicate with their customer base about water quality
issues, so notifying public health professionals and the public through
newspaper announcements or press releases may be appropriate if the
utility has used those media outlets in the past. It is important to
give the public a sense of when fluoridation will resume, for example, "We
expect to have delivery of fluoride in 2 weeks and will resume
fluoridation at that time."
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For more information on additives, see the
Water Fluoridation Additives
fact sheet.
* Links to non-Federal organizations are
provided solely as a service to our users. Links do not constitute an
endorsement of any organization by CDC or the Federal Government, and none
should be inferred. The CDC is not responsible for the content of the individual
organization Web pages found at this link.
Page last reviewed: August 2, 2007
Page last modified: August 2, 2007
Content source:
Division of Oral Health, National Center for Chronic Disease Prevention and
Health Promotion |
