Dr Jean-Paul Schwitzguébel, Sylvie Aubert
COST Action 837
April 2000 – July 2003
Dr Peter Schroeder, GSF-Forschungszentrum für Umwelt und Gesundheit, Neuherberg, Germany, Dr Patricia Harvey, University of Greenwich, UK.
Sulphonated aromatics are important starting chemicals in the production and use of many dyes, pigments and detergents. Effluents from these industries, but also leachates from landfills, are thus often contaminated with sulphonated aromatics, giving to these chemicals an actual impact on the environment, especially fresh water. Removal of sulphonated aromatic compounds is a major challenge for dye and textile industry. Physico-chemical treatments have major disadvantages, including high cost, low efficiency and inapplicability to a wide variety of dyes. On the other hand, dyes and pigments are intentionally designed to be stable under typical usage conditions, and these chemicals are thus not uniformly susceptible to biodegradation in classical wastewater treatment plants.
The development of alternative treatments to eliminate these pollutants is a requirement. Constructed wetlands, hydroponic systems or nutrient-film techniques based on the use of appropriate green plants are able to remove a wide range of xenobiotics from wastewater. The project aimed to assess at small scale the feasibility of such a low cost, low maintenance phytotreatment for effluents loaded with sulphonated aromatic compounds.
Anthraquinone derivatives occur naturally in several plant species like rhubarb and these plants might possess enzymes able to metabolize sulphonated anthraquinones. Rhubarb, rumex and other plants have thus been grown under hydroponic conditions using artificial effluents. Five sulphonated anthraquinones have been chosen as model pollutants. These chemicals are efficiently taken up by rhubarb and other anthraquinone-producing species, and translocated to the shoot. The presence of metabolites, not yet identified, has also been observed, indicating the transformation of sulphonated anthraquinones. Since rhubarb is a hardy plant species, it may prove a promising candidate in developing a new efficient phytotreatment to decontaminate effluents from dye and textile industries.