Is hookah without tobacco harmful?

Water pipes without tobacco are also harmful to health. They release a variety of known carcinogens and toxic substances, and their harmfulness is comparable to that of traditional water pipes, and in some cases even higher.
A large number of scientific studies have confirmed that "tobacco-free" or "herbal" hookahs are not safe alternatives. Their hazards mainly stem from the following three core facts:
The sources of harm are not limited to tobacco.
When smoking hookah, whether it is traditional tobacco or herbal mixtures, wood charcoal is needed to continuously heat the substance. This heating process itself generates a large amount of harmful substances. The water in the hookah cannot effectively filter these toxic substances; it mainly serves to cool and moisten the smoke for inhalation.
"Smokeless" hookahs produce the same amount of toxins
A comparative study involving the World Health Organization (WHO) found that compared to traditional tobacco-containing hookahs, smokeless hookahs do not significantly reduce the levels of major toxins such as carbon monoxide (CO), tar, polycyclic aromatic hydrocarbons (PAH), and volatile aldehydes.
A more extreme case: Some studies have found that certain carcinogens and polycyclic aromatic hydrocarbons in the smoke of non-tobacco water pipes even exceed those in traditional tobacco products. At the same time, some non-tobacco water pipe products have also detected toxic heavy metals, such as lead, chromium and arsenic.
The damage to health is exactly the same.
The in vitro study of alveolar cells confirmed that both tobacco-free and tobacco-containing shisha smoke would significantly inhibit cell proliferation and cause cell cycle arrest. The conclusion clearly states that, apart from not being exposed to nicotine, using tobacco-free shisha is no safer than using traditional tobacco products. This means that users will face similar disease risks as those using traditional shisha, including lung cancer, oral cancer, cardiovascular diseases, etc.
In addition, several common misunderstandings need to be guarded against:
"Herbal" ≠ Safe: Merchants often use labels such as "natural" and "herbal" for marketing purposes, but this does not change the fact that harmful substances are produced after combustion. Any smoke produced by combustion is harmful when inhaled into the lungs.
"Without nicotine" ≠ "harmless": Although smokeless tobacco products can prevent nicotine addiction, as mentioned above, the other toxins and health risks they bring have not been reduced.
Water cannot filter out toxins: This is a widely spread misconception. The water in a water pipe cannot effectively remove harmful chemicals such as tar and carbon monoxide.
Social risks still exist: Sharing a pipe among multiple people increases the risk of transmitting infectious diseases (such as herpes and hepatitis) through saliva.
In summary, any form of hookah, regardless of whether it contains tobacco or not, is unsafe. The smoke from it contains a large amount of known carcinogens and toxic substances, and its harmfulness is comparable to that of cigarettes or even more severe.