Posted on 25 February 2015
In the past years several quantities of dead fish were found at the beaches near Scarlino. This created high attention also due to the large presence of tourists during the year.
Despite the numerous inspections made by ARPAT (EPA of Tuscany) it has never been possible to determine the main cause of this water pollution. The investigation didn’t take place continuously during the events and therefore the main substance or group of substances related to the death of the fish couldn’t be identified.
Therefore the authorities decided to acquire a system that monitors these events. The request for ARPAT to install a biological warning system was included in 2011 in the new Integrated Environmental Authorisation (AIA), issued to the companies by the authorities. The choice of the most suitable system had been left by the Minister of Environment and Land protection to the outcome of the debate between the companies and the local institutions (ARPAT, the town of Scarlino, the province of Grosseto), which are part of the technical committee.
In June 2013 the company Nuova Solmine selected Ecotox LDS’ From Cornaredo (MI) and the TOXcontrol biological monitoring system (microLAN the Netherlands), as part of a detailed survey on monitoring systems available on the market. Ecotox LDS has been a consulting company with regard to the methods of ecotoxicological investigation since 1992.
The TOXcontrol biological monitoring system is able to report toxic effects in the environment, even if it is due substances that are formed in the water sample for interactions or antagonism of molecules present, which are therefore not detectable by traditional chemical analysis.
The fundamental requirements for the system to apply into the canal of Solmine are identified in 3 prevailing characteristics:
- The utilization of an organism suitable for the environmental condition of the site of observation (seawater)
- The speed of response
- The interface with an appropriate data processing system, capable of generating an alarm sign.
An automatic system has been chosen (iTOXcontrol, microLAN-The Netherlands) which uses marine bacteria (Vibrio fischeri) which, in optimal living conditions, emits light.
If the quality of the water samples decreases due to the presence of eco-toxic products, the luminescence decreases in proportion to the concentration of the toxic substances. The light emissions are read by a photomultiplier and the data is processed according to the indication of the ISO 6341 – 3 Norm, providing an indication of the change in water quality of the sample.
The TOXcontrol is the only system in the world which can compare the influent (seawater) and effluent (cooling and waste water) in the same analysis run and thus give a quick reply in case there are toxic compounds which might go into the Mediterranean Sea.
This monitoring system has been the first, with this application, to be used in Italy, on a body receptor of seawater and required a significant engineering effort of Nuova Solmine that has taken on the management of the project. The suppliers of the equipment (microLAN BV and Ecotox) have assisted this with the installation of the instruments, the distribution of the samples of the system (Opus Automazione), and the integration of analytical data with the internal management system of Nuova Solmine, as well as sending an alarm signal to the control room (Eurotherm, Guanzata, MI).
The innovation of the system has attracted international interest and a delegation of the Korean government has visited the location, as the government is interested in including the use of toxicity systems in their legislation.