health risks

Health Risks and the Environment

Contents of Entire Course

Cancer
Minerals, Rocks and People

adapted to HTML from lecture notes of Prof. Stephen A. Nelson Tulane University

Cancer
The following data are from the September 1996 issue of Scientic American, Special Issue on "What You Need to Know About Cancer"

Note that environmental pollution is responsible for only 2% of all fatal cancers.

Causes of Fatal Cancers
The following data have been calculated based on the information
shown in the graph on page 94 of the September 1996 issue of Scientific American

Cause	%
Smoking	30
Diet and Obesity	30
Perinatal and Excessive Growth	8
Biological Agents	8
Occupational Factors	8
Alcohol	3
Sedentary Life Style	3
Reproductive Factors	3
Ionizing and Ultraviolet Radiation	2
Environmental Pollution	2
Inherited Genes	2
Food Additives (including Salt)	1
Medical Products and Procedures	1

Causes of Death in 1992	Rate	%
All Causes	852.9	100.0
1. Diseases of the Heart	281.4	33.0
2. Cancer	204.1	23.9
3. Cerebrovascular diseases	56.4	6.6
4. Chronic obstructive pulmonary diseases	36.0	4.2
5. Accidents and adverse effects	34.0	4.0
. . . Motor vehicle accidents	16.1	1.9
. . . All other accidents and adverse effects	18.0	2.1
6. Pneumonia and influenza	29.7	3.5
7. Diabetes	19.6	2.3
8. HIV	13.2	1.5
9. Suicide	12.0	1.4
10. Homicide and legal intervention	10.0	1.2
11. Chronic liver disease	9.9	1.2
12. Kidney Diseases	8.7	1.0
13. Infections	7.7	0.9
14. Atherosclerosis	6.6	0.8
15. Birth Problems	6.2	0.7
. . . All other causes	117.6	13.

The following has been abstracted from the article "Strategies for Minimizing Cancer Risk" by Willett, Colditz and Mueller, September 1996 issue of Scientific American p. 88 to 99.

They suggest that most types of cancer are preventable and that the "war on cancer" which has emphasized improved cancer treatment has had only limited success. The efforts of the "war on cancer" should be better balanced with more extensive efforts to reduce cancer. They suggest that about about two-thirds of cancers could be prevented. Inherited genes that cause a very high risk of getting cancer are responsible for only 2% of fatal cancers. About 30% of cancers are probably not preventable.

They recommend that to reduce your chances of getting cancer, you should:

Eat plenty of fruits and vegetables

Exercise regularly

Avoid weight gain

Avoid tobacco smoke

Avoid animal fats

Avoid red meat

Avoid excessive alcohol consumption

Avoid the midday sun

Avoid risky sexual practices

Avoid known carcinogens in the environment or workplace

Minerals, Rocks and People
Asbestos
- A group of minerals with high length to width ratios

- 95% of asbestos mined is chrysotile

- 5% is crocidolite and amosite

Miners who mine chrysotile seem to have no higher rate of disease than the general public.

People exposed to crocidolite do have a high incidence of the diseases.

EPA makes no distinction between these two with regards to its policies.

Asbestosis

- Decreases lung efficiency.

- Is usually the result of a long-term occupational exposure to asbestos

Mesothelemia

- Cancer of stomach and lung lining.

Black Lung

- Results from the repeated enhalation of coal dust.

Silicosis

- Results from long term inhaling of fine grained quartz.