Annual variation of dissolved free primary amines in estuarine water and sediment.

The concentration of dissolved free primary amines (DFPA), determined as fluorescamine positive material, was quantified during a one year period of a small estuary. In the water, the concentration of DFPA ranged from 1.8 μM in winter, to 26.5 μM in summer. In the sediment, from 16 to 56 μM of DFPA occurred. The concentration varied with depth and season, and in summer months a maximum of DFPA was observed in the redox discontinuity layer. The DFPA peak in water and sediment coincided with maximum of the macrophytal biomass. About 80% of the fluorescamine positive material was identified as amino acids. Origin and distribution of primary amines in the estuarine environment are discussed.