Mercury levels in Lake Powell. Bioamplification of mercury in man-made desert reservoir

Flameless atomic absorption analyses of samples from Lake Powell yield mean mercury levels in ppb of 0.01 in water, 30 in bottom sediments, 10 in shoreline substrates, 34 in plant leaves, 145 in plant debris, 28 in algae, 10 in crayfish, and 232 in fish muscle. Trout were unique in having lower concentrations in muscle than in highly vascularized blood tissues. Concentrations increased with increased body weight and higher levels on the food chain. Muscle of some large fish over 2 kg whole body weight exceeded 500 ppb. Bioamplification of mercury up the food chain and association of mercury with organic matter are demonstrated.