加圧酸分解/黒鉛炉原子吸光分析法による愛玩動物用飼料(ペットフード)中のカドミウムの定量

Abstract

In the present study, we attempted to determine trace cadmium in a dry-type cat food by using a method combining pressure acid decomposition and graphite furnace atomic absorption spectrometry. Carbon soot generated from the remaining organic matter caused a large background absorption at the atomization in the graphite furnace. The background was effectively suppressed by flowing a small amount of argon, which is the purge gas to prevent exhaustion and deterioration of the graphite furnace, also during the atomization. The average of the quantitative values of cadmium obtained by three times of analyses was 0.85 micrograms g(exp -1), and the relative standard deviation was 3.5%. The quantitative value decreased to ca. 70% only by raising the sample decomposition temperature by 10 C. This result showed that the careful consideration was required to set the conditions of the samples decomposition. For further development of the present study, it is also necessary to verify the accuracy of the proposed method by using certified reference materials for food analysis.