(A) Revision of Recommended Methods of Sampling for the Determination of Pesticide Residues
(B) Revision of the List of Recommended Methods of Analysis for Pesticide Residues and Other Matters Related to Methods of Analysis for Pesticide Residues
91. The Committee considered the referenced documents with the assistance of the ad hoc Working Group on Methods of Analysis chaired by Dr. van Zoonen (The Netherlands), which had considered the government comments submitted at Step 6 on the Draft Revised Methods of Sampling for the Determination of Pesticide Residues for Compliance with MRLs.
92. A number of delegations supported the advancement of the Draft Revised Methods to Step 8. However, the Delegation of New Zealand was strongly of the opinion that the text should not be advanced due to significant differences in how MRLs were set by the CCRVDF/JECFA and CCPR/JMPR, and requested that if the text was to be advanced, a statement be inserted to the effect that the text would not apply to compliance with EMRLs and veterinary drugs uses. The Committee agreed to amend the term “mixed” in Table 1 of the document to “well mixed”.
93. The Committee agreed to advance the amended Draft Revised Methods[26] to Step 8 for adoption by the Commission noting the strong concern of New Zealand which reserved its position. To promote harmonization within Codex, it also agreed to bring the amended text to the attention of the CCMAS and CCRVDF for consideration. Being aware of the importance of harmonization, the Committee felt that in the future it might propose development by the Commission of a mechanism for ensuring harmonization, as appropriate, throughout Codex.
Revision of the List of [Recommended] Methods of Analysis
94. The Committee generally supported the update of the list and preferred the title of the document being “List of Suitable Methods of Analysis” or omitting any adjective. The Committee was informed of the ongoing work by AOAC International on validation of methods for pesticide residues.
95. The chairperson of the Working Group offered to evaluate the current list against the Criteria contained in the Procedural Manual and the existing List[28]. It was agreed that information would be sought by means of a Circular Letter on which of the methods listed were still commonly used.
Analytical implications of the residue definitions of abamectin (177) dicofol (26), captafol (6), captan (7) and folpet (41)
96. The Committee was informed of difficulties implied by the inclusion of the delta 8,9 isomer of abamectin B1b and its parent compound in the residue definition of abamectin due to the unavailability of analytical standards. For dicofol, captafol, captan and folpet, the Working Group expressed its preference for the inclusion of degradation products formed during the analytical procedures into the residue definitions. Several delegations expressed views on whether or not degradation products should be included in the residue definitions. The Committee agreed to seek information from government laboratories on national practices in testing these compounds for compliance with MRLs and recommended that these submissions on specific compounds be sent to the JMPR at the time of Periodic Review. The Committee noted that folpet was scheduled for Periodic Review by the 1998 JMPR.
Problems associated with the analysis and expression of residue data for fat soluble pesticides in milk and meat
97. In response to the referral of the JMPR[29], the Working Group recommended that MRLs for fat-soluble pesticides in meat should apply to the lipid portion of the fat from any part of the animal, unless otherwise indicated in the MRL description. Within this definition, the fat could include trimmable fat or fat obtained by rendering or extracting lean meat. The Committee noted that incorrect results would be obtained in analyzing milkfat and converting it into a whole milk basis using 4% fat content, if the actual fat content was very different from 4%.
98. The Committee decided to send this information to the JECFA along with the relevant report section of the 1997 JMPR for consideration; and to seek information from governments on their current practices for consideration by the JMPR.
Guidelines on in-house validation of analytical methods for monitoring pesticides in food stuffs
99. The Committee noted that due to accreditation requirements, in-house validation had gained great importance. Regarding the Working Group’s recommendation that a section on validation of methods in the Guidelines on Good Laboratory Practice in Pesticide Residue Analysis[30] should be revised, the Committee requested the Delegations of the Netherlands, Australia and the United Kingdom to prepare a discussion paper on this issue for discussion at the next Session. Noting that a paper would be prepared for the next Session of the CCMAS on this issue, the Committee stressed the need for harmonization and coordination[31]. The Committee was informed of the AOAC guidelines for methods validation.
100. The Committee agreed that a working group should convene at its next Session under the chairship of Dr. van Zoonen.
