Effects of aluminum on the biochemical composition of Atlantic salmon.

Biomolecule content, dry weight, and wet weight of Atlantic salmon, Salmo salar L., were monitored during 60-day exposure to aluminum, which began before hatch and extended to about the end of the alevin stage. The Atlantic salmon exposed to aluminum concentrations of 0, 33, 71, 124, or 264 micrograms/L at pH 5.5 for 60 days were evaluated for growth, survival, and biochemical effects on days 15, 30, and 60. Growth and survival were significantly reduced at the two highest aluminum concentrations by day 60. RNA and DNA were the most sensitive biomolecules monitored and were significantly reduced at the three highest aluminum concentrations by day 60. RNA:protein and RNA:DNA ratios were no more responsive than growth and survival. The lipid content of salmon was not significantly affected by exposure to aluminum. It was concluded that biomolecule content or ratios were not particularly sensitive indicators of growth effects in Atlantic salmon exposed to aluminum.