Trends in e-cigarette exposures reported to an Australian poisons information centre between 2017 and 2023 with a reflection on legislative changes in 2021.

Background: Australians' use of e-cigarettes has increased dramatically in the last few years, following trends worldwide. The Australian Federal government introduced legislation on October 1st, 2021, which reclassified nicotine e-cigarettes as prescription only medicine in an attempt to curb their rapid uptake, especially amongst adolescents.

Methods: This is a retrospective analysis of e-cigarette exposure cases reported to the Victorian Poisons Information Centre between January 1st, 2017, and September 30th, 2023. The primary outcome was the trend in case number over the study period, analysed by breakpoint and interrupted time series analyses, as well as comparison of mean monthly calls in the 24 months before and after the introduction of the 2021 law. Secondary outcomes included shifts in route of exposure and severity pre- and post-legislation.

Results: There were 547 e-cigarette cases between January 2017 and September 2023. Most cases (n=454, 83%) were unintentional exposures, usually via inhalation (n = 271, 49.5%) or ingestion (n = 201, 36.8%). According to breakpoint analysis, the number of poisonings increased after March 2021 with rate ratio (RR) of 2.68 (95% CI 2.22, 3.68) and again increased after October 2021 (RR=1.66; 95% CI 1.43, 1.94). There were 103 e-cigarette exposure cases reported in the 24 months before the legislation was implemented in October 2021, and 358 in the following 24 months. The median monthly cases increased from 3 (IQR 2-4) to 15 (IQR 13-17), p < 0.001. The largest increase was seen in toddlers (1 to 4 years age group) whose median monthly exposures increased from 1 (IQR 0-2) to 9 (IQR 8-11), p < 0.001, but significant increases were also seen amongst infants, children and adults, p < 0.001 for all. Ingestion as the route of exposure decreased proportionally from 53% (55 cases) to 23% (84 cases). Conversely, inhalation increased from 21% (22 cases) to 68% (245 cases). Severity was unchanged, except in adolescents who saw an increase from a poisoning severity score of "none" to "minor".

Conclusion: The 2021 Australian federal legislation did not prevent increases in e-cigarette poisoning exposures in the context of their increased use, supporting the need for further regulation. Toddlers were identified as being particularly at-risk, suggesting educational campaigns for parents are warranted.