Ecotoxicological characterization of liquid wastes from medical laboratories
The blood and urine samples taken in local medical laboratories are today treated in large analytical centres that enable the optimization of analyses, technically and economically. These centres are equipped with automatic machines that use various chemical reactants. These reactants sometimes contain very toxic substances, which can be released into urban sewage networks without treatment. In order to characterize the environmental hazard linked to these unknown liquid wastes, a chemical and ecotoxicological program was set up to investigate the liquid wastes of a pilot laboratory situated in the Lyon area. This program has demonstrated the strong ecotoxicity of liquid wastes from certain automatic analysis machines. It has also revealed the ecotoxicity of liquid wastes that are treated with bleach before release into the sewage network, in order to eliminate pathogenic germs. These results can be used by managers of analytical centres in order to improve the management of their liquid wastes: replacement of some reactants by less ecotoxic compounds, in situ pretreatment of certain liquid wastes, elimination of the most toxic liquid wastes in specialized treatment plants.