Scientific Opinion on the safety and efficacy of Maxiban (R) G160 (narasin and nicarbazin) for chickens for fattening

Maxiban (R) G160 is a coccidiostat for chickens for fattening used at levels ranging from 40-50 mg narasin/kg plus 40-50 mg nicarbazin/kg complete feed. Maxiban (R) G160 is safe for chickens for fattening and effective in controlling coccidiosis. The metabolism and residue data for narasin and nicarbazin administered separately have already been described and assessed. Additional information concerning Maxiban (R) G160 indicates that the simultaneous administration of nicarbazin and narasin increases DNC-labelled nicarbazin derived total residues by 20 % (liver) to 50 % (muscle), whereas no modification is observed for HDP-labelled nicarbazin derived residues. There is no evidence resulting from the toxicological studies for any significant interaction between narasin and nicarbazin. The ADI for narasin is 0.005 mg/kg bw, derived from a NOAEL of 0.5 mg/kg bw in a one-year dog toxicity study and applying an uncertainty factor of 100. The ADI for DNC is 0.77 mg DNC/kg bw, based on a NOAEL of 154 mg DNC/kg bw in a two-year dog toxicity study and applying an uncertainty factor of 200. The following MRLs can be applied: 50 mu g narasin/kg liver, kidney, muscle and skin/fat; 15 mg DNC/kg liver, 6 mg DNC/kg kidney and 4 mg DNC/kg muscle and skin/fat. A zero-day withdrawal period is considered appropriate. Maxiban (R) G160 is a slight skin irritant, an eye irritant and a skin sensitiser. The inhalatory risk of users from narasin in Maxiban (R) G160 dust should be reduced by safety measures normally employed for handling dust-generating products. Maxiban (R) G160 would not pose a foreseeable risk for the soil compartment, groundwater or secondary poisoning. However, the risk for surface water could not be assessed.