Download Community Water Fluoridation Questions and Answers

Community Water Fluoridation
Questions and Answers
Taken from the Ministry of Health (MoH) website on 27 September 2012:
http://www.health.govt.nz/our-work/preventative-health-wellness/fluoridation/fluoridation-questions-and-answers
Is there a difference between fluoride found
naturally in water and fluoride that is added
to water?
It is important to know there is no difference.
The fluoride ions in water are exactly the same
regardless of whether they come naturally from
rocks or are added as calcium fluoride or sodium
silicofluoride. The dental benefits of fluoridated
water occur no matter the source of the fluoride.
Is non-fluoridated water more pure than
fluoridated water?
No. All natural waters contain many different
minerals and compounds, including fluoride. The
amount of each mineral and compound depends on
where the water comes from.
Fluoride occurs naturally in most waters and cannot
be considered an impurity. This was confirmed by
a Privy Council decision in 1963 that stated ‘the
addition of fluoride adds no impurity and the water
remains not only water but pure water and becomes
greatly improved and still natural water containing
no foreign elements’.
How does fluoride help my teeth?
Fluoride works in three ways.
• Fluoride makes teeth more resistant to decay
by strengthening the tooth surface.
• Fluoride interferes with the growth of the
bacteria that cause cavities.
• Fluoride helps to repair the early stages of
tooth decay.
Fluoride can help strengthen baby teeth before they
come through the gums by building fluoride into
their structure. The main effect is when teeth erupt
through the gums. If fluoride is present in saliva,
teeth will continually be exposed to small levels of
fluoride, which helps strengthen the tooth surface.
Fluoridated water is the best way to achieve this.
Do fluoride tablets work as well as
fluoridated water?
No. The benefit of fluoride tablets is limited as they
don’t provide constant small doses throughout the
day and are more expensive over time than water
fluoridation.
The fluoride in the saliva from a tablet lasts only
three hours, and would give less than 1 percent
of the fluoride available from food and drink in a
fluoridated area.
How do we know water fluoridation is
effective?
The effectiveness of water fluoridation has been
documented in scientific literature for well over 50
years. Data from the 1930s and 1940s shows that
even before fluoridation, children drinking naturally
fluoridated water had lower decay rates than
children consuming water without fluoride.
Studies have also shown that when communities
stop fluoridation, there is a reversal of the benefits,
an increase in decay rates and a large increase in the
number of baby teeth extracted.
Most recent studies continue to show that the
difference between fluoridated and non-fluoridated
areas continues to be significant throughout life.
The World Health Organisation has reviewed the
data available and the Public Health Commission
(PHC) in New Zealand published an extensive
review of water fluoridation in 1994 and supports
fluoridation.
In September 2000 the MoH released a report,
written by Environmental Science and Research Ltd
(ESR), evaluating recent evidence of the safety and
effectiveness of water fluoridation.
In 2003 the Public Health Advisory Committee
(PHAC) also reviewed evidence of the effect of water
fluoridation with respect to reducing inequalities in
oral health. It strongly recommended increasing the
proportion of the New Zealand population receiving
fluoridated water.
Does fluoridation cause health problems?
The weight of scientific evidence supporting
the safety and effectiveness of fluoridation is
overwhelming and it is clear the majority of
reputable health, scientific and medical bodies
agree with its use.
Many parts of the world have received naturally
fluoridated water for thousands of years. Large
human populations have now been exposed to
community water fluoridation for many decades and
no persuasive evidence links optimal fluoridation
with any adverse health effects. With hundreds
of millions of people continuing to receive the
benefits of fluoride in drinking-water, the absence
of documented adverse health effects is particularly
convincing.
Can fluoridated water cause toxic effects?
It is impossible to experience fluoride toxicity
from drinking-water optimally fluoridated at levels
between 0.7 ppm to 1 ppm. It would require
drinking more than 5000 glasses of fluoridated water
at one time.
Anything is toxic if you take too much of it, including
many common substances that are essential to
health, for example, water, iron, vitamins A and D
or even oxygen. In excessive quantities fluoride too
can be toxic, but, at the very low concentrations (0.7
ppm to 1 ppm) used in water fluoridation it is not
toxic, even when used over a lifetime.
What if people have health conditions like
kidney disease?
There is no research evidence of increased kidney
disease or dysfunction in humans drinking up to 8
ppm fluoride; nor is there any evidence that existing
kidney disease is made worse.
What if people use a fluoridated toothpaste
as well, will that be too much fluoride?
Studies show that water fluoridation provides
benefits above and beyond those from other
fluoride vehicles alone (for example, toothpaste or
tablets).
Conversely, fluoride toothpastes provide additional
benefits beyond water fluoridation.
Water fluoridation is not a replacement for
toothbrushing with fluoride toothpaste, as brushing
helps to remove the bacteria (found in plaque) and
keeps gums healthy. Rather, the two work hand in
hand to help prevent tooth decay, and provide an
additional benefit above that of fluoridated water
alone.
This requires the ingestion of much larger amounts
of fluoride than anyone in New Zealand would be
exposed to.
What is the benefit of fluoride to teeth when
it is ingested instead of applied topically?
Fluoride ingested and applied topically, such as
drinking-water and brushing teeth with a fluoridated
toothpaste, go hand in hand as effective measures
to help prevent tooth decay.
Sugar intake constantly flowing past teeth needs
good levels of fluoride in plaque and saliva to be
the ‘first line’ in tooth decay prevention.
Human beings are well adapted to living in an
environment with natural fluoride. Some of the
fluoride we ingest is taken up by bones and teeth.
The fluoride taken in to the teeth also helps to
prevent dental decay by strengthening the teeth
and reducing enamel demineralisation. Our kidneys
excrete excessive fluoride from the body, so to
protect teeth over our lifetime it is important to
have small, regular amounts such as is provided in
fluoridated water and fluoridated toothpaste.
When fluoride is ingested regularly when teeth are
developing, it is deposited across the tooth’s entire
surface and this slows down decay. Because of this,
tooth decay in fluoridated areas progresses more
slowly.
What is the difference (in any form of
measurement) between a safe intake and
potentially harmful intake of fluoride?
The Drinking-Water Standards for New Zealand
focus on defining safety standards to prevent
adverse health effects. The recommended
maximum acceptable value (MAV) for fluoride
is proposed as 1.5 mg/l. The guidelines also
recommend the adjustment of water fluoride to
between 0.7 mg/l and 1.0 mg/l for oral health
reasons. Because the dosage is over half the MAV,
this automatically makes the water supply a ‘priority
2’ under the standards. This means the supply must
be monitored to demonstrate compliance with the
standards.
Can a person have too much fluoride in their
body?
Yes, in the same way that a person can have too
many vitamins and other dietary supplements. In
other parts of the world, where there are extremely
high levels of fluoride, it can cause skeletal fluorosis.
For more Ministry of Health questions and
answers visit the Taranaki DHB Website www.tdhb.org.nz
Water Fluoridation Facts
Prepared by the National Fluoridation Information Service (NFIS) www.nfis.org.nz
Key Facts
• Community water fluoridation is the adjustment of natural fluoride levels in drinking water to a
level that will give extra protection against tooth decay. The recommended level of fluoride in New
Zealand community water supplies is 0.7 to 1mg per litre.
• Almost all water sources used in New Zealand to supply drinking water contain low levels of
naturally occurring fluoride from the rock and sediment they flow over.
• Some countries have excessively high naturally occurring levels of fluoride and they use treatment
processes to adjust this down to a safe level.
• Fluoride is added to the water supply by feeder and pump systems and is monitored on at least a
weekly basis by water suppliers who need to meet standards set out in the New Zealand Drinking
Water Standards 2008.
• Currently about 56% of New Zealanders receive fluoridated drinking water supplies.
• Australia also has naturally low levels of fluoride in drinking water sources. Currently more than
80% of Australians have access to drinking water supplies with community water fluoridation
programmes.
• Countries with widespread community water fluoridation schemes include the U.S.A., Canada, the
U.K., Ireland, Spain, Israel, Brazil, Chile, Argentina, Colombia, Hong Kong, South Korea, Singapore
and Malaysia.
• Many European countries and some Central and Southern American countries with naturally low
levels of fluoride in water sources, use fluoridated salt widely. Milk fluoridation schemes also exist
in several countries. In some countries community water fluoridation is not practical due to the
complex and very old water systems without a single point to add fluoride.
• The Centre for Disease Control and Prevention rate community water fluoridation as one of the top
ten public health achievements in the 20th century. The World Health Organisation (WHO) restated
its support for community water fluoridation in 2007, in its Global Policy for improvement of oral
health.
Benefits
• The optimal level of fluoride in New Zealand community water supplies is 0.7 – 1mg per litre. This is
the lowest amount at which the benefits to dental health can be achieved, while minimising any risk
of dental fluorosis.
• Because of its role in dental health, fluoride is considered a nutrient by the National Health and
Medical Research Council and the New Zealand Ministry of Health.
• The 2009 New Zealand Oral Health Survey showed that overall children and adults living in
fluoridated areas had significantly lower lifetime experience of dental decay than those in nonfluoridated areas.
• The risk of dental decay is highest for lower socio-economic groups, who can least afford dental
care. It is also these groups that benefit most from decay prevention due to community water
fluoridation.
• Most New Zealand studies since 1980 have continued to show benefits of water fluoridation. A 1994
review found 2 studies showed no benefit. The remaining 13 studies showed benefits ranging from
14% to 36% reductions in tooth decay for older children and from 12% to 56% reductions in affected
tooth surfaces for younger children.
• The National Health and Medical Research Council of Australia commissioned a review in 2007
to evaluate scientific data on fluoridation. The review affirmed that community water fluoridation
remains the most effective and socially equitable means of achieving the dental decay preventative
affects of fluoride.
Safety
• Many substances we use every day are beneficial in small amounts, but may be harmful in large
amounts – for example salt and water.
• Adding fluoride to the water to prevent dental decay can be compared to other nutritional
measures such as adding Vitamin D to margarine to maintain healthy bones, folic acid to breakfast
cereals to reduce the risk of babies being born with neural tube defects and iodine to salt for
thyroid health. Other preventative public health measures include smoking restrictions, compulsory
seat belts, and immunisation.
• Almost all water sources and additives to treat drinking water contain small levels of chemicals
which is why they are monitored routinely to meet the New Zealand Drinking Water Standards 2008.
• From birth to the age of about seven years when teeth are forming excessive fluoride intake may
result in altered formation of the tooth enamel, called dental fluorosis. This looks like white specks
in the tooth enamel while more serious forms look like brown stains or pitting. In New Zealand there
is a low prevalence of mild and moderate fluorosis and no reported evidence of the more severe
forms of fluorosis.
• There is no established link between water fluoridation and the risk of bone cancer (osteosarcoma).
Published reviews have also stated that there is no consistent evidence of an association between
community water fluoridation and ill-health or death due to cancer in general.
• There is no current credible evidence of a link between community water fluoridation and thyroid
disease.
• There is no evidence linking reduced Intelligence Quotient (IQ) scores with community water
fluoridation. There have been studies linking low IQ with naturally high fluoride in water supplies
although they are problematic due to a number of influences on the study samples.
• No evidence exists that community water fluoridation poses any health risk for people with chronic
kidney disease, although only limited relevant studies are available.
Extracts from February and July 2012 issues of the NFIS Newsletter. These can be found on the NFIS website.
2009 New Zealand Oral Health Survey
What’s happening elsewhere?
• 4906 New Zealanders participated in the New
Zealand Oral Health Survey, including 1961
Maori, 622 Pacific and 755 Asian respondents.
• The survey showed large improvements in oral
health have occurred for children, with the
proportion of 12-13 year olds surveyed who were
decay-free almost doubling since the last oral
health survey in 1988.
• Adolescents aged 12-17 years had worse oral
health than the younger age groups surveyed.
• Children and adults living in areas with
community water fluoridation had significantly
lower lifetime experience of dental decay than
those living in nonfluoridated areas.
• The majority of adults (18 and over) surveyed
had some natural teeth, with 88.6% having 21 or
more natural teeth.
• Two in three (65%) adults surveyed brushed their
teeth with fluoride toothpaste at least twice a
day.
• Only 43% of 2-17 year olds brushed their teeth
twice daily with fluoride toothpaste.
• The survey found no significant difference in the
prevalence of fluorosis between people living in
fluoridated and nonfluoridated areas.
• In 2011 approximately 56% of New Zealanders
were receiving fluoridated drinking water.
• Whakatane District Council, and Hastings
District council are holding referendums about
whether to continue with their community water
fluoridation programmes during their 2013 local
body elections.
• Lower Hutt City Council and Dunedin City
Council have decided to continue with
community water fluoridation.
• Waikato District Council is considering
expanding their community water fluoridation
programme.
• Clutha District Council commenced community
water fluoridation in Tapanui and Milton in late
2010, and in Kaitangata in February 2011.
• The Ranfurly Community Board in the Central
Otago District Council agreed to commence
water fluoridation and are expected to have
fluoride added to their water supplies in late
2012 after the instalment of the necessary
equipment and monitoring systems.
Where can I go for more
information?
Taranaki District Health Board
You can find further information on Community Water Fluoridation on the TDHB website:
http://www.tdhb.org.nz/services/public_health/fluoride.shtml
If you want to talk to someone about water fluoridation contact your Dentist or phone 08000 TALK TEETH
(0800 825 583).
National Fluoride Information Service
The National Fluoride Information Service (NFIS) is an association funded by the Ministry of Health
(MoH). Led by Regional Public Health, it also includes the Hutt Valley DHB Community Dental Services,
Environmental Science and Research, Centre for Public Health Research at Massey University and the
National Poisons Centre.
There is ongoing research and monitoring around the world looking at the effectiveness and safety of water
fluoridation programmes. NFIS has been established to monitor and assess this work and to provide advice
on these issues. NFIS offers robust and independent scientific and technical information around water
fluoridation to District Health Boards (DHBs) and Territorial Local Authorities (TLAs).
Website:
http://www.rph.org.nz/content/14350004-1cf6-45ad-a32d-d35311bfe2fc.html
Ministry of Health
The Ministry of Health leads New Zealand’s health and disability system, and has overall responsibility for
the management and development of that system.
Website:
http://www.health.govt.nz/our-work/preventative-health-wellness/fluoridation
New Zealand Dental Association
The New Zealand Dental Association (NZDA) is the professional association for New Zealand dentists.
NZDA is the one body able to speak on behalf of NZ dentistry as a whole. They also provide information
and advice to consumers. Healthy Smiles is the New Zealand Dental Association website for the public,
students, teachers, health professionals and the media.
Follow this link:
http://www.healthysmiles.org.nz/default,224,statements-and-recommendations.sm
Victoria Government Health Information - Fluoridation
The Department of Health, Victoria, Australia, Victorian Government Health Information website is a
gateway to information on community water fluoridation.
Follow this link:
http://www.health.vic.gov.au/environment/fluoridation/
World Health Organisation
Visit their website: http://www.who.int/en/