Participation In Proficiency Testing Schemes Research Articles

The multifaceted impact of ISO/IEC 17025 accreditation: a sector-specific analysis in civil engineering testing and calibration laboratories

PurposeThis study aims to dissect the multifaceted impact of ISO/IEC 17025 accreditation, specifically within civil engineering testing and calibration laboratories. To achieve this, it intends to explore several key objectives: identifying the prominent benefits of accreditation to laboratory performance, understanding the advantages conferred through participation in proficiency testing schemes, assessing the role of accreditation in enhancing laboratory competitiveness, examining the primary challenges encountered during the accreditation process, investigating any discernible adverse effects of accreditation on laboratory performance and evaluating whether the financial cost of accreditation justifies the resultant profitability.Design/methodology/approachThis study employs a qualitative approach through semi-structured interviews with 23 industry professionals—including technical managers, quality managers, external auditors and clients. Thematic analysis, guided by Braun and Clarke’s six-stage paradigm, was utilized to interpret the data, ensuring a comprehensive understanding of the accreditation’s impact.FindingsFindings reveal that accreditation significantly enhances operational processes, fosters quality awareness and facilitates continuous improvement, contributing to greater client satisfaction. In addition, standardized operations and rigorous quality controls further result in enhanced performance metrics, such as staff capability and measurement accuracy. However, the study also uncovers the challenges of accreditation, including high resource costs and bureaucratic hurdles that can inhibit innovation and slow routine operations. Importantly, the research underscores that the impact of accreditation on profitability is not universal, but contingent upon various factors like sector-specific regulations and market demand. The study also highlights sector-specific variations in the role of accreditation as a marketing tool and differing perceptions of its value among clients. It further emphasizes the psychological stress of high-stakes evaluations during audits.Originality/valueThis study represents the first in-depth investigation into the impact of ISO/IEC 17025 accreditation on civil engineering testing and calibration laboratories, directly contributing to the enhancement of their quality and operational standards. Providing actionable insights for laboratories, it underscores the importance of weighing accreditation costs and benefits and the necessity for a tailored approach to the unique market and regulatory landscapes they operate in.

Matrix Effect Evaluation in GC/MS-MS Analysis of Multiple Pesticide Residues in Selected Food Matrices

Multi-analyte methods based on QuEChERS sample preparation and chromatography/mass spectrometry determination are indispensable in monitoring pesticide residues in the feed and food chain. QuEChERS method, even though perceived as convenient and generic, can contribute to sample matrix constituents’ introduction to the measuring system and possibly affect analytical results. In this study, matrix effects (ME) were investigated in four food matrices of plant origin (apples, grapes, spelt kernels, and sunflower seeds) during GC-MS/MS analysis of >200 pesticide residues using QuEChERS sample preparation. Data analysis revealed considerable analyte signal enhancement and suppression: strong enhancement was observed for the majority of analytes in two matrices within the commodity groups with high water content—apples, and high acid and water content—grapes (73.9% MES and 72.5% MEA, and 77.7% MES and 74.9% MEA, respectively), while strong suppression was observed for matrices within the commodity groups with high starch/protein content and low water and fat content—spelt kernels, and high oil content and very low water content—sunflower seeds (82.1% MES and 82.6% MEA, and 65.2% MES and 70.0% MEA, respectively). Although strong matrix effects were the most common for all investigated matrices, the use of matrix-matched calibration for each sample type enabled satisfactory method performance, i.e., recoveries for the majority of analytes (up to roughly 90%, depending on the fortification level and matrix type), which was also externally confirmed through participation in proficiency testing schemes for relevant food commodity groups with the achieved z-scores within acceptable range ≤ |2|.

Development and Validation of an UHPLC-MS/MS Method for the Simultaneous Determination of 11 EU-Regulated Mycotoxins in Selected Cereals.

The availability of reliable sensitive multi-analyte methods for unambiguous determination of mycotoxins is crucial for ensuring food and feed safety, considering their adverse health effects and (co-)occurrence in various foods. Accordingly, a multi-mycotoxin confirmatory method for simultaneous determination of 11 mycotoxins regulated in cereals within the European Union (EU) using ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) was developed and in-house validated to fit the EU legislation requirements for analytical methods. A simple sample preparation was based on a solid–liquid extraction using a solvent mixture acetonitrile/water/formic acid (79/20/1, v/v/v) and a dilution of raw extract using water/acetonitrile/formic acid (79/20/1, v/v/v) before instrumental analysis. Average recoveries in all three validated cereal crop types (maize, wheat, and barley), spiked at multiple levels, were found acceptable for all analytes when matrix-matched calibration was used, ranging from 63.2% to 111.2% and also showing very good repeatability, with relative standard deviations below 20%. Matrix effect (SSE) evaluation revealed maize as the most complex of the three analyzed cereal matrices, with strong SSE (<50% and >150%) recorded for all 11 analyzed mycotoxins. An additional method verification was performed through successful participation in proficiency testing schemes, with the achieved z-scores generally in the acceptable range of −2 ≤ z ≤ 2. The obtained validation results demonstrated the suitability of the developed confirmatory multi-mycotoxin UHPLC-MS/MS method based on a dilute-and-shoot principle for the simultaneous determination of low concentrations of 11 EU-regulated mycotoxins in cereals, including aflatoxins B1, B2, G1 and G2, deoxynivalenol, fumonisins B1 and B2, zearalenone, T-2 and HT-2 toxins, and ochratoxin A.

Continual Improvement of the Reliability of Next-Generation Sequencing-Based ctDNA Analysis: A Long-Term Comparison of ctDNA Detection in China.

Since circulating tumor DNA (ctDNA) sequencing is increasingly being applied in clinical management of patients with cancer, its testing accuracy has become a matter of serious concern. To address this issue, a long-term ctDNA analysis proficiency testing (PT) scheme for next-generation sequencing (NGS) was launched in China in 2018, serving as an educational tool for assessing and improving the testing quality of NGS-based ctDNA detection. Feedback from participating laboratories across 23 different PT samples containing different variants with varying variant allele frequency was collected between 2018 and 2021. To further show the landscape of changing conditions in accuracy and reliability of NGS-based ctDNA testing, performance was analyzed by evaluating the cfDNA extraction kits, testing panels, target enrichment strategies, and sequencing platforms. During the 4 years, 2745 results reported from 504 laboratories were evaluated. Only 66.3% of results from laboratories were entirely in concordance with the expected results. Nonetheless, along with an increasing number of participating laboratories, the number of errors occurring in laboratories, and the proportion of laboratories that experienced errors both showed a significant downward trend. No obvious differences in the error rates were found regarding the kit manufacturers or sequencing platform. Moreover, the individual performances of the laboratories improved when they participated in more PT scheme rounds. These data demonstrated that the performance of individual Chinese laboratories for NGS-based ctDNA analysis continuously improved over time with participation in PT schemes. However, further care must also be taken in standardized operations and validations.

Features of the Functioning of the National Metrological System in the Health Sector

The legislative requirements for metrological support in the healthcare sector, the issues of ensuring metrological traceability and the hierarchical scheme of calibrations and measurements in laboratory medicine according to the recommendations of JCTLM and their adaptation at the national level are considered. The features of the provided metrological control of measuring instruments for medical purposes, including when conducting their compliance assessment with the requirements of technical regulations. The current state of affairs in the confirmation of the technical competence of medical laboratories, including the need for their participation in proficiency testing schemes through inter-laboratory comparisons, in the transition from certification to accreditation is considered.&#x0D; The analysis of the used methods and means of calibration and reference measurements proposed by JCTLM and other leading orga­nizations in the field of laboratory medicine is observed. Information is provided on the work carried out by the SE «Ukrmetrteststandart» for metrological support of medical measuring instruments. The necessity of legal improvement, the regulatory and methodological base of the metrological system in the field of healthcare is substantiated. As a result of the work performed, the authors consider:&#x0D; &#x0D; the legislative base of metrological support in the field of healthcare is not perfect and in need of refinement of the profile of the central executive authorities in order to build technically sound organizational and regulatory frameworks for metrological support in this area;&#x0D; proficiency testing through interlaboratory comparisons in the field of laboratory medicine is an effective tool for confirming the technical competence of the laboratory. Laboratories should parti­cipate in proficiency testing schemes on a regular basis. Proficiency testing providers should pay particular attention to the method of determining reference values of indicators in proficiency testing samples, using predominantly metrologically sound procedures based on the use of standards, certified reference materials and/or reference measurement methods;&#x0D; the heads of medical laboratories should be careful about the choice of suppliers of legal acts in the metrology.&#x0D;

Changes to proficiency testing in developing countries over the last 10 years

Participation in proficiency testing schemes is necessary and beneficial for all testing laboratories across the world. Laboratories in developing countries face particular challenges in this context. These have been discussed during the last 10 years at various international workshops organized by Eurachem. An online survey on the developments during this period has been performed, and the results are presented here. Affordability and availability of proficiency tests as well as transport and customs issues are still the major problems. Installation of national or regional schemes could solve some of these problems, but their sustainability is a challenge. Finally, the author’s personal opinion on the conclusions that can be drawn from the results of the survey is given.

Overview of proficiency testing provision in pharmaceutical area in Brazil and an educational scheme for determining mefenamic acid in raw materials

An historical review indicated that the provision of proficiency testing (PT) in the pharmaceutical area in Brazil is critical. Three providers were identified in the period between 2002 and 2015; only one provider was regular, but none was accredited according to the requirements of ISO 17043. A PT was organized without registration fees for educational purposes for the determination of mefenamic acid (2-[(2,3-dimethylphenyl)amino]benzoic acid) in raw materials. Proficiency test items consisted of a mixture of mefenamic acid and polyvinylpyrrolidone in the mass ratio 90:10. This proportion was used to simulate an adulterated raw material. Homogeneity and stability testing was performed and indicated that the materials were suitable for use in the PT scheme. First, 68 pharmaceutical laboratories, of which five were ISO 17025 accredited, were contacted to disseminate information about the specific PT and the benefits of this important quality assurance tool. Then, the proficiency test items were sent to the 13 registered participants, of which two were ISO 17025 accredited. In addition, the participating laboratories were surveyed regarding the technical and management aspects of their quality management system (QMS), such as the status of the accreditation process according to the ISO 17025 requirements, staff training, equipment calibration and participation in other PT schemes. All 11 participants that reported results in the study adopted the United States Pharmacopoeia Official Method. Only one laboratory, representing 9.1 % of the participants, had an unsatisfactory z-score result. Factors such as the reduced number of ISO 17025 accredited laboratories, the low number of participants in the educational PT, the high proportion of laboratories that participated for the first time and the portion of the participants who did not know about PT and its importance were considered as determinants for the restricted availability of the PT supply for medicines, as evidenced in the present study in Brazil. Thus, an urgent need for nationwide actions was identified to promote the critical consciousness of managers regarding QMS in pharmaceutical laboratories, including the importance of participation in PT schemes, as well as the importance of encouraging the providers already structured to broaden their scope in this area.

Single-Laboratory Validation of a Multitoxin Ultra-Performance LC-Hydrophilic Interaction LC-MS/MS Method for Quantitation of Paralytic Shellfish Toxins in Bivalve Shellfish.

A single-laboratory validation study was conducted for the hydrophilic interaction-LC-MS/MS analysis of paralytic shellfish toxins (PSTs) in bivalve shellfish. The method was developed as an alternative to the precolumn oxidation AOAC 2005.06 and postcolumn oxidation AOAC 2011.02 LC with fluorescence detection methods, receptor binding assay AOAC 2011.27, as well as the mouse bioassay AOAC 959.08. PSTs assessed were saxitoxin, neosaxitoxin, deoxydecarbamoylsaxitoxin, decarbamoylsaxitoxin, decarbamoylneosaxitoxin, gonyautoxins 1-6, decarbamoylgonyautoxins 2-3, and N-sulfocarbamoyl gonyautoxins 2&3. The method also included the determination of decarbamoylgonyautoxins 1&4, N-sulfocarbamoyl gonyautoxins 1&4, and M toxins. Twelve commercially produced bivalve species from both New Zealand and the United Kingdom were assessed, including mussels, oysters, scallops, and clams. Validation studies demonstrated acceptable method performance characteristics for specificity, linearity, recovery, repeatability, and within-laboratory reproducibility. LOD and LOQ were significantly improved in comparison to current fluorescence-based detection methods, and the method was shown to be rugged. The method performed well in comparison to AOAC 2005.06, with evidence obtained from both comparative analysis of 1141 PST-contaminated samples and successful participation in proficiency testing schemes. The method is suitable for use in regulatory testing and will be submitted for an AOAC collaborative study.

Diagnosis of Vibrio cholerae O1 Infection in Africa

Isolation of Vibrio cholerae O1 is necessary for cholera outbreak confirmation. Rapid diagnostic testing of fecal specimens, based on lipopolysaccharide detection of V. cholerae O1 or O139, may assist in early outbreak detection and surveillance. Cary-Blair transport medium is recommended for specimen transport. Filter paper, although used in epidemics, needs evaluation against rectal swab specimens. Fecal specimens are subcultured onto selective and nonselective media, including 5% blood agar and TCBS agar, for detection of V. cholerae O1 or O139. Suspicious, oxidase-positive isolates are serotyped in monovalent antisera. Antimicrobial-susceptibility testing is performed to detect resistance. Molecular characterization supports phenotypic identification and outbreak investigations. The presence of genes encoding cholera toxin, lipopolysaccharide, and El Tor biotype traits can be confirmed. Standardized pulsed-field gel electrophoresis analysis facilitates strain comparison. Quality management ensures reliability of results through validation and verification of functional laboratory equipment; quality control of testing procedures, laboratory reagents, and consumables; and participation in proficiency-testing schemes.

Data quality in water analysis: validation of combustion-infrared and combustion-chemiluminescence methods for the simultaneous determination of Total Organic Carbon (TOC) and Total Nitrogen (TN)

Total Organic Carbon (TOC) and Total Nitrogen (TN) were simultaneously determined in water samples, applying the high-temperature (720°C) catalytic combustion (Pt/Al2O3) oxidation method. The detection of TOC and TN was performed using an infrared or a chemiluminescence detector, respectively. Following current law legislations as well as the need to provide accurate and repeatable results, a systematic work has been successfully undertaken for the accreditation according to EN ISO 17025/99. Method characteristics (r ange of measurement, calibration, method detection level, repeatability, reproducibility, precision, accuracy) and measurement uncertainties were determined, while participation in proficiency testing schemes was also implemented. The above methods were tested for the study of water purification from organic pollutants. To this end, organic dyes have been used as model organic pollutants and anionic hydrogels have been used as sorbents. With respect to the colorimetric techniques, TOC-TN characterization is proved to be a reliable tool with significantly lower detection limits of the organic load.

Data quality in water analysis: validation of ion chromatographic method for the determination of routine ions in potable water

Ion chromatography provides a simple, fast, small sample volume demanding, and fit-for-purpose methodology for the concurrent determination of 10 ions (F −, Cl −, Br −, NO 3 −, PO 4 3−, SO 4 2−, Na +, K +, Ca 2+ and Mg 2+) in surface, ground and potable water samples. Current law legislations, as well as the need to constantly provide accurate and reliable results, enforce public sector laboratories to practice quality management system, according to the EN ISO 17025 standard. In this paper, the work that was undertaken for the accreditation of the above determinations at the chemical laboratory of EYDAP SA, is presented. The laboratory has developed two in-house methods, which are carried out simultaneously by a dual chromatographic system. The method for the analysis of anions is based on the 4110B APHA standard method and the one for the cations based on the ISO14911. Deviations from the standard procedure made a full method validation imperative, therefore, for all 10 ions, method characteristics were determined and assessed towards the fitness-for-purpose scope (range of measurement, calibration, method detection level, level of quantification, repeatability, reproducibility, precision, accuracy, peak resolution). Additionally, measurement uncertainty was determined and procedures for daily measurement quality control, assessment of individual analyst capability, measurement, sample and reagent traceability, and regular participation in proficiency testing schemes were implemented. Methodology and results for method validation, uncertainty quantification and quality control is presented in detail in the full paper.

Policies, requirements and surveys concerning frequency for participation in proficiency testing schemes

This paper focuses on policies and requirements concerning the frequency for participation in proficiency testing (PT) and provides an overview of the frequency for which PT activities are offered in 25 testing fields. Recent international surveys are summarised.

EPTIS: The new European database of proficiency testing schemes for analytical laboratories

Quality represents a cornerstone in the credibility of analytical laboratories. Their performance must be systematically checked through participation in proficiency testing schemes, co-ordinated by independent providers. These establish the organisational arrangements and the interpretation of results for evaluating the technical competence of the laboratories. The EPTIS database (European Proficiency Testing Information System) aims to establish an important link between all potentially participating laboratories and proficiency testing scheme organisers, as well as the systematisation of all relevant European information. This article describes the promotion of this new database and how the proficiency testing schemes operate in Portugal.

The proof of analytical chemical education lies in proficiency testing: a proficiency testing programme in polytechnic academia and vocational colleges in The Netherlands.

Participation in proficiency testing schemes (PT-schemes) is an important way to prove and to improve the skills of analytical chemical students. It gives valuable information on the professional capabilities of the students and is thus an important step in the training of laboratory engineers and technicians. In the programme described three types of samples are offered to the students: chemical, environmental and clinical samples. A guiding protocol presents instructions to the participating student groups. Standard operating procedures are available, but the students are also free to select their own method. The results are methodologically and statistically judged by professional PT-organisers and are presented in the customary way: the dataset, the mean (consensus) value of all participants and the Z-scores. The final presentation of the results takes place in an annual symposium where awards are presented to the best performing student groups, and a lecture programme is presented with subjects in the area of quality assurance and quality control. A selection of results from the KILO/PT/1998-1999 and the KILO/PT/1999-2000 programme is presented.

Review of European Union requirements: quality standards for food analysis laboratories

The European Union has prescribed strict quality standards for official food laboratories and the methods of analysis to be used in laboratories when carrying out official food control work. These requirements, which are based on accreditation, participation in proficiency testing schemes and using validated methods of analysis, are described in detail. The similar approach being taken within the Codex Alimentarius Commission is also outlined. The procedures prescribed will ensure that official food control laboratories have in place the measures to ensure that consistently reliable data can be produced.

Why do food analysts need quality assurance?

Most sophisticated products require testing for compliance with specifications and safety regulations before release into many markets, and trade in many simpler commodities and products also requires supporting technical information. Test documentation has become an essential element in this trade. Food intended for human consumption certainly falls into the "sophisticated products" category. Lack of acceptance of laboratory test data across national borders may be a significant barrier to trade. In order to avoid such barriers and unnecessary duplication of laboratory tests, mutual recognition of laboratory results should be regarded as an important means of facilitating international trade in food products. It is difficult to envisage recognition of test data across borders without internationally agreed criteria for assessing the competence of testing. These criteria should, as a minimum, require that a laboratory involved in the analysis of foods operates a suitable quality system. The laboratory must create a quality system appropriate to the type, range and volume of work performed. It is necessary for the elements of this system to be documented in a quality manual which is available for use by the laboratory personnel. The quality manual must be kept up-to-date by a person or persons having responsibility for quality assurance within the laboratory. This paper describes and discusses the elements of a quality system in a food laboratory, including suitable quality assurance measures, the use of validated analytical methods and participation in proficiency testing schemes.