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A new spectrophotometric method for the determination in aqueous solution of both organic and inorganic thiocyanates is described. Organic thiocyanates are determined by measuring at wavenumber of 2150 cm-1 the absorption of solutions directly extracted with carbon tetrachloride. Inorganic thiocyanates require a previous derivatization reaction with dimethylsulfate, and are determined as methylthiocyanates. The method is quick, accurate and selective. The results obtained suggest its utilization in analysis of aqueous samples.

The estuarine processes which can influence the release of nutrients of the River Tiber into the Tyrrhenian Sea have been studied. A conservative behaviour has been found for silicate in different hydrographic conditions.For nitrogen, positive increments in respect of the dilution values were found in summer, due to regeneration processes; on the contrary a conservative behaviour was observed when seawater did not intrude into the river.Dissolved phosphorus showed, in all the hydrographic conditions, a positive deviation in respect of the theoretical dilution values. This deviation has been attributed to regeneration processes which take place during the summer period. The chemical release of phosphate from particulate matter is predominant when the saline wedge is absent.

In Italy, two different types of wastes can be dumped in the seas: industrial wastes and dredged material. There are no cases of sludges from urban treatment plants being discharged into the sea.The sea dumping of harbour dredging sludges is a long standing practice, while the disposal of industrial wastes dates back to 1965.Two specific laws regulate these two activities, although they do not establish quality standards for the receiving sea environment. Careful evaluation must be made, case by case, of possible effects of discharge with regard to physico-chemical characteristics of materials, to general oceanological characteristics of the dumpsite and to the uses to which such a dumpsite is designated.The analysis of different cases of industrial waste dumping, carried out at the pre-operational level and during discharge, revealed some potential for negative long-term effects on the sea environment. This, as well as the increasing public sensitivity to environmental problems, led the management agencies in Italy to take several measures aimed to stop all forms of sea dumping of industrial wastes and to revise the general criteria in issuing permits for the discharge of dredged material.