Ecotoxicology / Biodegradability

Informations about Ecotoxicity and biodegradability, which are intrinsic properties of single chemicals or complex mixtures, are often required by law. For single chemicals for instance the European Chemicals Regulation REACH but also national legislation as the German Regulation on Substances Hazardous to Water (VwVwS) requests these informations. In the field of waste water disposal, whole effluent toxicity tests are the prerequisite of discharge permits for municipal and industrial treatment plants. The knowledge about the degradability of effluents which are to be treated in waste water treatment plants, is essential for their proper function.

Ecotoxicological Tests
The aim of ecotoxicological tests are to assess the potentially adverse effects of single chemicals ore mixtures of chemicals on biological organisms, especially at the population, community and ecosystem level. The basic principle of ecotoxicological testing is to determine the range of concentrations from the concentration level at which adverse effects on the population of test organisms start to be observable up to concentration with maximum effect. Effects could be the lethality of the organisms or an inhibition of growth or motility. Within this range, a concentration-effect-relation can be derived. By means of statistical models (Probit-Analysis), distinct toxicological endpoints such as the median effective concentration (EC50) can be calculated. In the field of effluent biotesting, the wastewater is examined in a dilution series following the geometric series of 2 and 3 (e.g. 2, 3, 4, 6, 8, 12 etc.) which are called “G-Levels” (dilution levels) according to the german standards (DIN).

Our ecotoxicological testing focuses on biological effects in aquatic environments, but tests with sediment organisms or even terrestric organisms can be offered, if required and announced far enough by the customer. All tests are in accordance with national or international standards (German Standard DIN, OECD Test Guidelines, ISO and others). Tests conducted at IDUS laboratory are listed in the left menu.

Tests for biodegradability
Biodegradabiliy means the property of a substance to be consumed by microorganisms and returned to compounds found in nature. Similar to ecotoxicity, biodegradability could be tested for distinct substances and also for complex mixtures (e.g. waste water). There are tests for the ready and the inherent biodegradability. Ready biodegradability is tested under aerobic conditions with only a small inokulum of non-preadapted microorganisms whereas inherent biodegradability is tested under conditions that favour even the degradation of poorly degradable substances (high biomass of possibly preadapted microorganisms). The different Tests offered by IDUS are listed in the left menu.