Substance or agent present in the soil (or groundwater) which, due to its properties, amount or concentration, causes adverse impacts on soil functions and negatively affects soil biota and other living beings.

Adapted from: CEN (2015) EN ISO 11074:2015 Soil Quality – Vocabulary. Available at:

And: Jones, R.J.A. et al. (2008) Environmental Assessment of Soil for Monitoring Volume V: Procedures & Protocols. Luxembourg. Available at:”