6.5. Effects of processing U.K.
6.5.1. Nature of the residue U.K.
The objective of studies on the nature of the residue shall be to establish whether or not breakdown or reaction products arise from residues in the raw agricultural commodity during processing, which may require a separate risk assessment.
Circumstances in which required U.K.
Studies on the nature of residues in processing shall be provided where residues in products of plant or animal origin subject to processing may occur at a level of or higher than 0,01 mg/kg (based on the residue definition for risk assessment for the raw commodity). No studies shall, however, be required in the following cases:
substances with a water solubility < 0,01 mg/L;
only simple physical operations, not involving a change in temperature of the commodity are carried out, such as washing, trimming or pressing; or
the distribution of residues between pulp and inedible peel is the only effect of processing.
Test conditions U.K.
Depending upon the expected level and chemical nature of the residue in the product of plant or animal origin, a set of representative hydrolysis situations simulating the relevant processing operations shall be investigated, where appropriate. Consideration shall also be given to the effects of processes other than hydrolysis and the potential for the formation of toxicologically significant breakdown products.
The studies shall be conducted with one or more radio-labelled forms of the relevant substance.
6.5.2. Distribution of the residue in inedible peel and pulp U.K.
The objectives of studies concerning distribution of the residue in inedible peel and pulp shall be:
to determine the quantitative distribution of residues between inedible peel and pulp,
to estimate peeling factors, and
to allow a more realistic estimation of dietary intake of residues.
Circumstances in which required U.K.
These studies shall be provided for plant products where the peel is either inedible (such as melons, bananas) or is very rarely entirely eaten by consumers (such as citrus fruit).
Test conditions U.K.
These studies shall be performed as part of supervised residue trials, the number of results reported depending on the number of residue trials conducted. Special attention shall be paid to possible contamination of the pulp. Precautionary measures shall be taken in order to quantify a realistic highest residue level.
6.5.3. Magnitude of residues in processed commodities U.K.
The main objectives of studies concerning magnitude of residues in processed commodities shall be:
to determine the quantitative distribution of residues in the various processed commodities used as food or feed,
to estimate processing factors, and
to allow a more realistic estimation of dietary intake of residues.
Circumstances in which required U.K.
The following points shall be taken into consideration when deciding whether it is necessary to carry out processing studies:
the dietary burden of a processed product in the human (such as apples) or animal diet (such as apple pomace);
the level of residue in the plant or plant product to be processed (normally ≥ 0,1 mg/kg);
the physical and chemical properties of the active substance and its relevant metabolites (such as fat-solubility in case of oil seed processing); and
the possibility that breakdown products of toxicological significance may occur after processing of the plant or plant product.
If the level of residues is less than 0,1 mg/kg, processing studies shall be carried out if the contribution of the commodity under consideration to the theoretical maximum daily intake (TMDI) is ≥ 10 % of the ADI or if the estimated daily intake is ≥ 10 % of the ARfD for any European consumer group diet.
Processing studies shall not be required if plants or plant products are exclusively used raw (unprocessed) for food and feed purposes.
In some cases, a simple calculation shall be sufficient to determine the processing factor such as concentration from dehydration or dilution factors, as long as the process under consideration is not expected to have an influence on the nature of residues.
Industrial processing U.K.
If the properties of the active substance, the impurity or the metabolite, as appropriate, indicate that it might concentrate in a given processed fraction, then a processing study shall be necessary even in situations where the residue in the plant or plant product to be processed is lower than 0,1 mg/kg. In such cases, exaggerated application rates up to 5 × or shortened PHIs shall be applied where necessary to achieve a quantifiable residue in the plant or plant product to be processed. A processing study shall not be required if exaggerated application rates (up to 5 ×) fail to yield a quantifiable residue in the plant or plant product to be processed. Phytotoxicity shall be considered when contemplating exaggerated rate treatments.
Domestic processing U.K.
For domestic or home transformation processes and minor industrial ones, when no residues are found at or above 0,1 mg/kg in the raw agricultural commodity at recommended GAP from supervised field trials conducted at the maximum label rate and minimum PHI, no processing studies shall be required.
Test conditions U.K.
Processing studies shall represent domestic preparations (for example cooked vegetables) or commercial industrial processes (for example production of apple juice). Processing studies shall be carried out at least on a representative crop of a crop group, where use is envisaged. The choice of the crop and of the process shall be justified and explained.
The technology used in processing studies shall correspond as closely as possible to the actual conditions that are normally used. For each crop to be investigated two studies per process shall be carried out to determine concentration and dilution factors in processed commodities. If more than one processing method is in use, the one which is expected to give the highest residues in the processed product for human consumption shall be chosen. The results shall be extrapolated to all crops within a crop group undergoing the same process.
When the results (processing factor) of the two studies differ in the main processed products by more than 50 %, further studies shall be provided to derive a consistent processing factor.
Additional studies shall be carried out if, when using processing factors derived by extrapolation, the estimate of the dietary intake exceeds the ADI or ARfD. Those studies shall be carried out on major processes and commodities which contribute most to the ADI/ARfD exceedance.