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Bilingual & International ChemistryUNIVERSITAS NEGERI MEDAN

2012

Lecture Note 5

WATER POLLUTIONProf. Drs. Manihar Situmorang, M.Sc., PhD

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The quality of drinking water is used to measure the welfare of the nation

Disease: In developing nations, 80% of diseases are water-related. Synthetic Organic CompoundsInorganic Compounds & Mineral

Substances such as Acids, etc.Radioactive substancesOxygen-demanding wastesPlant NutrientsSedimentsThermal Discharges

Introduction

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Indicators for Water Pollution

Defined as the change of natural water from normal condition becomes potentially to harm organism (unhealthy water) Could be seen from the change in

physics appearance, chemicals contents, thermal change, biological, and radioactive

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Water Pollution

Indicators for Water pollution1) Change in temperature2) Change in pH, basic or salt3) Change in color (visualized),

odor, taste4) Formation of coagulant, colloids5) The presence of microorganism

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1. Change in Temperature The change in the temperature of water Could be caused by the human activities

(machine, industries, etc) Influencing the solubility of O2 in water Influencing the physiological of aquatic

organism such as fish, etc

Increasing the temperature of water will results to increasing the toxicity of chemicalsMultiplication on the toxic ability of the

chemicals in water

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2. Change in pH, Basic and Salt

pH of normal water is in the range of pH 6.0 – 7.5

To be survive, an organism has to adapt with the salinity, basic condition and the pH of the water through osmotic process

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2. Change in pH, Basic and Salt

The change in the pH, basic and salt of water occurred from nature and the activity of organism Microorganism degraded organic and

inorganic minerals to become acid, basic or salt

Sulfuric acid could decreases the pH of water very low (pH 3.0) because the minerals contains sulfur decay

The presence of basic in ore will increase the pH of water up to pH 9.0

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2. Change in pH, Basic and Salt

The change in the pH, basic and salt of water could be caused by the human activities (fertilizer, waste of industries, etc) Influencing the pH of water will force the

aquatic organism to be adapted survive• Fish and plants survive in fresh water• Fish and plants survive in sea water

Influencing the physiological of aquatic organism such as fish, etc

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2. Change in pH, Basic and Salt

Increasing the pH, basic or salt mainly coming from Human activity Natural (Degradation of minerals,

organic materials, etc)

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3. Change in Color, Odor, Taste

Normal water is invisible, odorless, tasteless The change in color, odor and taste of water Could be caused by the human activities

such as home waste or industrial waste, etc in the form of various waste

• Dye• Organic and inorganic chemicals• Degradation of minerals, organic materials, etc

Change in the color, odor and taste of water will Influence the chemical properties of fresh water

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4. Formation of coagulant, colloids Formation of coagulant, colloids could be

coming from insoluble industrial waste Formation of coagulant or colloids is also

coming from ions (anion-cation) The presence of coagulant and colloids in

water will result in:Reduce the intensity of light Effect in photosynthesis process Reduce in O2

Influence the aquatic life

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Microorganism in Water The presence of pathogenic microorganism

in water potentially as the source of various diseases

Waste from food and home industries in water will multiply the number of pathogenic microorganism in water Bacteria Fungus Algae as producer since it will converted light

becomes energy

As reducer since they convert complex chemicals become simple elements

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Waste Water Component

Waste water components consisted of: Solid waste Inorganic waste Organic waste Food waste Oil and oily waste Chemical waste

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Waste Water Component

1) Solid waste solid waste enter the water in the form of : Colloid will influence the visibility

of water aquatic life Slump will influence the condition

of river

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Single large sourceCan localize it to one spotIndustrial PlantsSewage pipes

Source of Solid Waste Water

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Waste Water Component

2) Inorganic waste waste from industry (metals, electroplating, electronics, chemicals) enter the water Will influence the conductivity of water

and the hardness of water Toxic to organism Difficult be removed (degrade by

organism) Difficult to identify (only by using modern

analytical tools) Last longer in water

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Source of Industrial Waste

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Waste Water Component

3) Organic waste waste from industry (Food, drink, pharmaceuticals, rubber, etc) enter the water Will influence the population of

microorganism in the water Toxic to organism Changing the ecosystem

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Water Polutant

Forms of Pollution Organic: sewage, pesticides,

plastics, etc. One drop of oil can render up to 25

liters of water unfit for drinking One gram of 2,4-D can contaminate

10 million liters of drinking water! One gram of PCBs can make 1 billion

liters of water unsuitable for freshwater aquatic life!

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Waste Water Component4) Food waste waste from industry (Food,

drink, etc) enter the water Will influence the population of

microorganism in the water Toxic to organism Bad odour (bad smell due to N, S)

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Waste Water Component5) Oil and oily waste waste from industry (oil, Food

waste, etc) and oil from machinery enter the water Will influence the visibility of water (reduce the

light, exhibit the photosynthesis) Toxic to organism do to limited dissolve oxygen

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Waste Water Component

6) Chemical waste waste from chemical industry (detergent, pesticide, etc) enter the water Will influence the population of

aquatic organism in the water Toxic to aquatic organism

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Waste Water Component

Forms of Pollution as Chemical waste :Inorganic – acids, salts, toxic metalsOne gram of lead in 20,000 liters of

water makes it unfit for drinking. Lead is often found in the pipes of older homesWhat is the safe drinking water limit for

arsenic? For lead? How much does UA water supply have?

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Waste Water Component

Chemical waste (heavy metal, organics chemicals, pesticide, etc (see examples in the text book)

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Chemical Waste

Chemical waste (heavy metal, organics chemicals, pesticide, etc (see examples in the text book)

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Trace Metal

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Heavy Metal in Water Heavy metal that are commonly found as chemical

waste in water:1) Arsenic from fossil, pesticide (Pb3(AsO4)2;

Na3AsO3; paris green Cu3(AsO4)2) very toxic and carcinogenic

2) Cadmium very toxic, the same properties with Zink (enzymatic reaction)

3) Lead from fossil (oil) toxic and harmful to human

4) Mercury from minerals, organometallic (fungicide) very toxic, mutagenic

Hg S CS

N(CH3)2

(Fenil merkuri dimetilditiokarbamat)

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Pesticide in Water Pesticide that are commonly found in water Insecticide for insect Rodentiside for Rhodesia Aviside for bird Ficiside for fish Herbicide for plant

Name of pesticide and their structure are presented in page 96-98

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Detergent in Water Detergent is a salt and easily dissolve in water,

containing of surfactant as an active material to lower the hardness of water Alkyl benzene sulphonate (ABS) difficult

degrade by microorganism potentially as pollutant

SO

OONa+ + CH

CH3

CH2 CHCH3

CH2CH3

CH2CHCH3

CH2HC CH

CH3

CH3

ABS (alkil benzen sulfonat)

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Detergent in Water

α–dodekana benzensulfonat or linear alkyl benzene sulfonat (LAS) easily degrade by microorganism save for environment

SO OO

LAS (α-dodecanebenzen sulfonat)

CHH3C CH2 CH2 CH2 CH2 CH2 CH2 CH CHH2C CH3

Na+

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Cyanide in Water Cyanide as NaCN and KCN are used to extract gold

and silver in mining

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Assignment 4 Write a short assay (2-4 pages) on the issue of

water pollution It is good if you could present with photos

or other sources You could also write its relation to the

health, diseases or disaster The topic could also taken from the news or

related articles Never copy paste, plagiat, and double

submission Due date submission on week 10