Conclusions
31
reproductive impairment in aquatic birds is to sample freshly laid eggs.
As with gravid fish ovaries, this single measure integrates dietary and
waterborne exposure and allows an evaluation based on the most sensitive biological endpoint.
Conclusions
Assessing selenium hazards to aquatic life is a two-step process. The
first step is to measure selenium concentrations in several environmental components and then interpret the potential toxicity of these
residues using biological effects guidelines. Key data and recommendations for toxic threshold values for selenium in water, sediments,
food-chain organisms, and fish and aquatic bird tissues (Table 2.4) have
been presented in this chapter. These values can be used as guidelines
TABLE 2.4. Toxic effect thresholds' for selenium in aquatic ecosystems. b
Selenium source
Water
Inorganic selenium
Organic selenium
Sediments
Food-chain organisms
Fish tissues
Whole-body
Skeletal muscle
(skinless fillets)
Liver
Ovary and eggs
Aquatic Birds
Liver
Eggs
Selenium
concentration'
2 Ilg/L
< 1 Ilg/L
2 llg/g
3 llg/g
7 llg/g
4 llg/g
8 llg/g
12 llg/g
10 llg/g
10 llg/g
7 llg/g
Effect
Food-chain bioaccumulation and
reproductive failure in fish and
aquatic birds
Food-chain bioaccumulation and
reproductive failure in fish and
aquatic birds
Food-chain bioaccumulation and
reproductive failure in fish and
aquatic birds
Reproductive failure in fish
Reproductive failure in aquatic birds
Mortality of juveniles and reproductive failure
Reproductive failure
Reproductive failure
Reproductive failure
Reproductive failure
Reproductive failure
• These are levels at which toxic effects begin to occur in sensitive species of fish and
aquatic birds. They are not levels that signify the point at which all species die from
selenium poisoning.
bRecommendation by author based on synthesis and interpretation of literature
cited in this chaper.
'Selenium concentrations in parts per billion for water; parts per million on a dry
weight basis for sediments, food-chain organisms, and fish and bird tissues.
31
reproductive impairment in aquatic birds is to sample freshly laid eggs.
As with gravid fish ovaries, this single measure integrates dietary and
waterborne exposure and allows an evaluation based on the most sensitive biological endpoint.
Conclusions
Assessing selenium hazards to aquatic life is a two-step process. The
first step is to measure selenium concentrations in several environmental components and then interpret the potential toxicity of these
residues using biological effects guidelines. Key data and recommendations for toxic threshold values for selenium in water, sediments,
food-chain organisms, and fish and aquatic bird tissues (Table 2.4) have
been presented in this chapter. These values can be used as guidelines
TABLE 2.4. Toxic effect thresholds' for selenium in aquatic ecosystems. b
Selenium source
Water
Inorganic selenium
Organic selenium
Sediments
Food-chain organisms
Fish tissues
Whole-body
Skeletal muscle
(skinless fillets)
Liver
Ovary and eggs
Aquatic Birds
Liver
Eggs
Selenium
concentration'
2 Ilg/L
< 1 Ilg/L
2 llg/g
3 llg/g
7 llg/g
4 llg/g
8 llg/g
12 llg/g
10 llg/g
10 llg/g
7 llg/g
Effect
Food-chain bioaccumulation and
reproductive failure in fish and
aquatic birds
Food-chain bioaccumulation and
reproductive failure in fish and
aquatic birds
Food-chain bioaccumulation and
reproductive failure in fish and
aquatic birds
Reproductive failure in fish
Reproductive failure in aquatic birds
Mortality of juveniles and reproductive failure
Reproductive failure
Reproductive failure
Reproductive failure
Reproductive failure
Reproductive failure
• These are levels at which toxic effects begin to occur in sensitive species of fish and
aquatic birds. They are not levels that signify the point at which all species die from
selenium poisoning.
bRecommendation by author based on synthesis and interpretation of literature
cited in this chaper.
'Selenium concentrations in parts per billion for water; parts per million on a dry
weight basis for sediments, food-chain organisms, and fish and bird tissues.