|Pesticide residues in food - 1997. Report. (FAO Plant Production and Protection Paper - 145) (1998)|
|2. GENERAL CONSIDERATIONS|
In view of the publication of the FAO Manual (see section 2.1), the Meeting considers that the preparation of future submissions will be much more consistent and will further facilitate the evaluation of the experimental data and information provided. In order to assist the efficient and timely estimation of maximum residue levels, some of the deficiencies and problems experienced by the current Meeting in relation to recent submissions are described below.
The Meeting repeatedly found it very difficult or impossible to interpret the summary information on GAP supplied by manufacturers (FAO Manual, 22.214.171.124). The summary should not include any information on the use which is not specifically given on the label (e.g. do not define applications in terms of kg ai/hl if only the kg ai/ha rate is specified; do not specify calculated PHIs if application is authorized only at a specific growth stage; do not give a number of applications calculated from the specified application intervals and PHI). It is stressed (FAO Manual, 3.1.4, para 2) that valid copies of current labels must be provided, together with an English translation of the relevant sections (e.g. dosage, specifying whether the concentration of the spray or the kg/ha rate is primarily defined; application methods; growth stage of plants at the time of application of the pesticide; conditions of use; any restriction of the use). Crops included in groups (e.g. leafy vegetables, fruits) should be individually named. Labels reflecting current GAP should be clearly distinguished from "proposed" labels. Indexing of labels in such a manner as to allow easy cross-reference to GAP summaries and supervised field trials would facilitate the evaluation.
In future, the specific uses of a compound will not be evaluated if the relevant labels have not been provided.
If information on GAP is provided by responsible national regulatory authorities the above detailed information is required and the submission of labels is desirable. The submission of information on GAP by national authorities is especially important in the case of generic pesticides produced by several manufacturers. In such cases information on the chemical composition of technical products and their formulations used in the reporting country is also desirable.
The description of supervised trials (FAO Manual, 3.1.5) should include: the unambiguous description of the commodity, preferably with Codex Classification Numbers; detailed information on sampling and sample preparation with special emphasis on sample size; duration and temperature of storage during successive steps from sampling to analysis; the clear description of the portion of the commodity prepared for the analysis (e.g. measured relative weights of stone and pulp; measured relative weights of peel and pulp if they are analysed separately); blank values; whether the results were adjusted for blank and recovery values (FAO Manual, page 23).
Descriptions of analytical methods should include (FAO Manual, section 3.1.3), but not be limited to, the clear indication of the compound(s) determined, whether they were free or conjugated, the levels of fortification used in the validation of the methods, the limits of determination, and the recoveries obtained.
Processing studies are among the critical supporting studies which are required for the evaluation of a new compound or a periodic review (FAO Manual, 126.96.36.199). The results of processing studies are used for dietary intake calculations and estimations of maximum residue levels where appropriate. Because the studies submitted are often inadequate, guidance is provided in this section of the Manual, where it is stressed that studies which simulate commercial practices as closely as possible are required. Additional studies such as the effects of household jam preparation and small-scale laboratory studies may be submitted as useful supplementary information, but small-scale laboratory studies will not be accepted as a substitute for properly designed and implemented studies simulating large-scale industrial processes. The processing studies should always be on the raw agricultural commodity as it is marketed (e.g. a processing study on residues in fruits should always include the determination of the residues in or on the original unwashed fruits). The studies should be reported according to well-established guidelines such as the US EPA Hazard Evaluation Division's Standard Evaluation Procedure Magnitude of the Residue: Processed Food/Feed Studies EPA 540/9-86-145, or the Commission of the European Communities "Guidelines for the generation of data concening residues as provided as provided in Annex II, part A, section 6 and Annex III, section 8 of directive 911/414/EEC concerning the placing of plant protection products on the market." 1607/VI/97. 7th January 1997.