Carcinogens Released from Secondhand Tobacco Smoke

1. Carcinogens Released from Secondhand Tobacco Smoke Jacqueline Le Chem 32A Symposium Lab Section 103, Tuesday: 2:00-5:05 pm

2. Outline • What is Secondhand/ Side stream tobacco smoke? • Harmful components released from side stream tobacco smoke. • NNK (Tobacco-specific carcinogen) and its effects • NNK Metabolism; DNA altering process • Summary • End!

3. Why I chose this topic? • Because I live in a household with smokers I want to be more aware of the effects that come from being exposed to second hand smoke.

4. What is Second Hand Smoke? • Second hand smoke AKA environmental tobacco smoke is a combination of smoke that is released from burning tobacco • Consists of : • 1. Sidestream smoke that is released from the burning end of tobacco/cigarette • 2. Mainstream smoke inhaled by the smoker.

5. Harmful components released from side stream tobacco smoke. • Sidestream smoke releases more harmful toxins than mainstream • More than 300 known toxins that can result in diseases are released • Arsenic, Cadmium( found in batteries) , Chromium , Nitrosamines • N-Nitrosamines: large groups of carcinogens that can cause cauncer in specific tissues and parts of the body, variety of species. • Carcinogens: chemicals capable of inducing cancer in humans and animals with exposure. • Specific nitrosamines include: • N-nitrosodimethylamine • N-nitrosopyrrolidine • certain tobacco-specific N-nitrosamines is as N′-nitrosonornicotine (NNN) • 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)

6. NNK and its cancerous effects • A potent lung carcinogen • NNK was studied & found to be rodent/mice carcinogenic • Carcinogenicity tested on lab mice by injection and inhalations • Rodents started to develop lung tumors , some benign, some malignant • Prolong exposure led to skin tumors and tumors in oral cavity. • Showed signs of lung tumor growth: showing NNK is a carcinogen that targets the lung and induces cancer. • Studies show that urine levels of NNK in SHS people are fairly high • uptake NNK that is released from second hand smoke found humans and link between second hand smoking and the risk of lung cancer.

7. NNK Metabolism • Metabolism of the carcinogens one of the main factors concerning the induction of lung cancer • Body’s natural response: • Metabolic Detoxification: body it automatically puts in motion a process in which it turns the carcinogens into metabolites and tries to transform them into something that can be easily excrement out of the body. • Metabolic Activation: an unforeseen consequence when reactive forms something reactive with electron-deficient center that’s reactive with electron-rich centers in DNA • Results in DNA adducts: DNA covalently bonds with cancer causing substance • DNA adducts persists lead to stop cell growth and tumors , cancers.

8. Link from SHS exposure to cancer via carcinogens

9. Summary • Evidence shows that sidestream smokes does contain many harmful cancer inducing substances. • Exposure to SHS can lead to higher uptake of carcinogens that lead to cancer • Primary reason due to DNA damage

10. Bibliography • Office on Smoking and Health (US). The Health Consequences of Involuntary Exposure to Tobacco Smoke: A Report of the Surgeon General. Atlanta (GA): Centers for Disease Control and Prevention (US); 2006. 2, Toxicology of Secondhand Smoke. Available from: http://www.ncbi.nlm.nih.gov/books/NBK44321/ • ↵ • International Agency for Research on Cancer. Tobacco smoke and involuntary smoking. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans vol. 83. Lyon, France: IARC, 2003. • Jenkins RA, Guerin MR, Tomkins BA. The chemistry of environmental tobacco smoke: composition and measurement, 2nd ed. Boca Raton, Florida: Lewis Publishers, 2000:1–75.

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