Preparation and evaluation of candidate certified reference materials (CRMs) for nutrients in seawater
Authors:
- 1 January 2007
- journal article
- research article
- Published by Royal Society of Chemistry (RSC) in Journal of Environmental Monitoring
- Vol. 9 (7) , 708-717
Abstract
Certified reference materials (CRMs) are an essential part of the quality assurance (QA) necessary for the reliable analytical measurement of nutrients in seawater. The CRMs currently available for these analyses are not matrix matched to marine samples. QUASIMEME routinely produces test materials for the nutrients in seawater and nutrients in estuarine water and low-salinity open water Laboratory Performance Studies (LPS) that are both homogeneous and stable. QUASIMEME, in conjunction with Eurofins Scientific, Denmark have produced two reference materials (RMs). The homogeneity testing and preliminary stability studies were carried out by QUASIMEME, and the results are presented in this article. Participants of the QUASIMEME LPS who demonstrated satisfactory long-term performance for the analysis of nutrients in seawater and nutrients in estuarine water and low-salinity open water were invited to take part in the certification exercise. Twenty laboratories returned data, a summary of which is also presented. The certification and long-term stability testing and additional data analysis were carried out by Eurofins Scientific, Denmark, and are outwith the scope of this article and not reported here. Eurofins Scientific, Denmark have marketed these RMs as part of their range of VKI Reference Materials (further information is available from eurofins@eurofins.dk).Keywords
This publication has 10 references indexed in Scilit:
- The International Harmonized Protocol for the proficiency testing of analytical chemistry laboratories (IUPAC Technical Report)Pure and Applied Chemistry, 2006
- A new model for the inference of population characteristics from experimental data using uncertainties. Application to interlaboratory studiesChemometrics and Intelligent Laboratory Systems, 2000
- The QUASIMEME laboratory performance studies (1993–1995): Overview of the nutrients sectionMarine Pollution Bulletin, 1997
- Reference material for nutrients in seawater: stability of nitrate, nitrite, ammonia and phosphate in autoclaved samplesMarine Chemistry, 1995
- The use of buffers to measure the pH of seawaterMarine Chemistry, 1993
- The international harmonized protocol for the proficiency testing of (chemical) analytical laboratories (Technical Report)Pure and Applied Chemistry, 1993
- Autoclaved sea water as a reference material for the determination of nitrate and phosphate in sea waterAnalytica Chimica Acta, 1991
- Robust statistics–how not to reject outliers. Part 2. Inter-laboratory trialsThe Analyst, 1989
- Robust statistics–how not to reject outliers. Part 1. Basic conceptsThe Analyst, 1989
- Reference Materials—What They Are and How They Should be UsedJournal of Testing and Evaluation, 1983