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<br />Table 1. Quality COIltrol results from. (a) MURRforthe:analysis of
<br />fish muscle plug sampleS.byneulron activation,and(b)ETSRC for
<br />fish muscle samp1es which were acid digested and analyzed by hydride
<br />generation atomic absorption . . ,
<br />(a) MURR
<br />
<br />QCType
<br />
<br />IAEAFiShFlesh'" ;;
<br />IAEAFtsh 8Olub;-
<br />NIST'Tuna.RM'SO"
<br />MSC Strip:"BasS""
<br />NIST Bovine 'Liver'" .
<br />NiST BovitieLive?""
<br />NISTBoVine uver"
<br />'NIST Bovine Liver!' >f
<br />NIST Bovine Liver"
<br />
<br />
<br />"r:J
<br />
<br />-blind QC submitted from Mid~est Science Center
<br />banalyzed by MURRas part of internal QC Progralll
<br />c:!:2 x standard error of the mean '
<br />d uncertainty limits of the ovefa1J. mean (~. = 0.95)
<br />e :!:95% confidenoclimit
<br />f :!:standard deviatioo from the mean
<br />. I MURR = Missouri Research Reactor; IAEA = International Atomic
<br />Energy Agency; NIST'=, National Institute of Standards and Technol-
<br />ogy; MSC = Midwest Science Center
<br />
<br />(b) ETSRc;d
<br />
<br />QCType Acceptable
<br />n Range limits
<br />procedural blanks 4 < 0.2 fJ.g1g <LODb
<br />duplicates '3 < 6.1 RPoa < 10 RPD
<br />pre-digestion spikes 3 96 - 115% Recovery 80% - 120%
<br />NIST Oyster 15668 2 1.9;2.0 2.21 :!: 0.24c
<br />NIST Liver 1517a 3 0.6310 0.17 0.71 :!: O.O-r'
<br />
<br />& RPD => relative percent difference
<br />b less than method limit of detection
<br />c :!:95% confidence limit
<br />
<br />theSe analyses are shoWn in Table la. Recovery of selenium for
<br />three offourtissue.control materials submitted as blind samples
<br />was excellent; results were within or very close to the recom-
<br />mended .or certified range for selenium. However, one mate-
<br />rial, IAEA (International Atomic Energy Agency) Fish Solu-
<br />bles, exhibited poor recovery. This material contained an
<br />abnormal amount of sodium and chlorine, which requiredre-
<br />analysis and counting in a different geometry. Thus, the results
<br />for this control material may be eliminated from consideration
<br />because its matrix was significantlydifferentfrom.the submit-
<br />ted samples so as to require a change in the irradiation method-
<br />ology. Method precision, determined from NIST bovine liver
<br />tissues analyzed by MURR as part of itsmtemal quality control
<br />program, was 5.3 percent relative standard deviation. The limit
<br />of detection for'theSe77mnu:thod,ba.Sedon a'~mg sample
<br />weight, was O.OlSf.Lglgseleniurii:'"
<br />
<br />
<br />Quality .Control - Selenium by Hydride Generation .
<br />Atomic Absorption
<br />
<br />. , Accuracy 'and precisiollwere estimated 'On' the 'larger muscle
<br />tissue (-20 g) samples by the preparation and -analysis of NIST
<br />
<br /> .' -, ".B;;WaddellandT:' S. May
<br />Table 2. ConcentIatioosofselenium,in fish muscle plugs Collected
<br />from the mid-dorsal area of live razorback suckers. ReSults expressed
<br />as fJ.g1g dry weight ":'"
<br />Collection :. (.rim)"
<br />iocation ~Len~ Sex Se Se"
<br /> C
<br />Stewart Lake Outlet ".481<'" ",1,231 M 23.9
<br />Escalante 'Bar 573": 1,849 F 3.75
<br />Escalante Bar:;;c;'i 523j. . 1,551 F 3:82:
<br />AshleyoCreek;' . 511.'''''.;; 1;373 ?" 11:9;:";
<br />Ashley Creek '502: 1,304 '/ 38,7
<br />Ashley Creek j 480.; 1,'236 M 13.1
<br />Ashley Creek 477 :L'i' 1,390 -1 43.6
<br />; Ashley Creek 475 1 ,390T' 1 .....39.7 )
<br />Ashley Creek 583 1,853' 1 33,8
<br />. Ashley Creek 491 1,412 1 54.1 t
<br />Ashley Creek .' . 488 " 1,337 1 43.3
<br />Ashley Creek 510 1,517 1 18.6-
<br />Razorback;Bar '512' 1,543 M 4.05
<br />Razorback Bar 471 1,127 M n.5 <1.1
<br />Razorback Bar 526 1,570 M 3.55 2.8
<br />Razorback Bar 549 1,798 F 4.38 3.7
<br />Razorback Bar 540 1,649 F 7.14 4.7
<br />Razorback Bar 545 1,485 F 32.0 10.6
<br />Razorback Bar 504 1,375 M 4.51 1.3
<br />Razorback Bar 546 1,814 M 7.37 J.8
<br />RaZorback Bar 477 1,176 M 26.0 6.7
<br />Razorback Bar 549 1,798 F 4.38
<br />Razorback Bar 543 1,965 F 4.64
<br />Razorback 'Bar 485 1,088 1 6.45
<br />Old O1ar1ie Washb 5.63
<br />
<br />
<br />&Seconcentration (fJ.g1g dry weight) in eggs or milt (Hamilton and
<br />Waddell 1994)
<br />brazorback X tlannelmouth sucker hybrid
<br />. c sex not identified
<br />
<br />reference materials'~ duplicate samples, pre-digestionspikes,
<br />and procedural blanks: Results of these analyses are shown in
<br />Table lb. Procedural ~I~ were acceptable because the sele-
<br />nium concentration,,of ,the nearest f~h muscle sample was
<br />greater by an oroc.r,of magnitude difference (2.7 ppm). The
<br />relative percent difference (RPD) from three samples prepared
<br />and analyzed in duplicate was well within the maximum aUow-
<br />able 10 RPD. Recoveries from the preparation and analysis of
<br />NIST reference'btaterials1566a (oyster tissue) and 1577a (bo-
<br />vine liver) were close to certified ranges for selenium. The
<br />results from.P're~~~~stion spikes were. well with.in the. accept-
<br />able percent recoveries of 8Q-120. Theniethod limit of detec-
<br />tion was O.2Jiglg~l*~ium. .
<br />
<br />;-; - - ~(,
<br />
<br />Selenium Residues'.in .Razorback Suckers
<br />
<br />';:!L
<br />
<br />
<br />COricbnb:ationSof 'selemllm' inlyophilize'd muscle plugs taken
<br />fromthe'iiiid-4ofsal ;areaoflive.razorbacksuckerS8re shown in
<br />Table' 2: Selenium <;bndintrations in mUscle plugs were vari-
<br />able, ranging' from 3.55 to 54.1 J.Lglg. All fish (eight) collected
<br />from Ashley Creek and three from Razorback Bar exceeded 8
<br />J.Lglg selenium dry weight. Selenium concentrations in fish
<br />skeletal muscle equal to or exceedingS'J.Lglg dry weight have
<br />been implicated in reproductive failure (Lemly and Smith
<br />1987). Although weights of muscle plugs collected from live
<br />razorbacks varied widely (5.6 to 30.3 mg), there was no signif-
<br />
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