Scientific opinion on the modification of authorisation of Deccox® (decoquinate) as feed additive for chickens for fattening
Deccox® contains decoquinate as the active substance for prevention of coccidiosis in poultry. The applicant requested a reduction in the withdrawal time from three days to zero days and the introduction of maximum residue limits (MRLs) for liver (1.0 mg/kg), kidney (0.8 mg/kg), muscle (0.5 mg/kg) and skin/fat (1.0 mg/kg). Decoquinate is not genotoxic and is not carcinogenic. The lowest no observed effect level (NOEL) was 15 mg/kg bw per day, observed in a 12-week oral toxicity study in dogs. The acceptable daily intake (ADI) of decoquinate (already established by the FEEDAP Panel in 2003 and since confirmed) is 0.075 mg/kg body weight (bw), based on the above NOEL, applying an uncertainty factor of 200. On the basis of new metabolism/residue studies in chicken and rat, major metabolites appear to be dissimilar in these two species. Nevertheless, the assessment of consumer safety refers to the ADI of decoquinate, considering the limited exposure of consumers to metabolites from chicken tissues. Decoquinate is the marker residue. A conservative estimate of consumer exposure, based on total residues measured after two and six hours withdrawal, indicates that it would be about 2 % of the ADI. Since a withdrawal period of two and six hours corresponds to a zero withdrawal time under practical husbandry conditions, a zero days withdrawal time does not compromise consumer safety. The new residue data submitted confirm that no MRLs are considered necessary.