Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Master → Israel → Genotoxic effect of discharged water from sea water desalination plant

Haïfa University (2014)

Genotoxic effect of discharged water from sea water desalination plant

Grossmark Yaara

Titre : Genotoxic effect of discharged water from sea water desalination plant

Auteur : Grossmark Yaara

Etablissement de soutenance : Haïfa University

Grade : Master 2014

Résumé partiel
Clean fresh water availability is one of the increasing limited resources worldwide. A useful and widely used solution for the shortage in drinking waters is sea water desalination, a practice that has been rapidly expanding in the last five decades and is predicted to exceed 38 billion m3 of water per year globally by 2016. There are several seawater desalination technologies, but the most commonly used is the reverse osmosis (RO) methodology. The RO method is the predominant method employed for water desalination in Israel. Since the mid 90’s, Israel has suffered from prolonged drought conditions, resulting in an acute water crisis. This crisis led the Israeli government to initiate a long-term and large-scale desalination program. At present there are four active desalination plants on the Mediterranean coast of Israel, all of which are SWRO (Sea Water Reverse Osmosis) based desalination plants : Hadera, Palmahim, Ashkelon and Sorek. An additional desalination plant employing the SWRO method is being constructed in Ashdod. In the RO method, seawater is forced at a pressure through a semi-permeable membrane. This membrane filters out salts, minerals and any other particulate and dissolved substances that are present in the seawater, including pollutants. Therefore the discharged water that goes back into the sea contains the concentrate substances present in the intake water and also a wide array of various additives which are an integral part of the desalting process. Conventional treatment compounds that are added to the intake water include : coagulations, pH adjustments, scale inhibitions and media filtrations. Residues of these materials are found in the discharge brine and have potentially various toxic impacts on the environment. Desalination plants may impact the surrounding environment and affect marine life around discharge outlets in several ways, including impacts associated with the hypersaline nature of discharge waters and the concentrated pollutants dissolved into them. But there are only a small number of published studies that provide actual measurements or results from laboratory experiments. Most published works focus on the effects and the extent of the high salinity plumes in receiving areas. The greatest threat to the receiving environment is the various potential toxicities of the materials present in the discharge waters. While some research on the effects of salinity and the quantitative measurements of heavy metals in discharge waters has been already done, there has been no research to evaluate defined toxicological parameters, such as the potential genotoxic load of the discharge brine. Genotoxicity is the scientific discipline describing the property of damages imposed by chemical agents on the genetic information within the cells. Genotoxic substances cause various damages to DNA. These damages may lead to cancer in the long term, to hereditary defects as a result of mutation in germ line cells and to teratogenic effects. Single- and double-DNA strand breaks were found to positively correlate with the presence and the level of genotoxic agents in the environment. For that purpose, the comet assay is a useful tool due to its ability to assess DNA damage, serving as a non-specific general biomarker for stress in many marine organisms. The purpose of this work is to evaluate the potential genotoxic, cytotoxic and whole organismal impacts of the discharge water emitted from desalination plants.

Présentation

Version intégrale (3 Mb)

Page publiée le 30 novembre 2018