The TCLP and WET analysis show that some e-cigarette products
have the potential to exceed hazardous waste thresholds for
lead (though a majority of those tested did not); none of the other
hazardous metals surpassed their respective regulatory threshold.
Also noted was a wide variation between replicate analyses and
among the different products. When compared to other common
consumer electronics (Musson et al., 2006), e-cigarettes less frequently
were characterized as hazardous waste. The results do,
however, provide sufficient justification for regulatory agencies
to require testing prior to making such a determination. This study
was not intended to characterize any individual brand or product,
rather to provide data to assess whether exceeding such thresholds
was a possibility. If more detailed product testing were performed,
testing on larger batches consisting of multiple devices is warranted.
Potential hazardous waste characterization because of lead
leaching would apply to both used and unused e-cigarettes. The
nicotine solution in unused e-cigarettes would trigger characterization
as a listed hazardous waste.