Environmental Fate

Environmental fate studies deal with the accumulation of chemical substances (bioaccumulation) in aquatic organisms and their mobility, transformation and metabolism in the environmental compartments like water and soil. Environmental Fate testing evaluates how a substance will react in the environment once in contact with water or soil. For determination of a precise mass balance of the resulting metabolites, the simulation tests can also be carried out using a radioactively labelled test substance.

InterBioTox can support the clients in a selected environmental fate tests under GLP in compliance with national and international guidelines. The studies are conducted either in the cluster or can be subcontracted in our established partners.

InterBioTox offers the following studies, which can help assessing the environmental fate of a substance: adsorption/desorption tests (test methods are useful for generating essential information on the mobility of chemicals and their distribution and behaviour in the soil, water and air compartments and the hydrolysis  (hydrolysis is an important factor and can influence the persistence of a substance in the environment and is particularly relevant for substances with low biodegradability).

For evaluating persistence in the context of a PBT/vPvB assessment under REACH currently either

screening tests for ready biodegradability (tests of the OECD 301 series) or simulation tests (OECD

307, 308, or 309) are applied. C14 radiolabelled simulation tests are carried out under environmentally relevant conditions (under aerobic and anaerobic conditions) directly in water sediment or soil system, and are highly comprehensive and results and interpretation depend on many variables.

The terms “bioconcentration” and “bioaccumulation” are both used in PBT assessment of the hazard and risk of chemical contamination in the environment and describes the enrichment of chemicals in organisms. Based on results of partition coefficient (Log K_ow), bioaccumulation studies are frequently requested by the authorities for highly lipophilic chemicals. The study evaluates the potential accumulation of the test compound in living organisms through an aqueous (standard and minimised tests) or dietary exposure under flow-through conditions (but semi-static regimes are permissible). Independent of the chosen exposure method, the bioconcentration fish test consists of two phases: exposure (uptake) and post-exposure (depuration). The aim of these studies is the determination of the biomagnification factor (BMF) or bioconcentration factor (BCF).