Enviro Flashcards
Environmental diseases are NOT?
genetic
Environmental injuries are often causes by ____ and _____ agents?
chemical and physical
4 types of physical agents that cause injury
mechanical
thermal
electrical
radiation
environmental diseases definition
study of diseases not entirely genetic
- caused by:
1) air/water pollution of the enviro
2) use/abuse of drugs and physical agents (radiation)
3) over/under nutrition
define pollutanta
an agent in the environment which can cause disease if exposure to it occurs
examples of outdoor air pollutants?
ozone, nitrogen dioxide, sulfur dioxide, carbon monoxide, lead particulates
examples of indoor air pollutants
carbon monoxide, wood smoke, formaldehyde, bioaerosols
define smog
visible accumulation of air pollutants
–result of coal combustion produces sulfur oxides
air pollution causes increased morbidity and mortality especially among those with pre-existing ____?
lung disease
define “photochemical oxidant” smog
incompletely burned hydrocarbons release CO, CO2 and nitrogen oxides which are primary pollutants
what does sunlight do in regards to air pollution? example?
sunlight acts on primary pollutants to form secondary pollutants
**ozone and free radicals with oxidizing properties as afflicts Los Angeles
Bhopal disaster
in 1984 a lot of methyl isocyanate (MIC) gas was released in India; still having cancer, respiratory, blindness and birth-defects
what are the factors that affect environmental injury?
1) solubility in water
2) particle size and airway anatomy
3) concentration and chemical reactivity
4) rate, depth, and type (oral or nasal) of respirations
5) duration of exposure
6) host clearance mechanisms
describe how solubility in water affects enviro injury?
*scrubbing?
- more soluble = more dissolvable in upper airway secretions
- scrubbing action of the upper airway passages results in the lower airway passages being protected, for example from SO2
scrubbing action of the upper airway passages does what?
results in the lower airway passages being protected, for example from SO2
describe particle size and airway anatomy and it’s affect on enviro injury
- > 5-10 um doesn’t reach distal airway because it’s too large to fit
- <0-0.5 um gas goes in and out of airway with affect or deposition because so small
- 1-5 um are the most dangerous because they lodge at bifurcations of the distal airways!!!
describe concentration and chemical reactivity and it’s affect on enviro injury
- low (<0.1 ppm) = eye irritation only
- moderate (2-5 ppm) overcome scrubbing action of nose causing increased airway resistance
- very high (> 20 ppm) result in decreased mucociliary clearance and pulmonary edema = MOST problamatic
describe rate, depth, and type (oral or nasal) of respirations and it’s affect on enviro injury? Coal miner example?
Not breathing properly OR the way you breath in your environment
**coal miners breathing is fast and deep due to physical
excursion leading to increased exposure of lower airways to pollutants
describe duration of exposure and it’s affect on enviro injury?
more exposure = more intake of pollution
describe host clearance mechanisms and it’s affect on enviro injury?
decreased capacity to clear inhaled particles
–lung diseases decrease clearance; such as: emphysema, chronic bronchitis, cystic fibrosis
What are some NON-therapeutic agents that can cause injury
1) lead
2) carbon monoxide
lead is dangerous principally to?
infants and children
sources of lead?
are numerous; leaded gasoline, old paints, soil contamination
lead is mostly absorbed by the body where?
80-85% is absorbed lead is taken up by BONES
