Dr Miriam León Paumen of the Institute for Biodiversity and Ecosystem Dynamics (IBED) discovered that exposing soil and sediment invertebrates like worms and springtails to toxic chemicals can give a more accurate test of soil contamination.

She also found that prolonged exposure can have a significant impact on the lifecycle of these invertebrates. Her findings give weight to the theory that gradual effects cannot be assumed in risk assessments for soil and sediment contamination.

Polycyclic Aromatic Compounds or PACs are a group of chemicals found in mineral oils and tars, among others, and are generated during the partial burning of fossil fuels and oil products. They constitute an important source of environmental pollution. In her research, Dr. Paumen exposed the invertebrates to PACs in lifecycle tests and found highly predictable effects on the species' development in 70% of the cases; specifically, she observed highly predictable arrested development. The findings show that soil and sediment contamination tests are more reliable when they are backed by the effects of prolonged exposure of soil and sediment fauna to toxic substances. The effects of PACs on terrestrial and benthic (species living at the bottom of a body of water) invertebrates is used to calculate the risks of soil and sediment contamination.

The research is part of the PhD project of Dr. Paumen, who received her doctorate on 13 February 2009. The results amongst others attracted the attention of the European Commission.