REP11/PR JOINT FAO/WHO FOOD STANDARDS PROGRAMME ...

REP11/PR 3
2.6 Statistical calculation of MRLs
19. The Committee noted that the March 2010 version (30/03/2010) of the OECD MRL Calculator was provided to JMPR for use
at its 2010 Meeting (in conjunction with the current NAFTA Calculator). Further comments were provided based on JMPR
experiences in using the calculator. The Meeting concluded that the tested version of the OECD Calculator is a helpful tool to
supplement expert judgement and to promote consistency in the elaboration of MRLs.
20. The Delegation of the EU shared the view of the JMPR that the OECD MRL calculator is a valuable tool supporting the
experts in deriving MRL proposals. However, expert judgment is also important, in particular in cases where the number of trials data
is limited and the residue trials do not fully reflect the critical GAPs.
21. The Delegation of Australia informed the Committee that the OECD MRL Calculator has been approved and published by
OECD.
22. The Committee agreed to recommend JMPR to use the OECD calculator as a tool to support expert judgment when
proposing MRLs.
2.7 Appropriate value from replicate samples from a supervised field trial for use in statistical calculation of the MRL
estimate
23. The Committee noted that the JMPR had reconsidered its practice of using the highest value from replicate samples of a
given field trial and from 2011, would use the average of replicate field trial residue values in establishing the data set for statistical
calculation of maximum residue level estimates. However, JMPR also noted that the interpretation of the estimate must take into
account individual replicate values contributing to the data set that exceed the estimate. The Committee supported this new
approach.
2.8 The application of proportionality in selecting data for MRL estimation
24. In order to increase the size of the residue database supporting an MRL, the possibility of use a proportionality approach
when selecting data for MRL estimation was identified by the JMPR based on the analysis of 10 years residue trial data. The
Meeting decided it would only consider the method of proportionality under certain conditions, as outlined in Chapter 2.8 of the 2010
Report. Further discussion was scheduled under Agenda Item 6.
2.9 Further consideration of expert judgement in evaluating residue trials
25. The Committee noted that a new approach was discussed by the JMPR for the prediction of pesticide residue concentrations
in food and feed commodities from foliar-treated crops based on zero day data. The approach was used as an adjunct to other
considerations and statistical calculations in estimating maximum residue levels.
2.10 Use of the OECD Feed Table
26. The Committee was informed that some further modifications of the OECD feed table has been made by JMPR to avoid
situations where commodities with unique codes might be treated as separate feed items. The 2010 JMPR replaced the Codex
Commodity Codes allocated to the OECD feed items by the more general Codex Group Codes and corrected some of the Codex
Group Codes allocated by the 2009 JMPR. It was noted that these changes did not impact on the existing Codex Classification
System, nor on the OECD feed table.
2.11 Training of scientists from developing countries for the establishment of pesticide maximum residue levels in foods
and assessment of the risk from dietary intake of residues
27. The Committee was informed that the FAO JMPR Panel developed a Training Manual to meet the need of developing
countries for training in the evaluation of pesticide residues. The Training Manual is intended for use at training workshops and also
for self-guided study. The Training Manual was used in the international training course held by FAO in November 2010. More
regional workshops have been scheduled in 2011 based on the successful experience of the first international training.
28. Many countries, in particular developing countries, expressed their appreciation to FAO for its effort in developing the Training
Manual and conducting training courses fostering a better understanding of establishment of pesticide maximum residue levels in
foods and assessment of the risk from dietary intake of residues. The Committee encouraged FAO and WHO to continue to provide
such technical support to member countries.