AOAC-RI ERP Book - FAOM METHOD.pdf

M ASTOVSKA ET AL .: J OURNAL OF AOAC I NTERNATIONAL V OL . 98, N O . 2, 2015 503

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Collaborators’ Comments

Most of the study participants commented very positively on the speed and ease of use of the method, especially laboratories FXUUHQWO\ DQDO\]LQJ 3$+V ZLWK PXFK PRUH ODERU LQWHQVLYH DQG WLPH FRQVXPLQJ PHWKRGV The most frequently reported sources of PAH contamination ZHUH VDOWV ZKLFK KDYH WR EH PXIÀHG DQG VWRUHG DSSURSULDWHO\ 6RPH SDUWLFLSDQWV KDG SUREOHPV ZLWK 3$+ VRXUFHV LQ WKHLU laboratories caused by the use of oil pumps in the vicinity of the space used for the sample preparation. As noted above, RQH FROODERUDWRU GLVFRYHUHG 3$+V LQ SRO\SURS\OHQH FHQWULIXJH tubes used for practice sample analysis ( Note $OO WXEHV DQG FRQWDLQHUV XVHG IRU WKH WHVW VDPSOH VWRUDJH DQG SUHSDUDWLRQ ZHUH pretested by the study direction team). 6HYHUDO FROODERUDWRUV LQLWLDOO\ KDG SUREOHPV ZLWK RSWLPL]DWLRQ of the evaporation steps to prevent losses of volatile PAHs. As noted above, the addition of ethyl acetate in the second HYDSRUDWLRQ VWHS UHVROYHG WKLV LVVXH LQ PRVW FDVHV 7KH PDMRULW\ RI VWXG\ SDUWLFLSDQWV XVHG HYDSRUDWLRQ ZLWK D JHQWOH VWUHDP RI QLWURJHQ DW URRP WHPSHUDWXUH RU D PD[LPXP RI ƒ& &ROODERUDWRUV QRWLFHG GLIIHUHQFHV LQ WKH FRORU RI H[WUDFWV RI R\VWHU EODQN YHUVXV IRUWL¿HG VDPSOHV VWRUHG IRU VHYHUDO PRQWKV LQ D IUHH]HU DW ± ƒ& 7KH EODQN VDPSOH SURGXFHG D GDUN JUHHQ H[WUDFW ZKHUHDV WKH VDPH EODQN VDPSOH IRUWL¿HG ZLWK 3$+V JDYH D \HOORZ EURZQ H[WUDFW 7KLV ZDV QRW REVHUYHG IRU R\VWHU VDPSOHV VWRUHG IRU D VKRUWHU SHULRG RI WLPH DQG RU VWRUHG DW ± ƒ& $V GLVFXVVHG EHORZ WKLV REVHUYDWLRQ FRXOG EH OLQNHG WR GHJUDGDWLRQ LVVXHV LQ R\VWHUV $OVR WKH SDUWLFLSDQWV QRWHG WKDW R\VWHU H[WUDFWV ZHUH JHQHUDOO\ GLUWLHU WKDQ VKULPS DQG PXVVHO H[WUDFWV ZKLFK DIIHFWHG FKURPDWRJUDSK\ LQ VRPH FDVHV One collaborator reported the use of a mechanical shaker LQVWHDG RI KDQG VKDNLQJ 0HFKDQLFDO VKDNLQJ LV JHQHUDOO\ SUHIHUUHG E\ URXWLQH WHVWLQJ ODERUDWRULHV DQG WKLV PHWKRG PRGL¿FDWLRQ LV DFFHSWDEOH DV ORQJ DV D YLJRURXV DQG HIIHFWLYH VKDNLQJ XS DQG GRZQ LQ WKH WXEH LV HQVXUHG 7DEOHV ± SURYLGH WKH FROODERUDWLYH VWXG\ UHVXOWV REWDLQHG E\ WKH SDUWLFLSDWLQJ ODERUDWRULHV LQ WKUHH EOLQG GXSOLFDWHV ORZ PLG DQG KLJK IRUWL¿FDWLRQ OHYHO LQ VKULPS PXVVHO DQG R\VWHU 5HVXOWV IURP /DERUDWRU\ 1R DUH SUHVHQWHG RQO\ IRU PXVVHO EHFDXVH WKH 6WXG\ 'LUHFWRUV H[FOXGHG WKHLU R\VWHU DQG VKULPS data sets due to calibration (standard preparation) issues. '03 ZDV XVHG DV D KRPRJHQL]DWLRQ FKHFN DQG was added to blank mussel and oyster samples at 40 and —J NJ UHVSHFWLYHO\ GXULQJ WKH KRPRJHQL]DWLRQ VWHS 7KH PHDQ FRQFHQWUDWLRQ YDOXH REWDLQHG IRU '03 E\ DOO SDUWLFLSDQWV H[FHSW IRU VDPSOH 6)& 0 ORVW E\ /DERUDWRU\ 1R DQG WKH UHVXOW IRU VDPSOH 6)& 0 IURP /DERUDWRU\ 1R ZKLFK ZDV UHPRYHG DV DQ DSSDUHQW RXWOLHU LQ DOO VHYHQ test mussel samples (three blind duplicates and one blank) ZDV —J NJ 56' n ZKLFK FRUUHVSRQGV WR PHDQ UHFRYHU\ RI ,Q WKH FDVH RI R\VWHUV WKH PHDQ FRQFHQWUDWLRQ YDOXH REWDLQHG IRU '03 E\ DOO SDUWLFLSDQWV H[FHSW IRU /DERUDWRULHV DQG IRU ZKLFK DOO '03 UHVXOWV ZHUH HOLPLQDWHG DV RXWOLHUV LQ WKH *UXEEV¶ WHVWV DSSOLHG Collaborative Study Results

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