Toxicity of CU, NI and Alkylbenzene Sulfonate (LAS) on the naturally occurring bacteria in the Rhône river plume

The toxicity of Cu++, Ni++, and linear alkylbenzene sulfonate to the bacterioplankton in the Rhóne River plume (Mediterranean Sea) was assessed by [3H]thymidine incorporation into trichloroacetic acid-insoluble material. This method proved useful to evaluate the toxic effect of three common pollutants to the natural bacterial population in a system with permanent mixtures of fresh and sea water. An important variability in the toxicity has been detected irrespective of bacterial density or activity. The variations in toxicity were associated with the changes of salinity, particulate matter, and nutrients in the river plume.