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DeForest, ".-ix, and Adams The NOEC and LOEC for survival OIL 60 days were 18.2 and 35.4 mg/kg dw, respeclively, resulling in a diel,lI)' chronic value of 25 IIlg/kg dw (Table 2). Based on growlh, the NOEC and LOEC OIL 60 days were 9,6 and 18,2 IIlg/ kg dw, resulLing in a dielal)' chrouic valne for lhis endpoinl of 13 mg/kg dw (Table 2). Use of the resulls after 60 days ralher lhan 90 days docs nol inlluence the chronic value (i,e., I he chronic value J(1I' growlh al (jO days is eqllivalentlo the chronic value for growlh and survival OIL 90 days). bUl il docs inlluence Ihe ECIO. EC~o' and ECsu values IhaL arc described laler in Ihe allalysis section. Lemly (199301) reponed frolll this sludy Ihal a dielal)' selelliulII concenLra- Lion of 5 mg/kg dw was associaLed wilh reduced growth. Howevel', growlh was reduced ollly atlhis concenLratioll in the experilllellt where salmon were fed rnosquiLofish fro III the San Luis Drain, As discnssed, due to pOleuLial cOIILami- ua.liO?;,lJyother.dl~lJlicals, tllese.rc.sl:II~~,are ~JUI c~nsidered a(>propriaLe. The ~:liig~~~~fto~icily;observe(rusiiigilisl;~li.2;'I;;~s~'7ih~,~is' Draill compared wi III' sele- 1~~W,~};~piked fisllfromthereferencesheleudsoLosuppon Ihe Il}'JJOlllesis LllaL other,contaminanls arc contribllling 10 effects. Using Ihe seleninlll.fonilied 1II0squilo1ish fmm Ihe reference sile, growlh, as discussed above, was only significantly (p < (l.05) reduced at dietary seleniulII concenlralious ~18,2 mg/kg dw. In the brackish waler sludy, salmon were less sensilive Ihan in fi'eshwaler. Following 90 days, the average whole body selenium concenlration iu fish with signilicant (P < 0.(5) lIIonalily was 10.8 IIIg/kg dw, while no effecls (p:> O.OS) on monalily were obselved in lish wilh a whole body residue of 5.4 mg/kg dw. This resulls ill a whole body chronic value of 7,(j mg/kg dw (Table 3). However, for reasons eXplained above, Ihe results afler 90 days are queslionable and probably less reliable Lhan Ihe results afler 6ll days. Based on the day 60 resulLs, the whole body NOEC and LOEC for survival were 10,4 and 23.4 mg/kg dw, respectively, resulting in a chronic value of 1 () mg/kg dw. For Lhe growth endpoint, the whole body NOEC and LOEC were 5.3 and 10.4 mg/kg dw, resulting in a chrouic value of 7.4 mg/kg dw, In conlrast, Lemly (1993a) reponed thai growth was reduced in /ish fed San Luis Drain mosquitofish and having a whole hody residue of 3 mg/kg dw (Table 3). Jalvinen and Ankley (1999) reporled the chronic vallie for sUlvival from Ihis study was 4 mg/kg dw (Table 3). Wannwater Fish Selenium residue sllldies on warmwaler 1ish are limited to fathead minnows (PimePhales promelas), bluegill sunfish (Lepomis macrochjrus), and std ped hass (Morolle sax(dilis). Sludies for each are described separalely below. Fathead Minnows (PirnePhales promelas) Bennett, Brooks, and Bo-raas (1986). The authors followed selenium lhrough a three-tiered food chain (algae-rotifer-fathead minnow larvae) in lhree labo- ratory experiments. In Ihe first experiment, 4-clay-old larvae were fed sele- I ! l Dcbatc/ ConIDlcntary nium-conlaminated rotifers lor 7 days, followed by a control diet for 19 days. JII the second experime11l, 8-day-old larvac were fed selenium-conlaminatcd mtilers for !) days. In experiment thrce, 2-day-old lalvae were fed selenium- contaminaled rolilers lor 7 days bclore test tenllinalion. Mean selenium concenlratious in rotifcrs fed to fathead miunow la!>'ae were :>70 and 68 mg/kg dw ill experimenls one and two, respectively, La!>'al growlh in bOlh of these experimenls was signilicautly (p< 0,05) reduced relative lo conlrol lish. The mean lalval selenium concenlraliou at the cnd of the 7-day exposure period was 43.0 mg/kg dw in experiment one, ami was 51.7 mg/kg dw in experimenltwo Crable 3). Larval growlh in experiment three was significantly reduced at a 90% conlidence level, but not at a 95% conlidence level. The mean lalval selenium concenLration was 61.1mg/kg dw. The mean selenium concelllration in n>tilers in experimcnL three was 55 mg/kg dw, Lemly (1993a) did 1I0t t:ite Illis stlldy ill his review. Similar to our review,.Jarvinen and Ankley ( 1 !J99) reponed that growth was reduced at a whole body concentration of 43 mg/kg dw, lJerlmlll (tjul llroollS (1986). Falhead minnows were exposed in the lahoratOl!, to either waterborne selenium, sclenium-cOllLaminilled food, or a combina- lion of Ihe two, Falhead minnows were exposed to waterborne selcnium, or the combinaLion of waterborne and dietal!, selenium, lor 8 weeks, Tests of fish exposed only to diet,lI)' selenium were terminated aflel' J 1 weeks. No effects on growlh were ohselved in falhead minnows fed a diet containing 7,3 mg/ kg dw selenium (and 43.5 flg/L selenium in the waler), the highest dielal!, concenlratioll lesled (Table 2), No clfects on growlh were obselved ill Ihe sludy in the highest whole body concenlrationmeasured, 2.2 mg/kg dw Crable 3), ,]<uvinen and Ankley (1999) reporl the same resulL for whole body tissue, Lemly (H)93a) did uol cite lhis sllldy in his I'eview, Ogle and Knight (1989). Tesling was initiated using approximately 6O-day-old fathead minnows. Fish were provided a diel spiked with 25% scleno-L-methion- ine, 25% sclenale, ami 50% selenite atmcasured concentrations of 5.2, 10,2, 15,2, :W,3, and :W,5 IIIg/kg dw. EvcI)' 2 weeks, /ish were collected and weighed. and olle !ish frolJ\ two or four rcplicates was removed for selenium analysis. Spawning sllhstralcs were provided on day 98. On day 105, a male and female were selecled and the spawning period was extended for 30 days afler the first spawning evelll in each replica Ie. Fish werc collecLed for selenium analysis at Ihe end of the spawning period. Eggs were collected and examined for fertility and iucubated for determinatiou of halchability. SUlvival of lalvallish arter 14 days was determined. Afler 98 days of exposure, growlh was significanlly reduced in !ish fed the diel conlaining 20.3 mg/kg dw selenium. The ecological signilicance of lhis level of growth reduclion (16%) is somewhal qlleslionable given Ihe variabililY in the responses at which signi1i- cant clreClS were ohserved (1.30 :t: 0,22 in lhe control and 1.09 :l: 0.16 in (ish /Cd 20.3 mg/kg dw selenium) and, lhallhe lish fed the highest selenium diel (29.5 mg/kg dw) had no signilicant (p:> 0.05) effecls on any reproduclive parameler evaluated: lIumber of spawns per pair, number of eggs per spawn, I hllll. Ecol. Risk Assess. Vol. 5. No, Ii. 1999 1203