Although this approach does not provide any definite evidence about a causal link between smoking and the disease, it can at least show whether there could be a causal relationship
He Z, Ma WY, Liu G, Zhang Y, Bode AM, Dong Z
[8] An electronic cigarette uses an e-liquid that may contain nicotine (typically derived from the tobacco plant), glycerin, propylene glycol, flavorings, and other ingredients
[sources 16] Amphetamine is known to strongly induce cocaine- and amphetamine-regulated transcript (CART) gene expression, [20] [216] a neuropeptide involved in feeding behavior, stress, and reward, which induces observable increases in neuronal development and survival in vitro
The long-term health implications of microplastic ingestion are not fully understood, but the World Health Organization flagged it as a legitimate area of concern as far back as 2019