From Contaminated Soil to Ecological Restoration: The Key Role of Bioremediation and Ecotoxicology

Contaminated soil represents a major hazardous waste stream in Europe, highlighting the need for sustainable treatment and management strategies. Bioremediation offers an effective approach for reducing organic contamination while preserving soil biological and agronomic functions, potentially enabling the reuse of treated soils in landscape restoration and natural engineering applications. However, chemical characterization alone may not adequately reflect the ecological quality of remediated soils, supporting the integration of ecotoxicological assessments within a risk-based evaluation framework. This study proposes a structured ecotoxicological workflow to assess the biological quality and reuse potential of soils following dynamic biopile bioremediation. The approach combines avoidance tests using the soil-dwelling organisms Eisenia fetida and Folsomia candida, with an optional reproduction test on Eisenia fetida to investigate potential chronic effects. The integration of ecotoxicological responses with soil characterization is intended to provide a comprehensive assessment of remediated soil quality, supporting hazard classification and informed decisions regarding its safe and sustainable reuse.