Sediment-Water Lumbriculus Toxicity Test Using Spiked Sediment (OECD TG 225)
The Sediment-Water Lumbriculus Toxicity Test using spiked sediment according to OECD TG 225 is designed to assess the effects of substances on sediment-dwelling aquatic oligochaetes, particularly Lumbriculus variegatus. This species is widely used as a representative benthic organism due to its ecological relevance and sensitivity to sediment-associated contaminants.
In this study, the test substance is directly incorporated into the sediment to create a defined exposure scenario. Lumbriculus variegatus individuals are then introduced and exposed under controlled laboratory conditions, typically over a period of 28 days.
Key endpoints include survival, biomass change, and reproduction, often assessed through the number of fragments produced as a result of asexual reproduction. These parameters are used to establish concentration–response relationships and to derive chronic toxicity endpoints such as the No Observed Effect Concentration (NOEC) and the Lowest Observed Effect Concentration (LOEC).
This test provides important information on the potential impact of chemicals on benthic organisms and sediment quality, contributing to a comprehensive environmental risk assessment of substances in aquatic environments.
