SPSFAM Arsenic Speciation ERP

In the Matrix Specific Repeatability, Reproducibility and Recovery Studies table for Grape Juice, the

values listed for arsenite are <LOQ according to the LOQs listed in Table 2015.01H. The values listed for

MMAs are < 0.068 µg/kg. This conflicts with the LOQ listed in Table 2015.01H of 3.1 µg/kg. This is almost

2 orders of magnitude difference. In the same table but for Baby Cereal, 4 out of 8 sections of data have

< LOQ reported and, hence, no statistics. Samples with species > LOQ should have been used for the

SLV.

There were no example chromatograms. An analyst not familiar with the method should know what

order the peaks elute and what an example chromatogram should look like.

There was no accuracy data for arsenite and arsenate but rather only for total inorganic arsenic.

Therefore arseneite and arsenate should be removed from the applicability statement.

There was no data for juice concentrate in the Matrix Specific Repeatability, Reproducibility and

Recovery Studies section. Therefore juice concentrate should be removed from the applicability

statement.

There was only one reference material to judge accuracy. Two or more CRMs would have been better.

There was no information on how the Reproducibility and Recovery Study data was obtained such as

how many analysts and instruments were involved, over how many days were the data collected and

were the days consecutive.

There was no ruggedness data.

Method Optimization:

No data

Performance Characteristics

Analytical Range:

Juice - 0.5 ppb to 0.5 ppm Fails SMPR upper range of 1 ppm

Juice concentrate - 2 ppb to 2 ppm

Rice and rice Products - 6.7 ppb to 6.7 ppm

LOQ:

Difficult to tell what is the LOQ. Table 2015.01H lists values but the values are the same for juice

and rice even though these sample types have different prep dilutions.

Accuracy/Recovery:

Accuracy based on SRM 1568b was excellent for TIAs (99%), MMAs (99%) and

DMAs (100%). Note that there was no data for arsenite and arsenate individually.

Precision (RSD

Generally in the 1% to 5% range for the 4 matrix types. Exceptions outside of SMPR

requirements were baby cereal and rice for arsenate (both at 25%).