Analytical approaches for investigation of partially identified leachables in ENDS

E-cigarette liquids can change chemically while they are stored. At the same time, materials used in pods and disposable devices may also release chemicals into the liquid. This can make it difficult to determine where a newly detected chemical came from.

In this study, researchers investigated five partially identified chemicals found after unflavoured e-liquid had been stored in a JUUL2 pod for 12 months. Tests using artificially aged e-liquid and specially labelled ingredients indicated that four of the five chemicals came from nicotine and the fifth from benzoic acid.

When a chemical appears in stored e-liquid, it is important to know whether it came from the device materials or developed through chemical changes in the liquid itself.

Better analytical methods can help researchers assess electronic cigarette products more accurately. This study focused on identifying the source of chemicals and did not establish whether the identified compounds cause health effects in users.

Understanding what chemicals may be present in e-cigarette liquids and where they come from is relevant to product safety assessment.

The findings also show why detailed chemical testing is needed when evaluating electronic nicotine delivery systems.

Regulators may require manufacturers to investigate chemicals that could move from device materials into e-liquid and eventually into aerosol.

Methods that distinguish between chemicals released by device materials and chemicals formed naturally during storage can improve product assessment.