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M
ASTOVSKA
ET AL
.:
J
OURNAL OF
AOAC I
NTERNATIONAL
V
OL
.
98, N
O
. 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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a
]anthracene
(BaA), and benzo[
a
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