A community-wide intercomparison exercise for the determination of dissolved iron in seawater

• Published in: Marine Chemistry
• Main Authors: Bowie, A.R., Achterberg, E.P., Croot, P.l., de Baar, H.J.W., Laan, P., Moffett, J.W, Ussher, S., Worsfold, P.J.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2006
• Subjects: Large volume sample; IRONAGES; Intercomparison; Determination; Seawater; Iron; South Atlantic Ocean
• Online Access: https://hdl.handle.net/11370/e13750a0-db36-4a53-a983-94c0c686d55f; https://research.rug.nl/en/publications/e13750a0-db36-4a53-a983-94c0c686d55f; https://doi.org/10.1016/j.marchem.2005.07.002

The first large-scale international intercomparison of analytical methods for the determination of dissolved iron in seawater was carried out between October 2000 and December 2002. The exercise was conducted as a rigorously "blind" comparison of 7 analytical techniques by 24 international laboratories. The comparison was based on a large volume (700 L), filtered surface seawater sample collected from the South Atlantic Ocean (the "IRONAGES" sample), which was acidified, mixed and bottled at sea. Two 1-L sample bottles were sent to each participant. Integrity and blindness were achieved by having the experiment designed and carried out by a small team, and overseen by an independent data manager. Storage, homogeneity and time-series stability experiments conducted over 2.5 years showed that inter-bottle variability of the IRONAGES sample was good (