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The impact on the European sturgeon of toxic products and agricultural, domestic and industrial pollutants diffused in water, sediments and the food chain has hardly been studied. Nevertheless, different disruptions to the metabolism, the capacity and success in reproducing (maturity, fecundity, quality of gametes and viability of offspring), are attributed to these indirect threats in different species of fish and in certain other species of sturgeon:
- Dioxins (including PCB): metabolism of fats in the European eel
- Heavy metals (cadmium, mercury, etc.)
- Pesticides, herbicides, etc.
- Medicinal residues: antibiotics, antidepressants, oral contraceptives, etc. Also biologically active substances that are continually rejected into aquatic milieus. If all risks of acute toxicity are eliminated, these micropollutants are nevertheless likely to have an impact on aquatic organisms (metabolism, sex change, etc.)
It is therefore very probable that the rate of pollution, which is sometimes high in most basins where the sturgeon might be present, also affects its reproduction. Such a hypothesis has been suggested to explain the deterioration of the sperm quality (low spermatozoid mobility) observed in male reproducers accidentally caught in the Garonne and Dordogne. However the impact on the European sturgeon has not been studied and the extent of this degenerative phenomenon is unknown.
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Sturgeon 
