Diane-Michel.com

Zheng W, Lee SA.

Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, TN 37203-1738, USA. wei.zheng@vanderbilt.edu

PMID: 19838915 [PubMed - in process]

Resource:  National Cancer Institute

1.  
   • arsenic (a heavy metal toxin)
   • benzene (a chemical found in gasoline)
   • beryllium (a toxic metal)
   • cadmium (a metal used in batteries)
   • chromium (a metallic element)
   • ethylene oxide (a chemical used to sterilize medical devices)
   • nickel (a metallic element)
   • polonium–210 (a chemical element that gives off radiation)
   • vinyl chloride (a toxic substance used in plastics manufacture)
2. What is secondhand smoke?
3. How is secondhand smoke exposure measured?
4. Does secondhand smoke contain harmful chemicals?
5. Does exposure to secondhand smoke cause cancer?
6. What are the other health effects of exposure to secondhand smoke?
7. What is a safe level of secondhand smoke?
8. What is being done to reduce nonsmokers’ exposure to secondhand smoke?

Secondhand smoke (also called environmental tobacco smoke) is the combination of sidestream smoke (the smoke given off by the burning end of a tobacco product) and mainstream smoke (the smoke exhaled by the smoker) (1, 2, 3, 4). Exposure to secondhand smoke is also called involuntary smoking or passive smoking. People are exposed to secondhand smoke in homes, cars, the workplace, and public places such as bars, restaurants, and other recreation settings. In the United States, the source of most secondhand smoke is from cigarettes, followed by pipes, cigars, and other tobacco products (4).

 Secondhand smoke is measured by testing indoor air for nicotine or other smoke constituents. Exposure to secondhand smoke can be tested by measuring the levels of cotinine (a nicotine by-product in the body) in the nonsmoker’s blood, saliva, or urine (1). Nicotine, cotinine, carbon monoxide, and other evidence of secondhand smoke exposure have been found in the body fluids of nonsmokers exposed to secondhand smoke.

Yes. Of the more than 4,000 chemicals that have been identified in secondhand tobacco smoke, at least 250 are known to be harmful, and 50 of these are known to cause cancer. These chemicals include (1):

Many factors affect which chemicals are found in secondhand smoke, including the type of tobacco, the chemicals added to the tobacco, the way the product is smoked, and the paper in which the tobacco is wrapped (1, 3, 4).

 

Yes. The U.S. Environmental Protection Agency (EPA), the U.S. National Toxicology Program (NTP), the U.S. Surgeon General, and the International Agency for Research on Cancer (IARC) have classified secondhand smoke as a known human carcinogen (cancer-causing agent) (1, 3, 5).

Inhaling secondhand smoke causes lung cancer in nonsmoking adults (4). Approximately 3,000 lung cancer deaths occur each year among adult nonsmokers in the United States as a result of exposure to secondhand smoke (2). The Surgeon General estimates that living with a smoker increases a nonsmoker’s chances of developing lung cancer by 20 to 30 percent (4).

Some research suggests that secondhand smoke may increase the risk of breast cancer, nasal sinus cavity cancer, and nasopharyngeal cancer in adults, and leukemia, lymphoma, and brain tumors in children (4). Additional research is needed to learn whether a link exists between secondhand smoke exposure and these cancers.

Secondhand smoke causes disease and premature death in nonsmoking adults and children (4). Exposure to secondhand smoke irritates the airways and has immediate harmful effects on a person’s heart and blood vessels. It may increase the risk of heart disease by an estimated 25 to 30 percent (4). In the United States, secondhand smoke is thought to cause about 46,000 heart disease deaths each year (6). There may also be a link between exposure to secondhand smoke and the risk of stroke and hardening of the arteries; however, additional research is needed to confirm this link.

Children exposed to secondhand smoke are at an increased risk of sudden infant death syndrome (SIDS), ear infections, colds, pneumonia, bronchitis, and more severe asthma. Being exposed to secondhand smoke slows the growth of children’s lungs and can cause them to cough, wheeze, and feel breathless (4).

There is no safe level of exposure to secondhand smoke. Studies have shown that even low levels of secondhand smoke exposure can be harmful. The only way to fully protect nonsmokers from secondhand smoke exposure is to completely eliminate smoking in indoor spaces. Separating smokers from nonsmokers, cleaning the air, and ventilating buildings cannot completely eliminate secondhand smoke exposure (4).

Many state and local governments have passed laws prohibiting smoking in public facilities such as schools, hospitals, airports, and bus terminals. Increasingly, state and local governments are also requiring private workplaces, including restaurants and bars, to be smoke free. To highlight the significant risk from secondhand smoke exposure, the National Cancer Institute, a component of the National Institutes of Health, holds meetings and conferences in states, counties, cities, or towns that are smoke free, unless certain circumstances justify an exception to this policy.

More information about state-level tobacco regulations is available through the Centers for Disease Control and Prevention (CDC) State Tobacco Activities Tracking and Evaluation (STATE) System Web site. The STATE System is a database containing up-to-date and historical state-level data on tobacco use prevention and control. This resource is available at http://apps.nccd.cdc.gov/statesystem/ on the Internet.

On the national level, several laws restricting smoking in public places have been passed. Federal law bans smoking on domestic airline flights, nearly all flights between the United States and foreign destinations, interstate buses, and most trains. Smoking is also banned in most Federally owned buildings. The Pro-Children Act of 1994 prohibits smoking in facilities that routinely provide Federally funded services to children.

The U.S. Department of Health and Human Services (DHHS) Healthy People 2010, a comprehensive, nationwide health promotion and disease prevention agenda, includes the goal of reducing the proportion of nonsmokers exposed to secondhand smoke from 65 percent to 45 percent by 2010 (7). More information about this program is available on the Healthy People 2010 Web site at http://www.healthypeople.gov/ on the Internet.

Internationally, several nations, including France, Ireland, New Zealand, Norway, and Uruguay, require all workplaces, including bars and restaurants, to be smoke free.

Selected References

1. National Toxicology Program. Report on Carcinogens. Eleventh Edition. U.S. Department of Health and Human Services, Public Health Service, National Toxicology Program, 2005. 
2. National Cancer Institute. Cancer Progress Report 2003. Public Health Service, National Institutes of Health, U.S. Department of Health and Human Services, 2004. 
3. International Agency for Research on Cancer. Tobacco Smoke and Involuntary Smoking. Lyon, France: 2002. 
4. U.S. Department of Health and Human Services. The Health Consequences of Involuntary Exposure to Tobacco Smoke: A Report of the Surgeon General. Rockville, MD: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, Coordinating Center for Health Promotion, National Center for Chronic Disease Prevention and Health Promotion, Office on Smoking and Health, 2006. 
5. U.S. Environmental Protection Agency. Respiratory Health Effects of Passive Smoking (Also Known as Exposure to Secondhand Smoke or Environmental Tobacco Smoke–ETS). U.S. Environmental Protection Agency, 1992. 
6. California Environmental Protection Agency, Office of Environmental Health Hazard Assessment. Proposed Identification of Environmental Tobacco Smoke as a Toxic Air Contaminant: Part B Health Effects, 2005. 
7. U.S. Department of Health and Human Services. Healthy People 2010: Understanding and Improving Health. 2nd ed. Washington, DC: U.S. Government Printing Office, 2000. 

Related NCI materials and Web pages:

• National Cancer Institute Fact Sheet 10.16, Questions and Answers About Cigar Smoking and Cancer
  (http://www.cancer.gov/cancertopics/factsheet/Tobacco/cigars)
• National Cancer Institute Fact Sheet 10.19, Quitting Smoking: Why To Quit and How To Get Help
  (http://www.cancer.gov/cancertopics/factsheet/Tobacco/cessation)
• Smoking and Tobacco Control Monograph 10: Health Effects of Exposure to Environmental Tobacco Smoke
  (http://cancercontrol.cancer.gov/tcrb/monographs/10/index.html)
• NCI’s Smoking and Cancer Home Page
  (http://www.cancer.gov/cancertopics/smoking)

For more help, contact:

NCI’s Cancer Information Service
Telephone (toll-free): 1–800–4–CANCER (1–800–422–6237)
TTY (toll-free): 1–800–332–8615
LiveHelp^® online chat: https://cissecure.nci.nih.gov/livehelp/welcome.asp

Reference:

National Cancer Institute (2009). Secondhand smoke questions and answers.  Retrieved November 2, 2009 from http://www.cancer.gov/cancertopics/factsheet/Tobacco/ETS

Resource:  National Cancer Institute

October is National Breast Cancer Awareness Month. As the federal government’s leading funder of breast cancer research, the National Cancer Institute supports a wide range of research to improve prevention, detection, and treatment of breast cancer. NCI also funds research on follow-up care for the growing number of breast cancer survivors. Take a look at some recent advances and selected resources, including a video.

On this page

Understand Your Risk

• Understanding  Breast Changes discusses common breast changes at various times of  life, types of follow-up testing, and types of biopsies. It helps women understand their screening results and emphasizes that not all breast changes mean cancer.
• Estimating Breast Cancer Risk describes the Breast Cancer Risk Assessment Tool, an online tool developed by NCI and others to help health care providers estimate a woman’s individual risk of breast cancer.
• The Breast Cancer Prevention Summary (PDQ®) provides an overview of factors that may raise or lower your risk of breast cancer. There is also information about clinical trials that study ways to lower the risk of developing breast cancer.
  • See a list of U.S. breast cancer prevention clinical trials that are open to new participants.
• Both men and women who have certain mutations in their BRCA1 or BRCA2 genes have an increased risk of breast cancer. See BRCA1 and BRCA2: Cancer Risk and Genetic Testing.

Steps Toward Better Detection and Treatment

Screening and Detection

• Women should get a mammogram every one to two years beginning at age 40 to check for breast changes.
  • See the NCI Fact Sheet about mammograms.
  • For an overview of tests commonly used to screen for breast cancer, see the Breast Cancer Screening (PDQ®) summary.
• Improving mammography is the goal of the NCI-supported Breast Cancer Surveillance Consortium (BCSC), which gathers and pools data from around the country into a centralized database on women undergoing mammography.
  • See Improving Mammography Quality, Expanding Screening Research in the NCI Cancer Bulletin.
• See a list of U.S. breast cancer screening and detection clinical trials open to new participants.

Treatment

• The Breast Cancer Treatment (PDQ®) summary provides an overview of current standard treatment options.
  • See a list of U.S. breast cancer treatment clinical trials open to new participants.
• The NCI factsheet Adjuvant and Neoadjuvant Therapy for Breast Cancer explains side effects, risks, and benefits of two different types of breast cancer therapy.  Adjuvant therapy is treatment given after primary therapy to increase the chance of long-term survival. Neoadjuvant therapy is treatment given before primary therapy.
• Weekly Paclitaxel Improves Breast Cancer Survival summarizes the results of a randomized clinical trial showing that weekly doses of the drug paclitaxel (Taxol®) after surgery and standard chemotherapy improves disease-free and overall survival in women with breast cancer.

• “Targeted Therapies for Breast Cancer” is an animated tutorial focusing on targeted therapies that have been and are being developed to treat breast cancer. It describes important molecular pathways in breast cancer cells and discusses new therapeutic agents, including small molecules and monoclonal antibodies that target these pathways.
  • Animated/Flash Version (Flash – 15.00 min.)
  • HTML/Accessible Version (For low-bandwidth connections)

Life after Breast Cancer

• Lymphedema, a condition in which lymph fluid builds up in damaged soft body tissues and causes swelling, can be a painful side effect of breast cancer treatment.
  • For information about this condition, see the Lymphedema (PDQ®) summary.

• Slowly progressive weight lifting did not aggravate limb swelling among breast cancer survivors with lymphedema, according to a randomized clinical trial (see the story).
• Cognitive changes associated with chemotherapy for breast cancer and other kinds of cancer may, in about 20 percent of survivors, persist after treatment has ended. See Delving into Possible Mechanisms for Chemobrain in the NCI Cancer Bulletin.
• Other NCI resources related to cancer survivorship include
  • Follow-Up Care After Cancer Treatment
  • Facing Forward: Life After Cancer Treatment
  • NCI’s Office of Cancer Survivorship

General Breast Cancer Information

• The Breast Cancer Home Page is NCI’s gateway Web page to information about breast cancer.
• What You Need To Know About™ Breast Cancer is a patient education booklet about the disease.
• A Snapshot of Breast Cancer provides key information about  disease incidence and mortality, NCI funding trends, relevant research activities, and recent scientific advances.