25 February 2019

Travis Clayton
Email: [FYI request #9627 email]
Copy to: Democracy Services Auckland Council; Ministry of Health

Dear Travis

Request under the Local Government Official Information and Meetings Act 1987 – fluoride
composition

Thank you for your email dated 19 February 2019 that was transferred to Watercare Services
Limited (Watercare) in regards to the composition of fluoride. A response to your queries is
provided below.

As stated previously Watercare obtains Hydrofluorosilicic Acid (HFA) from Ixom New Zealand.
Please find attached the analysis data for the HFA supplied to Watercare by Ixom New Zealand.
This analysis data confirms compliance with the Water New Zealand Good Practice Guide –
Supply of Fluoride for Use in Water Treatment. The HFA supplied to Watercare is approximately
22% fluorosilicic acid and 78% water. The physical properties and trace elements included in this
analysis are selected based on specific maximum acceptable values established in Drinking Water
Standards for New Zealand 2005 (Revised 2018).

Watercare’s ‘Aa’ grading confirms that the water supplied to our customers complies with Drinking
Water Standards for New Zealand and that Watercare manages its water supply systems to a high
standard. Watercare undertakes a comprehensive water quality monitoring programme to
demonstrate compliance with Drinking Water Standards for New Zealand, the results of which are
summarised in our Annual Water Quality reports which are available on our website under Reports
and Publications (https://wslpwstoreprd.blob.core.windows.net/kentico-media-libraries-
prod/watercarepublicweb/media/watercare-media-library/reports-and-
publications/annual_water_quality_report_2017-18.pdf)

Guidance and information regarding the fluoridation of water supplies in New Zealand is provided
by the Ministry of Health. If you wish to seek any further information we respectfully suggest you
contact the Ministry of Health (https://www.health.govt.nz/our-work/preventative-health-
wellness/fluoride-and-oral-health/water-fluoridation)”

Yours faithfully,

Priyan Perera
Head of Operations Excellence
Watercare Services Limited

Document Outline