First draft prepared by
Dr. Robert C. Livingston
Center for Veterinary Medicine
Food and Drug Administration
Rockville, MD, USA
ADDENDUM
to the Spiramycin residue monograph prepared by the 47th meeting of the Committee and published in FAO Food and Nutrition Paper 41/9, Rome 1997
Background
The Forty-seventh Session of the Committee recommended the following MRLs for spiramycin in cattle, chickens and pigs.
|
Muscle |
(cattle, pigs, chicken) |
200 m g/kg |
|
Liver |
(cattle, pigs, chicken) |
600 m g/kg |
|
Kidney
|
(cattle, pigs) |
300 m g/kg |
|
(chickens) |
800 m g/kg |
|
|
Fat |
(cattle, pigs, chicken) |
300 m g/kg |
|
Milk |
(cattle) |
100 m g/l |
For cattle and chickens MRLs are expressed as the sum of spiramycin and neospiramycin, for pigs as spiramycin equivalents (antimicrobially active residues).
The 10th Session of the Codex Committee on Residues of Veterinary Drugs in Foods advanced the recommended MRLs for muscle, liver, kidney and fat (cattle and chickens) and muscle (pigs) to Step 8. The Codex Committee advanced the proposed draft MRLs for pigs (liver, kidney, fat) to Step 5/8, by omitting Steps 6 and 7, as these were modifications of previous assessments which presented no additional toxicological concerns. The Codex Committee also advanced the MRL of 100 m g/l for cattle milk to step 8. It noted proposals to increase this MRL to 200 m g/l and requested that the Expert Committee re-evaluates the MRL for cattle milk at its 48th meeting to determine, if it could be raised to 200 m g/l. The Codex Committee requested the Expert Committee to advise the Codex Alimentarius Commission of its opinion on raising the MRL from 100 m g/l to 200 m g/l, and indicated that it would support such an increase on the basis of that opinion.
Using the MRLs for chickens (which results in the largest theoretical maximum daily intake) and a standard daily intake of 300 g muscle, 100 g liver, 50 g kidney, 50 g fat and 1.5 litres of milk, the theoretical maximum daily intake of antimicrobially active spiramycin residues is 440 m g. Using an ADI of 0-50 m g/kg of body weight, a 60-kg person would therefore be permitted to consume 3000 m g/kg of antimicrobially active spiramycin residues. Therefore, the maximum daily intake of spiramycin residues of concern would use 14.7% of the ADI. If the MRL for cattle milk were increased to 200 m g/l, the theoretical maximum daily intake would increase to 590 m g or 19.7% of the ADI.
Table. Theoretical maximum daily intake (TMDI) of antimicrobially active spiramycin residues
|
Tissue |
MRL (m g/kg) |
Daily Intake of Tissue (g) |
Ratio TR/MR |
TMDI (m g) |
|
Muscle |
200 |
300 |
1 |
60 |
|
Liver |
600 |
100 |
2 |
120 |
|
Kidney |
800 |
50 |
2 |
80 |
|
Fat |
300 |
50 |
2 |
30 |
|
Milk |
200 m g/l |
1.5 litres |
1 |
300 |
|
Total |
|
|
|
590 |
TR = Total antimicrobially active residues; MR = Marker residues
Maximum Residue Limits
The Committee recommended that the MRL for milk be increased from 100 to 200 m g/l.
