Ecological risk threshold for Pb in Chinese soils

Area of Science:

• Environmental Toxicology
• Ecotoxicology
• Risk Assessment

Background:

• Ecological risk thresholds for lead (Pb) are vital for soil protection policies but are under-researched.
• Limited data exists for deriving soil Pb ecological risk thresholds.

Purpose of the Study:

• To derive the ecological risk threshold for lead (Pb) in soil.
• To establish a prediction model for estimating Pb ecotoxicity thresholds based on soil properties.

Main Methods:

• Collected toxicological data for Pb from 30 endpoints.
• Applied species sensitivity distribution (SSD) method for interspecific extrapolation.
• Corrected toxicity data for leaching and aging before SSD curve fitting.

Main Results:

• Effective concentrations (EC10) ranged from 205.6 to 1596.3 mg kg⁻¹.
• Hormesis induced by Pb reached up to 118%.
• Developed a prediction model: LogHC5 = 0.134 pH + 0.315 LogOC + 0.324 LogCEC + 1.077.

Conclusions:

• The developed prediction model accurately estimates Pb ecotoxicity thresholds in various soils.
• This study provides a scientific framework for deriving Pb ecological risk thresholds.
• The findings are significant for ecological species protection.