SPSFAM Heavy Metals ERP Book

AOAC Expert Review Panel for Heavy Metals AOAC OMA Final Action Requirements for 2016.04 Method Author Response

recommended to confirm. For overlapping peaks, caution should be used to integrating as to ensure proper peak identification and peak area assessment. • Include acceptable range Arsenate contamination in the phosphate buffer. o An acceptable concentration of arsenic in the phosphate buffer was added in the Reagents and Standards section, E(h). o “…typically less than 50 ng/g.” • Matrix spikes that include AsB as well as the other species for sample spike. o AsB is used to represent the void volume of the column, primarily to ensure the As(III) is retained and not eluting in the void volume where it could suffer from signal enhancement. AsB is not included in the calibration standards and is not anticipated to be an analyte in a juice matrix and therefore will not be included in the FAPs for routine use. If is this comment is in regards to spiking various other arsenicals into juice samples for method validation, these experiments have been performed, but we are unsure where to include the data. Additional changes 1. Addition of arsenocholine (AsC) to be used as a substitute for AsB; AsC is significantly cheaper than AsB. 2. Addition of part numbers for liquid DMA and MMA standards. 3. Clarify the issues with impurities in the stock standards.

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