GC Determination of Isobutyl Nitrite and Amyl Nitrite in Cosmetics

A method of GC for simultaneous determination of two banned esters of nitrous acid (i.e., isobutyl nitrite and amyl nitrite) in cosmetics was proposed. The sample was added with 1.0 mL 20 g·L-1 of sodium sulfite solution and extracted ultrasonically for 10 min with acetone. Two uL of the extract were used for GC analysis, with flame ionization detection (FID). Linearity range of the method was kept between 10.00 to 1 000 mg·L-1, with detection limits (3S/N) of 4 μg·g-1 for isobutyl nitrite and 2 μg·g-1 for amyl nitrite. Tests for recovery were made by standard addition method, giving values of recovery in the range of 87.1%-98.8% and 86.8%-96.9% respectively, with RSD′s (n=9) less than 5.0%.