Determination method comparison of lead,cadmium and copper in tea

he content of lead,cadmium and copper in tea standard material were determined.There were two pre-treatment methods as follows:dry digestion and microwave digestion.The measured values of tea sample which processed by these two pre-treatment methods were contrasted respectively.The results showed that the microwave digestion was accurate;the measured values of lead,cadmium and copper were in the standard value range,and good recovery,lead recovery was 93.3%～106.7%;cadmium was 95.2%～103.2%;and copper was 100.0%～103.2%.