This standard specifies the methods for determination of arsenic in food additives.
This standard is applicable to the determination of arsenic in food additives.
Method I Silver Diethyl Dithio Carbamate Colorimetry
2 Principle
Under the existence of potassium iodide and stannous chloride, resolve the high arsenic in sample solution into trivalent arsenic which, after the nascent hydrogen reaction with zinc granule and acid, generates arsine gas; and after removing the interference of hydrogen sulfide with lead acetate cotton, the gas will be absorbed by and reacted with the solution of silver diethyl dithio carbamate dissolved in triethanolamine-trichloromethane or pyridine and generates a purple red complex which is to be quantified by comparing with the standard.
3 Reagents and Materials
Note: Unless otherwise specified, each reagent used in this method is analytically pure reagent, and the water is Grade 1 water specified in GB/T 6682.
3.1 Reagents
