ISO 7110:1985

Ammonium bicarbonate (Ammonium hydrogen- carbonate) for industrial use (including foodstuffs) — Determination of lead content — Flame atomic absorption method

A test portion is dissolved in water and acidified with hydrochloric acid. The carbon dioxide is eliminated by heating the solution. The lead is complexed and extracted with a solution of diethylammonium diethyldithiocarbamate in xylene. The solution is aspirated into an acetylene-air flame. The absorption of the 217 nm line or, alternatively, of the 283.3 nm line emitted by a lead hollow-cathode lamp is measured. The method is applicable to products containing more than 0.1 mg/kg of lead.