Fluoride Working Group Meeting Book (November 15, 2017)

AOAC Official methods

– AOAC 961.16 (TŝƚƌŝŵĞƚƌLJ) – AOAC 944.08 (Ash- ŝƐƚŝůůĂƚŝŽŶ-Titration) These 2 methods are not suitable for determining low levels of fluoride in infant formula and adult nutritional products. – Microdiffusion and F-ISE ( Microdiffusion and fluoride-specific electrode ĚĞƚĞƌŵŝŶĂƚŝŽŶ ŽĨ ĨůƵŽƌŝĚĞ ŝŶ ŝŶĨĂŶƚ ĨŽŽĚƐ͗ ĐŽůůĂďŽƌĂƚŝǀĞ ƐƚƵĚLJ - ĂďĞŬĂ͕ Z͘ t͕͘ DĐ<ĞŶnjŝĞ͕ ͘ ͘ J͘ K ͕͘ ϲϰ͕ ;ϰͿ͗ 1021-ϭϬϮϲ͕ϭϵϴϭͿ ZĞƐƵůƚƐ ĨƌŽŵ ĐŽůůĂďŽƌĂƚŝǀĞ ƐƚƵĚLJ ǁĞƌĞ ŶŽƚ ĂĐĐĞƉƚĞĚ ďLJ K ͘ DĞƚŚŽĚ ŶŽƚ published.

September 2016

7

German Official Method (Fluo-01) Amtliche Sammlung von hŶƚĞƌƐƵĐŚƵŶŐƐǀĞƌĨĂŚƌĞŶ͕ ŶĂĐŚ WĂƌĂŐƌĂƉŚ ϯϱ >D '.(> ϰϵ͘ϬϬ- ϳͿ͗ ϮƉƉ͕͘ 2000 - ŶĂůLJƐŝƐ ŽĨ ĨŽŽĚƐ͘ ĞƚĞƌŵŝŶĂƚŝŽŶ ŽĨ ĨůƵŽƌŝĚĞ ŝŶ ĚŝĞƚĞƚŝĐ ĨŽŽĚƐ ǁŝƚŚ ĂŶ ion-sensitive electrode. • KŶůLJ validated on 2 dietetic products • Modified and validated with 30 Healthcare products (Nestlé method): – W>KY Zd&͗ уϱϬ ђŐͬϭϬϬŐ ; ŝůƵƚŝŽŶ ĨĂĐƚŽƌ Ϯ with TISAB) – Good Z^ ƌ ;ф ϱйͿ ͬ Z^ ŝZ ;ф ϴйͿ ͬ ZĞĐŽǀĞƌLJ ;ϴϯй-ϭϬϵйͿΎ *Bad ZĞĐŽǀĞƌLJ for products with high protein/thickeners/caseinates due to non specific binding of measured free fluorides Conclusion: method not sensitive & not applicable to products with high protein / thickener/caseinates ĐŽŶƚĞŶƚ н ^>s ;^W/& E ŬŝƚͿ September 2016 8