A comparison on five sediment decomposition procedures for determining anthropogenic trace metal pollution

Five different procedures of sediment decomposition were compared, for eval uating the one more appropriated for assessing anthropogenic metal pollutio n. Exchangeable-metal extraction in sodium acetate, weak extraction in hydr oxylamine hydrochloride/acetic acid, moderate extraction in diluted hydroch loric acid, oxidising strong acid digestion and total decomposition with hy drofluoric acid were tested. The mildest sodium acetate attack, which gives also better account for the bioavailable metal fraction, is the more effec tive in enhancing differences between polluted sediments and nonpolluted on es. Copper, lead and zinc are the best indicators of trace metal pollution of surface sediments.