Optimisation of the US EPA (1991) pH-2 extraction method for measuring potentially bioavailable iron (iron III) - 2025

Publication details

This document describes the validation study used to optimise the US EPA (1991) method for the measurement of potentially bioavailable iron using extractions at pH 2 from both freshwater and seawater samples. The recommended method results in reasonable recovery of potentially bioavailable iron from all diluent types tested, particularly if samples are processed within 3 days and a 16-hour extraction period at pH 2 is used. It should be noted that the method provides a measurement of the fraction of iron that may potentially become available to a biological receptor and that in an aquatic environment, some of this iron may ultimately not be available to an aquatic organism.

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ANZG report - the optimisation method for measuring Fe extracted at pH 2 – 2025 (PDF 154 KB)
ANZG report - the optimisation method for measuring Fe extracted at pH 2 – 2025 (DOCX 209 KB)