133 Molesworth Street
PO Box 5013
Wellington 6140
New Zealand
T+64 4 496 2000
30 January 2026
Spencer Jones
By email: [FYI request #33235 email]
Ref:
H2025076959
Tēnā koe Spencer
Response to your request for official information
Thank you for your request under the Official Information Act 1982 (the Act) to the Ministry of
Health – Manatū Hauora (the Ministry) on 11 December for information regarding fluoridation.
The Ministry notes you have reviewed and commented on a recent request received by the
Ministry which sought similar information
: fyi.org.nz/request/32674-fluoride-supply-chain-
information.
In response to this prior OIA published on FYI.org (H2025074650 refers), the Ministry noted it
does not hold information related to several parts of the request and undertook extensive
consultation in order to transfer relevant parts to other government agencies under the Act and
local authorities under the Local Government Of icial Information and Meetings Act 1987
(LGOIMA). This was in order to assist the requester and meet our obligations under the Act to
transfer relevant (parts of) requests where information is not held by the Ministry.
Please note that the Ministry does not hold some of the information requested in your current
request; which appears to have built on the above noted OIA. Some of this information would sit
with other government agencies subject to the OIA, and with local authorities subject to
LGOIMA.
Your request notes “
this request explicitly seeks information held by the Ministry and held on the
Ministry’s behalf” and “
I ask that the Ministry of Health refrain from automatically transferring
questions to councils unless a legal analysis under ss 12, 13, 14 and 18A of the OIA is
provided. Please treat the Ministry as the lead agency for responses unless a transfer is strictly
required.”
As you are aware, from OIA H2025074650, some of the information you’ve requested is not
held by the Ministry. You’ve also requested that the Ministry not automatically transfer your
request to other agencies. Therefore, in order to provide a response as soon as practicable the
Ministry has not explored possible transfer with numerous other government agencies and/or
local authorities.
Each part of your request is addressed in turn. You requested:
“1. End-to-end supply-chain documentation (import → storage → dosing)
Please provide all information (held by MoH or held on MoH’s behalf) regarding the supply
chain for fluoridation chemicals used in New Zealand, including:
1.1 Identity of chemicals and suppliers
a. The exact chemical substances currently used for water fluoridation (e.g.,
hydrofluorosilicic acid (HFA), sodium fluorosilicate, sodium fluoride).
b. Al suppliers, importers, manufacturers, or distributors contracted by councils or their
agents for these chemicals since 2018.
c. Any Ministry documents, contracts, audits, specifications, or product-safety assurances
provided by suppliers to MoH, ESR, Taumata Arowai, or any public authority.
1.2 Chain-of-custody and verification
a. Any documents describing how chain-of-custody for fluoridation chemicals is
maintained from point of import to delivery at treatment plants.
b. Any requirements, standards, or expectations issued by MoH (or Taumata Arowai,
ESR, or predecessor agencies) regarding chain-of-custody, batch testing, or verification of
purity.
The Ministry is not involved with and does not hold information on the supply chain of fluoride/
fluoridation chemicals in New Zealand. Decisions and information held which relates to water
supplies and how fluoridation is administered sits with local authorities. Given each local
authority can choose how this is carried out, it wil vary across New Zealand and over time.
You may wish to refer to the prior OIA response referenced above, which sought similar
information, and the answers provided by the relevant government agencies and local
authorities following the transfer of the relevant part(s) of that request
: fyi.org.nz/request/32674-
fluoride-supply-chain-information.
You may also wish to contact the local authorities directly at:
www.lgnz.co.nz/local-government-
in-nz/councils-in-aotearoa/council-websites-and-maps/.
2. Chemical composition, contaminants, and testing
2.1 Certificates of Analysis (CoAs) and contaminant testing
a. All Certificates of Analysis (CoAs) provided to the Ministry (or to ESR, Taumata Arowai,
or councils but copied to MoH) for fluoride products used in New Zealand since 2018.
b. Any internal reports or assessments regarding contaminants detected in fluoride
chemicals, including but not limited to:
• arsenic, lead, cadmium, mercury
• radionuclides
• polonium
• silica by-products
• industrial manufacturing residues.
2.2 Standards for contaminants
a. Any Ministry-held documents specifying allowable levels of contaminants in fluoridation
chemicals.
b. Any correspondence between MoH and suppliers or councils regarding non-
conformance or marginal results.
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If any contaminants exceed WHO or NZ guideline values, please provide the Ministry’s
risk assessment and decision-making documents.
Water suppliers are responsible for ensuring the purity of the chemicals and the total
concentrations (including impurities) must not exceed the standards set out in the Water
Services (Drinking Water Standards for New Zealand) Regulations 2022. This can be found at:
www.legislation.govt.nz/regulation/public/2022/0168/latest/whole.html.
As noted above, you may wish to refer to the recent request received by the Ministry which
sought similar information, and the answers provided by the relevant government agencies and
local authorities following the transfer of the relevant part(s) of the request:
fyi.org.nz/request/32674-fluoride-supply-chain-information.
3. Regulatory responsibility, oversight failures, and internal knowledge
3.1 Who is responsible?
Please provide documents clarifying which entity (MoH, councils, ESR, Taumata Arowai,
or suppliers) is legally responsible for:
a. verifying chemical purity;
b. approving suppliers;
c. ensuring no harmful contaminants exceed safety thresholds;
d. ensuring chemicals comply with public-health requirements;
e. ensuring that fluoridation substances meet the statutory test of being “safe, effective,
and demonstrably justified” under NZBORA s11 and s5.
If no such documents exist, please confirm this explicitly.
3.2 Internal risk discussions
Please provide any internal Ministry briefings, emails, risk assessments, or advice (2018–
2025) relating to:
a. risks associated with contaminants in fluoridation chemicals;
b. supply-chain vulnerabilities;
c. regulatory oversight gaps;
d. concerns raised by councils or water operators about product quality;
e. the implications of non-oral exposure pathways (inhalation, dermal absorption,
bathing/showering, dialysis).
If no assessments exist on non-oral exposures, please confirm this explicitly.
4. NZ-specific evidence base for safety and medical justification
Please provide any documents (internal or external) that contain New Zealand–specific
evidence relating to:
a. neurotoxicity research (including any reference to NTP evaluations);
b. endocrine, thyroid, renal, or developmental risks;
c. sensitive-population risks (pregnant women, infants, kidney disease, thyroid disorders,
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at-home medical equipment);
d. comparison between actual NZ population exposure versus guideline calculations.
If the Ministry holds no NZ-specific evidence for any category above, please state this
clearly.
5. Post-High-Court judgment work
Following the High Court judgment (New Health / BORA), please provide:
a. Any discussions, legal advice, internal reviews, or policy work about how to ensure
fluoridation decisions remain demonstrably justified.
b. Any analysis regarding how supply-chain transparency impacts the rights-based
justification process.
c. Any risk assessments commissioned or conducted regarding the scientific uncertainty
or contested evidence around neurodevelopment.
These parts of your request are addressed through information that is publicly available on the
Ministry’s website. Please refer to the following webpages:
•
www.health.govt.nz/strategies-initiatives/programmes-and-initiatives/oral-
health/community-water-fluoridation-policy.
•
www.health.govt.nz/strategies-initiatives/programmes-and-initiatives/oral-
health/implementation-of-community-water-fluoridation.
•
www.health.govt.nz/publications/community-water-fluoridation-an-evidence-review .
•
www.health.govt.nz/information-releases/director-general-of-health-consideration-of-
community-water-fluoridation-under-the-new-zealand-bill.
As noted, you may also wish to refer to the OIA response published on FYI.org and a further
OIA response published on the Ministry’s website:
fyi.org.nz/request/32674-fluoride-supply-
chain-information and
www.health.govt.nz/system/files/2024-08/h2024043279_response.pdf.
6. Communications with councils and suppliers (2018–2025)
All communications (emails, memos, letters, briefings) between the Ministry and:
• territorial authorities,
• water operators,
• ESR,
• Taumata Arowai,
• fluoridation chemical suppliers,
relating to:
a. chemical supply issues;
b. purity concerns;
c. import shortages;
d. contaminant warnings;
e. questions about product safety.
The Ministry has identified 3 documents within scope of this part of your request. Al documents
are itemised in Appendix 1 and copies of the documents are enclosed. Where information is
withheld under section 9 of the Act, I have considered the countervailing public interest in
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release in making this decision and consider that it does not outweigh the need to withhold at
this time.
If you wish to discuss any aspect of your request with us, including this decision, please feel
free to contact the OIA Services Team on: [email address].
Under section 28(3) of the Act, you have the right to ask the Ombudsman to review any
decisions made under this request. The Ombudsman may be contacted by email at:
[email address] or by calling 0800 802 602.
Please note that this response, with your personal details removed, may be published on the
Ministry website at:
www.health.govt.nz/about-ministry/information-releases/responses-official-
information-act-requests.
Nāku noa, nā
Jane Chambers
Group Manager, Public Health Policy and Regulation
Public Health Agency | Te Pou Hauora Tūmatanui
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Appendix 1: List of documents for release
# Date
Document details
Decision on release
1
4 November 2022 Letter: Ashburton District
Some information withheld
Council to Director-General of
under section 9(2)(a) of the
Health
Act, to protect the privacy of
natural persons
2
28 November 2022 Letter: Director-General of
Released in full
Health to Ashburton District
Council
3
16 September
Email correspondence: HFA
Some information withheld
2025
supply question
under section 9(2)(a) of the
Act
Please note the Ministry
responded to the query by
telephone.
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