Preparation of fingernails for trace element analysis

Area of Science:

• Analytical Chemistry
• Trace Element Analysis
• Human Physiology

Background:

• Elemental composition of human nails shows significant variability.
• Standard washing procedures to remove contamination risk element extraction from the nail matrix.

Purpose of the Study:

• To investigate the impact of different washing solutions on human nail elemental composition.
• To determine if washing methods contribute to variability in reported nail element data.

Main Methods:

• Human nails were treated with nine different solvents previously used for nail cleaning.
• Residual elemental composition was measured using atomic absorption spectroscopy and energy dispersion analysis.

Main Results:

• Organic solvents caused less elemental loss compared to aqueous detergents.
• Aqueous acids resulted in the greatest elemental loss.
• Organic solvents extracted iron and magnesium more readily than calcium, copper, and zinc. Magnesium was almost entirely removed by distilled water or aqueous detergents.

Conclusions:

• The choice of washing solvent significantly affects the measured elemental composition of human nails.
• Variability in nail elemental analysis can be partly attributed to the washing procedures employed.
• Careful selection of non-extractive washing methods is crucial for accurate human nail elemental profiling.