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De~'oresl, Brix, and Adams Debale/ Commelllary " lenl of 85% would result in an ovary concentralion of 46.4 mg/kg dw (Table 4). This concentralion differs from ours because Jarvinen and Ankley (1999) used the average ovary concerllration lhat resulled in mortality of 65 to 100% of the lalvae. Since an oval}' cOllcentralion of 38.6 mg/kg dw resullcd in SUbSlarlliallalval morlalily (65%), we did 1I0l wanl lo bias lhe average high by includillg ovary concentrations resulling in even greater mOrlality. Whole body concenlralions in lhe parelll bluegill were not measured in Ihis sludy, and lhe dieLary selenium conccnlratioll to which lhey were exposed is un- kllowlI since they were field collecled. Woock et al. (1987), Parcnt bluegill were fed a diet containing selcnomelhionine. In one trealment, !ish were also exposed to an aqueous concelllralioll of I 0 Jlg/L selenate. Afler 260 days, spawning experimellls were initiated. Artificial spawning beds were provided alld checked daily lor fcnil- ized eggs. Fenilized eggs were placed in embryo-larval cups aud assessed for percent hatch. lalval sUlvival, and abnormalities. Lalval slnvival from parcnl fish fed 13 mg/kg dw was significanlly (p < 0.(5) rednced, but not in lalvae from parenlS fed 3.6 mg/kg dw, resnlting in a chronic value of 6,1:1 mg/kg (I1v selenium. Lemly (I 993a) associated the dietary concerllration of 13 mg/kg dw wilh reproduclive failure. Selenium was nol measured in the ovaries or whole body tissue. USFWS (1990); Cleveland et al. {l993).Juvcnile blucgill were exposed to a waterborne 6;1 selcnate;selenite mixture for 60 days and to diclary seleno-J.- methionine for 90 days. In the waterborne exposure, mortality was signifi- cantly (p< 0.05) reduced in bluegill with whole body concenlrations of 5.0 mg/kg dw, but not in fish wilh 3,l:Img/kg dw selenium. This results in a chronic value of 4.4 mg/kg dw for Ihis endpoint (Tahle 3). In Ihe dielary experiment, an anomalous response in bluegill mortality aftcl' 90 days was obselved. Fish with a whole body concentration of 4.7 mg/kg dw had signifi- cantly (p < 0.05) elevated mOrlalily relative to lhe control fish. while mOHalily in fish with whole body concenlrations of approximately 7,5 to 13.5 was not . significanlly greater. Accordingly, the dietary test call not be used to calculate a chronic value. Lemly (1993a) similarly reported that a whole body concen- tration of5 mg/kg dw was associaled Wilh bluegill morLality (Table 3) ..J;uvinen and Ankley (1999) also reported thal the chronic value for increased monality in the walerborne selenium experiment was between 4 and 5.4 mg/kg dw. They also noled lhat mortality was not significantly grealer than controls in the dietary study up to a whole body residue of 13.5 mg/kg dw. lIermallutl. et al. (1992). Similar to lhe Schull:t and Hermanutz (1990) study described previously. adult bluegill were exposed to selenium in experimenlal streams dosed Wilh eilher 10 or 30 Jlg/L sclenite. U1uegillnesls were sampled lhrcc limes per week lor embryos and lalvae. Percentages of cleOId emhryos alld larvae were delermilled in Ihe laboratory. Randomly selectcd healthy emhryos were reared for several days in incuhalion cups cOlllaining the same slream W"dter and selenium concelllrations to which Ihey were exposed in Ihe ex peri- menial slreams. Halching percentage, Ialval smvival, and abnormalilies were recorded, AdullS were randomly collected from the experimental streams and analy:ted for selenium in their ovaries. Lalvae from females with an average ovary concentration of 30 mg/kg dw had a significant (p < 0.05) reduction in percent hatch and significantly greater mOrlality rates ill the first four days post-hatch (Table 4), It appears Lemly (199301) consclvatively related the obsclvcd clIccts in lalvae to the bluegill wilh lhe lowest individual ovary selenium conccntration (10 mg/kg dw) and considered this the concentra- tion resulting in reproductive failure. Howcver. live embryos were randomly selected from the cxperimenlal slrcams for embryo-Ialval sludies and there arc no data to suggest that all sampled embryos were spawned from the same female, Ict alone the female with the lowesl ovary selenium concenu'ation. Using ovary selenium dala from an imel'lnediale day of the lest,Jarvinen and Ankley (1999) similarly interpreted the resullS and rcportcd that an oval}' concentration of 29.3 mg/kg dw was associated with reduced survival. Assuming a percent moisturc of 75%. the averagc whole body selenium residuc in the parent /ish in the stream was 18 mg/kg dw (Table 3). Lemly (I 9!)3a) , in reporting a whole body concentration of 12 mg/kg dw, appears to have associated the lowest whole body rcsidue value with reproductive failure (Table 3), We helieve thc average residue is morc appropriate as discussed above. Based on their review..larvinen and Ankley (1999) report lhat a whole body residne of 11:1.4 mg/kg dw was associaled with reduced growth and sur- vival (Table 3), Coyle el ai, (1993). Bluegill sunfish were fed dielS containing selenium concentrations of 0,8, 4.6, 1:1,5, 16.8, and 33.3 mg/kg dw. and simultaneously exposed to an aqueous selenium concemration of 10 I-lg/L for 140 ~ays., Seleno-I.-nlelhionine was used for the dietary exposures and a 6:1 raUo 01 selenate:selenite was used for aqueous exposures. Spawning frequency, fccun- dity, and hatching snccess wcre monitored during thc last 1:10 days of the lest and fry slllvival was monitored for 30 days after hatch (fry were exposed to the same aqueous selenium concentrations as their parents ovcr the 30 day dura- tion), No clrecls on spawning frequency, fecundity, 01" hatching success were observed in any of the treatmcnts. However, larvae from females fcd thc 33,3 mg/kg dw diel had greatly reduced slllvival (7%) relative to olher treat- mcnts (75 to 90%) 5 to 6 days after hatching. Thcrefore, the dietary chronic valllc, is 23.7 mg/kg dw (Table 2). Lemly (1993a) determined from this study that a dielary concenlration of 16 mg/kg dw rcsulled in rcproductive failure. The hasis for this is unclear given that reproductive effects were not obselved in lish /Cd a dietary selenium concentration of 16.8 mg/kg dw. The mean ovary concentration in the parent fcmales of the affected lalvae was 35 109/kg dw, No signilicant clrecls on larval slllvival were obsclved in larvae from females with all ovary concenlration of 20 mg/kg dw, resulting in a chronic value lor the ovaries of 26 mg/kg dw (Table 4). Lemly (J 993a) associaled an OVill}' concelllration of 30 mg/kg dw reported in this sludy with repl'Odllctive lililure (Table 4). Jillvinen and Ankley (1999) reponed that an ovary concelltralion of 41.3lilg/kg ww was not associated with any elTeclS on I hllll, En)1. Risk Assess, Vol. 5, No.6, 1999 1207