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Table 10.01

Table 10.01: Toxicity of selenium to wildlife

Species

Life Stage

Data type

Chemical

Measured Parameters

Conc. in water (mg/L)

Conc. in diet (µg/g) dry wt

Effect

Reference

Anas platyrhynchos (mallards)

adult

F,M,1

selenite

-

3.500 (reduced from 5.000)

-

12-wk study, increased serum alanine amino-transferase (ALT) activity indicative of renal or hepatic dysfunction;

Fairbrother and Fowles, 1990
 

adult male

-

selenite

-

3.500

-

80-d study, significant reduction of body weight compared to control

  
 

adult

F,M,1

selenomethionine

-

2.200

-

12-wk study, signif. impaired delayed-type hypersensitive (DTH) response to tuberculin; signif. increased ALT ; increased plasma glutathione peroxidase (GPX)

  
 

hatch to six weeks

F,M,1

selenite

-

-

10.000

6-wk study, larger livers than controls

Heinz et al., 1988; Hoffman et al., 1989
 

hatch to six weeks

F,M,1

selenite

-

-

20.000

6-wk study, a decrease in food consumption and growth was seen

  
 

hatch to six weeks

F,M,1

selenite

-

-

40.000

6-wk study, resulted in 25% mortality; decrease in food consumption and growth; mortality may have been Se induced starvation

  
 

hatch to six weeks

F,M,1

selenite

-

-

80.000

6-wk study, resulted in 97.5% mortality; a decrease in food consumption and growth; mortality may have been Se induced starvation

  
 

hatch to six weeks

F,M,1

selenomethionine

-

-

20.000

6-wk study, a decrease in food consumption and growth was seen

  
 

hatch to six weeks

F,M,1

selenomethionine

-

-

40.000

6-wk study, resulted in 12.5% mortality; decrease in food consumption and growth; mortality may have been Se induced starvation

  
 

hatch to six weeks

F,M,1

selenomethionine

-

-

80.000

6-wk study, resulted in 100% mortality; a decrease in food consumption and growth; mortality may have been Se induced starvation

  

Anas platyrhynchos (mallards) (cont.)

hatch to six weeks

F,M,1

selenomethionine

-

-

10.000

6-wk study, elavated plasma and hepatic, reduced glutathione (GSH) peroxidase activity compared to control

Hoffman et al., 1989
 

hatch to six weeks

F,M,1

selenomethionine

-

-

20.000

6 wk study, elevated: plasma GSH peroxidase activity, hepatic protein; decreased, malondialdehyde: hepatic GSH peroxidase activity, GSH (49%) and hepatic thiol (SH) (23%)

  
 

hatch to six weeks

F,M,1

selenomethionine

-

-

40.000

6-wk study, decrease in plasma and hepatic GSH peroxidase activity, SH (45%), glutathione (78%); elevated plasma GSSG reductase, oxidised glutathione (93%), hepatic protein and malondialdehyde

  
 

hatch to six weeks

F,M,1

selenite

-

-

10.000

6-wk study, elevated plasma GSSG reductase, (GSH) (28%)

  
 

hatch to six weeks

F,M,1

selenite

-

-

20.000

6-wk study, oxidised glutathione (73%) decreased hepatic protein

  
 

hatch to six weeks

F,M,1

selenite

-

-

40.000

6-wk study, decrease in hepatic protein, SH ; elevated plasma GSSG reductase, GSH (39%), oxidised glutathione (93%), and malondialdehyde (32%)

  
 

adult-males

F,M,1

selenomethionine

-

-

10.000

8-d study, showed that Se could be detected in the food and will be avoided by the mallards during feeding; avoidance appeared to be caused by a conditioned response due to illness and not aversion to taste.

Heinz and Sanderson, 1990
 

adult-males

F,M,1

selenomethionine

-

-

20.000

8-d study, showed that Se could be detected in the food and will be avoided by the mallards during feeding; avoidance appeared to be caused by a conditioned response due to illness and not aversion to taste.

 

Anas platyrhynchos (mallards) (cont.)

adult-males

F,M,1

selenomethionine

-

-

15.000-100.000

17 wk study, (initial exposure of 15.000 ug/g for 21 wk pre-study period)12 weeks of control diet and then 5 weeks of 100.000; 14.7% mortality; 39.3% weight loss; Se in liver = 35 ug/g wet wt

Heinz, 1993
 

adult-males

F,M,1

selenomethionine

-

-

15.000-100.000

17 wk study, (no initial exposure)12 weeks of control diet and then 5 weeks of 100.000; 14.3% mortality; 41.2% weight loss; Se in liver = 40-53 ug/g wet wt; none of these were considered significant differences

  
 

female-adults and offspring

F,M,1

selenomethionine

-

-

8.000

long term study, females had 4.6 young that survived to six days compared to 8.1 in control; 6.8% malformations in young compared to 0.6 in control; reduced survival in ducklings whose parents were fed Se even though ducklings were fed control diet.

Heinz et al., 1989
 

female-adults and offspring

F,M,1

selenomethionine

-

-

16.000

long term study, females had no young that survived to six days compared to 8.1 in control; 67.9% malformations in young compared to 0.6 in control; reduced survival in ducklings whose parents were fed Se even though ducklings were fed control diet.

 
 

female-adults and offspring

F,M,1

selenocystine

-

-

16.000

No impairment to reproduction was seen.

  
 

adult-male

F,M,1

selenomethionine

-

-

20.000

16-wk study, mortality was 25%; body weights sinificantly decreased after 1 wk; 4 wks after being returned to untreated diet, weight of birds was close to control birds; mortality may have been enhanced by cold weather

Heinz and Fitzgerald, 1993 (a)

Anas platyrhynchos (mallards) (cont.)

adult-male

F,M,1

selenomethionine

-

-

40.000

16-wk study, mortality was 95% by 11 wks; body weights sinificantly decreased after 1 wk; 1 bird left at end of study died within 5 days after being returned to untreated diet; mortality may have been enhanced by cold weather

Heinz and Fitzgerald, 1993 (a) (cont.)

 

adult-male

F,M,1

selenomethionine

-

-

80.000

16-wk study, mortality was 100% by wk 8; body weights sinificantly decreased after 1 wk; mortality may have been enhanced by cold weather

  
 

adult-male

F,M,1

selenomethionine

-

-

15.000

5-mos. study, (Nov to April), 1 of 46 died

Heinz and Fitzgerald, 1993 (b)
 

adult-female

F,M,1

selenomethionine

-

-

15.000

5-mos. study, (Nov to April), 3 of 45 died

  
 

1 day old ducklings

F,M,1

selenomethionine

-

-

60.000

4-wk study, 22% protein in diets; duckling survival and growth was reduced (40% mortality) and livers had histopathological lesions.

Hoffman et al., 1992
 

1 day old ducklings

F,M,1

selenomethionine

-

-

60.000

4-wk study, 7% protein (isocaloric) in diets; 100% mortality

  
 

1 day old ducklings

F,M,1

selenomethionine + sodium arsenate

-

-

15.000 to 60.000 Se + 200.000 As

4-wk study, 22% protein in diets; complete or partial alleviation of following Se toxic effects: mortality, impaired growth, hepatic lesions, lipid peroxidation, altered glutathione and thiol status

  
 

1 day old ducklings

F,M,1

selenomethionine + sodium arsenate

-

-

15.000 to 60.000 Se + 200.000 As

4-wk study, 7% protein (isocaloric) in diets; 53-73% mortality; much less alleviation of Se toxic effects

  
 

2 yr old male

F,M,1

selenomethionine

-

-

16.000

14 wk study (in spring), lower hemoglobin; linear dose response to GSSG and ratio to GSH; mean hepatic GSH and malondialdehyde

Hoffman et al., 1991(b)
 

2 yr old male

F,M,1

selenomethionine

-

-

32.000

14-wk study (in spring), same as 16 plus-10% mortality; histopathological effects including bile duct hyperplasia and hemosiderin pigmentation of the liver and spleen; lower hematocrit; elevated plasma alkaline phosphatase activity

 

Anas platyrhynchos (mallards) (cont.)

1 day old ducklings

F,M,1

selenomethionine

-

-

60.000

4-wk study, 22% protein in diets; duckling survival and growth was reduced (53% mortality) and livers had histopathological lesions on 25% of ducklings.

Hoffman et al., 1991(a)
 

1 day old ducklings

F,M,1

selenomethionine

-

-

60.000

4-wk study, 7% protein (isocaloric) in diets; 100% mortality

  
 

1 day old ducklings

F,M,1

selenomethionine + boric acid

-

-

15.000 to 60.000 Se + 200.000 B

4-wk study, 22% protein in diets; (up to 60% mortality); interactive effects resulted in further reduction in growth, and increases in plasma glutathione reductase activity, hematocrit hemoglobin and plasma protein conc.

  
 

1 day old ducklings

F,M,1

selenomethionine + boric acid

-

-

15.000 Se + 200.000 B

4-wk study, 7% protein (isocaloric) in diets; 27% mortality; enhanced accumulation of Se in liver; more enhanced syptoms seen due to interactive effects

 
 

1 day old ducklings

F,M,1

selenomethionine + boric acid

-

-

60.000 Se + 200.000 B

4-wk study, 7% protein (isocaloric) in diets; 100% mortality

 
 

adults and offspring

F,M,1

selenomethionine

-

-

10.000 fresh wt (diet contained about 10% moisture)

reproductive study, mainly teratogenic effects, reduced productivity and duckling survival; conc in eggs ranged from 2.9 to 5.6 ug/g wet wt and conc ranges in adult male and female livers were 6.1 to 12.0 and 2.6 to 6.2 respectively

Heinz et al., 1987
 

adults and offspring

F,M,1

selenite

-

-

10.000

mainly embryotoxic effects

  
 

adults and offspring

F,M,1

selenite

-

-

25.000

mainly embryotoxic effects, 1 male died after 57 days, significant reduction in weight of adults, females took longer to begin laying eggs and between laying intervals, reduced mean number of 21 day ducklings produced per female

  
 

adults

F,M,1

selenite

-

-

100.000

11 of 12 died; none laid eggs before they died

  
 

adults and offspring

F,M,1

selenite

-

-

10.000

6-wk prior to reproduction, 3.6 % malformations

Hoffman and Heinz, 1988

Anas platyrhynchos (mallards) (cont.)

adults and offspring

F,M,1

selenite

-

-

25.000

6-wk prior to reproduction, 4.2% malformations; decrease: by 40-44% in total number eggs hatched, by 19% in embryonic wt at 18 d of incubation, by 6% in crown length; fourfold elevation in plasma uric acid conc. indicative of renal alteration

Hoffman and Heinz, 1988 (cont.)
 

adults and offspring

F,M,1

selenomethionine

-

-

10.000

6-wk prior to reproduction, 13.1% malformations (often multiple); decrease: by 40-44% in total number eggs hatched; by 40% in plasma glutathione peroxidase activity, by 70% in sorbitol dehydrogenase activity

  
 

adults and offspring

F,M,1

selenomethionine

-

-

4.000

6 wk prior to reproduction, 1.4% malformation (compared to 0.5% at half this conc.) (including hydrocephaly, micropthalmia, lower bill defects and foot defects with ectrodactyly

  
 

adults and offspring

F,M,1

selenomethionine

-

-

8.000

6 wk prior to reproduction,6.8% malformation (compared to 0.5% at half this conc.) (including hydrocephaly, micropthalmia, lower bill defects and foot defects with ectrodactyly); decreased hatching by 36%

  
 

adults and offspring

F,M,1

selenomethionine

-

-

16.000

6 wk prior to reproduction, 67.9% malformation (compared to 0.5% at half this conc.) (including hydrocephaly, micropthalmia, lower bill defects and foot defects with ectrodactyly); decreased hatching by 91%

  
 

-

-

originates mostly form selenate in water and converts to organic form

-

0.300 in water entering Kesterson ponds

22.000-175.000 in plants, inverts., and fish from ponds

16.7% dead embryos in nest, 2.5% in eggs, 10.0% abnormal embryos or chicks in nest and 4.0 in eggs (eyes, legs/feet, beak and hydrocephaly)

  
 

-

-

-

-

* 0.0021

-

toxicity thresholds were devised for individual wildlife

Peterson and Nebeker, 1992

Ceryle alcyon (belted kingfisher)

-

-

-

-

* 0.0009

-

toxicity thresholds were devised for individual wildlife

Peterson and Nebeker, 1992

Cistothorus palustris (marsh wren)

-

-

-

-

* 0.0008

-

toxicity thresholds were devised for individual wildlife

Peterson and Nebeker, 1992

Fulica americana (American coot)

-

-

originates mostly form selenate in water and converts to organic form

-

0.300 in water entering Kesterson ponds

22.000-175.000 in plants, inverts., and fish from ponds

59.3% dead embryos in nest, 14.6% in eggs, 42.4% abnormal embryos or chicks in nest and 8.8 in eggs high mortality of hatchlings; no nests found in area in 1984-85 where 92 had been found in 1983; 94.4 and 96.6 µg Se/g in liver and kidney, respectively

Ohlendorf et al., 1986; Ohlendorf et al., 1988

Haliaeetus leucocephalus (bald eagle)

-

-

-

-

* 0.0019

-

toxicity thresholds were devised for individual wildlife

Peterson and Nebeker, 1992

Himantopus mexicanus (black-necked stilt)

-

-

originates mostly form selenate in water and converts to organic form

-

0.300 in water entering Kesterson ponds

22.000-175.000 in plants, inverts., and fish from ponds

16.7% dead embryos in nest, 5.8% in eggs, 17.6% abnormal embryos or chicks in nest and 6.8 in eggs (eyes, legs/feet, beak, hydrocephaly, exencephaly and wings)

Ohlendorf et al., 1986; Ohlendorf et al., 1988

Pandion haliaetus (osprey)

  

-

-

-

* 0.0013

-

toxicity thresholds were devised for individual wildlife

Peterson and Nebeker, 1992

Podilymbus podiceps (eared grebe)

-

-

originates mostly form selenate in water and converts to organic form

-

0.300 in water entering Kesterson ponds

22.000-175.000 in plants, inverts., and fish from ponds

60.0% dead embryos in nest, 31.7% in eggs, 15.7% abnormal embryos or chicks in nest and 5.5 in eggs (eyes, legs/feet, beak, hydrocephaly, exencephaly and wings); high mortality of hatchlings

Ohlendorf et al., 1986; Ohlendorf et al., 1988

Zalophus californianus (California sea lion)

adult

-

-

-

-

fish diet: 1.010 ¨g Se/g wet wt in minnows and mackerel,

100% mortality; gross lesions of stomach interpreted as necrosis; ulcers in stomach were chronic and consisted of mucosal necrosis and fibroplasia; small lesions in brain; nonsupperative encephalitus; lungs hyperemic

Edwards et al., 1989
 

adult

-

-

-

-

1.060 in sardines and 0.700 in smelts

100% mortality; gross lesions of stomach interpreted as necrosis; large lesions in brain; nonsupperative encephalitus; lungs hyperemic

  

Zalophus californianus (California sea lion) (cont.)

adult

-

-

-

-

-

100% mortality; moderate multifocal pulmonary emphysema and atelectasis, moderated adrenal exhaustion and mild focal myopathy; skeletal muscle had occasional degenerate myofibers with nuclear proliferation and regeneration; no significant lesions

Edwards et al., 1989 (cont.)
                 

KEY

                

LC = Lethal Concentration

1 = Primary

M = Measured

          

S = Static Test Method

2 = Secondary

N = Nominal

          

F = Flowthrough Test Method

              

 

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