If you are considering setting this up, you may want to send your samples out. Atomic Absorption Spectrometry (AAS) requires a specialized piece of equipment.
There appear to be several ways of extracting the material to be tested from the food material, and I don't think it matters what the food is. The microwave extraction was used for seafood in the British Standards reference (which you have to pay for to read.)
The FDA has their manual of laboratory methods online only (free).
There is a general method for the microwave digestion of the material (used in an example for mercury in seafood)
Here is a section on AAS after microwave digestion.
There appear to be multiple standard methods that the FDA accepts. All appear to be AAS. It's the best way to analyze for metals. You may have done it in high school, the flame test in the lab Bunsen burner. Or, maybe not, they may have stopped letting kids play with fire in the schools since I was in school, lol.
Did you want to set it up, or just reference it?
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