Environmental persistence, bioaccumulation, and hazards of chemicals in e-cigarette e-liquids: short-listing chemicals for risk assessments.

BACKGROUND/METHODS: Increased use and sales of e-cigarettes raises concerns about the potential environmental impacts throughout their life-cycle. However, few available research studies focus on the environmental impacts and ecotoxicity of e-cigarettes. In this study, we short-list e-liquid chemicals from published literature that should be considered in future environmental impact and risk assessments. We used a combination of available laboratory bioassays-based data and predictive methods (eg, Structure-Activity Relationships) to characterise the hazards of the e-liquid chemicals (environmental persistence, bioaccumulation, and aquatic toxicity including hazardous concentration values (concentration affecting specific proportion of species)) for short-listing. RESULTS: Of the 421 unique e-liquid chemicals compiled from literature, 35 are US Environmental Protection Agency's hazardous constituents, 42 are US Food and Drug Administration's harmful or potentially harmful constituents in tobacco products and smoke, and 20 are listed as both. Per hazard characteristics, we short-listed 81 chemicals that should be considered for future environmental impact and risk assessments, including tobacco-specific compounds (eg, nicotine, N'-nitrosonornicotine), polycyclic aromatic hydrocarbons (eg, chrysene), flavours (eg, (-)caryophyllene oxide), metals (eg, lead), phthalates (eg, di(2-ethylhexyl)phthalate) and flame retardants (eg, tris(4-methylphenyl)phosphate). IMPLICATIONS: Our findings documenting various hazardous chemicals in the e-liquids underscore the importance of awareness and education when handling or disposing of e-liquids/e-cigarettes and aim to inform strategies to prevent and reduce hazards from e-cigarettes. This includes any scenario where e-liquids can come into contact with people or the environment during e-liquid storage, manufacturing, use, and disposal practices. Overall, our study characterises the environmental hazards of e-liquid chemicals and provides regulators and researchers a readily available list for future ecological and health risk assessments.

Review of Use Prevalence, Susceptibility, Advertisement Exposure, and Access to Electronic Nicotine Delivery Systems among Minorities and Low-Income Populations in the United States.

Increased use of electronic nicotine delivery systems (ENDS) and improper disposal after use pose a public health and an environmental justice (EJ) concern if use prevalence is disproportionately high among minorities and people of low socioeconomic status (SES) (broadly termed "EJ populations" for the purposes of this review). This review synthesizes literature on demographic patterns of use prevalence, susceptibility, advertisement exposure, and access to ENDS, and extrapolates environmental tobacco exposure (ETE) from ENDS among EJ populations. Seven electronic databases were searched using ENDS-related terms. We included studies published between 2017 and May 2020 that described ENDS use prevalence, susceptibility to ENDS use, advertisement exposure, and access to ENDS by race, ethnicity, or SES. Data synthesis was based on the assumptions that ETE increases with high use prevalence, susceptibility may influence future use, and advertisement exposure and access may impact demographic differences in use. We identified 32 studies describing use prevalence, susceptibility, advertisement exposure, or access to vape shops and other tobacco retail outlets by race/ethnicity or SES. We found higher prevalence of ENDS use among non-Hispanic Whites and inconclusive use patterns by SES. Patterns of susceptibility to use, advertisement exposure, and access were also mixed, with slightly higher outcomes observed among low SES youth. However, the evidence base on advertisement exposure was limited, with limited generalizability. Our findings indicate low prevalence of ENDS use among EJ populations. While this suggests low potential ETE among these groups, mixed outcomes on susceptibility, advertisement exposure, and access to ENDS among low SES groups may affect future ENDS use and ETE. Educational campaigns that discourage ENDS uptake should target EJ youth. Initiatives aimed at managing vape shop presence in EJ communities and monitoring targeted advertisement are also needed.

Characterisation and potential migration of silver nanoparticles from commercially available polymeric food contact materials.

The potential for consumer exposure to nano-components in food contact materials (FCMs) is dependent on the migration of nanomaterials into food. Therefore, characterising the physico-chemical properties and potential for migration of constituents is an important step in assessing the safety of FCMs. A number of commercially available food storage products, purchased domestically within the United States and internationally, that claim to contain nanosilver were evaluated. The products were made of polyethylene, polypropylene and polyphenylene ether sulfone and all contained silver (0.001-36 mg kg(-1) of polymer). Silver migration was measured under various conditions, including using 3% acetic acid and water as food simulants. Low concentrations (sub-ppb levels) of silver were detected in the migration studies generally following a trend characterised by a surface desorption phenomenon, where the majority of the silver migration occurred in the first of three consecutive exposures. Silver nanoparticles were not detected in food simulants, suggesting that the silver migration may be due solely to ionic silver released into solution from oxidation of the silver nanoparticle surface. The absence of detectable silver nanoparticles was consistent with expectations from a physico-chemical view point. For the products tested, current USFDA guidance for evaluating migration from FCMs was applicable.