Fast Screening of Recalled Tylenol® for Tribromoanisole and Related Adulterants

Significance of the Topic

Rapid identification of chemical adulterants in consumer products is crucial for protecting public health and guiding emergency recall decisions. The detection of off-odor contaminants such as 2,4,6-tribromoanisole (TBA) in recalled Tylenol® underscores the need for streamlined analytical workflows that can handle high sample volumes under tight timelines.

Study Objectives and Overview

This study evaluates a combined QuEChERS (Quick, Easy, Cheap, Effective, Rugged, Safe) extraction approach and full mass-range GC-TOFMS analysis for fast screening of TBA, related anisoles, and bromophenols in ground Tylenol® caplets. Key aims include assessing extraction recoveries, comparing dispersive SPE cleanup formats, and demonstrating automated spectral deconvolution for impurity identification.

Methodology and Sample Preparation

• Sample fortification: Ground Tylenol® powder was wetted, spiked at nominal levels of 1,000 and 100 ng/g active ingredient using anisole and acid surrogate standards, then equilibrated.
• QuEChERS extraction: EN 15662 salts (MgSO4, NaCl, citrate) and 10 mL acetonitrile solvent were added, shaken, and centrifuged at 3,000 g.
• Cleanup comparison: Four dSPE tube formats (Q210, Q251, Q252, custom) containing mixtures of MgSO4, PSA, C18, and graphitized carbon black were evaluated alongside no-cleanup extracts.

Used Instrumentation

• LECO Pegasus III GC-TOFMS system with Rxi-5Sil MS (30 m×0.25 mm×0.25 µm) column, helium carrier, splitless injection.
• Q-sep™ 3000 centrifuge for sample partitioning and dispersive cleanup.

Main Results and Discussion

• Recoveries for TBA and related adulterants ranged from 51% to 82%, with modest variation across cleanup formats at the 1,000 ng/g level.
• High acetaminophen load limited dSPE effectiveness and risked analyte loss; eliminating cleanup did not significantly alter recoveries.
• Automated peak finding and spectral deconvolution successfully identified pentachloroanisole beneath a dominant acetaminophen peak, demonstrating robustness for trace screening in complex matrices.

Benefits and Practical Applications

• High throughput: Up to 24 extracts ready for analysis within 60 minutes.
• Broad analyte scope: Acetonitrile-based QuEChERS captures diverse chemical classes.
• Definitive identification: Full mass-range TOFMS and deconvolution distinguish targets from overwhelming matrix signals.
• Adaptability: Method extends to other consumer goods, raw materials, and environmental samples.

Future Trends and Potential Applications

• Integration of two-dimensional GC×GC-TOFMS for enhanced separation of coeluting peaks.
• Refinement of selective cleanup sorbents to minimize analyte loss in unknown screening scenarios.
• Application of high-resolution accurate mass spectrometry for improved non-targeted contaminant discovery.
• Automation and miniaturization of QuEChERS workflows for point-of-need testing.

Conclusion

The combined QuEChERS extraction and GC-TOFMS approach offers a rapid, cost-effective, and versatile platform for screening consumer products for trace adulterants. The method’s simplicity, speed, and ability to manage complex matrices make it well suited for emergency response and routine quality control.

Reference

1. P. Kavilanz, CNN.Money.com (2010).
2. R. Tracy, B. Skaalen, Practical Winery and Vineyard (2008).
3. F.B. Whitfield, J.L. Hill, K.J. Shaw, J. Agric. Food Chem. 45 (1997) 889.
4. EN 15662 (2008) Foods of Plant Origin—Determination of Pesticide Residues Using GC-MS/LC-MS/MS (QuEChERS).
5. P. Chatonnet et al., J. Agric. Food Chem. 52 (2004) 1255.