AOAC-RI ERP Book - FAOM METHOD.pdf

AOAC RESEARCH INSTITUTE AOAC OFFICIAL METHODS OF ANALYSIS (OMA) OMAMAN-15 : Determination Of Polycyclic Aromatic Hydrocarbons (PAHs) In Seafood Using Gas Chromatography-Mass Spectrometry: A Collaborative Study* Study Director: Katerina Mastovska, Covance Laboratories Inc., Nutritional Chemistry and Food safety, 3301 Kinsman Boulevard, Madison, WI 53704, USA case with SRM 1974 available, it could have been handled differently. The selection of the 19 target PAHs to determine could be questioned. The authors comment on criteria for separation of chrysene and triphenylene and also BaP and BeP, which is good, but perhaps triphenylene and BeP should have been included. There were no performance criteria for the separation of the alkyl-PAHs from potential isomers, e.g., with 3-MeChr targeted, how do you know if you are separating it from other methylchrysene or methyl-BaA isomers? The inclusion of several alkyl-PAHs is good, but will this really provide a method to look at the alkyl-PAHs, which in petroleum contaminated samples may be more abundant than the parent PAHs. Should there be a provision for looking at the alkyl-PAHs as a group by MS? Perhaps this is beyond the intended scope of this method. ER 7 Fish, one of the most common seafood, was not covered in this method. Oyster needs to be stored at -70 C, which is not very easy for many labs to maintain. ER 8 no comment ER 1 Great summary of results and provided complete statistical information. Would like to see more on linearity results. ER 2 The supporting data indicates that the method is rugged and accurate. ER 3 Nicely organized. ER 4 na ER 5 More specificity needed in quantitative parameters. ER 6 In general, this is a good method, but needs further validation. ER 7 Tested real samples. Additional experiments with shrimp matrix performed. ER 8 good Supporting Data Comments

Method Optimization

ER 1 ER 2 ER 3 ER 4

N/A

Was well described and performed appropriately.

Good.

na

ER 5 The Safety Section must be in the front of the method since safety is more important than any other part of the protocol. Method must be more specific when outlining quantitative parameters. Under Degradation Issues on page 18, the discussion emphasizes the need for a Stability Study. 18.2 megaohm water should be used for any GC/MS method (page 9, Section C). Need a statement that documented calibrations/reference checks were performed on all analytical equipment and instrumentation used in the collaborative study. ER 6 The method optimization is well done in particular the SPE cleanup. Could the use of an aminopropyl SPE be less sensitive than silica regarding deactivation by moisture content? ER 7 Elution solvent volume for silica gel SPE cleanup is optimized. Increased water amount (10 mL) is used in shrimp samples to help shake and extract PAHs from more viscous shrimp samples. ER 8 good