AOAC-RI ERP Book - FAOM METHOD.pdf

ASTOVSKA

ET AL

OURNAL OF

AOAC I

NTERNATIONAL

98, N

. 2, 2015

503

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cleanup, and evaporation) away from oil pumps, such as

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material, and equipment may also be sources of PAHs,

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actual procedure can release potentially present PAHs into the

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mixture. For this and other potential contamination reasons, it is

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batch.

In addition to the contamination issues, another problem

faced by laboratories less experienced in PAH analysis was

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of volatile analytes, especially naphthalene. Isooctane is used

as a keeper in both evaporation steps, but it did not prevent

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step in certain laboratories. For this reason, the study direction

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which helped in most cases and was added as a recommendation

to the method procedure.

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10 of them (listed in the

Acknowledgments

section) completed

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many cases, the reason why a participant did not complete the

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ability to qualify for the study.

Collaborators’ Comments

Most of the study participants commented very positively on

the speed and ease of use of the method, especially laboratories

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The most frequently reported sources of PAH contamination

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laboratories caused by the use of oil pumps in the vicinity of

the space used for the sample preparation. As noted above,

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tubes used for practice sample analysis (

Note

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pretested by the study direction team).

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of the evaporation steps to prevent losses of volatile PAHs.

As noted above, the addition of ethyl acetate in the second

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One collaborator reported the use of a mechanical shaker

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Collaborative Study Results

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data sets due to calibration (standard preparation) issues.

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was added to blank mussel and oyster samples at 40 and

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test mussel samples (three blind duplicates and one blank)

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BaP

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]anthracene

(BaA), and benzo[

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