Do you need control materials to validate your methods or carry out your quality control?

M1: Acetamiprid (µg/kg), Benalaxyl (µg/kg), Bromopropylate (µg/kg), Carbaryl (µg/kg), Cypermethrin (µg/kg), Chlorpyrifos (µg/kg), Chlorpyrifos-methyl (µg/kg), Deltamethrin (µg/kg), Difenoconazole (µg/kg), Diuron (µg/kg), Etion (µg/kg), Kresoxim-methyl (µg/kg), Linuron (µg/kg), Malathion (µg/kg), Methidathion (µg/kg), Methomyl (µg/kg), Pirimicarb (µg/kg), Prometryn (µg/kg), Propamocarb (µg/kg), Propoxur (µg/kg)(1), Simazine (µg/kg), Tebuconazole (µg/kg), Tetradifon (µg/kg), Thiabendazole (µg/kg), Thiacloprid (µg/kg), Vinclozolin (µg/kg)