Session 2

Chapter 3

Living with Nature

Understanding Environmental Health 

Chapter Three Slides:

Key Concepts:

1. The human body provides a habitat for other, much smaller organisms, some of which make us sick.

2. The human body mounts a defense against pathogens.

3. The effort to manage infectious disease risk incorporates several different approaches.

4. When people are close to one another, pathogens can be transmitted from one person to another simply through proximity; this is transmission through closeness or contact.

5. Airborne transmission of pathogens is distinct from transmission via respiratory droplets in the air.

6. Fecal–oral pathways for the transmission of infectious disease are important in public health.

7. Foodborne illness emerges as a distinct phenomenon only where there is clean tap water.

8. The keys to food safety in the kitchen are (1) preventing contamination by pathogens as much as possible and (2) managing time and temperature to minimize the growth of populations of pathogens when prevention fails.

9. The term vectorborne disease refers specifically to diseases transmitted by a biological vector.

10. Infectious disease is an important cause of mortality and morbidity on a global scale.

11. In the United States, responsibilities related to infectious disease are divided between state governments and the federal government.

12. Certain plants, animals, and fungi produce poisons that are acutely toxic to humans. Most of these cause relatively isolated incidents of poisoning in individuals or local groups. In contrast, exposures to aflatoxin create a substantial public health burden.

13. Allergy and asthma, which are conditions of the immune system, have been linked to some environmental factors.

14. Mortality from natural disasters is highly variable over time, but certain types of disasters tend to cause very high mortality when they occur.

15. Some isotopes of certain chemical elements are radioactive: an unstable isotope ejects part of its nucleus, thus emitting radiation and “decaying” into a different element.

16. Radioactive decays occur in characteristic series; each isotope in the chain has a characteristic half-life, and each decay emits a characteristic type of radiation.

17. In public health, we make a key distinction between radiation that has enough energy to create charged ions in the body and radiation that does not have enough energy to do this.

18. From a public health standpoint, alpha, beta, and gamma radiation pose distinct hazards in terms of the intensity of their damage to tissue and in terms of the shielding required to protect against them. These two issues are related.

19. Ionizing radiation’s biological effects are relatively well established and depend on the level of exposure.

20. People are routinely exposed to naturally occurring radiation, both ionizing and nonionizing.

21. Naturally occurring radiation, both ionizing and nonionizing, has impacts on human health.

Links

Chapter 3: Living with Nature

Homework: Read this session's assignment. Answer all of the discussion questions found at the end of each chapter  for the assigned chapters and email the attached questions and answers in Word or pdf format to Canvas email by 5 pm on Sunday the last day of Session 2.  In the title box in the email please put Enviro Health Session 2.