First international comparative study of volatile fatty acids in aqueous samples by chromatographic techniques: Evaluating sources of error

Abstract This first international proficiency-testing scheme evaluated the analytical performance and the state of practice in measurement of volatile fatty acids in aqueous samples. Gas chromatography and high-performance liquid chromatography were used by 25 laboratories from 15 different countries. Two reference materials were selected for analysis. The performance of each laboratory was assessed by the internationally-accepted z-score. The overall performance was rather poor. Among the causes of poor analytical performance, human errors and inadequate calibration were probably the major problems encountered.

[1]  D. T. Hill,et al.  Using volatile fatty acid relationships to predict anaerobic digester failure. , 1987 .

[2]  Michael Thompson,et al.  The International Harmonized Protocol for the proficiency testing of analytical chemistry laboratories (IUPAC Technical Report) , 2006 .

[3]  N. Yaylı,et al.  A proficiency test scheme for the quality control of black tea and development of quality control material for internal quality control , 2011 .

[4]  Lars Jorhem.  Promoting analytical quality control of trace-element data to be presented in international journals and reports , 2008 .

[5]  Stephen L. R. Ellison,et al.  Erratum to: Causes of error in analytical chemistry: results of a web-based survey of proficiency testing participants , 2012, Accreditation and Quality Assurance.

[6]  R. Nordstedt,et al.  Wood Block Media for Anaerobic Fixed Bed Reactors , 1985 .

[7]  B. Bulletin.  Analyzing Fatty Acids by Packed Column Gas Chromatography , 1999 .

[8]  A. T. James,et al.  Gas-liquid partition chromatography: the separation and micro-estimation of volatile fatty acids from formic acid to dodecanoic acid , 1952 .

[9]  Philip J Lowthian,et al.  Effectiveness of analytical quality control is related to the subsequent performance of laboratories in proficiency tests , 1993 .

[10]  M. Ricci,et al.  Challenges in preparing water-matrix reference materials for PAHs and pesticides: examples from SWIFT-WFD proficiency-testing schemes , 2009 .

[11]  D. MacDougall,et al.  Guidelines for data acquisition and data quality evaluation in environmental chemistry , 1980 .

[12]  P. Szecsi,et al.  Error tracking in a clinical biochemistry laboratory , 2009, Clinical chemistry and laboratory medicine.

[13]  Michael Koch.  Regulatory aspects of proficiency testing: experience from the water sector , 2004 .

[14]  Ana Sayago,et al.  The correlation coefficient attacks again , 2006 .

[15]  D. T. Hill,et al.  Digester stress as related to iso-butyric and iso-valeric acids , 1989 .

[16]  Tadeusz Ossowski,et al.  Determination of Volatile Fatty Acids in Environmental Aqueous Samples , 2008 .

[17]  T. R. Wood,et al.  Determination of Chlorogenic Acid in Coffee , 1948 .

[18]  Nick Boley,et al.  Comparability of PT schemes – what did we learn from COEPT? , 2006 .

[19]  The SWIFT-WFD Proficiency Testing campaigns in support of implementing the EU Water Framework Directive , 2007 .

[20]  Rob G. Visser.  Interpretation of interlaboratory comparison results to evaluate laboratory proficiency , 2006 .

[21]  T. E. Larson,et al.  Chromatographic determination of volatile acids , 1956 .

[22]  M. J. Gardner.  Quality control techniques for chemical analysis: some current shortcomings and possible future developments , 2007 .

[23]  R. Dinsdale,et al.  Development of a static headspace gas chromatographic procedure for the routine analysis of volatile fatty acids in wastewaters. , 2002, Journal of chromatography. A.

[24]  E. Emery,et al.  Gas Chromatographic Determination of Trace Amounts of the Lower Fatty Acids in Water , 1961 .

[25]  Mike Gardner,et al.  How well should laboratories perform in proficiency tests. , 2004, Journal of environmental monitoring : JEM.

[26]  R. J. Blake,et al.  Possible Errors in the Analysis of Lactic Acid and Volatile Fatty Acids in the Gastrointestinal Tracts of Pigs and Chickens , 2005, Applied and Environmental Microbiology.

[27]  A. G. Asuero,et al.  The Correlation Coefficient: An Overview , 2006 .

[28]  José Miguel Silván,et al.  Comparison of different statistical methods for evaluation of proficiency test data , 2008 .

[29]  K. Buchauer,et al.  A comparison of two simple titration procedures to determine volatile fatty acids in influents to waste-water and sludge treatment processes , 1998 .

[30]  N. Narkis,et al.  Direct analytical procedure for determination of volatile organic acids in raw municipal wastewater , 1978 .

[31]  Johanna Smeyers-Verbeke,et al.  Inter-laboratory studies in analytical chemistry , 2000 .

[32]  Ilya Kuselman,et al.  Human errors and reliability of test results in analytical chemistry , 2013, Accreditation and Quality Assurance.

[33]  M. Buchgraber,et al.  Interlaboratory evaluation of injection techniques for triglyceride analysis of cocoa butter by capillary gas chromatography. , 2004, Journal of chromatography. A.

[34]  S. A. Fleck,et al.  Gas-Liquid Partition Chromatography , 1955 .

[35]  D. T. Hill,et al.  Long chain volatile fatty acid relationships in anaerobic digestion of swine waste , 1988 .

[36]  W. I. Patterson,et al.  Separation and Determination of the Straight-Chain Saturated Fatty Acids C5 to C10 by Partition Chromatography , 1948 .

[37]  A. E. Greenberg,et al.  Standard methods for the examination of water and wastewater : supplement to the sixteenth edition , 1988 .

[38]  R W Jenny,et al.  Causes of unsatisfactory performance in proficiency testing. , 2000, Clinical chemistry.

[39]  Yiu-chung Yip,et al.  Assessing laboratory performance in intercomparisons for inorganic analysis , 2009 .

[40]  Bernard King,et al.  Achieving traceability in chemical measurement—a metrological approach to proficiency testing , 2003 .

[41]  Pedro Araujo,et al.  Key aspects of analytical method validation and linearity evaluation. , 2009, Journal of chromatography. B, Analytical technologies in the biomedical and life sciences.