Multifractal analysis for estimating heavy metal thresholds in Shantou, Guangdong

Area of Science:

• Environmental Science
• Geochemistry
• Risk Assessment

Background:

• Standard threshold values are crucial for environmental assessments, but some heavy metals lack national standards.
• Existing methods using background values or omitting elements have scientific limitations in pollution assessment.
• There's a need for accurate methods to assess soil pollution by elements lacking standardized risk values.

Purpose of the Study:

• To apply multifractal analysis for assessing soil heavy metal pollution in the Shantou area.
• To establish baseline values and risk assessment thresholds for 15 elements lacking national standards.
• To address the scientific shortcomings of traditional methods in heavy metal pollution assessment.

Main Methods:

• Multifractal analysis was employed to estimate pollution levels of 15 heavy metal elements (As, Cd, Cu, Zn, Cr, Pb, Ag, Be, Bi, Co, Mn, Sb, Sc, Ti, V).
• Baseline values and risk assessment thresholds were established for these elements.
• Spatial heterogeneity of heavy metals was analyzed, focusing on elements with non-normal distributions.

Main Results:

• Multifractal analysis effectively revealed the spatial heterogeneity of soil heavy metals.
• The method demonstrated significant advantages in assessment accuracy and scientific rigor over traditional approaches.
• Baseline values and risk assessment thresholds were successfully established for elements lacking national standards.

Conclusions:

• Multifractal analysis provides a scientifically rigorous approach for assessing soil heavy metal pollution, especially for elements without standard values.
• This study fills a critical gap in risk assessment for unstandardized heavy metals.
• The findings offer valuable technical support for regional soil pollution management and remediation strategies.