Analysis of Heavy Metals in Cosmetics by ICP-MS - ISO 21392 -

Significance of the Topic

Heavy metal contamination in cosmetic products poses potential health risks due to direct skin contact and absorption. Regulatory bodies such as the International Cooperation on Cosmetics Regulation (ICCR) have set strict limits for lead and mercury in cosmetics, and the adoption of ISO 21392 ensures standardized analytical procedures for consumer safety.

Aims and Overview of the Study

This study applies the Shimadzu ICPMS-2040/2050 system to determine trace levels of eight heavy metals (Cr, Co, Ni, As, Cd, Sb, Pb, Hg) in lipstick, foundation, and eyeshadow, following ISO 21392 guidelines. The goal is to assess method performance, sensitivity, and cost efficiency.

Methodology

Sample pretreatment was based on ISO 21392 and involved:

• Weighing ~200 mg of cosmetic sample into a quartz insert.
• Adding 4 mL HNO₃, 0.5 mL HCl, 4 mL pure water, H₂O₂; microwave digestion at 200 °C for 30 min.
• Diluting to 50 mL, filtering through a 0.45 µm membrane, then a further 4× dilution (total factor 1000).
• Using Rh and Ir internal standards added online at a 9:1 sample-to-standard ratio.

Used Instrumentation

• Shimadzu ICPMS-2040/2050 with mini-torch (≈66 % argon gas reduction).
• AS-20 autosampler and Nebulizer DC04 with a cyclone spray chamber.
• Nickel sampling and skimmer cones.
• Helium cell gas for interference removal.
• Online internal standard introduction kit.

Main Results and Discussion

• Calibration standards from 0.5 to 30 µg/L yielded linear responses and limits of quantification well below ICCR limits (Pb: 10 mg/kg; Hg: 1 mg/kg).
• Measured concentrations in all cosmetic samples were under regulatory thresholds.
• Spike recovery tests (5 µg/L addition) returned 91–103 %, demonstrating accuracy.
• The mini-torch reduced argon consumption and operating costs without compromising sensitivity.

Benefits and Practical Applications

• Ensures rapid, reliable safety assessments of cosmetic products.
• Meets ISO 21392 and ICCR requirements for heavy metal monitoring.
• Reduces running costs via lower gas usage and streamlined sample introduction.

Future Trends and Potential Applications

Innovations expected in cosmetic analysis include:

• Greater automation of sample preparation and data handling.
• Expanded multi‐element and non‐targeted screening capabilities.
• Further miniaturization of plasma sources to lower resource consumption.

Conclusion

The Shimadzu ICPMS-2040/2050 platform, combined with ISO 21392 protocols, provides a robust, sensitive, and cost-effective solution for heavy metal analysis in cosmetics, supporting regulatory compliance and consumer safety.

References

1. ICCR-7 Traces Working Group (2013): Considerations on Acceptable Lead Levels in Cosmetic Products.
2. ICCR Joint Traces Working Group (2016): Recommendation for Acceptable Trace Mercury Levels in Cosmetic Products.
3. ISO 21392:2021: Cosmetics – Measurement of traces of heavy metals in cosmetic finished products using ICP-MS technique.