What makes cigarettes so toxic and dangerous?

There are 4,000 chemical components found in cigarettes and at least 250 of them are harmful to human health, according to the Centers for Disease Control and Prevention

Tar is solid, inhaled chemicals linked with an increased risk for cancer. It also leaves a sticky, brown residue on your lungs, teeth and fingernails.

The top 3 worst chemicals that are in cigarettes
1: NICOTINE one of the most important ingredient in cigarettes. Nicotine is an addictive psychoactive alkaloid. It increases blood pressure and constricts veins and arteries.
2: BENZENE It increases the possibility of developing leukemia and damages nerve systems
3:FORMALDEHYDE .This gas is used to preserve dead bodies
and causes nasal cancer.

This is very harsh is it but is also contains There are over 4,000 chemicals in tobacco smoke and at least 69 of those chemicals are known to cause cancer.