Oral nicotine pouches with an aftertaste? Part 2: in vitro toxicity in human gingival fibroblasts.

Introduction:
This article reports on a study investigating the in vitro toxicity of nicotine pouches in human gingival fibroblasts. The study aimed to identify potential health risks associated with nicotine pouches and to provide insights into the effects of the products on oral cells. The study was conducted in two parts, with part 2 focusing on the in vitro toxicity of five different nicotine pouches and a reference snus product.

Key Points:

* Nicotine pouches were extracted with a salt-buffered solution, and the cells were exposed to the extracts for 24 hours.
* Lactate dehydrogenase (LDh) and MTT assays were used to assess cytotoxicity, while the 2',7'-dichlorofluorescin diacetate (DCFDa) assay and quantitative real-time polymerase chain reaction (qRT-PCR) were used to measure oxidative stress and alterations in the gene expression of inflammatory and oxidative stress markers.
* Nicotine concentrations of sample extracts were quantified using a validated LC-DaD method.
* Flavorings and other substances identified in the tested pouches were discussed with regard to their potential contribution to toxicity.
* Cytotoxicity, inflammation, and oxidative stress responses were observed in the nicotine pouches, indicating that adverse effects such as local lesions in the buccal mucosa may occur after chronic product use.
* Flavorings used in nicotine pouches likely contribute to the toxicity of nicotine pouches.

Main Message:
The study found that nicotine pouches can cause cytotoxicity, inflammation, and oxidative stress responses in human gingival fibroblasts. The flavorings used in nicotine pouches likely contribute to their toxicity, indicating that adverse effects such as local lesions in the buccal mucosa may occur after chronic product use. The findings suggest that further research is needed to inform public health professionals and regulators on the risks possibly associated with the consumption of nicotine pouches.

Rinaldi, S., Pieper, E., Schulz, T., Zimmermann, R., Luch, a., Laux, P., & Mallock-Ohnesorg, N. (2023). Oral nicotine pouches with an aftertaste? Part 2: In vitro toxicity in human gingival fibroblasts. archives of Toxicology, 97(9), 2343–2356. https://doi.org/10.1007/s00204-023-03554-9