Modification of the HG-AAS Determination of Arsenic and Mercury in Daily Detergents

In the determination of As and Hg in daily-use detergents by “Hygienic Standard for Cosmetics”, modification for pretreatment of sample was made in 2 respects: ① the sample was digested under programmed temperature control; ② aminosulfonic acid was added into the sample solution obtained to eliminate the interferences of oxides of nitrogen. Linear relationships between values of absorbance and mass concentration of As and Hg were kept in the ranges within 18, 60 μg·L-1, with detection limits (3s/k) of 1.7 μg·L-1 and 0.4 μg·L-1 respectively. Recovery and precision were tested with blank sample by standard addition method, giving values of average recovery of 100% for As and 99.5% for Hg, and values of RSD′s (n=6) of 1.2% and 1.5% respectively.