Disposable e-cigarette extracts from 8 national and regional
brands constituting 15 unique products were analyzed for heavy
metals by ICP-AES following TCLP and WET. Two of the twenty
three samples of the preliminary survey exceeded the TC limit for
lead. Replicate analysis of four disposable e-cigarettes found that
two products (5 samples) exceeded the TC limit and/or the STLC
for lead; these products represented the same brands as those
demonstrating higher lead leaching in the preliminary survey.
Thus, of the 15 products tested, two exceeded regulatory
thresholds. No samples exceeded TC limits or STLC for any other
metal. The results indicate that some e-cigarettes may be classified
as TC hazardous waste for lead leaching, though it is likely that a
majority will not. A large degree of variability was observed among
brands and products, suggesting that additional testing, if desired,
should be conducted on larger aggregated sample masses consisting
of multiple devices. The frequency of lead leaching greater than
hazardous waste thresholds was lower for the e-cigarettes tested
relative to other reported values for WEEE. However, the rate of
consumption and disposal of these products is assumed to be higher
than many other electronic products. There are no published data
regarding the amount of disposable e-cigarettes that are sold in the
US or internationally. Such data would be valuable to understand
the magnitude of this new waste stream and assist regulators
regarding management tactics.
Since discarded CCPs containing unused nicotine are regulated
as listed wastes under the US regulatory system, unused
e-cigarettes containing nicotine juice (and containers of the nicotine
juice itself) would be similarly regulated. This has implications
for retailers that sell disposable e-cigarettes as well as nicotine
juice for reusable e-cigarettes which are both widely sold in convenience
stores and malls across the country. The US EPA has previously
interpreted that unused patches, inhalers, or gum containing
nicotine intended for disposal would be considered hazardous
waste and subject to regulation. Discarded e-cigarettes that were
used for their intended purpose would not be listed wastes, but
may be regulated in a more stringent manner at the local level.
Guidance from both national and local regulators will help determine
the most appropriate waste management practices for
e-cigarettes.