Behaviour of proteinaceous substances in the estuary of the Tama River

Abstract

Behaviour of dissolved and particulate proteinaceous substances in the estuary of the Tama River was investigated through field observations and laboratory experiments. Concentrations of dissolved proteinaceous substances in estuarine water were determined at eight stations between the mouth of the Tama River (TA-I5) and a point 16 km upstream (TA-8), using the colorimetric method of Lowry et al. (195i) that employs Folin phenol reagent. The results were expressed in terms of Folin phenol active substances (FPAS). It was found that FPAS decreased with increasing salinity and that the proportion of high molecular weight FPAS (molecular weight greater than 100,000) decreased rapidly in the estuary.The shapes, sizes and numbers of amorphous particulate substances stained by Amido Black 10B, called Amido Black active substances (ABAS), were determined under a microscope. The numbers of ABAS retained on Millipore HA filters (mean diameter: 10-80/1m) amounted to 450ml -~ in the estuarine water about 6km from the mouth of the estuary (Station TA-12M). Some of these aggregates are considered to be produced in situ by flocculation of high molecular weight FPAS during estuarine mixing. ABAS were also produced in experiments by mixing filtered river water with sea water.

Fluorescent Whitening Agents in Tokyo Bay and Adjacent Rivers: Their Application as Anthropogenic Molecular Markers in Coastal Environments

“…Estuaries act as filters of land-based chemicals to the ocean. It has been found that various land-derived materials are removed in estuaries through flocculation (39)(40)(41)(42), uptake by phytoplankton (43), and biodegradation (19). The application of FWAs as molecular markers in the marine environment requires their survival in estuaries.…”