Topic 5.3

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Pollution Management Strategies
3 Step Process
1. Change human activity which causes pollution
2. Reduce the amount of pollutants released into the environment
3. Clean up pollutants from the environment after they have been
released
Change the human activity that generates the
pollutant in the first place
• this is the most proactive/preventative strategy because the pollutant
is not created (or less of it is created) in the first place
• tends to be difficult to achieve because it’s necessary to change the
behavior of people, businesses, and/or governments
Minimize the amount of the pollutant released
into the environment
• this is the next most proactive/preventative strategy because the
pollutant is controlled at the place where it is released
• this strategy is frequently adopted by government agencies that
regulate industries because monitoring is easiest at the place of
emission
• this strategy fails to fully address the problem because the pollutant is
still being produced
Clean up the pollutant and the affected areas
after the pollutant has been released
• this is a reactive strategy and tends to be very expensive; it also
usually takes a very long time to implement
• Sometimes it may not be scientifically possible
• this strategy does not solve the problem
https://www.youtube.com/watch?v=fddYApFEWfY
Human factors that affect the approaches to
pollution management
• Cultural factors: if society adopts an 'out of sight, out of mind'
approaches then individuals would be more likely to dispose pollution
in a more hazardous way.
• Political: weak regulation and lack of enforcement in LEDC’s; strong
corporate involvement and lobbying in policy decisions in MEDC’s
• Economic: pollution can be promoted if the environment is seen as a
free resources; the cost of reducing or cleaning pollution would
reduce the likelihoods of solving the pollution problem
DDT
• DDT was developed as the first of the modern synthetic insecticides in
the 1940s. It was initially used with great effect to combat malaria,
typhus, and the other insect-borne human diseases among both
military and civilian populations and for insect control in crop and
livestock production, institutions, homes, and gardens.
DDT Facts
• quick success led to the development of resistance by many insect pest
species.
• persistent organic pollutants that is extremely hydrophilic and strongly
absorbed by soil
• has a soil half-life range from 22 days to 30 years
• banned after the publishing of Silent Spring by Rachel Carson
• Stockholm Convention banned DDT internationally for agriculture but not
for disease control
Silent Spring
• Rachel Carson highlighted the dangers of DDT in her groundbreaking 1962
book Silent Spring. Carson used DDT to tell the broader story of the
disastrous consequences of the overuse of insecticides, and raised enough
concern from her testimony before Congress to trigger the establishment
of the Environmental Protection Agency (EPA).
• Her work attracted outrage from the pesticide industry and others. Her
credibility as a scientist was attacked, and she was derided as “hysterical,”
despite her fact-based assertions and calm and scholarly demeanor.
Following the hearings, President Kennedy convened a committee to
review the evidence Carson presented. The committee's review completely
vindicating her findings.
Advantages of DDT
• Broad spectrum
• Non-toxic
• Highly persistent giving long lasting effect
• Safe if used properly
• Alternatives are not as effective
• DDT significantly reduce malaria death e.g. in Ecuador between 1993-1995, the
increase use of DDT= 61% reduction in malaria
• 250 million/year of Malaria infections
• Banning of DDT equal to increase in malaria and resurgence of mosquitoes
Disadvantages of DDT
• Lead to premature birth, low birth weight and abnormal mental
development of infants
• Alternatives methods of pest control exist
• Would affect other wildlife
• Significant ecological effects
• The effects of accumulation in human tissue are not fully known
• Loss and degradation of soil
• https://www.youtube.com/watch?v=Ipbc-6IvMQI DDT
• https://www.youtube.com/watch?v=kHwqandRTSQ Stossel
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