Sethoxydim Risk Assessment

Appendix 3: Toxicity of Poast to fish, aquatic invertebrates, and aquatic plants. 
Animal 
Exposure 
Response 
Reference 
Bluegill sunfish 
(Lepomis 
macrochirus) 
Bluegill sunfish 
(Lepomis 
macrochirus) 
Sheepshead minnow 
(Cyprinodon 
variegatus), <24 
hours old 
Sheepshead minnow 
(Cyprinodon 
variegatus) 
2.2 ppm BAS 562 H under 
flow-through conditions for 
28 days; depuration period 
of 14 days 
2.78 ±0.30 ppm (measured 
concentration) of 
14
C-labeled BAS 9052 
(
Poast 
2
, 19.3% a.i.) under 
flow-through conditions for 
30 days; depuration period 
of 14 days 
Mean measured 
concentrations of 0, 6.6, 13, 
25, 50 or 98 mg ai/L 
sethoxydim for 33 days 
0, 2.7, 4.5, 7.2, 10.8, or 18.0 
mg/L 
Poast
 for 96 hours 
under static unaerated 
conditions. [Note: No 
substantial concentration 
related effects on dissolved 
oxygen or pH.  Oxygen 
depletion with time in both 
exposed and control 
groups.] 
Low tendency of sethoxydim 
or its metabolites to 
concentrate in bluegill 
sunfish. 
BCF: 
whole body = 21 (elimination 
half-life = 3.6 days) 
edible tissue = 7 (elimination 
half-life = 3.6 days) 
nonedible tissue = 25 
(elimination half-life = 3.6 
days) 
maximum BCF in whole fish 
= 6.98 and maximum residue 
level during uptake = 16.6 
ppm; 
maximum BCF in nonedible 
tissue = 7.66 and maximum 
residue concentration = 18.2 
ppm; 
maximum BCF in edible 
tissue = 2.87 and maximum 
residue concentration = 6.82 
ppm; 
NOEC = 98 mg ai/L 
LOEC >98 mg ai/L 
MATC >98 mg ai/L 
96-hour LC
50 
= 3.5 mg/L 
(95% CI = 2.7-4.5 mg/L) 
NOEC (survival) = 2.7 mg/L 
(estimated) 
2.7-18.0 mg/L caused loss of 
equilibrium and surfacing 
during the test. 
McKenna and Patel 
1991 
MRID 42118001-A 
MRID 42118001-B 
Vilkas and Kuc 
1981a 
MRID 00100537 
Graves et al.  1995 
MRID 43614601 
Ward and Boeri 
1989a 
MRID 41510602 
Appendix 3-2 

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Appendix 3: Toxicity of Poast to fish, aquatic invertebrates, and aquatic plants. 
Animal 
Exposure 
Response 
Reference 
Sheepshead minnow 
(Cyprinodon 
variegatus) 
Channel catfish 
(Ictalurus punctatus), 
300 treated and 300 
untreated 
Mean measured 
concentrations of 0 or 145.8 
mg/L sethoxydim (BAS 
9052 H; 
Poast 
2
, 19.3% a.i.) 
under static unaerated 
conditions for 96 hours 
0.084±0.001 
14
C-labeled 
BAS 9052 (
Poast 
2
, 19.3% 
a.i.) under static conditions 
for 34 days; depuration 
period of 14 days 
water concentration was 
achieved by applying 
14
C-labeled BAS 9052 to 
sandy loam soil at a 
surface application rate of 
0.5 lb ai/acre. 
96-hour LC
50 
>145.8 mg/L 
No sublethal effects were 
observed. 
maximum BCF during uptake 
were: 0.747 in whole fish, 
0.398 in edible tissues, and 
0.714 in nonedible tissues 
after 14-day depuration, 
14
C-residue concentrations in 
whole fish = 67.9% of 
maximum during uptake; 
14
C-residue concentrations in 
nonedible tissues =76% of 
maximum during uptake; 
residue concentration in 
edible tissues = 10% greater 
than the maximum during 
uptake. 
Ward and Boeri 
1992a 
MRID 42315101 
Vilkas and Kuc 
1981b 
MRID 00100538 
Appendix 3-3 

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Appendix 3: Toxicity of Poast to fish, aquatic invertebrates, and aquatic plants. 
Animal 
Exposure 
Response 
Reference 
Invertebrates 
Eastern oyster 
(Crassostrea 
virginica), embryos 
Eastern oyster 
(Crassostrea 
virginica), embryos 
and larvae 
Mysid shrimp 
(Mysidopsis bahia), 
<24 hours old 
Mysid shrimp 
(Mysidopsis bahia), 
11 days old 
Daphnia magna, 
neonates (<24 hours 
old) 
Daphnia magna 
Mean measured 
concentrations of 0 or 109 
mg/L sethoxydim tech for 
48 hours under static 
conditions 
Nominal concentrations of 
0.0-2.5 mg/L Poast for 96 
hours under static unaerated 
conditions 
0 or 141.8 mg/L sethoxydim 
(BAS 9052 H; 
Poast 
2
, 
19.3% a.i.) under static 
unaerated conditions for 96 
hours 
Nominal concentrations of 
0.0-3.0 mg/L Poast for 96 
hours under static unaerated 
conditions 
Nominal concentrations of 
0, 0.54, 1.1, 2.2, 4.3, or 8.6 
mg/L BAS 9052 06H (
Poast 
2
, 19.3% a.i.) for 48 hours 
under static conditions; 
(mean measured 
concentrations of 0, 0.57, 
1.1, 2.4, 4.6 or 8.9 mg/L) 
48-hour EC
50
 >109 mg/L 
NOEC = 109 mg/L 
48-hour EC
50 
= 0.9 mg/L 
(95% CI = 0.6-1.0 mg/L) 
96-hour LC
50 
>141.8 mg/L 
No sublethal effects were  
observed  
96-hour LC
50 
= 0.8 mg/L  
(95% CI = 0.7-1.1 mg/L)  
No sublethal effects were  
observerd.  
48-hour EC
50 
= 2.6 mg/L  
(95% CI = 2.0-3.3 mg/L)  
NOEC = 1.1 mg/L  
48-hour LC
50 
= 78.1 mg/L 
Linott 1992 
MRID 42537401 
Ward amd Boeri 
1990 
MRID 41607207 
Ward and Boeri 
1992b 
MRID 42315102 
Ward and Boeri 
1989b 
MRID 41510604 
Blasberg et al.  1991 
MRID 41885903 
BASF 1982 
1 
MRID 00100536 
Appendix 3-4 

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