Fast Analysis of Arsenic Species in Wines using LC-ICP-QQQ

Significance of the Topic

Arsenic contamination in food and beverages poses significant health risks due to the varying toxicity of its chemical forms. In wines, inorganic arsenic species As(III) and As(V) are of particular concern as class 1 carcinogens. Regulatory bodies in Canada and Europe have established maximum limits for total arsenic, while the US lacks specific wine guidelines, highlighting the need for rapid and reliable speciation methods.

Objectives and Study Overview

This study aimed to develop and validate a fast, high-throughput method coupling liquid chromatography with triple quadrupole ICP-MS (LC-ICP-QQQ) for arsenic speciation in wine. Five wine styles were selected for method validation and an additional five for a commercial market survey, focusing on quantifying inorganic and key organic arsenic species within a single two-minute run time.

Methodology

Samples were oxidized with hydrogen peroxide to convert As(III) into As(V), simplifying inorganic arsenic determination. A small injection volume and narrow-bore ion exchange column enabled high mobile phase velocities. Detection limits and quantitation thresholds were established through repeated mixed-standard measurements.

Instrumentation Used

Agilent 1260 HPLC with Hamilton PRP-X100 column (50×2.1 mm, 5 μm) and Agilent 8800 Triple Quadrupole ICP-MS. Mobile phase: 40 mM ammonium carbonate with 3% methanol at pH 9.0. Oxygen reaction gas in the collision cell was employed to eliminate spectral interferences on m/z 75.

Main Results and Discussion

• Separation of arsenic species completed in under two minutes, achieving a 10-fold reduction in run time compared to FDA methods.
• Limits of detection (LOD) ranged from 0.018 to 0.026 μg/kg; limits of quantitation (LOQ) from 0.175 to 0.258 μg/kg. Accounting for sample dilution, wine LOQs were 1.1–1.5 μg/kg.
• Spike recoveries for DMA, MMA, and total inorganic arsenic averaged 100 ± 3 %, demonstrating method accuracy.
• Analysis of ten wines revealed inorganic arsenic as the predominant species, with concentrations from 1.7 to 32.9 μg/kg; one rosé sample contained DMA above the LOQ.
• Results agreed within ±10 % of those obtained by the FDA extended method (EAM §4.10).

Benefits and Practical Applications

The proposed method offers outstanding throughput and sensitivity for routine quality control and regulatory compliance in laboratories. Its rapid analysis time and robust quantification capability make it suitable for screening large wine sample sets and other food matrices.

Future Trends and Potential Applications

Further integration of automated sample preparation and on-line oxidation could enhance throughput. Expanding this approach to other beverages and foodstuffs will support broader arsenic monitoring programs. Advances in ICP-MS technology may enable simultaneous multi-element speciation assays.

Conclusion

A fast, fit-for-purpose LC-ICP-QQQ method enables reliable arsenic speciation in under two minutes per sample, with excellent sensitivity and agreement with established protocols. It meets current regulatory needs and supports proactive risk assessment in the wine industry.

References

1. Garelick H. et al. Rev Environ Contam Toxicol 2008;197:17–60.
2. FDA Guidance for Industry Arsenic in Apple Juice 2013.
3. Ontario VQA Wine Standards 1999.
4. OIV Compendium of International Methods of Analysis 2011.
5. Sadee B., Foulkes M.E., Hill S.J. J Anal At Spectrom 2015;30:102–118.
6. Jackson B.P. J Anal At Spectrom 2015;30:1405–1407.
7. Musil S. et al. Anal Chem 2014;86(2):993–999.
8. Hansen H.R. et al. J Environ Monit 2011;13:32–34.
9. Kubachka K.M. et al. FDA EAM §4.10 2017.
10. Tanabe C.K. et al. J Agric Food Chem 2017;65(20):4193–4199.