Environmental Health and Toxicology

Disease- a change in health for the __________ caused by a number of possible factors.

Illness Factors include diet and nutrition, infectious agents, toxic chemicals, physical factors and ______________ stress.

  • Pathogens- Disease causing organisms, such as bacteria, _________, microorganisms or other parasites.

Antibodies are introduced to prevent disease, by introducing a foreign particle

Morbidity- _________
Mortality- death

The Top Three Leading killers worldwide

    1. Cardiovascular Disease
    2. _________ and Tumors
    3. Infectious and Parasitic diseases (24%)

    Higher Death Rates occur in less fortunate counties where conditions are not ideal for human health and survival

    Pesticides- used to eliminate insect vectors.  Problem: Insects tend to become very resistant to the pesticides being used to destroy them, therefore allowing the insect population to come back and infect others

    Currently, death rate is decreasing and life expectancy is increasing

**AIDS**- the largest cause of communicable deaths in the world...killing ____ MILLION people in YEAR 2008!!!

  • Over 33 million people are currently living with HIV (_____% are women).
  • AIDS- _______ million people have died so far since inception
  • Largest occurrence in Africa. Africa has 14 million AIDS orphans.
  • Drug addictions and ____________ sex are the two main causes
  • Places such as Botswana, Zimbabwe and Zambia tend to have survival only of the very young and very ______, as the middle ages of those living in these communities have died due to AIDS

Other Diseases

    Viruses

  • Ebola- _____% Mortality

   Bacteria

  • Tuberculosis- 256 cases _________ to drugs
  • Anthrax- bacteria spores are highly lethal
  • Botulism- most recognized in Botox injections (_________ purposes)
  • Cholera- bacterial infection causing exhaustive diarrhea

   Malaria- One _________ die a year

  • DALY or The Disability-Adjusted ______ Years measure the total burden of disease on productivity and quality of life.
    • DALY measures are very high in poor countries such as Africa due to lack of sanitation and polluted drinking water
  • Malnutrition makes people more susceptible to many diseases
  • Approximately 2 billion people suffer from worms, flukes, protozoa and other internal parasites ...affects the immune system greatly!
  • Flu Epidemic of 19_____ was LARGEST loss of life from an individual disease in a single year...(between 30 and 40 million)
    • Most flu strains are transmitted by air, or by pigs, ________, monkeys and rodents
    • As population grows, the faster a disease will spread
    • Outbreaks can occur among ___________ as well
  • Strep is the most common form of hospital-acquired conditions

Toxicology (Toxic and Hazardous Materials)

Hazardous = __________, including flammables, explosives, irritants, sensitizers, acids and caustics

Toxins = poisonous- so damaging that they damage living organisms by _________ cells

Allergens = substances that activate the ___________ system, can act directly as antigens

Antigens - foreign white blood cells

Four Main Categories of TOXINS

  1. ____________- kill neurons in the nervous system quickly ...example Mercury and Lead, DDT, organophosphates
  2. Mutagens- chemicals and radiation that cause ___________ by altering DNA. can trigger cancer and is inheritable if in reproductive cells. no safe level.
  3. Carcinogens- substances that cause _________

    The Delaney Clause to the US Food and Drug Act states that no known carcinogen causing "reasonable harm" may be added to food and drugs.

    1:2 males (mostly ________) and 1:3 females (mostly lung and ________) in US have cancer

  4. Teratogens- toxins that cause abnormal embryonic cell division and result in ________ defects ...example alcohol (fetal alcohol syndrome) and thalidomide (sedative causing abnormal fetal development)

Diet has a huge impact on your health. Eat real food, not too much, mostly plants.

 

Measuring Toxicity

The ______/Response Curves- a graph that shows the dosage that causes death in a population of organisms as the dosage level of a toxin is increased.

Not always symmetrical, making it difficult to compare toxicity of unlike chemicals

LD50- measures toxicity of a chemical, LD50 is the dose lethal to _____% of a test population; the lower the LD50, the more toxic the chemical

  • The established dose curve will determine the dose below which none of the test subjects were harmed.
  • The threshold dose is the level at which a negative effect is just starting to occur as the toxin level increases.

Bio______________ of a toxin occurs when an organism absorbs and stores the toxin in its tissues

Biomagnification when the toxin becomes increasingly more concentrated higher up the ___________ chain.The best-known examples are the insecticide DDT and mercury.

 

Risk Assessment

  • Calculating the risk of becoming ill when exposed to a toxin or pathogen
  • Many public health decisions are based on our risk of becoming ill

 

Famous Cases

"Silent Spring" written by Rachel Carson explored the persistence of _______ pesticides in the environment, biomagnification and effect on non-target species

_________ Canal- Superfund Site in Canal Buffalo, NY. Site was used as an industrial dump for several toxic chemicals and later filled in to build a community school and residential homes. Cluster of illness led Lois Gibbs to fight for clean up.

Other cases include Bhopal, Chernobyl, Minamata, Three Mile Island, Fukushima Nuclear Crisis, Kuwaiti Oil Fires, Deep Water Horizon Oil Spill, Exxon Valdez, and Seveso Dioxin Cloud.

Acute Toxicity occurs when a large dose inflicts ____________ harm on an organism

Chronic Toxicity occurs when a __________ dose is expressed over a long period of time, harder to detect because it may not be seen for ________

Chemical Synergism- when two toxins __________ have a greater effect than the SUM of the effects of the two toxins separately ...example/ small amount of alcohol with small amount of _____________ can have a severe effect on the central nervous system...or smoking and ___________ can expose a person to cancer ten times greater than if they were exposed to just one of the factors.

Best way to destroy these chemicals and toxins-through neutralization or oxidation... Incineration, Air Stripping, Carbon Absorption or Flocculation

Waste Disposal ...Landfills and Dumps- there is no away. Incineration is a huge problem creator. Selling the Waste to Poor Counties just poisons the people whose country accepts the waste.

HAZMAT (Hazardous Materials) Alternatives- You can replace your everyday cleaner with the right combination of harmless substances ...things such as ________ Juice, Vinegar, Water, _______ Soda and so much more can replace more hazardous chemicals to make the result safer

Conserve, Recycle and ______________!