There is a significant increase in the use of electronic cigarettes (e-cigarettes) as an alternative to traditional smoking, but there is still some debate about their safety. The rise of e-cigarettes has changed the way people consume tobacco. While traditional smoking is a known risk factor for various cancers, vaping is thought to be a less harmful alternative due to the lack of combustion-related toxins. However, concerns about the safety of chemicals and flavorings in e- liquids have emerged. Research on the link between vaping and cancer risk is ongoing.¹

EVALI

E-cigarettes were introduced in 2007 as an alternative to cigarettes, but a cluster of causes related to lung injury was first reported in August 2019. This resulted in the EVALI condition. EVALI stands for e-cigarette or vaping use-associated lung injury. It is a term used to describe lung disease that can develop from vaping. EVALI causes inflammation in lung tissue, which has not been reported to affect patients with concurrent malignancy. EVALI is characterized by an acute inflammatory pulmonary process secondary to damage to the alveolar-capillary membrane, which causes the collapse of the alveoli and a serious alteration of gas exchange. (1) This inflammation is a response directly proportional to the exposure of the pulmonary endothelium both to the toxicity of the substances contained in the liquids of electronic cigarettes and to the frequency and time of exposure to them. There is an increasing prevalence of e- cigarette use globally, especially in Pakistan. Nicotine is the main addictive substance in tobacco, and tobacco combustion is responsible for most tobacco- related diseases.³

The prevalence of vaping has overtaken conventional cigarettes as the most frequent form of nicotine consumption among 15–24-year-olds.2 There are currently many both legitimate and illegitimate products and suppliers offering more than 8000 different flavors of vape on the market, whose additives are not tested, studied, or regulated and whose safety and toxicity profile remains unknown. In vitro, studies have demonstrated a dose-dependent decrease in the viability of normal human bronchial epithelial cells after exposure to vapor from electronic vape devices.⁴

Nicotine addiction:

E-cigarettes typically contain nicotine, an addictive substance. Regular use can lead to nicotine addiction, especially among youth and non-smokers.Adverse Effects on the Developing Brain: The brains of adolescents and young adults are still developing, and exposure to nicotine during this critical period can have lasting impacts on cognitive functions, attention, and mood.⁶

Respiratory issues:

Some studies suggest that inhaling e-cigarette aerosol often referred to as "Vaping," may cause respiratory problems. The inhalation of certain chemicals in e- cigarettes can irritate the lungs and lead to conditions such as bronchiolitis obliterans, also known as "popcorn lung." Cardiovascular Risks:

Nicotine, even without the combustion process found in traditional cigarettes, can elevate heart rate and blood pressure, potentially contributing to cardiovascular issues.⁶

Unknown long-term health effects:

E-cigarettes are new, and the long-term health effects of prolonged use are not yet fully understood. Research is ongoing to assess potential risks associated with chronic e-cigarette use.¹

Chemical exposure:

The liquid used in e-cigarettes contains various chemicals, including flavorings and additives.The inhalation of these substances may expose users to potentially harmful compounds, although the extent of the risks is still under investigation.²

Specific study findings:

E-liquid exposure induces the release of extracellular vesicles from bladder cancer cells, promoting non- malignant urothelial cell transformation.⁵ E-cigarette use can induce DNA damage, oxidative stress, and cytotoxicity in oral cells, but adverse effects generally appear less severe compared to conventional smoking. The presence of toxicants in e-cigarette aerosols, with levels approaching those of traditional cigarettes. Controversy exists about the role of nicotine in e-cigarettes, and some studies associate e-cigarette use with bladder cancer.⁵

E-cigarettes over smoking:

E-cigarettes can be harmful to health, particularly for non-smokers and children, adolescents, and young adults. Their effects on many important health outcomes are uncertain. E-cigarettes may be beneficial for smokers who use them to quit smoking completely and promptly, but they are not currently approved smoking cessation aids. Better quality evidence is needed regarding the health impact of e- cigarette use, their safety and efficacy for smoking cessation, and effectiveness. According to one study conventional smoking groups compared to the e- cigarette group. E-cigarettes could not be considered as a better option than conventional smoking, and quitting smoking is still the optimal option.⁶

Individuals with EVALI reported using both nicotine e- cigarettes and cannabinoid e-cigarettes. Major ingredients in nicotine e-cigarettes include vegetable glycerine (VG) and propylene glycol (PG), and they may contain 1–4% flavouring chemicals and 0–10% nicotine (e.g., in reusable tank systems and reusable or disposable pod-based devices).⁷ E-liquid exposure induces bladder cancer cells to release extracellular vesicles that promote non-malignant urothelial cell transformation and can cause testicular cancer.⁸

E-cigarette use can induce DNA damage, oxidative stress, and cytotoxicity in different types of oral cells.⁹ However, the adverse effects of e-cigarette use were found to be less than those of smokers. The presence of toxicants in e-cigarette aerosols suggests that e- cigarette use is not risk-free. Levels of carbonyls formaldehyde, acetaldehyde, and acrolein can approach those from traditional tobacco cigarettes. Flavors may play some role in the toxicity of e- cigarettes. Fruit-flavoured e-liquids are shown to be more toxic than tobacco-flavoured ones. There is controversy about the role that nicotine may play in e- cigarettes. In some studies, e-cigarettes have also been found to be associated with bladder cancer patients.²

Vaping in South-Asia:

Over the last few decades, South Asian countries such as India, Pakistan, and Bangladesh have tried to work effectively to address tobacco control. However, with the looming threat of ENDS and SLT uptake, said countries ought to apply proven tobacco control tools that work for citizens’ holistic health addressing all levels among different age groups. This paper's findings are relevant for developing countries worldwide that have a high tobacco-related health burden, a complex landscape of use, and inadequate resources to offer tobacco cessation and SLT control. With India having implemented a ban on SLT and vaping use, other countries may slowly follow suit. It is essential to account for tobacco control programs and the inter-links these have with SLT and vaping since public health authorities are under-equipped given the lack of research into trends.³

Conclusions:

The study concludes that while e-cigarettes may have potential harms, especially for non-smokers and youth, their effects on health outcomes are uncertain. E-cigarettes may be beneficial for smokers aiming to quit, but more research is needed to understand their safety and efficacy. Quitting smoking is still considered the optimal option based on current findings. In light of the documentation of cases of lung injury associated with the use of e-cigarettes or vaping, the use of these devices should not be recommended as a smoking cessation tool; abstinence from all vaping devices is the best way to prevent primary and recurrent secondary lung injury.