1. A334 P01 Revision
2 Types pollution source (Origin)
Single, identifiable ‘Point Sources’, (can be Dispersed and often difficult to identify
traced, easier to control) source
Of emission, ‘Nonpoint Sources’
- Smokestack of a power plant - Runoff of fertilizers, oil and pesticides into
- Drainpipe of a canning factory bodies of water including streams, lakes and
- Municipal sewage treatment plant groundwater
discharges - Pesticides sprayed into the air or blown by
the wind into the atmosphere
- Exhaust smoke from expressway
- Exhaust pipe of an automobile* - Exhaust smoke from expressway
**Both are similar cases, however exhaust smoke from expressway is likely to fall nonpoint
sources as it comprise of many various sources; result in accumulative effect of smoke from
expressway.
2 Types of pollutants
Primary, pollutant emitted directly from Secondary, primary pollutants react with
direct/original source. other compounds in the atmosphere
(involved chemical reactions)
• Carbon monoxide (CO) • Nitrogen dioxide NO2
• Oxides of nitrogen (NOx, NO) • Ozone (O3), which is formed when
• Sulfur oxides (SOx) hydrocarbons (HC) and nitrogen
• Volatile organic compounds (VOCs) oxides (NOx) combine in the
• Particulate matter (dust, ash, salt presence of sunlight
particles) • NO2, which is formed as NO
combines with oxygen in the air
• Acid rain (Sulfuric acid H2SO4), which
is formed when sulfur dioxide or
nitrogen oxides react with water.
Emission-transport-process
Pollution Problem Emission Transport Receptor
Donora Death Zinc smelter and steel Air People breath in smog
Smog mill
Minamata Disease Mercury discharges Minamata Bay People in Japan
from factory (untreated) (water) drinking mercury
contaminated water.
Arsenic Pollution Arsenic (from soil) Soil and Ground People living in
water Bangladesh
Nigerian Hazardous Hazardous waste found Water bodies People and animals
Waste Pollution in Koko Port living in Nigeria
Prevention of Pollution
Methodology Examples
Establishment of Government Setting up National Environment Agency (NEA) to
Agency regulate pollution control and monitoring
Establishment of legislations Environmental Protection and Management Act,
established, controls are stringently enforced on
emission standard
Public Education Campaign to educate public

2. Regular environmental monitoring Monitor of PSI reading
Pollution Control Department established in Singapore
- Responsible for ensuring that environmental factors are incorporated into land use
planning, development and building control of new developments, air and water
pollution control, and hazardous substances and toxic industrial wastes control
- Monitors the ambient air quality and the quality of water bodies in Singapore.
- Responsible for the formulation and implementation of joint programmes on
transboundary pollution with the neighbouring countries.
Coverage of aspects of environment under Pollution Control Department
- Land use planning and development
- Air and water
- Hazardous substances and toxic industrial wastes control