Residue chemistry and laboratory performance and evaluation

The National Residue Survey (NRS) contracts the services of Australian and New Zealand laboratories to perform residue testing. The laboratories must have demonstrated capabilities in the specific chemical residue analyses that are required by export and domestic markets.

Selection of laboratories

Laboratories contracted for NRS work are selected based on value for money via a tender procurement process. The essential elements of the selection process are:

• proven analytical proficiency
• organisation and methodology
• knowledge/experience, staffing and facilities
• organisational capability
• previous performance and referees
• price and costs to the Department.

The NRS requirements for satisfactory laboratory performance include achievement of the NRS limit of reporting (LOR) specified for each chemical-commodity combination. Any laboratory may participate in the procurement process, providing they meet the mandatory conditions for participation in the NRS tender.

Laboratory performance evaluation (LPE)

NRS laboratory performance evaluation activities, generally based on proficiency testing (PT), seek to make regular and objective evaluations of contract laboratory competency. They are designed to maintain an up-to-date and continuing assessment of the proficiency of laboratories that are analysing samples for NRS or seeking to offer such services in the future.

We recognise the suitability of laboratories for export testing of produce based on such demonstrated competency. Laboratory performance evaluation also helps to ensure the quality of the analytical testing service delivered to participating industries.

Participating in proficiency testing

NRS contract laboratories are required to participate in all relevant, scheduled PT conducted by the NRS for the entire contract term.  In addition, NRS PT is open to any other Australian laboratory currently testing chemical–commodity combinations included in the NRS suite of programs for which an NRS PT program is offered. Overseas laboratories may also participate where circumstances permit (e.g. stability of chemicals, import conditions, courier requirements).

Participation in NRS PT is free of charge, however in the case of overseas laboratories, additional charges may apply to cover courier costs and phytosanitary certificates.

Role of the Laboratory Performance Evaluation Committee

The primary role of the LPE Committee is to advise on the PT schemes run by the NRS. The LPE Committee examines analytical PT results and their statistical interpretation, where relevant, to rank laboratory performance.

Members of the LPE Committee may also provide feedback on the planning and implementation of proficiency tests, and perform random audits of individual participant results.

National Association of Testing Authorities (NATA) accreditation

The NRS is accredited by the NATA as a Proficiency Scheme Testing Provider as assessed against ISO/IEC 17043, but is not itself a laboratory accreditation body. The NRS recognises and supports the role of NATA as the principal agent of laboratory accreditation, and the relevant nationally and internationally defined standards.

NATA accreditation (or international equivalent) is generally required by any laboratory providing chemical analytical services to the NRS. However, the NRS does not require a laboratory to hold (or be seeking) NATA accreditation, either in a particular test or in chemical residue analysis, as a precondition of participation in NRS PT. Where appropriate, participation in the NRS PT may assist in gaining or maintaining of its accreditation.

In the case of overseas laboratories, the NRS recognises accreditation by bodies that are signatories to the International Laboratory Accreditation Cooperation (ILAC) Mutual Recognition Arrangement (often referred to as the ILAC Arrangement).

Laboratory procurement process and future contracts

All information relating to provision of chemical analytical testing for the NRS can be accessed through AusTender. The 12th term contracts run from 1 July 2019 to 30 June 2022, with the possibility of extension to 30 June 2024.

The 12th term contracted laboratories and their respective testing programs are listed below, along with new analytical testing programs that have been established since 1 July 2019:

Testing and reporting of results

For the information of laboratories wishing to undertake contract work, the NRS specifies and publishes LOR values for each chemical–commodity combination required for NRS tests. These values are published in the 'National Residue Survey Proficiency Tests Handbook' (available from NRS on request).

Laboratory method LORs would generally be expected to be less than or equal to the NRS specified values. A contract laboratory must report quantitative results for analytes detected above the laboratory's method LOR, irrespective of the level at which the NRS LOR has been set. Detections of an analyte above the laboratory's method LOD, but less than the laboratory's method LOR, must also be reported.

All analytes reported at or above the laboratory's method LOD must have been identified in a manner consistent with the criteria outlined in the European Commission Decision 2002/657/EC (available from NRS on request).