Lecture 9: Air Pollution Flashcards
T/F: Globally, air pollution is the #1 cause of early
death compared to any other toxicant group
true!!
T/F: There was rapid and relatively
unregulated industrial
expansion and the burning of
fossil fuels (especially coal)
until ~1950s
true!!
what was the “great smog”?
happened in London 1959, lasted 5 days because of cold weather with a temperature inversion (kept everything trapped in the lower atmosphere)
During that time, 1,000 tons of smoke particles,
2,000 tons of carbon dioxide, 140 tons of
hydrochloric acid, 14 tons of fluorine compounds
and 370 tons of sulfur dioxide was released into the
air.
* Contributed to the deaths of between 4000-12000
people (mostly elderly and children)
what led to the creation of air pollution control legislation?
the great smog, and other smog events across NA
______ is now the largest contributor to air pollution in
North American cities
Automobile exhaust
T/F: Globalization has led to the
outsourcing of manufacturing to
other countries… Which contributes
to air pollution elsewhere
true!
_____ is comprised of four main
air pollutants:
- particulate matter
- ozone (O3)
- nitric oxides (e.g., NO2)
- sulfur oxides (e.g., SO2)
Smog
what happens with acute lung injury? (4)
oxidative damage
airway reactivity
pulmonary edema
cell proliferation
______ in acute lung injury: Ozone, NO2, tobacco smoke and lung
immune system cells can all generate ROS
oxidative damage
______ in acute lung injury: Air pollutants can trigger
bronchoconstriction, limiting oxygen uptake.
* Problematic with asthma sufferers
airway reactivity
______ in acute lung injury: Extensive cellular damage causes leaking
of fluid into alveolar spaces.
* Less gas exchange
pulmonary edema
______ in acute lung injury: Epithelial cells proliferate, excessive cell
division can lead to an increased potential
for mutations
cell proliferation
what happens with chronic lung injury?
COPD
fibrosis
asthma
cancer
______ in chronic lung injury: Emphysema = destruction of the alveolar sacs.
* Bronchitis = constant inflammation of bronchi +
excessive mucous deposition.
* Increase in lung infections
COPD, chronic obstructive pulmonary disorder
______ in chronic lung injury: Inflammation response leading to increased
deposition of collagen in damaged lungs.
* Makes lungs less elastic, decreasing gas
exchange.
fibrosis
______ in chronic lung injury: Recurrent bronchoconstriction
asthma
______ in chronic lung injury: Direct DNA mutations from oxidative damage.
* Indirect DNA mutations from excessive cell
division to replace damaged cells
cancer
_________ is a large mixed class of
compounds (i.e., anything that’s small, for example
dust and soot)
Particulate matter
what are the four classifications of particulate matter?
PM100 = dust = particles >100 µm.
PM10 = coarse = particles 2.5-10 µm.
PM2.5 = fine = particles 0.1-2.5 µm.
PM0.1 = ultrafine = nanoparticles = <0.1 µm
T/F: Other toxicants can absorb onto the surface of
particles (metals, gasses, pesticide residue, etc.)
exacerbating the PM effects
true!
T/F: worldwide estimates suggest that particulate matter can cause
up to 25% of lung cancer deaths, 8% of COPD deaths, and
about 15% of heart disease and stroke
true!!
______ is heterogeneous and usually associated with other types of pollution,
so it is difficult to assess a direct mechanism of toxicity.
PM, particulate matter
what are the five possible mechanisms that PM uses to be toxic?
- Leads to lung irritation which
leads to increase permeability
in lung tissue; - Increases susceptibility to
viral and bacterial pathogens
leading to pneumonia in
vulnerable persons who are
unable to clear these infections; - Aggravates the severity of
chronic lung diseases
causing decreased lung
function - Causes inflammation of
lung tissue, resulting in the
release of chemicals that
impact heart function; - Causes changes in blood
chemistry that can
contribute to heart attacks
T/F: Estimates that reducing PM to WHO
recommended levels would prevent 15% of air
quality related deaths
true!!!!
