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Author Response to Reviewers 071506_OMAMAN-28-AOAC 2006.03_rev 071816
Author Response to Reviewers:
1. Table 6, which is the comparison of the results of certified and consensus values for all
elements included in this study, has been updated to include a bias for both the NIST-SRM 695
and Magruder 2009-06. Please see the attachment for corrections.
2. Table 7, which is demonstrates the method precision and comparability to the 2006.03 method
using some of the original materials and original included elements, has been updated using the
statistician’s suggestion of multiplying the found Horrat value by two. Please see the attachment
for corrections. Please see the attachment for corrections.
3. Table 8, which is the method precision for the proposed included elements (Ca, Cu, Fe, Mg,
and Mn) using some of the original study materials, has been updated using the suggestion from
the statistician of multiplying the found Horrat value by two. Please see the attachment for
corrections.
4. The author recommends a change to the 2006.03 method for the removal from the scope of
arsenic, selenium, and lead due to poor statistics. However, at the time of the publication, it was
the best method available using common equipment found in both state regulatory and
commercial laboratories. The improvement of the added hydrochloric acid to the method will
provide adequate recovery, reproducibility, and trueness of the results lacking in the nitric only
method.
5. Spike method: This method will be changed to a new method and it is not addressed at this
time.
6. Please see the attachment labeled: “Fertilizer Subgroup Metals Statement
Rev_071516_OMAMAN-28-AOAC 2006.03” for further explanations regarding this method.