Week 9 Flashcards
what are some examples of technological hazards?
they can vary from a single toxic gas leak to an entire industry (e.g. nuclear energy)
includes exposure to hazardous materials, chemical spills, and infrastructure failures
can also include hybrid disasters (caused by natural disasters)
e.g. an earthquake that causes an oil spill from a pipeline
OR
technological disasters involving the environment
e.g. the sinking of the titanic and explosion of the challenger space shuttle
describe the vulnerability to technological disasters
typically, the death tolls from technological hazards are relatively low
vulnerability is greatest for those involved in specific industries of transportation systems
workers in resource industries in hinterlands (remote/isolated area) are at higher risk (e.g. miners)
what are the different categories of technological hazards? differentiate between them
widespread
—- long term (hazards that lead to cumulative effects)
rare events
—- e.g. airplane crashes, mine collapse, shipwrecks
relatively common
—- e.g. automobile accidents, poisons
what is cumulative effects aka widespread technological hazards?
conditions that worsen slowly over time as exposure to a concentration increases
eventually, the concentration reaches a threshold critical to human health
hazards with cumulative effects include exposure to radiation, toxic chemicals, acid precipitation, and groundwater
how is risk calculated / defined for the different types of technological hazards?
infrastructure (bridges, dams, pipelines)
—- risk is defined as the probability of failure during the lifetime of the structure
transportation (travel by road, sea, rail)
—- risk is the probability of death or injury per km travelled
industry (manufacturing, energy production)
—- risk is the probability of death or injury per person per number of hours exposed
what is radon? describe it as a hazard
the 2nd leading cause of lung cancer in North America
primary source of radon gas is from the natural decay of uranium in rock and soil
when radon is inhaled it decays to polonium and lodges in the lungs where it damages tissues
radon becomes a hazard when it is released into our living space
it is difficult to detect because the gas is odourless, colourless, and tasteless
radon detectors are commercially available in areas where it is of greater concern
how does radon enter a house?
the gas can move quickly thru non-saturated soil and can seep into homes
basements are at higher risk especially in winter due to reduced air circulation
what are genetically modified organisms?
these are organisms that have had changes made to their DNA by the transfer of genes
the most common crops that are genetically modified are corns, soybeans, canola, and wheat
crops are modified to increase yields
some crops have been genetically engineered to have greater resistance to
—- extreme changes in temperature or precipitation
—- herbicides
—- pests
—- acidic soil
what are some notable genetic modifications?
chickens that lay low-cholesterol eggs
tomatoes that reduce the risk of cancer
rice with vitamin A
what is the take on genetically modified food?
scientists believes that the benefits outweigh the potential risks but most support more research studies
the UN Food and Agriculture Organization believes that genetically modified crops have great benefits especially in developing countries
describe the impacts of radiation on people
the impact of radiation can be direct (effects are evident within days of exposure) or delayed and chronic (leukemia, cancer)
the impact could be indirect in the form of genetic effects (passing onto offsprings) such as chromosomal changes or birth defects
what are the potential sources of radiation
mining of uranium
—- in Canada, uranium is mined in Northern Saskatchewan and Northern Ontario
—- mines produce wastes known as tailings that can be radioactive hazard
production of electricity
—- uranium is used in nuclear power plants
describe the location of nuclear power plants in North America
most found in the eastern half of North America
they must be near sources of coolant (rivers or lakes)
they must be located near a market for electricity (eastern North America is much more populated)
why is nuclear considered to be a clean source of energy?
because it doesn’t emit greenhouse gases that cause climate change
what is a nuclear meltdown?
an informal term for an accident that results in damage from overheating
it occurs when the heat generated by a nuclear plant exceeds the heat removed by its cooling systems
in a meltdown, fuel rods turn to liquid and the walls of the plant could melt from the extreme heat
the hot liquid could melt thru the bottom of the plant and seep into the soil
describe the three mile island nuclear accident
this is the worst nuclear disaster in US history
it occurred in March 1979
one of the two power plants on three mile island, Pennsylvania experienced a partial meltdown
it was caused by a failure of a valve that controlled cool water entering the plant
there were no direct injuries, minor amount of radiation was released, and the plant closed
describe the Chernobyl nuclear accident
the worst nuclear in world history, occurring in April 1986
the accident was a result of a flawed design, operator error, and disregard of safety regulations
an explosion at the plant caused the immediate deaths of three workers. within one year, 28 more workers died from extreme radiation exposure
over the following 2 decades, thousands of people developed thyroid cancer attributed to radiation exposure
when did the last remaining coal power plant in Ontario close?
in 2014
following the three mile island and Chernobyl incident, nuclear development slowed for a time… why did it pick up again?
concern over greenhouse gas emissions created a high demand for cleaner sources of energy
the province has invested in refurbishing existing nuclear power plants and is planning to build new ones as well
describe the titanic and its shipwreck
the titanic was a passenger ocean liner that struck an iceberg and sank on its maiden voyage
it left Southampton, England and was bound for NYC
the ship was designed using advanced technology and was believed to be unsinkable
there was a high death toll due to the lack of lifeboats for all passengers
what was the death toll for the titanic?
the death toll was 1517; the high number was due to the lack of lifeboats for all passengers
when and how was the wreckage of the titanic found?
the wreckage was found by Sonar in 1985 at a depth of 3.8km
where do oil spills occur?
oil spills most commonly occur in the water but can also occur on land (due to pipeline bursts)
describe the impacts of oil spills
the environmental impact can be devastating and clean-up can take months to years
oil penetrates bird feathers and mammal fur, reducing the ability to insulate
birds and animals are left vulnerable to temperature changes become less buoyant in water
