Transcript

THE GREAT SMOG OF 1952

HISTORICAL AND CURRENT PERSPECTIVES

Presentation Highlights
◦ The problem of Air Pollution
◦ Notoriety of the Great Smog of 1952
◦ Vulnerable Groups
◦ Risk Analysis
◦ Strategies of Risk Analysis during the great smog event
◦ Parallels with the Jamaican environment
◦ Questions

The Problem of Air Pollution
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Three million people die each year from the effects of air pollution alone!!
(WHO)

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What is Air Pollution?
◦ The presence or introduction of a substance which has harmful or poisonous effects
 Example: diesel exhaust, nitrogen oxide

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What is smog?
◦ Mixture of fog and air contaminants
◦ A yellowish haze caused by a mixture of atmospheric pollutants and it consists mainly of
fine particles and ozone.

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Major factors contributing to smog formation
◦ Main sources of these pollutants are industrial processes usually involving burning and
heating.

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Contribution to Global Warming
◦ Traps greenhouse gases in the atmosphere
◦ Depletes ozone layer

Notoriety of the Great Smog of
1952
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History of smog in London
 London has long been famous for its filthy air
 Grey skies not always due to fog but to smog
 Several smog disasters between the late nineteenth to mid twentieth century

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The Great smog of 1952
 the climax of a long and dirty history.
 the “bleakest” day in European history
 described as worse than the 1866 cholera outbreak.
 visibility dropped below 500 meters continuously for 114 hours; 50
meters for 48 hours.
 visibility remained below 10 for almost 48 hours at Heathrow Airport

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Morbidity and Mortality rates
 death toll approximately 10,000
 worst case of mortality and morbidity due to smog

Vulnerable Groups
The Elderly
 Persons with Respiratory Problems
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Risk Analysis
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Risk analysis involves:
◦ Risk Assessment which is a four step process including:
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Hazard identification
Exposure assessment
Dose response assessment
Risk characterization

◦ Risk Management
 The process of weighing policy alternatives and selecting the most appropriate
regulatory action based on the results of risk assessment, social and political
concerns

◦ Risk Communication
 The process of making risk management and risk assessment comprehensible
to all relevant stakeholders and the general public
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The importance of risk analysis
◦ To identify, characterize, minimize or eliminate hazards that threaten the quality
of life

Strategies of Risk Analysis during the great
smog event
(Risk Assessment)
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Strategies employed:
◦ Hazard Identification
 The ubiquitous burning of coal identified as a major risk factor
 The smoke resulting from excessive burning of coal identified as a
major health hazard
 Recognition that excessive smog caused by air pollution with smoke
caused respiratory problems which increased mortality rates.

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Problems with the strategies of risk assessment
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Timing (information was slow in coming)
Lack of scientific evidence to validate claims
No proper exposure assessment.
Lack of scientific studies to properly conduct dose response
assessment.

Strategies of Risk Analysis during the great smog event
(Risk Management)

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Strategies employed
 Calls from various groups to deal with the hazard
 Committees set up to address the risk
 Possible policies to deal with the hazard discussed

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Problems with the strategies
 Ineffective committees
 Lack of political will to fix the problem

Strategies of Risk Analysis during the great smog event
(Risk Communication)
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Strategies employed
◦ Communication of the extent of the hazard by various groups to government:
 Example: discussions in parliament

◦ Commissioning of an inquiry to research and communicate the health and
financial implications of the hazard
◦ Passing of legislative acts to:
 Increase awareness of the risk and risk factors
 Curtail the problem of air pollution
 The 1956 Clean Air Act - mandating establishment of smokeless zones
and domestic use of heaters fueled by gas, oil, smokeless coal or electricity
instead of traditional fires.
 The 1968 Act - mandating the use of tall chimneys for industries burning
coal liquid or gaseous fuels.

Parallels with the Jamaican
Environment
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Pollution in Jamaica
◦ Pollution index of 78.02 on a scale of 0 – 137
◦ Air pollution considered high

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Agencies and Organizations
◦ Ministry of Health
 Regulatory body that governs health issues including pollution

◦ National Environment and Planning Agency
 Major agency that grants approval for development projects
 Strict set of conditions that must be adhered to
 Periodic and random site visits to ensure compliance

Thank You!!