Assessing soil cadmium quality standards for different land use types: A global synthesis

Area of Science:

• Environmental Science
• Soil Science
• Toxicology

Background:

• Cadmium (Cd) contamination in soil is a growing global concern, impacting human health, crop safety, and ecosystems.
• Standardized soil threshold values for regulating Cd exposure are currently lacking.
• Effective management of Cd-polluted soils requires comprehensive, globally synthesized data.

Purpose of the Study:

• To synthesize and analyze international soil environmental standards for cadmium (Cd).
• To categorize Cd standards by land use types globally.
• To recommend standardized soil Cd quality standards based on scientific models.

Main Methods:

• Synthesized soil environmental standards for Cd from 61 countries and 75 regions.
• Categorized standards based on land use types (agricultural, residential, industrial, etc.).
• Applied the ecological environment criteria - species sensitivity distribution (ECC-SSD) model with a log-logistic distribution.

Main Results:

• Soil Cd quality standards varied significantly across land use types globally.
• Ranges identified: 0.11-5.20 mg/kg (agricultural), 1.25-171.51 mg/kg (residential), 2.58-1845.26 mg/kg (industrial) within the 5-95% percentile.
• The 5% hazard concentration (HC5) was identified as a suitable benchmark for national quality standards.

Conclusions:

• The study provides a comprehensive assessment of global soil Cd quality standards.
• Findings offer valuable insights for policymakers in managing and mitigating Cd pollution.
• Recommends the HC5 value for establishing new national soil Cd quality standards across different land uses.