Lecture 15 & 16
 Water, Air, Noise, Radioactive Pollution
 Toxicity: Bioaccumulation, Biomagnification,
Eutrophication, LD50
Pollutants and Pollution
Pollutants:
The matters in any sphere of environment that causes
danger to humans, vegetation and abiotic environment
Pollution:
 Presence of one or more pollutants in any sphere
 such quantities & such duration
 that may tend to be injurious to human, plant or animal
life or properties
 or unreasonably interfere with enjoyment of life and
conducting business
Air Pollution
Natural Sources
 Volcanoes, forest fires, ocean spray, biologic sources,
wetlands, decomposition
Anthropogenic sources
 Burning fossil fuel
Transportation, Power plant, Industry, etc.
 Agricultural practices
Cultivation & cropping, livestock farming
 Cooking with firewood
 Waste disposal
Major Air Pollutants
PM
Gaseous:
SOx
NOx
CO2, CO, CH4
H2S
CFCs
HC
Effects of Air Pollution
 Respiratory diseases
 Cough
 Skin
 Kidney and lungs
 Cancer
Types of water pollutants
 Oxygen demanding waste
 Disease-causing agents
 Synthetic organic compounds
 Plant nutrients
 Inorganic chemicals and minerals
 Oil
 Sediments
 Radioactive wastes
 Thermal discharge (heat)
Sources of water pollution
 sewage, fertilizers and pesticide
 Industrial effluent
 Dumping waste (domestic)
 Dumping from ships
 hot water from power plant
 waste treatment plants
 Atmospheric contaminants
Sources of water pollution
 Oil spill
 Washing
 Sea water intrusion
 Natural weathering
 Mining
 Run-off
 Acid rain
Effects of water pollution
 Water borne diseases (Typhoid,
Cholera, Dysentery, Jaundice)
 imbalance aquatic ecosystems
 Damage biological diversity
 deforestation from acid rain
 Eutrophication
 Migration
Noise Pollution
 Undesired sound that disturbs normal way of life
interfering with working efficiency, enjoyment and prayer
 Music for one noise for other
Sources of Noise
 Transportation (Air, road, water)
 Construction sites
 Catering and night life
 Animals
 loud music
 Generators
 Lawn care equipment
 Explosion
Effects of Noise Pollution
1. Physical
 Respiratory agitation, racing pulse, high blood pressure,
headaches, hearing loss, even heart attacks
2. Psychological
 Noise can cause stress, fatigue, depression, anxiety
3. Sleep and behavioral disorders
4. Memory and concentration
Radioactive pollution
 Presence of radioactive substances on surfaces or within
solids, liquids or gases including the human body where
their presence is unintended or undesirable
Sources
 Nuclear explosions and testing of nuclear weapons
 nuclear weapon production and neutralizing
 mining of radioactive ores
 handling and disposal of radioactive waste
 accidents at nuclear power plants
Effects of Radioactive Pollution
 Sudden death
 Cancer
 Cardiovascular diseases
 Skin
 Genetic issues
 nausea, vomiting, hair loss, diarrhea,
hemorrhage, central nervous system damage,
 Soil toxicity and nutrient loss
 Damage ecosystem
LD50
LC50 Vs LD50
 In between LC50 and LD50, certainly LD50 will be used to
represent the drugs /chemical which will kill 50% population
of animals in single oral administration
 whereas LC50 will be used to show the concentration of a
chemical in air exposed for 4hr to kill 50%of population
during observation (generally 14 days)
ED50
 Amount or dose of a chemical that causes an observable or
undesirable effect or desired symptom in 50 percent of the
test population (test organisms/specimens)
Eutrophication
 Excessive richness of nutrients in a lake or other body of
water, frequently due to run-off from the land, which causes
a dense growth of plant life.
 Why eutrophication?
Bioaccumulation & Biomagnification
Biaccumulation
 Bioaccumulation is the process by which toxins enter the food
web by building up in individual organisms
 When DDT enters aquatic bodies, it gets build up in the body
of fishes and this is known as bioaccumulation
Biomagnification
 The process by which toxins are passed from one trophic
level to the next and thereby increase in concentration
 When fishes are eaten by animals of higher trophic levels
(humans), concentration of DDT is increased at each
successive trophic level & this is known as biomagnification
Environmental Science Discipline
1st year 1st Term
Course Tile: Introduction to Environmental Science
Class test
Full marks 15; Time: 30 minutes
1. Define environment and Environmental Science.
2. Demonstrate the importance of studying Environmental Science.
3. Do you think that Environmental Science is a multidisciplinary
subject? Justify.