H. Hummel et al., EVALUATION OF FREE AMINO-ACIDS AS A BIOCHEMICAL INDICATOR OF METAL POLLUTION, Marine environmental research, 38(4), 1994, pp. 303-312
Mussels from the Fal estuary, STY England, were used to assess the app
licability of free amino acids as a biochemical stress-index for metal
pollution. Copper, and not salinity or zinc, was the main agent affec
ting the amounts and composition of the free amino acids. The use of t
he serine + threonine sum as an indicator of stress was highly questio
nable The taurine/glycine ratio could only be used at concentrations o
f copper greater than or equal to 20 mu g liter(-1), where the ratio w
as increased. At lower copper concentrations the taurine/glycine ratio
did not show a relationship with copper; at higher copper concentrati
ons the mussels died. The mussels seemed to show an 'all or nothing' e
ffect, i.e. the 'window' between tolerable and lethal levels for coppe
r was small.