PROPOSAL
That MRLs for which the available information is insufficient for the JMPR to conclude that the ADI would not be likely to be exceeded be designated as MRLMs (maximum residue limits for monitoring)1.
1
Maximum residue levels for use by government laboratories in their monitoring and/or enforcement activities. The JMPR estimates of dietary exposure based on these residue levels exceed the ADI.
BACKGROUND
The Codex Alimentarius Commission has agreed in principle to recommendations of the 1995 FAO/WHO Consultation2 on strengthening the consideration of risk assessment in the elaboration and use of Codex MRLs, in particular making a clear distinction between risk assessment and risk management responsibilities. The subject was considered further at the 1997 FAO/WHO Consultation on Risk Management and Food Safety3. For pesticide residues in food, Codex has the primary responsibility at the international level for risk management and the JMPR for risk assessment. Both have attempted to implement steps to effect the recommendations of the two Consultations.
2
FAO/WHO. 1995. Application of risk analysis to food standards issues. Report of a Joint FAO/WHO Expert Consultation, 13-17 March 1995. Geneva. WHO/FNU/FOS/95.3 (E.S.T). World Health Organization, Geneva.
3 FAO/WHO. 1997. Risk management and Food Safety. Report of a Joint FA/WHO Expert Consultation, 27-31, January 1997. Rome. FAO, Rome, Italy.
Until recently, estimates by the JMPR of the chronic dietary intake of pesticides have generally been gross over-estimates. Recently introduced procedures using supervised trials median residues (STMRs) and supervised trials median residues for processed products (STMR-Ps) have substantially improved the ability of the JMPR to make better estimates of dietary intake at the international level and thus improve the value of those estimates for risk assessment and risk management decisions.
When the JMPR cannot conclude that the dietary intake will not exceed the ADI (e.g. owing to the lack of sufficient data for the more refined estimation of dietary intake) uncertainty remains as to the toxicological significance of residues in food resulting from the application of pesticides according to GAP. This has resulted in the reluctance of countries to accept some MRLs recommended by the JMPR at the national level, has created risk management problems in Codex, and has the potential to create problems in the use of Codex MRLs in the WTO for the resolution of trade disputes.
Once recommendations by the JMPR for MRLs are taken up in the Codex procedure, the draft MRLs for chemicals whose ADIs might be exceeded are not readily distinguishable from those whose ADIs would not be exceeded according to the dietary intakes estimated by the JMPR. An "implicit" JMPR endorsement is therefore attached to MRLs of both types, although one is clearly a better estimate for risk management decisions than the other. There is clearly a need to ensure that risk managers in Codex and at the national level are able to recognize which dietary estimates have more, and which less, uncertainty. In view of the importance of Codex standards in WTO mechanisms for the resolution of disputes concerning pesticides, the JMPR considers it especially important that its estimates of dietary intake and their relation to the ADI be clearly conveyed to Codex in such a way that potential health concerns are not overlooked.
One approach would be for the JMPR to continue to estimate maximum residue levels when there is insufficient information to determine that the ADI would not be exceeded, but not to recommend them to Codex for use as MRLs. That would provide the strongest incentive for the submission of better data for the estimation of dietary intake. However in some cases this might not be equitable for those countries who are capable of making more refined national estimates of dietary intake than are possible at the international level, or those for which there would be no dietary intake problem simply because their food consumption does not include significant quantities of those commodities which contribute most to the total dietary intake of the pesticide.
Another option (and the one preferred by the JMPR) is to coin another term in order to distinguish those compounds whose intakes can be concluded to be below their ADIs from those for which there is insufficient information to come to that conclusion. The JMPR believes that this approach would better convey the significance of JMPR estimates of dietary intake and would contribute to better risk management decisions within Codex and at the national level. The JMPR therefore proposes a new term: MRLM (maximum residue limit for monitoring), to be defined as an MRL for a pesticide for which an ADI has been allocated, but for which insufficient information has been provided for the JMPR to estimate whether its dietary intake would be below the ADI. The JMPR recommends that MRLMs be applied to new or periodic review chemicals reviewed by future FAO Panels of the JMPR, and that they be clearly indicated as such, and further recommends that the information needed for the JMPR to refine its estimates of dietary intakes continue to be clearly stated in JMPR reports and evaluations.
