Application of static headspace GC-MS for detection of residual trichloroethylene and toluene solvents in...

Trichloroethylene (TCE) and toluene (TOL), which have been used for β-cyclodextrin (β-CD) synthesis, need to be properly inspected for quality assurance and safety of food additives. In this study, a combination of static headspace separation and gas chromatography-mass spectrometry (SH-GC-MS) was optimized for detecting those residual solvents in β-CD in the compatible safe and green chemistry. Sample injection amount for SH was determined to 100 μL with the minimum volume that provides the suitable accuracy. For the safety and accuracy of analysis, equilibrium conditions of solvents were considered and selected to 60°C for 45 min. Also, we found that the addition of salt, like CaCl₂, adversely affected recovery efficiency. Under the proposed condition, coefficients of determination (R²) of both TCE and TOL were more than 0.99 between 0.05-10 mg/L concentrations. Recovery rates and relative standard deviation (RSD) of tested solvents were between 91.7-106.0% and 1.0-8.9%, respectively. From validation with two commercial β-CDs, both TCE and TOL presented lower than regulatory limits for food additives (1 ppm) with satisfactory RSDs (<20%). Collectively, the proposed analytical methods can contribute to safer, simpler, and greener inspection of residual chemicals present in foods for public health.