Evaluation of the detoxification efficiency of new technologies

Project co-ordinator: dr. Metka Filipič
Institute of Physical Biology

In order to achieve efficient control and reduction of the release of toxic and genotoxic substances into the environment, the set of chemical parameters used for evaluation of the efficiency of technologies for wastewater treatment and bioremediation of contaminated soil will be complemented with genotoxicity bioassays. These are an important integral tool in the development of efficient technologies for the treatment of specific wastes and waste waters, as well as for environmental monitoring. Aquatic organisms will be exposed to toxic substances, and changes in oxygen consumption will be measured using a twin-flow microrespirometer. Any significant variation from the normal (control) value might reflect an alternation in the metabolic demand of the organism or damage to the respiratory system. The metabolic potential of organisms will also be measured in order to provide additional information about the effects of substances on metabolism of organisms.

Genotoxicity will be evaluated using a combination of standard bacterial tests (the bacterial test for reverse mutations – Ames test (DIN 38412), or the test that detects DNA damage – SOS/umu test (DIN 38451; ISO/DIS 13829 (2000)), and the genotoxicity test with cells of human origin (human hepatoma cells HepG2) that will be modified for testing samples of effluents. Genotoxicity will be measured by measuring DNA damage with the comet assay (single cell electrophoresis), which is a new sensitive method for genotoxicity detection and quantification.

In parallel we will develop an in vitro test system based on genetically transformed mammalian cells, which will express a reporter gene (i.e. luciferase or green fluorescent protein which will be measured spectrophotometrically or luminometrically) as a response to DNA damage. The test will be simple to use and therefore useful for quick routine detection of genotoxicity and for monitoring of a large number of samples.