Ecology

1. AIR POLLUTION
Unwanted gases or related particles added in the air that affects life directly or
indirectly
KINDS: NOx, SOx, COx, O3, Smog, PAN, PAH, NH3, smoke, dust particles,
water vapors, pollens, spores etc
SOURCES: Transportation Industry
Power generation Waste disposal
Space heating (green house effects)
Pollens from non-indigenous wild plants
Spore from excess growth of fungus of solid wastes not properly
disposed off
NOX: NO, NO2 & NO3 produced from fertilizer industry, transportation and
wastewater disposal
i. NOx + O2 → NO3↓↓↓
ii. NOx + H2O → HNO3 (acid)
iii. NOx effectively enter stratosphere (natural & nitrogen based
fertilizer) as
NOx in stratosphere → nitric acid → destroy ozone
molecules
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2. But; NOx UV
→ NO + O
i. O + O2 → O3
ii. N + Cl → N Cl no ozone depleting
SOX: SO & SO2 produced from fertilizer industry, transportation
and wastewater disposal
i. SOx + O2 → SO4↓↓↓
ii. SOx adsorbs on particulate pollutants (dust particles & fly
ashes) come in contact with wet tissues (lung surface) or
moisture and turn into acid
SOx + H2O → H2SO4 (acid)
iii. Causes health hazards
iv. Corroding of metals used for construction
v. Cause deterioration of limestone used in buildings or statues
vi. Produce Acid Rain, which is damaging life on the ground
COX: CO & CO2 produced from industries, transportation, burning and
waste disposal
i. CO + O2 → CO2
ii. CO2 when high in contents cause suffocation
iii. CO2 is absorbed by the plants for photosynthesis
iv. CO2 is absorbed by surface water of water bodies to
produce carbonic acid; a weak acid that can cause slight
decrease in pH of water
O3 : produced from photochemical reaction during the
production of PAN (peroxy acetyle nitrate):
NOx + hydrocarbons −UV
−−−⇒ PAN + O3
i. O3 is secondary pollutant (more toxic than primary pollutants)
ii. Cause eye watering and respiratory distress in human and animals
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3. iii. Extremely toxic for plants (damages shoot, flowers and growing
fruits)
iv. O3 increases metabolic rate depleting the reserve food
PAN: Peroxy Acetyle Nitrate
i. PAN is secondary pollutant
ii. Cause eye watering and respiratory distress in human and animals
iii. Extremely toxic for plants (damages shoot, flowers and growing
fruits)
iv. PAN blocks “HILL REACTION” i.e. shutting down the
photosynthesis
PAH: Polycyclic Aromatic Hydrocarbons
i. PAH is secondary pollutant, produced through photochemical
reaction
ii. Cause eye watering and respiratory distress in human and animals
iii. Carcinogenic (producing cancer in living organisms)
SMOG: produced from photochemical reaction as:
Smoke (hydrocarbon) + fog (water vapors + dust or ash particles) → smog
i. it is a secondary pollutants
ii. toxic for human as well as plants
iii. decrease visibility on roads
iv. cause eye watering, irritation and respiratory distress
NH3: produced from various factories, waste water disposal, solid
wastes etc
i. Cause eye watering & respiratory distress
ii. Cause suffocation
iii. Toxic for plants and animal’s skin and fur
SMOKE: unburned carbon atoms from wood fire, coal, automobile,
factories etc
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4. i. Causes suffocation
ii. Smoking: causes lungs cancer risk 10 times higher as
compared to country man non-smokers
WATER VAPORS: produced from various sources
i. increased humidity cause suffocation, lung problems,
asthma etc
ii. promote fungal growth and other pathogen propagation
POLLENS:
i. cause allergies (skin, nasal passage, trachea, asthma)
among human
ii. affect other plant propagation/growth/survival
SPORES:
i. Fungal spores cause skin infection in human
ii. cause allergies (skin, nasal, trachea, asthma) among human
MTBE (Methyl tertiary butyl ethane)
Can enter water sources through leaking underground or above-ground gas
storage tanks and pipelines, as well as from gasoline spills
Effects: Some people have complained of symptoms such as nausea,
dizziness, light headedness, headaches, and nose and throat irritation after
breathing vapors from gas containing MTBE.
OZONE DEPLETING CHEMICALS
1. CFC (Chlorofluorocarbon): carbon + fluorine + chlorine made artificially
i. trichlorofluorocarbon CFC – 11 = CFCl3
ii. dichlorofluorocarbon CFC –12 = CF2Cl3
2. CFMs (chlofluoromethane) are fully hologenated (containing H atoms)
i. CFC –113, CFC –114, CFC –115 are non-water soluble, stable in the
air
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5. ii. HCFCs (hydrochlorofluorocarbon) are less stable in air & deplete
ozone 2-5 % as compared to CFCs
Methanotropic bacteria degrade HCFCs (not CFCs)
3. HFCs (hydrofluorocarbon): no chlorine; don’t destroy ozone
be substituted to CFCs & HCFCs if possible
4. Halons (fluorocarbons): contain bromine atoms that when released cause
ozone depletion.
e.g. Methyle bromide, methyle chloroform & carbon tetrachloride are
ozone depleting.
Natural causes:
i. HOx from water vapors, CH4, H2, NOx — destroy ozone
ii. NOx effectively enter stratosphere (natural & nitrogen based fertilizer)
as NOx in stratosphere → nitric acid → destroy ozone molecules
But; NOx
UV
→NO + O i. O + O2 → O3
ii. N + Cl → N Cl no ozone depleting
IMPACTS OF ENVIRONMENTAL POLLUTION
NOISE POLLUTION
(Unwanted sound dumped into the atmosphere)
Sources:
i. Industrial machines
ii. Aircrafts
iii. Motorways
iv. Crowed
v. Radio, TV & Musical instruments
Causes:
i & ii are producing disturbance to man and damage hearing
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6. iii, iv & v interfere human conversation and cause emotional and
behavioral stress
Units:
i. bel = log 10 I/I0
ii. decibel, db = 10 log 10 I/I0
where as I = sound intensity
I0 = reference level that produce sound pressure of 0.0002 microbar
(dynes/cm2
or energy about 10–16
watts)
The noise of 10, 20 and 100 db represent 10, 100 and 1010
times threshold intensity
of sound
The frequency 20 – 20,000 cps and intensity 0 – 120 db cause physical discomfort
Conversion: frequency 250 – 10,000 cps = 30 – 60 db
Jet aeroplan at takeoff is 160 db and the sound pressure is also very high
Loudness: units are sones
1 sone = 40 db at 1000 cps
2 sones = 40 db at 5000 cps
50 sones or above is too loud at any frequency
● 85 db (10 – 50 sones depending on frequency) is critical level of ear damage
● continuous noise is less damaging than sudden (sonic) noise
● it breaks property e.g. broken windows
● decibel meter at highway be installed and set at 82 db
Green belt: Plants are good absorbers and reduce noise by 10db
The plants should be shorter towards the noise and taller away from the source
The leaves of the plants not only absorb but also reflect noise.
Solution: i. Reduce noise as much as possible by using technology
ii. Zone the area around
iii. Green belt of farm and forest be developed
Positive points: Sound is necessary for the human existence in nature
(song birds)
(humans music)
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7. WATER POLLUTION
Undesirable changes in water bodies that harm living organisms as well as humans
directly or indirectly and deplete natural resources.
CONCEPT
1. Composition (what it is)
2. Source (where it is)
3. Fate (where it goes)
COMPOSITION
1. OXYGEN DEMANDING WASTES
Organic wastes increase BOD (amount of oxygen required by the organism to
carry out decomposition in particular lake/pond.
2. INFECTIOUS AGENTS
Bacteria, Viruses, Protozoan, Parasites (worms)
Cholera, Typhoid, Diphtheria etc_______ Human diseases
Chlorine___________ to kill them easily but
Protozoan (Giardia): Resistant to chlorine
Hepatitus viruses: Resistant to chlorine
Diarrhea, Cramps & others
All are linked with Human faces
3. PLANT NUTRIENTS
Fertilizers Phosphates:
Phosphorus is limiting nutrient in Freshwaters
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8. Nitrogen:
Limiting nutrient in marine water
Both increase plant (algae) growth (ALGAL BLOOM) eutrophication
4. ORGANIC CHEMICALS
a. Natural Petroleum or Coal
b. Synthetic organic compounds (SOCs) from Industries are most
toxic
Both are Biologically Magnified
5. INORGANIC CHEMICALS
Non-Carbon e.g.
i. Metals: bind with compounds like Protein molecules and cause
enzymatic interference in metabolism
ii. Acids: Acids rain from Industry discharge
6. SEDIMENT POLLUTION
by erosion
Sediments fill in the channels & reservoirs
damage gills of fish/shellfish
damage power generation
equipments
reduce light penetration for bottom plants
SOURCES
1. INDUSTRIAL
2. AGRICULTURAL
3. DOMESTIC WASTES
POINT SOURCE POLLUTANTS:
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9. Discharge pollutants at easily identified single location such as
discharge pipes
NON POINT POLLUTANTS:
Discharge pollutants from many locations such as Agricultural
pollutants (fertilizers drainage, pesticide runoff)
1. INDUSTRIAL WASTES
Industries contribute to all types of pollutants, mainly
A. Manufacturing B. Power generation
C. Mining & construction D. Food processing
A. Manufacturing:
Paints and pesticides by products (organic chemicals & heavy metals)
Toxic for all organism and man
Many billions of Kg of chemical wastes is produced
Chemical wastes are the largest product as toxic & hazardous wastes
B. Power Generation:
Heat & Radioactivity
Water vapors (steam)
C. Mining & Construction: (Sediments & Acids)
Mining discharge (Acidic) kill living organisms
Construction produce sediments
D. Food Processing:
Slaughter houses wastes like blood, intestine & viscera
Canning factories washing, processing & packing
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10. Animals & plant parts Meat, vegetable & fruit shops/markets
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11. 2. AGRICULTURAL WASTES:
Cultivation of crops (preparation of land)
Cultivation of Animals: animals produce 5-times more wastes as
compared to MAN
Crop: Erosion of land by removing plant cover
Sediments: agri. Runoff; draining of fertilizers & pesticides
Wastes are Infectious and oxygen demanding
i.e. disease causing agents, organic wastes, urea, & uric acid
3. DOMESTIC WASTES:
(house hold wastes)
i.e. like sewage & leakage from septic tank seeping to water bodies
contains oxygen demanding wastes & infectious agents
fertilizers used in house gardens & lawns
FATE OF POLLUTANTS
All pollutants go to the water bodies
Water has ability to dissolve & flow forward
Rivers & basins: Freshwater
Marine water
Freshwater: Rivers & streams
Drain water, filter or dilute rapidly
All three (industry, agriculture & domestic) are at the rivers from centuries because
i. used for transport
ii. fast moving carry wastes off & purify
River flood plains are exceptionally fertile due to nutrients in them from domestic
and agricultural where rivers overflow
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12. Everyone is downstream from someone
If they are living apart then purification process clean them but heavy
metals get attached with clay particles, settle down
Some get concentrated (biomagnified) and cause damages
Clean Water Act 1972: US must decrease river contaminations significantly
Man made alteration:
i. dams
ii. diversion of water
iii. channels alteration
iv. land developments
Has destroyed originality of water bodies
Lakes: get polluted easily as
i. slow water circulation
ii. dead-end i.e. pollutants nowhere to go
iii. less water amount/time
Lake Erie: polluted due to algal bloom
Control: Population of Zebra mussels increased, controlled was in
process
Ground water: polluted rapidly and remain polluted for very long time because
of:
water moves slowly i.e. few mm/day
aeration & dilution is slow
required centuries to recover
Ground water pollution:
i. deep well injection (unintentional)
ii. superficial percolation and underground leakage (unintentional)
Land fill, waste disposal pond spill, agricultural & land use
products (nitrates & pesticides)
iii. septic tanks leakage
Organic matter & gasoline
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13. UNINTENTIONAL INTENTIONAL
i. landfill deep well-injection
ii. waste disposal ponds
iii. spills
iv. agriculture & land use
Underground leakage
v. septic tanks
vi. buried wastes
vii. underground storage tanks
Over pumping
viii. Saltwater intrusion
MARINE WATER
1. Chemicals and sediments
Litter: coastal areas of ocean
Runoff: 44 %
Atmospheric: 33 % total: 77 %
rich in nutrients (breeding ground for larvae that are
sensitive to pollution
Fish catch (99%) 200 miles along the coast
Agricultural runoff:
sediments
plant nutrients
pathogens
Industry:
Synthetic organic chemicals
Toxic chemicals
City:
Oxygen demanding
e.g 85 % sewage discharge in Mediterranean is untreated
In 1992, 2500 beaches are ceased due to pollution
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14. 2. Oil and Litter
Oil spills: oils are toxic and most oil pollutions (46 %) are land based
i.e. 9.4 % Atmospheric
36.8 % city, industry, wastes & runoff
45 % oil transportation (1 ton oil is discharged from 1000
tons oil tanker) because oil tankers are continuously leaking as
oil slicks.
Litter: Plastic litter (wires, boards, fish nets, bags)
2 million sea birds &100,000 mammals die/year by eating OR
getting entangled in plastics.
25 % sea birds have plastic in their stomach
sea turtles and mammals die due to eating plastic bags
mistakenly as jelly fish
Plastic bands and rings encircles their bodies/neck leading to
death
Heavy metals in water
Metal toxicity or metal poisoning is the toxic effect of certain metals in certain
forms and doses on life. Some metals are toxic when they form poisonous soluble
compounds. ... Many metals, particularly heavy metals are toxic, but some heavy
metals are essential, and some, such as bismuth, have a low toxicity.
Impact on aquatic life
Heavy metals becomes very harmful to our health if found in our drinking water.
Severe effects include reduced growth and development, cancer, organ
damage, nervous system damage, and in extreme cases, death.
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15. PESTICIDES
Any substance or mixture of substances intended for preventing, destroying,
or mitigating any pest or intended for use as a plant regulator, defoliant, or
desiccant.
EPA Definition
Any substance or mixture of substances intended for preventing, destroying,
repelling, or mitigating any pest. Pests can be insects, mice and other
animals, unwanted plants (weeds), fungi, or microorganisms like bacteria and
viruses. Though often misunderstood to refer only to insecticides, the term
pesticide also applies to herbicides, fungicides, and various other substances
used to control pests. Under United States law, a pesticide is also any
substance or mixture of substances intended for use as a plant regulator,
defoliant, or desiccant.
PEST: Any species of living organism that:
i. compete for food with us
ii. invade farms, lawns and gardens
iii. destroy wood in the houses
iv. simple nuisance
WHY WE USE PESTICIDES:
As human population increased
Need for more agriculture increased
Protection of crops increased
Use of chemicals started
CATAGORIES OF PESTICIDES
1. Insecticides that kills insects
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16. 2. Herbicides that kills weeds
3. Fungicides that kill fungus
4. Nematocides that kill nematodes
5. Rodenticides that kill rats & mouse
6. Acaracides (miticides that kills mites and ticks)
7. Molluscicides
8. Antimicrobials / biocides
Ist Generation Pesticides (Natural)
Historically used pesticides that were inorganic compounds (Minerals) Known
as Ist generation pesticides.
Sulfur was in use 500 BC
Toxic compounds of Arsenic, lead and mercury were used but it was
abandoned by 1920s because of increased human poisoning
In 1600s, micro sulfate extracted from tobacco leaves was used.
In mid 1800s two natural pesticides came into use:
a. Pyrethrum--- obtained from head of chrysanthemum flowers
b. Rotenone--- from roots of tropical legumes
New chemicals extracted from plants were used to:
i. repel or kill insects in their households, yards, gardens
ii. save money
iii. reduce potential health hazards associated with chemicals
2nd
Generation Pesticides:
DDT, (dichlorodiphenyletrichloroethane) synthesized in 1873 since in
use from 1874
It became the most popular 2nd
generation insecticide
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17. Paul Muller was awarded Noble Prize as he discovered DDT an
excellent insecticide
- Since 1950 pesticide use increased 50 folds and today pesticides
are 10 times more toxic than pesticides of 1950.
According to one estimate
- 2.5 million tons of pesticides are used per year
- 75 % of that is used in developed countries
In US about
630 different biologically active ingredients and
1,820 different biologically inactive ingredients are mixed to
produce about 25,000 various pesticides
- 25 % pesticides are used for ridding/elimination of pest from houses,
garden, lawns, parks, playing fields, swimming pools and golf
courses
- US, EPA had indicated 10 times more insecticides are used in
lawns/hectare as compared to cropland.
- And 84 % houses use pesticides as pest strips (Pest strip products
containing the ingredient dichlorvos (also called 2,2-dichlorovinyl demethyl
phosphate or DDVP) are available for sale to consumers and pest control
professionals for a wide variety of uses. ... Dichlorvos is an organophosphate
pesticide), bug bombs (total release foggers, aerosol propellents), flea collars
(A flea collar is a device used to protect dogs and cats from fleas and ticks),
pet shampoos, and weed killer
- 250,000 people become ill because of these pesticides and become
responsible for the death of children’s under age 5.
Third generation pesticides
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18. - Insect pheromones
- Insect growth regulators
These disrupt the normal activity of the endocrine or hormone system of
insects, affecting the development, reproduction, or metamorphosis of the
target insect
–Chitin synthesis inhibitors
This target exoskeleton
– Juvenile hormones
Mimic hormones / insect remains in juvenile stage
– Bacillus thuringiensis
Toxins produced following ingestion
WHY PESTICIDES ARE USED
1. They save human lives: DDT, other chlorinated hydrocarbons and
organophosphates have saved 7 millions deaths since 1945 by
preventing:
i. Malaria (mosquitoes)
ii. Bubonic plague (rat fleas)
iv. Typhus (body lice and fleas)
v. Sleeping sickness (tsetse flies)
2. They increase food supply and lower food cost:
55 % of world’s food gets lost to pests
as before 35 %
after 20 %
In US about 37 % foods is lost to pests before & after harvest
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19. As 13 % to insects
12 % to plant pathogens
12 % to weeds
and about 65 million / year is lost with pests. With these losses:
- the price may rise
- the quality may decrease (worse quality my be available)
3. They work faster & better than alternatives:
Pesticide can
i. control most pests quickly at reasonable cost
ii. have long shelf life
iii. are easily shipped & applied
iv. are safe when used properly
If resistance appears:
- stronger doses can be applied
- switch to another pesticide is possible
4. Health risk is insignificant when used properly:
American Council on Science & Health (ACSH) reports that these
pesticides when used properly are more beneficial than damages
5. Newer pesticides are safer & more effective:
Greater use is being made of
i. Botanicals
ii. Micro botanicals
- Derived originally from plants that are safer and less demanding
from nature
- Genetic Engineering is also producing:
i. pest resistant crops
ii. genetically altered crops that produce pesticides
6. New pesticides are used at fewer rates:
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20. Applications per hectare for new pesticides are 1/100 times to the
older
7. Future pesticides:
that may
i. kill only the target pests
ii. harm no other species
iii. disappear/breakdown into harmless after use
iv. not cause genetic resistance
v. be more cost effective than doing nothing
- No known natural/synthetic pesticide chemical meets all or even most
of the above criteria
- But the advantages outweigh disadvantage
DISADVANTAGES OF PESTICIDES
1. Cause genetic resistance:
- resistant insects breed rapidly
- within 5-10 years they develop immunity to pesticide
- the same pests comeback more strongly
Since 1945, 1000 major pest species of insects, mites, weeds, plant
diseases and rodents have developed genetic resistance. About 17 insects
are resistant to all major classes of insecticides and fungal diseases are
immune to most of fungicides
DDT is now abandoned for agricultural use in 86 countries but still used for
mosquito control in developing countries
2. Kill natural pests and create new pests:
i. broad-spectrum insecticide kill natural predators & parasite e.g. wolf
spider, wasps, predatory beetles and other natural enemies
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21. rapidly reproducing pests can rebound and get lager within
days/weeks
ii. new pest (secondary pest) become major pest i.e. 100 of the 300
most destructive pests in US are secondary pests
iii. in Europe red mite became an important pest of apple tree after the
use of insecticide
3. Pesticide Treadmill:
After genetic resistance the pesticide sale representative
recommend more frequent application
i. larger doses
ii. new chemicals are used to keep resistance species under control
- This creates pesticide treadmill
- Genetic altered crops can put farmers on a similar genetic
treadmill
CHLORINE
Today we largely depend upon CHLORINE as Chlorine Coating
Compounds.
About 11,000 chlorine coating compounds that produced are:
i. persistent
ii. accumulate in the body fat
iii. harmful to human health
The largest uses of chlorine are in the synthesis of:
i. Plastics (mostly PVCs)
ii. Solvents
iii. Paper & pulp bleaching
Altogether they account for 80 % chlorine
Recommendations are:
i. Substitute should be used
ii. Non-chlorine plastics & other products should replace PVCs
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22. iii. PVCs incineration should be prohibited
In 1993 American Public Health Association (APHA) approved that Industries
should NOT use Chlorine except:
i. producing some pharmaceuticals
ii. disinfecting public water supplies
About 80 % chlorinated organic chemicals should be replaced over a decade
by:
i. Soap & water
ii. Steam cleaning
iii. Citrus based solvents
iv. Physical cleaning (pressurized solution of water & baking soda)
Wood & pulp bleaching with chlorine be replaced with less harmful processes
that rely on oxygen, ozone & hydrogen peroxide.
In 1990s German produced totally chlorine free paper with 30 % less price.
DIOXINS
Dioxins are formed as a result of combustion processes such as waste
incineration (commercial or municipal) or from burning fuels (like wood, coal
or oil).
Dioxins can also be formed when household trash is burned or from events
like forest fires.* Incineration of municipal & medical wastes, Coal-fired power
plants & metal melting plants, Wood pulp & paper mills, Sludge from waste
water treatment plants.
Dioxins, in their purest form, look like crystals or a colorless solid.
Most dioxins and furans are not man-made or produced intentionally, but
are created when other chemicals or products are made. Of all of the dioxins
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23. and furans, one, 2,3,7,8-tetrachloro-p-dibenzo-dioxin (2,3,7,8 TCDD) is
considered the most toxic as it remain in the environment for decades in soil
and human fat tissues
HUMAN acquire 90 % of dioxins from fatty meat eating & contaminated
animal products such as fats
Harmful effects on humans
A. In year 2000 a 6 year study of 100 scientists spending 4 million USD
reported:
i. TCDD is human carcinogen
ii. Lower doses of dioxins causes disruption of reproductive, endocrine &
immune systems
iii. Very small doses of dioxins causes serious damage to wildlife species
B. In 1988, German scientists concluded that 12 % cancer in industrialized
countries is due to dioxins and has produced 120,000 cases each year in US.
According to EPA report on average 365 deaths per year (1 per day) in US
are due to dioxins.
C. In year 2000 study reported by Kyle Steenland, a scientist of National
Institute for Occupational Study (NIOC) found
i. people exposure to dioxins increase the risk of death by 60 % due to
cancer
ii. no significant risk of cancer when exposed to very lower doses
While industrialists says that the results are overestimated
But we should reduce dioxins emission as a precautionary strategy
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24. Polychlorinated biphenyl (PCBs)
PCBs are of 209 different types:
i. Insoluble in water
ii. Soluble in fats
iii. Resistant to biological & chemical degradation.
They enter in the food chain; accumulate in the tissue as Bioaccumulants.
High doses of PCBs produce:
i. liver & kidney damage
ii. Gastric disorder
iii. Birth defects
iv. Skin lesions
v. Hormonal changes
vi. Tumors
vii. Sexual abnormalities
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25. 25

26. 26

27. RADIOACTIVE POLLUTION
RADIOACTIVE: Material-emitting radiations
Types of Radiation:
IONIZING RADIATION: Radiation able to remove electron from one atom and
attach them to another thereby producing positive or negative ion pairs are ionizing
radiation and material is called RADIOISOTOPES or RADIONULIDES
Nonionizing radiation
Non-ionizing radiation does not carry enough energy to break molecular
bonds and ionize atoms. Example of non-ionizing are ELF and
RF radiation.
Radioactive Decay: Radioactive atoms/Radioisotopes/Radionuclides produce
radiations (disintegrates) as radioactive decay.
Effects: Inside human body it damages the
Atoms
Molecules
Cells particularly rapidly dividing cells e.g. fetus, kids and
Adults: bone marrow, red cells, lining of digestive tract,
cells of thyroids, stomach, testes, ovaries, lungs & breasts
SOURCES:
1. Natural rocks as Uranium, Thorium, and Potassium-40
e.g. Uranium → Radon gas
2. Cosmic rays: from space on earth. Increase intensity as we ascend.
1000 hrs/year of flight means one ‘REM’ absorption of radiation while at
ground it is 1/20th
– 1/10th
to this dose.
3. Uranium enrichment plants: where uranium is purified and processed
4. Nuclear reactors: where nuclear weapons are made
5. Nuclear power plants: where power is generated
6. Nuclear medicine: where treatments are given by exposing to radiations
UNITS:
27

28. 1. Curie: after Marie Curie who discovered Radium-226
1 cu = 37 billion radioactive discharge/sec
2. Becquerel: 1 decay or disintegration/sec = 1 Bq
3. Rad: (radiation absorbed dose) is measure of energy
1 Rad = 0.01 J/kg
Man exposed to 3000 rads will die within hours
400 – 3000 rads will die within weeks
250 rads half will die & half will die within months
due to the damage in bone marrow, digestive tract and blood vessels
100 rads will burn skin
5 rads will cause vomiting and diarrhea
4. Rem: (radio equivalent man) measures the relative impact of absorption
unit of radiation dosage (such as from X rays) applied to humans.
Derived
1 rem = effects produced by 1 rad of x-rays
5. Sievert: The sievert (symbol: Sv) is a derived unit of ionizing radiation
dose in the International System of Units (SI) and is a measure of the
health effect of low levels of ionizing radiation on the human body. ...
One sievert equals 100 rem.
Types of Radiations :
1. α- rays: part of helium atom and positively charged particles, travel few cm in air
and can be stopped by sheet of paper but transfer huge ionization when
stopped locally by the object.
2. β-rays: high-speed electrons can travel few feet in air and few cm in tissue. They
cause ionization in the tissues.
3. γ-rays: electromagnetic radiations (ionizing), penetrate deep inside the tissue
4. Neutrons: Charge less, induce radioactivity and cause 5-10 times more radiations
than γ-rays
5. X rays are similar to γ-rays but do not cause radioactivity and are used in
medicine
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29. 6. Cosmic rays: radiation from the outer space, they are mixture of corpuscular and
electromagnetic radiations. There intensity is low in biosphere.
As a Survey Americans are exposed to 200-360 rem/year.
80 % are ionizing background radiations
20 % are man made i.e. from nuclear weapon explosion, nuclear wastes, and
release from power plants, nuclear medicine, x rays, computers, TV & other
machines.
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30. THERMAL POLLUTION
Government officials and top climate scientists will meet in Berlin from April 7-12 to review the
29-page draft that also estimates the needed shift to low-carbon energies would cost between two
and six percent of world output by 2050.
It says nations will have to impose drastic curbs on their still rising greenhouse gas emissions to
keep a promise made by almost 200 countries in 2010 to limit global warming to less than 2
degrees Celsius (3.6 Fahrenheit) over pre-industrial times.
Temperatures have already risen by about 0.8 C (1.4F) since 1900 and are set to breach the 2 C
ceiling on current trends in coming decades, U.N. reports show.
"The window is shutting very rapidly on the 2 degrees target," said Johan Rockstrom, head of the
Stockholm Resilience Centre, and an expert on risks to the planet from heatwaves, floods, droughts
and rising seas.
"The debate is drifting to 'maybe we can adapt to 2 degrees, maybe 3 or even 4'," Rockstrom, who
was not among authors of the draft, told Reuters.
World's Top Scientists Issue Climate Warning Play video
Such rises would sharply raise risks to food and water supplies and could trigger irreversible
damage, such as a meltdown of Greenland's ice, according to U.N. reports.
The draft, seen by Reuters, outlines ways to cut emissions and boost low-carbon energy, which
includes renewables such as wind, hydro- and solar power, nuclear power and "clean" fossil fuels,
whose carbon emissions are captured and buried.
It said such low-carbon sources accounted for 17 percent of the world's total energy supplies in
2010 and their share would have to triple - to 51 percent - or quadruple by 2050, according to most
scenarios reviewed.
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31. The new draft shows that getting on track to meet the 2C goal would mean limiting greenhouse gas
emissions to between 30 and 50 billion tonnes in 2030, a radical shift after a surge to 49 billion
tonnes in 2010 from 38 billion in 1990.
The shift would reduce economic output by between 2-6 percent by 2050, because of the costs of
building a cleaner energy system based on low-carbon energies that are more expensive than
abundant coal, the IPCC said. Capturing carbon dioxide is also expensive, it added.
China and the United States are the top emitters.
One option is to let temperatures overshoot the 2C target while developing technology to cool the
planet by extracting greenhouse gases from the atmosphere, the draft says. The draft that would add
to risks of warming and push up costs.
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32. 32

33. (Unwanted heat dumped in the environment)
Sources:
1. Industries
2. Automobiles
3. Thermal power plants
4. Nuclear power plants
5. Nuclear test fires/blasts
Causes:
1. Increase in local temperature (speared of diseases)
2. Increase in global temperature
i. Agriculture:
- Shift in flood grow areas
- Changes in crop yield
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34. - Increased irrigation demand
- Increase in pest spp, diseases & weed areas
ii. Biodiversity:
- Extinction of some plants & animal species
- Loss of habitats
- Disruption of aquatic life
-
iii. Forests:
- Change in forest composition
- Disappearance of some species
- In creased fire
- Loss of wildlife habitat & species
iv. Human population:
- Increased deaths
- More environmental refuges
- Increased migration
-
v. Human health:
- Increased deaths from heat & diseases
- Disruption of food & matter
- Spread of tropical diseases to temperate areas
- Increased respiratory diseases
- Increased water pollution from coastal flooding
vi. Sea levels & coastal areas:
- Rising sea levels
- Flooding of low lying islands & coastal cities
- Flooding of coastal estuaries, wetlands & coral reefs
- Beach erosion
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35. - Disruption of coastal fisheries
- Contamination of coastal aquifiber with salt
vii. Water resources:
- Change in water supply
- Decreased water quality
- Increased drought
- Increased flooding
viii. Weather extremes:
- Prolonged heat wave & droughts
- Increased flooding
- Hurricanes, typhoons, tornados & violent storms
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