What harmful substances are contained in cigarettes?

The heavy metals in cigarettes are mainly arsenic, lead and cadmium. The data show that arsenic compounds are completely absorbed by respiratory mucosa, and arsenic will not actively accumulate in epithelium and skin appendages such as hair, nails and bones when ingested for a long time. Long-term inhalation of cadmium will damage the kidneys and lungs, leading to emphysema and renal insufficiency. Lead inhaled by human body diffuses into blood circulation through alveoli, and long-term inhalation of lead smoke can cause chronic lead poisoning.

Extended data:

The influence and harm of cigarettes;

Tolerance and dependence: Regular smoking can keep the nicotine content in the brain at a high level. Neuron receptors are less and less sensitive to nicotine, and their stimulating effect on dopamine release is also weakened. The original cigarette consumption can no longer satisfy the pleasure of smokers, and smokers are tolerant of nicotine.

When smokers stop smoking for a few hours (sleep time), the nicotine content in the body will drop and the neuron receptors will become extremely sensitive. At this time, the activity of acetylcholine exceeds the normal level, which makes smokers become irritable and want to smoke very much.

At this time, if you can smoke a cigarette, you can over-stimulate neuronal receptors and promote the release of dopamine in large quantities. Through this phenomenon, we can understand why the first cigarette every day can bring great pleasure to "old smokers", and smokers are therefore caught in a vicious circle of more and more addiction.

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