Chemistry and Water Pollution
Mikelle Sinnette (00033871)
Nadia Richards (00054966)
Genevieve Sebastien (00029379)
Shamila Harricharan (00051290)
Gillian P- Gardiner (00025843)
CRN 86946 CHEM 092
Environmental degradation in Trinidad and Tobago
has historical roots that are not too dissimilar from
those in the rest of the world, attributed largely to
economic growth and the development and growth
of human population. The problem of water pollution is
widespread, and caused mainly by:
• human activities resulting from littering,
• unsettled quarry wash,
• industrial plant and factory waste,
• over use of fertilizers and pesticides,
• bush fires, slash and burn and deforestation,
• waste oils and untreated or poorly treated sewerage.
Chemical Properties Of Water
Water is bonded covalently by two
hydrogen’s (H) and one oxygen (O)
This diagram represents:
The covalent bonds.
Pink dots (O)electrons
Yellow dots (H)electrons.
What is Water Pollution?
• Water Pollution is the contamination of
water. This generally refers to the adverse
changes in water quality, usually as a result
of human activities.
• The substances that cause water pollution
are called pollutants.
Some examples of Pollutants
• Factories & Refineries (Oil and industrial waste)
• Agriculture (Pesticides, fertilizers, Eutrophication)
• Human Sewage (Failing septic tanks, pit latrines)
• Marine Dumping
• Mining (sediment run off)
• Agriculture (Pesticides, herbicides and fertilizers)
• Household chemicals (soap, oven cleaners etc.)
• Dumping (non-biodegradable (plastic bottles)
Types of water pollution
Water pollution coming
from a single point, such as
a sewage-outflow pipe.
From factories, industries,
Types of water pollution ‘Cont.’
Non-point Source Pollution
Is associated with storm water
• A widely spread source of
pollution that can’t be tied to
a specific point of origin is
called nonpoint source
• Example: Runoff from a farm
field, a street, or a
Types of water pollution ‘Cont.’
• Surface Water Pollution: For example, a spill
from an oil tanker creates an oil slick that can
affect a vast area of the ocean.
• Ground Water Pollution: Water stored
underground in aquifers (is an underground layer
of water bearing permeable rock, gravel sand
slit)is known as groundwater.
Other forms of water pollution
• Thermal Pollution caused by heat from power
plants and factories raising the temperature it
reduces oxygen levels in the water thus reducing
• Sediments (fine-grained powders) The extra
sediment can block the gills of fish, effectively
suffocating them effecting the supply of fish.
Three major sources of water pollution
*Industrial waste *Human waste *Chemical runoff.
Industrial Waste & Water Pollution
Industries cause huge water pollution with their
activities. These come mainly from:
Mercury (Hg hydrargyrum) commonly known as
Asbestos Chrysotile (White), Mg3(Si2O5)(OH)4
Amosite/Grunerite (Brown) Fe7Si8O22(OH)2
Crocidolite (Blue) Na2(Fe,Mg)5Si8O22(OH)2
Human Waste & Water Pollution
• Sewage is the term used for
wastewater that often contains
faeces, urine and laundry waste
• Untreated sewage can often
carry harmful viruses and
bacteria into the environment
causing health problems such
as diarrhea and cholera.
• Littering & Dumping
Chemical run off and Water Pollution
Chemical pollution, since the sources are so varied, can be
more difficult to remove (non- biodegradable) and
neutralize. There are numerous types of chemicals that
Atmosphere and Water pollution
• Acid rain is rain or
another form of
precipitation that is
more acidic than
• Acid rain can affect
fish, harm trees, and
eat away the stone of
buildings and statues.
• Oil spills cause a very localized problem but can be
catastrophic to local marine wildlife such as fish,
birds and sea otters.
• Oil cannot dissolve in water and forms a thick
sludge in the water. This suffocates fish, gets
caught in the feathers of marine birds stopping
them from flying and blocks light from
photosynthetic aquatic plants.
• Nuclear waste is produced
from industrial, medical and
scientific processes that use
radioactive material. Nuclear
waste can have detrimental
effects on marine habitats.
Effects of Water Pollution
• DEATH OF AQUATIC (WATER) ANIMALS
• DISRUPTION OF FOOD CHAINS
• DISEASES (hepatitis, cholera, cancers & death)
• DISRUPTION OF ECO-SYSTEM (algae blooms)
• Together, sewage and fertilizers can cause a massive
increase in the growth of algae or plankton that
overwhelms huge areas of oceans, lakes, or rivers. This is
known as a harmful algal bloom (also known as an HAB or
red tide, because it can turn the water red). It is harmful
because it removes oxygen from the water that kills other
forms of life, leading to what is known as a dead zone.
How can we stop Water Pollution?
• Laws- Environmental and conservation laws for
industries (fishing, boating, chemical).
• Education- promoting programs e.g. involving
recycling and proper disposal in schools and in the
• Economics- for example clean up
plans and programs.
• Dispose of rubbish correctly. “Think before you toss!”
• Use water wisely.
• Do not throw chemicals, oils, paints and medicines
down the sink drain, or the toilet.
• Buy more eco-friendly products.
• Plant a lot of trees and flowers around your home.
• According to 2004 figures from the World Health Organization,
some 1.1 billion people (16 percent of the world's population)
don't have access to safe drinking water, while 2.6 billion (40
percent of the world's population hasn't improved much since.
• According to a WASA report, it is estimated that farm waste has
been estimated to produce over (55%) of the total waste load.
Trinidad and Tobago was also estimated as 10.4 million
kilograms/year with 45% being contributed from domestic
sources & 55% from live stock. Mean while, Tobago accounts
for 4% of both the domestic waste and live stock waste.
• Water pollution arising from accidental or deliberate
disposal of harmful substances on land, dumping of petrochemicals at sea, over-use of pesticides and fertilizers and
poor sewage systems, all of which results in contamination
of both surface and ground water. Water Pollution is a
serious issue and preventive measures are essential
• “ Are You Water Wise?”