Studies For Determination Of Se, As And Hg In Animal Foodstuff By Hydride Generation Atomic Fluorescence

Along with the development of industry and agriculture, heavy metal pollution has become a growing worldwide concern. The noxious substance was absorbed by anthropometric through food chain, which would lead to people's intoxication. Now with the development of research, people think much more highly of heavy metals than ever before, and are paying much more attention to metal residue problems. How to detect and control metal contamination has become a popular question. Animal food is an important origin of metal in human body, so to find out a simple, quick, precise method to detect the metal content in chicken, pork, milk and eggs is very significant.Atomic fluorescence spectrometry is an analytical technique, which was developed in 1960s'. The technique has many virtues, such as simple spectral line, high sensitivi- ty, low detection limit and multi-element analysis. We use it to detect arsenic, seleni- um and mercury. But there is no national standards issued for dual-channel detection of arsenic and mercury, arsenic and Se, mercury and Se.Microwave oven which heats samples by the principle of molecular collision and controlls pressure by indutor, is safe, efficient, and has no pollution, so it is very popular to analysts. Arsenic selenium and mercury can be lost easily with the utilization of uncovered digestion, for their high evaporability.This study was to optimize the conditions for single-element detection, and on the basis of it, we searched for the conditions of double-element measurementm, in order to improve work efficiency and lower the analysis cost. We did the following work by using AFS-920 and microwave digestion systems. To perfect the detection conditions and increase detection sensitivity, we performed experiments to choosed the best pre-treatment methods, reductant concentration, instrument performance parameter, and counter-interference reagent.Through analyzing a large amount of data and test records, we explored the best conditions of double-element detection. The proposed method was provided with linear response ranges from 0 to 10μg/L for As and 0 to 1.0μg/L for Hg, and the detection limits of 0.0236μg/L and 0.0061μg/L were obtained for As and Hg respectively. The precision is 1.91% and 2.16% (R.S.D., n = 11). The proposed method was provided with linear response ranges from 0 to 10μg/L for As and 0 to 10μg/L for Se, and the detection limits of 0.0056μg/L and 0.0326μg/L were obtained for As and Se respectively. The precision is 1.95% and 3.26% (R.S.D., n = 11).The established dual-channel detection met- hod of two elements achieved better sensitivity, precision and accuracy, without mask- ing agent, separation. And this method was valuable in practical analysis.