If a sample container is not filled to the recommended level, what could occur?

• A. It could reduce volatilization losses
• B. It could decrease contamination
• C. It could increase volatilization
• D. It has no effect

Answer: (C)

Volatilization is driven by the amount of air (headspace) above the liquid. When a container isn’t filled to the recommended level, there’s more headspace for volatile components to evaporate into. That extra evaporation increases volatilization losses, meaning more of the volatile analyte escapes before analysis and the measured amount can be lower or biased. So, the best outcome is that volatilization could increase. Filling to the proper level helps minimize these losses; underfilling doesn’t reduce them, and it doesn’t guarantee less contamination or no effect.