To Worry, or not to worry

Smoking on health are serious and deadly. Out of approximately 4000 chemicals in cigarettes, most are toxic. Cigarettes affect everything from the internal functioning of organs to the efficiency of the body's immune system.
Smoking effects on human body
• Nicotine reaches the brain within 10 seconds after smoke is inhaled. It has been found in every part of the body and in breast milk.
• Carbon monoxide binds to hemoglobin in red blood cells, preventing affected cells from carrying oxygen.
• Carcinogens damage important genes that control the growth of cells, causing them to grow abnormally or to reproduce rapidly.
• Smoking affects the function of the immune system and increases the risk for respiratory infections.
• Oxidative stress mutates DNA and leads to chronic lung injury. Oxidative stress is the general mechanism behind the aging process, contributing to the development of cancer and cardiovascular disease.
• The body produces antioxidants to help repair damaged cells. Smokers have lower levels of antioxidants in their blood than do nonsmokers.
Carcinogens in cigarettes
A carcinogen is defined as any substance that can cause cancer. Many chemicals in cigarettes are known to cause cancer.
TSNAs
Tobacco-specific N-nitrosamines (TSNAs) are known to be some of the most potent carcinogens present in smokeless tobacco, snuff and tobacco smoke.
Benzene
Benzene can be found in pesticides and gasoline. It is present in high levels in cigarette smoke and accounts for half of all human exposure to this hazardous chemical.
Pesticides
Pesticides are inhaled into our lungs via cigarette smoke.
Toxic Metals in cigarettes
Toxic / heavy metals are metals and metal compounds that have the potential to harm our health when absorbed or inhaled. In very small amounts, some of these metals support life, but when taken in large amounts, can become toxic.
Arsenic
Commonly used in rat poison, arsenic finds its way into cigarette smoke through some of the pesticides that are used in tobacco farming.
Cadmium
Cadmium is a toxic heavy metal that is used in batteries. Smokers typically have twice as much cadmium in their bodies as nonsmokers.
Poisons in cigarettes
Poison is any substance that causes severe physical distress or death. Approximately 200 poisonous gases have been discovered in cigarette smoke.
Ammonia
Ammonia compounds are used in cleaning products and fertilizers. Ammonia is also used to boost the impact of nicotine in manufactured cigarettes.
Carbon Monoxide
Carbon monoxide is present in car exhaust and is lethal in very large amounts. Cigarette smoke contain high levels of carbon monoxide.
Hydrogen Cyanide
Hydrogen cyanide was used to kill people in the gas chambers in Nazi Germany during World War II. It can be found in cigarette smoke.
Nicotine
Nicotine is a poison used in pesticides and is the major addictive element in cigarettes.