Analysis of e-cigarette warning letters issued by the Food and Drug Administration in 2020 and 2021.

Purpose: This study analyses the Food and Drug Administration (FDA) warning letters sent to e-cigarette companies from 1 January 2020 to 9 September 2021. Study results can inform regulation of e-cigarettes.

Methodology: Warning letters retrieved from FDA's website were coded for company type (retailer, manufacturer or distributor), location (domestic or international), infractions listed (PMTA (premarket tobacco product application), selling to minors, advertising to youth or packaging violation/mislabelling), product type (e-liquid, device or both), flavour (fruit, candy, tobacco, menthol/mint, concept flavour) and consequence (civil money penalties, product seizure and injunction, product detention and refusal of entry to the USA, no-tobacco-sales order, criminal prosecution).

Results: Of 303 coded letters (126 from 2020 and 177 from 2021), 97.4% were sent to small online retailers. Overall, 94.1% of the companies cited were located within the USA, 75.2% of the infractions were identified by reviewing a company's website and 70.5% were PMTA violations. In 2020, 55.6% of infractions were PMTA violations; in 2021, nearly all infractions were PMTA violations. The letters cited 880 products; 92.2% of which were e-liquid products, with 32.4% fruit and 31.1% concept flavours.

Discussion: Warning letters targeted small online retailers rather than large e-cigarette brands or products most used by youth: pod mods and disposables. The focus of these enforcement actions comprises a small share of the market and the impact on use was likely minimal. With PMTA decisions pending for the largest brands of e-cigarettes, the FDA should use its enforcement powers to target manufacturers, distributors and sellers of the tobacco products that have the greatest impact on youth and products that provide no public health benefit.