Accreditation and Standards

Standards used to design this proficiency test :

• Proficiency test Not accredited under UNE-EN ISO/IEC 17043:2023 General requirements for proficiency testing. Check our accreditation scope.
• UNE-EN ISO/IEC 15328:2015 Statistical methods for use in proficiency testing
• HARMONIZED PROTOCOL FOR THE PROFICIENCY TESTING OF (CHEMICAL) ANALYTICAL LABORATORIES
• SANTE Guide into force: ANALYTICAL QUALITY CONTROL AND METHOD VALIDATION PROCEDURES FOR PESTICIDE RESIDUES ANALYSIS IN FOOD AND FEED
• Quick Polar Pesticides Method (QuPPe) latest version.

Why TestQual proficiency test ?

• 20 years of experience in proficiency test s since TestQual's foundation.
• Customized reports: Global report, individual reports, and option for reports by analyte groups.
• Fortification and quality controls available for participants upon request.
• Distributor network: Conveniently place orders in your local language and without worrying about time differences. participation confidentiality is not compromised.
• We take care of everything so you can focus on the analysis.
• Customer service and quick support on all our channels (email, phone, web).
• Innovation and cost-effectiveness: Constant negotiation of shipping costs and materials to ensure your samples arrive in perfect condition and for the best price.

Proficiency test Information

This proficiency test will consist of a single round, in which a sample will be distributed on the specified date (see calendar). Detailed information about this Proficiency test can be found in the protocol (Calendar, sample quantity, analytes, concentrations, deviation/deviations from target standard). The protocol can be downloaded from the right column of this page.

Intercomparison Calendar

Check the right column of this page, in the "Dates" section.

*These dates are indicative and should always be verified with the dates in the Proficiency test protocol and with the news on the TestQual homepage.
Only registered participants in this proficiency test will receive emails with instructions and confirmation of the definitive distribution date.

Analytes

Multiresidue pesticides - QuEChERS

Pesticide control is a very important routine analysis to ensure that foods comply with legislation and are safe for consumption. Laboratories must be able to correctly detect and quantify, among hundreds of possible pesticides, whether an analyte is present in the sample and at what concentration, always avoiding reporting false positives. Maximum Residue Limits (MRLs) for pesticides indicate the maximum amount a matrix should contain so that the presence of these pesticides cannot be a problem for consumer health, to facilitate the marketing of products, and to control the use of plant protection products. The decision regarding MRLs is based on many variables, including toxicological data, metabolism, and persistence in various media. MRLs can be consulted in the annexes of Regulation 396/2005 and an updated list of pesticides and their MRL per matrix can be found. You can check the list of possible pesticides present in the sample in the Proficiency test protocol, which can be downloaded in the right column of this page.

Glyphosate and AMPA

Glyphosate is a wordlwide used herbicide, which has been renewed its at least until 2033 (g5). Glyphosate and other pesticides are mainly used to control weeds that may compete with crops (g1), (g2), thanks to their herbicidal mechanism that kills by inhibiting 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), which is necessary for the production of key components and affects the carbon absorption mechanism for plants (g3). Glyphosate has been determined to be toxic to aquatic life with long-lasting effects (g2), and it is an endocrine disruptor that causes oxidative stress due to excess Ca2+, which alters the reproductive functions of male rats (g4). For glyphosate, in its 2019 review of MRLs for this compound and its derivatives, EFSA considered different residue definitions depending on whether crops were genetically modified to tolerate glyphosate. In this study, the main residue definition was considered as Glyphosate for conventional crops and as "sum of glyphosates, AMPA, N-acetyl-glyphosate, and N-acetyl-AMPA, expressed as glyphosate" for crops genetically modified to better tolerate glyphosate (g4). AMPA is the main metabolite of Glyphosate and has been considered by the EFSA even a better marker of glyphosate usage than glyphosate itself (g4).

Fosetyl-Al

Fosetyl is a polar organophosphorus pesticide commonly used in the form of aluminum salt (Fosetyl-Al). It has fungicidal and bactericidal activity(f1), with widespread use in stone fruit, citrus, and grape plantations, among others. (f2), (f3). Fosetyl tends to degrade into ethanol and phosphonic acid (f1), both in solution and in the fragmentation that occurs in LC-MS/MS (f4). In some media, such as soil, phosphonic acid undergoes photodegradation with the likely product being phosphate (f3). Legislation states that the most appropriate way to express the amount of fosetyl is also taking into account its main metabolite, phosphonic acid. Therefore, the current definition employed by the European Union for this pesticide is Fosetyl-Al (sum of fosetyl, phosphonic acid, and their salts expressed as fosetyl). (f3).

Why participate in a proficiency test program?

Participating in TestQual's proficiency test programs can help you maintain the utmost confidence in your results. The ability of laboratories to analyze and obtain reliable results is crucial for public health. TestQual's proficiency tests provide an opportunity to compare your analysis results with participants from all around the world, allowing you to evaluate your results over time and detect any deviations for prompt correction (specially now that we offer fast evaluation). While a single participation may reveal potential errors, the true value of TestQual's proficiency tests lies in regular and continuous participation, along with each laboratory's internal quality controls, ensuring proper control of the proposed parameters' analysis.

How to register for participation

Laboratories that wish to participate and are not yet registered on our website can do it completing the
REGISTRATION FORM.

If your laboratory is already registered on our website, you can request the participation in this proficiency test by clicking the "Participate" button located both at the top right and bottom of this page. After loggin in, in the PARTICIPATION REQUEST, you must submit your quantification limits of the analytes your laboratory studies. This information is reviewed to ensure the participation will be useful to your laboratory.

Analytes marked as "Not analyzed" (NA) will not appear later, when submitting your data in the results' form. We want to help you focus on the analysis and save you time while giving the best service: you can contact our team and they will give you different options to allow the inscription to this proficiency test, saving time and still ensuring the participation will be useful.
Once the registration is submitted, you will receive an email with your laboratory code for participation in this Proficiency test as soon as possible. Limits of Quantification are requested to ensure that the proficiency test will be useful for you, and in case of any doubts, we would contact you, so you can make an informed decision about your participation. Our aim is to help you showcase your quality.

Contact

If you would like a quote or if we can assist you in any way, you can contact us through:

Thank you very much for your interest/trust in TestQual and our proficiency test programs.