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Causes and Impact of Water Pollution and its Adverse Effects on Health
33
CHAPTER-2
CAUSES AND IMPACT OF WATER POLLUTION AND ITS
ADVERSE EFFECTS ON HEALTH
Environment is a precious gift of God to all creatures whether living or non-living. The
natural resources of the earth including air, water, land, flora and fauna and especially
representative samples of ecosystems must be safeguarded for the benefit of the present
and future generations through careful planning and management.1 Water is a liquid of
life, as there can be no life without water. Pure water is an animating fluid while polluted
water is a real curse for living beings. Accordingly, causes and impact of water pollution
and its adverse effects on health of human beings will be looked into.
Man during course of his civilization has settled in places where plenty of water was
available. But with the increase of population and in exploitation of natural resources for
his own benefit, he has behaved in a wild manner by creating problems of pollution
hazardous not only to aquatic life but also to his own life. While western countries have
become quite sensitive to this problem, India is still continuing, because of irresponsible
behaviour of its citizens, in rendering water more polluted day by day and the situation is
deteriorating progressively.2
The water resources on the earth are depleting fast. Out of several components of
environment, water, being traditionally the most convenient receptacle for the society in
India, has been polluted to the threshold. The water resources are limited but the assault
in the form of pollutants is an ongoing process. About 70 percent of all available water in
India is feared polluted. This state of affairs is really alarming.3 Without pollution
1 S.Shanthakumar, Introduction to Environmental Law,Wadhwa and company, Nagpur, 2
nd
edition,2005, p.394. 2 A.K.Tripathi and S.N.Pandey, Water Pollution, APH Publishing Corporation, New Delhi, 2009, p.3.
3 Ali Mehdi, ― Water Pollution Laws and Their Enforcement In India‖, First Edition, R. Cambray
And Co. Private Ltd.,Kolkata,2007,p.1.
Causes and Impact of Water Pollution and its Adverse Effects on Health
34
controls, water would become grossly polluted and unusable for a wide range of human
and non human needs.4 The problem of water resources is not less urgent than that of
other types of pollution.5 ―It is not a problem of an individual or a nation but is a problem
which ‗no nation, no continent, no hemisphere, no race, no system can handle alone‘. It is
a problem of entire human race which requires joint action‖.6 An adequate supply of safe
drinking water is one of the major pre-requisites for a healthy life. The importance of
clean water and link between contaminated or putrid water and illness was recognised in
the distant past, even though the actual case of disease was not properly understood until
the latter half of the 19th
century.7 During recent years there has been increasing
awareness of, and concern about, water pollution all over the world, and new approaches
towards achieving sustainable exploitation of water resources have been developed
internationally.8
2.1 MEANING OF PURE WATER
It can be said that no water is pure or clean owing to the presence of some
quantities of gases, minerals and life. However, for all practical purposes, pure water is
considered to be that which has low dissolved and suspended solids and obnoxious gases
as well as low in biological life. Such a high quality of water may be required only for
drinking purposes while for other uses like agriculture and industry, the quality of water
can be quite flexible and water polluted up to certain extent, in general sense, can be
regarded as pure.9
4 Susan Wolf, Anna White And Neil Stanley, Principles Of Environmental Law, Cavendish
Publishing Limited, London, Third Edition ,2002,p.59. 5 M.V.Zaytseva, ―Ecological Problems”, Conference Paper of Fifth International Conference on
International Environmental Law Organised by The Indian Society of International Law, New
Delhi, 8-9 December, 2007, p.199. 6 Chetan Singh Mehta, Environmental Protection and the Law, Aashish Publishing House, New
Delhi, 1991, p.9. 7 Ray M. Harrison, Pollution : Causes, Effects and Control, Royal Society of Chemistry,
Cambridge,Fourth Edition, 2001, p.59. 8 Richard Helmer and Ivanildo Hespanhol, Water Pollution Control, E and FN Spon, London, First
Edition, 1997, p.1. 9 P.K.Goel, Water Pollution: Causes, Effects and Control, New Age International, 2006, p.1.
Causes and Impact of Water Pollution and its Adverse Effects on Health
35
2.2 WATER POLLUTION
The term water pollution has been used differently in various Indian Acts. Some
described it as ‗nuisance‘, while others as negligence. ‗Fouling‘ of water was also the
way of describing as ‗poisoning‘ of water. Some acts described as rendering water ‗less
fit‘ or ‗not fit‘ for consumption by human beings and animals. Interference with or
alteration in flow of water to carry away rubbish or causing water to be corrupted in any
waterway so as to endanger, damage or render it less useful, was another mode of
explaining the term water pollution. Before the enactment of the Water (Prevention and
Control of Pollution) Act, 1974, almost all the statutes, stressed upon the mode of causing
pollution rather than explaining ‗pollution‘ itself. In a simple sense, water pollution is
―adding of any substance to water or the changing of water‘s physical and chemical
characteristics in any way which interferes with its use for legitimate purposes‖.10
Water is colourless and transparent substance. The polluted water means such water
which contains foreign substances in it, which alters physical, chemical or biological
properties of water rendering it unfit for use.11
According to the Water (Prevention and Control of Pollution) Act, 1974, ―water pollution
means such contamination of water or such alteration of the physical, chemical or
biological properties of water or such discharge of any sewage or trade effluent or of any
other liquid, gaseous or solid substance into water (whether directly or indirectly) as may
or is likely to, create a nuisance or render such water harmful or injurious to public health
or safety or to domestic, commercial, industrial, agricultural or other legitimate uses, or
the life and health of animals or plants or of aquatic organisms.‖12
10
Jaspal Singh, Water pollution: Sources, Health Problems and Its Control with Special Reference to
Punjab, Law Journal, Guru Nanak Dev University, Vol. 11, 2002, p.73. 11
Javaid Talib, Water Pollution : Legal Regime And Its Effectiveness, Religion And Law Review,
Vol.14, 2005, p.120. 12
Section 2(e), The Water (Prevention and Control of Pollution) Act, 1974.
Causes and Impact of Water Pollution and its Adverse Effects on Health
36
The total amount of water on the earth is about 1.35 billion cubic kilometres (3.5x1020
gallons). Over 97 percent of this quantity is in the oceans as salt water. The earth‘s fresh
water amounts to only 37 million cubic kilometres of which 80 percent occurs in polar
ice caps and glaciers. The water we use comes from 50 cubic kilometres per day run off
in the rivers, streams and lakes and 70 cubic kilometres per day flow through
underground reservoirs. This supply has been constant over tens of thousands of years.
Only the demand has shown a steep increase over the last century. Due to this increase, in
India the average annual availability of water per capita has declined from 5236 cubic
meters in 1951 to only 2227 cubic meters in 1991. As per estimates, this will further
decline to only 1555 cubic meters by the year 2013. The population of India, which is
now more than one billion, is expected to reach a figure between 1.5 billion and 1.8
billion in the year 2050. There shall then be a requirement of 2788 billion cubic metres of
water annually in India to be above water stress zone and 1650 billion cubic metres to
avoid being water scarce country.13
2.3 WATER POLLUTANT
There are hundreds, perhaps thousands of pollutants whose effects are of actual and
potential concern. Their numbers increase annually as new compounds and formulations
are synthesised.14
Several attempts have been made to group water pollutants into classes
or categories. Pollutants have been classified according to their mode of occurrence into
physical, chemical and biological pollutants.15
13
Javaid Talib, Water Pollution : Legal Regime And Its Effectiveness, Religion And Law Review,
Vol.14, 2005, p.120. 14
P.D.Abel, Water Pollution Biology, Taylor And Francis, London, Second Edition, 1996, p.29. 15
S. K. Agarwal, Water Pollution, APH Publishing Corporation, New Delhi, 2009, p.54.
Causes and Impact of Water Pollution and its Adverse Effects on Health
37
TABLE 2.1
CLASSIFICATION OF WATER POLLUTANTS16
Occurrence Nature Examples
Physical
Temperature
Turbidity
Colour
Suspended and
floating matter
Waste neat from industry.
Dyes and pigments
Silt, sand, metal pieces, rubber, wood chpis, paper,
foam, scum, carcasses, sewage.
Chemical
Inorganic
Organic
Nitrites, phosphates, chlorides, fluorides, salts etc.
Detergents, tar, plastic, pesticides.
Biological
Pathogenic
Nuisance
organisms
Bacteria, virus, nematodes, worms, protozoans.
Slime, mollusc, algae, Ascellus, nematodes.
16
S.K.Agarwal, Water Pollution, APH Publishing Corporation, New Delhi, 2009, p.55.
Causes and Impact of Water Pollution and its Adverse Effects on Health
38
2.4 CAUSES OF WATER POLLUTION
Some of the major factors which are responsible for causing water pollution or
degradation can be enumerated as growing population, rapid industrialization,
urbanisation, use of science and technology and modern agriculture practices.
2.4.1 Growing Population
Every year we add millions of people to the world population and our country is no
exception. Now it is the second largest country of the world after China and the rate of
growth still continuous alarmingly. The earth is now overcrowded and consumption habit
of the people is on the rise.17
The growth of population gave rise to increase in wants and
demands of mankind and has succeeded in creating acute problem of water pollution.18
2.4.2 Industrialization
Rapid industrialization is another cause of worry as far as water pollution is concerned.
Immediately after the independence, major steps were taken in our country in its stride
for development in order to give its economy a big push. Industrialization was then
considered the most important factor that can put the country in the path of progress. But
to our utter surprise industrialization along with development brought with it a danger to
the human civilization- the problem of environmental pollution.19
2.4.3 Urbanization
Urbanization is also another major factor which contributes significantly towards
environmental pollution. From the earlier base we noticed that generally the civilization
17
Sukanta K.Nanda, Environmental Law, Central Law Publishers, Allahabad, Third Edition, 2013,
p.10. 18
T.H.Khan, ―Legal Control of Water Pollution‖, Central India Law Quarterly, Vol. IV., July-Sep.
1991, p.352. 19
Supra 17, p.11.
Causes and Impact of Water Pollution and its Adverse Effects on Health
39
started near the water courses. Subsequently big cities also developed just near the water
courses particularly besides the big rivers. Water is considered as life and we owe a great
deal to water for the sustenance of our lives. Thus with the development of the big cities
all other forms essentials for making the life comfortable also developed. Of these,
developments in the field of communication and transportation are noteworthy which
subsequently attracted the establishment of industrial and commercial basis in and around
the cities. As these sectors heavily depend on water and all advance system, it is natural
that the cities were their first choice. Since many towns and cities lack a proper sewerage
system, the condition worsened further adding to the misery of the people20
.
2.4.4 Nature of Modern Technology
The nature of productive technology in recent years is closely related to the
environmental crises. This factor has been largely responsible for the generation of
synthetic and non biodegradable substances such as plastics, chemical nitrogen fertilizers,
synthetic detergents, synthetic fibres, big cares petrochemical and other environmentally
injurious industries and ―disposable culture‖. Thus, an environmental crisis is the
inevitable result of a counter ecological pattern of productive growth21
.
2.4.5 Modern Agricultural Practices
Modern agricultural practices and application of new technological processes in the field
of agriculture severely affect the environment. Inorganic fertilizers are being widely used
now-a-days. Fertilizers like phosphates and nitrates cause wide spread damage when
applied carelessly to crops. The fertilizers can be transmitted to ground water by leaching
and to surface waters by natural drainage and storm run-off. In addition to fertilizers
20
Ibid., 12. 21
Kailash Thakur, Environmental Protection Law and Policy in India, Deep And Deep Publishers,
New Delhi,1997, p.22.
Causes and Impact of Water Pollution and its Adverse Effects on Health
40
various kinds of pesticides and insecticide also applied. Almost all the pesticides those
are used are toxic to human and animals22
2.5 TYPES OF WATER POLLUTION
Pollution of water can take any one or more of physical, chemical, physiological and
biological forms.
2.5.1 Physical Pollution
2.5.1.1 Temperature
The increase in temperature of water bodies due to the heated discharges like the one
from power stations can lead to thermal pollution. As the solubility of oxygen in water is
inversely proportional to the temperature, dissolved oxygen (DO) in the water at a higher
temperature would be reduced. Higher temperature may also increase the biological
activities requiring greater quantities of DO for respirational purposes and affect
adversely the growth and survival of aquatic life especially the delicate fishes and
bacterial population due to inadequate DO. 23
2.5.1.2 Turbidity
It is mainly due to the presence of colloidal or finely divided suspended matter which
does not readily settle e.g. river water in monsoon, water polluted with sewage and
wastes from ceramic and paper industries. It can also be caused by iron and manganese
salts due to their conversion into insoluble hydroxides. Turbidity reduces the penetration
of sunlight into the water for green aquatic plants (which give oxygen to water),
22
Supra 17, p.13. 23
Jivendra, Water Pollution Management, APH Publishing Corporation, New Delhi, 1995, p.82.
Causes and Impact of Water Pollution and its Adverse Effects on Health
41
adversely effecting the photosynthesis resulting in the death of the plants and thus
reducing the oxygenation in the stream.24
2.5.1.3 Suspended matter
Suspended matter can be inorganic or organic and includes soil and mineral particles
from the land by storm and flood water from cropland unprotected forest soil, overgrazed
pasture, strip mines, road and bulldozed urban area. Suspended solids deposit on the bed
of the water body receiving them, if the quantity is high or flow of water low, causing
sediments which will change the nature of the bed and affect fauna and flora, certain
aquatic organisms and reproduction of animal life at the bed. It will also reduce the
sunlight affecting the photosynthetic activity essential to maintain healthy conditions in a
stream. 25
2.5.1.4 Colour
The colour of water can vary due to natural or artificial sources. Running through peaty
soils, water obtains a brownish tint primarily due to lignin and other related bodies which
are also obtained due to rotting of plant materials. Such a colour forms an aesthetic
pollution. Artificial colours are discharged from textile industries due to dyestuffs, from
tanning industries due to tannins and use of dyes, from pulp industries due to lignin and
dyes and from steel picking industries due to ferrous sulphate or ferric chloride after
conversion into red brown ferric hydroxide. Dyestuffs, even in small quantities, may give
rise to visible colour.26
2.5.1.5 Foam
Synthetic detergents and certain natural compounds are known to cause foam by lowering
down the surface tension of water. Several of the advanced countries had faced problems
of foam in their sewage waste water and rivers due to increased use of synthetic
24
Jivendra, Water Pollution Management, APH Publishing Corporation, New Delhi, 1995, p.82. 25
Id. 26
Ibid., p. 83.
Causes and Impact of Water Pollution and its Adverse Effects on Health
42
detergents in the recent decades. Foam can be hazardous as it can carry suspended solids
including pathogenic bacteria if present in water.27
2.5.1.6 Radioactivity
Radioactive substances, detected only buy specific instruments, present in waste
from uranium and thorium mining and refining industries, nuclear power plants and
industries, medical and scientific institutions utilizing radioactive substances, can pose
dangerous situations. 28
2.5.2 Chemical Pollution
2.5.2.1 Inorganic Pollution
Corrosive acids in water give rise to corrosion of metals, concrete structures and pumps
etc. coming in its contact. Many industries discharge acids in their wastewater, common
one being sulphuric and hydrochloric acids. Certain wastes may contain toxic inorganic
substances such as free chlorine, ammonia, hydrogen sulphide, soluble sulphides and
salts of many metals like copper, zinc, lead, nickel, chromium, cadmium, silver, mercury,
iron, uranium, vanadium and thorium etc.29
2.5.2.2 Organic pollution
The most common form of organic pollution is due to the presence of carbohydrates, fats,
proteins and similar other organic substances found in sewage and other industrial
wastes. Untreated sewage and domestic wastes including wastes from sanatoriums,
hospitals and slaughter houses contains complex organic substances in the form of urine,
faeces, paper, soap, detergent, scrap of food and grease etc.30
27
Id. 28
Id. 29
Ibid., p.84. 30
Ibid., p.86.
Causes and Impact of Water Pollution and its Adverse Effects on Health
43
2.5.3 Physiological Pollution
Taste and odour, although may not pose public health problems, are considered aesthetic
pollutants. Several industrial wastes impart odour and unpleasant taste. Salts of iron,
manganese and chlorine, H2S, phenols and unsaturated hydrocarbons are some of the
examples.31
2.5.4 Biological Pollution
It is the result of wastes containing pathogenic forms of bacteria, certain fungi, algae,
viruses, pathogenic protozoa, parasite worms, helminthic parasites and indeed any plant
or animal which multiplies excessively in the water bodies for one reason or the other.
This pollution is often a result mainly of the domestic sewage and human excreta and at
times certain industrial wastes.32
2.6 SOURCES OF WATER POLLUTION
The sources of water pollution are innumerable. Major sources can be found in
practically every variety of industrial, municipal and agricultural operations.33
The main
sources of water pollution are as under:
1. Domestic wastes ;
2. Industrial wastes ;
3. Agricultural wastes, insecticides and pesticides ;
4. Thermal pollution ;
5. Marine pollution ; and
6. Radioactive wastes.
31
Ibid., p.89. 32
Id. 33
Rene Dubos, Health Effects Of Environmental Pollution, United States Environmental Protection
Agency, Washington D.C., 1973, p.8.
Causes and Impact of Water Pollution and its Adverse Effects on Health
44
2.6.1 Domestic Wastes
Wastes from residential homes, sewage etc. constitutes nearly 70 percent of the water
pollution. The residential buildings do have connected sewage treatment system but it is
either inadequate or misused. The garbage and sewage discharged from it is flown in
drains or sewage lines thereby blocking the free flow of water.
Sewage generally includes bio-degraded pollutants such as human excretion, animal
waste and many compounds like carbohydrates, proteins, urea, fats etc. as also inorganic
nitrates and phosphates of detergents which cause water pollution. The detergent
accumulated in water render it unfit for drinking purposes.
According to a recent survey, an average Indian family throws away wastes of about 60
kg per week. About 60 percent of the wastes processed by municipal treatment plants
come from domestic sources and around 40 percent from industrial units. The thickly
populated areas are more prone to the ill-effects of contaminated water.
The water discharged from untreated or inadequately treated sewage which goes into
rivers, lakes, wells etc. causes serious infectious diseases like typhoid, cholera, dysentery
and other skin diseases.34
2.6.2 Industrial Wastes
Industrial waste or trade effluent includes any liquid or solid substance, which is
discharged from any premises used for carrying on any industry, operation or process or
treatment and disposal system other than the domestic sewage. It is a common practice
that a large number of industries, which are located on the banks of rivers, discharge their
34
Vinay N. Paranjape, Environmental Law, Central Law Agency, Allahabad, First Edition, 2013,
p.117.
Causes and Impact of Water Pollution and its Adverse Effects on Health
45
effluent into the river and thus pollute the river water. Industrial effluents contain, inter
alia, mercury, lead, cadmium and copper etc., which are harmful to the aquatic animals.35
2.6.3 Agricultural Wastes, Insecticides and Pesticides
The main pollutants of agricultural wastes that cause water pollution are pesticides and
fertilizers which reach water through run off and leaching. Sediments and farm-animals
wastes also cause water pollution. The pesticides and insecticides which are sprinkled in
agricultural farms when washed off the lands through irrigation, drainage or rainfall,
enter into rivers, streams and even soaked underground and the water gets contaminated.
The excessive use of inorganic fertilizers accelerates nitrite contents in water and it gets
polluted.36
2.6.3.1 Pesticides
Pesticides are substances or mixture of substances intended for preventing, destroying,
repelling or mitigating any pest. A pesticide is generally a chemical or biological agent
(such as a virus, bacterium, antimicrobial or disinfectant) that through its effect deters,
incapacitates, kills or otherwise discourages pests. Target pests can include insects, plant
pathogens, weeds, birds, mammals, fish, nematodes (roundworms), and microbes that
destroy property, cause nuisance, spread disease or are vectors for disease. Although
there are human benefits to the use of pesticides, some also have drawbacks, such as
potential toxicity to humans and other animals. According to the Stockholm Convention
on Persistent Organic Pollutants, 9 of the 12 most dangerous and persistent organic
chemicals are pesticides.37
Pesticides cause widespread pollution of various fresh water
bodies like rivers, lakes and estuaries.38
35
P.S.Jaswal and Nishtha Jaswal, Environmental Law, Allahabad Law Agency, Faridabad, Third
Edition,2009, p.198. 36
Supra 34, p. 118. 37
Retrieved from <http://en.wikipedia.org/wiki/Pesticide visited on 5 June, 2012. 38
S.K.Agarwal, ―Water Pollution”, APH Publishing Corporation, New Delhi, 2009, p. 33.
Causes and Impact of Water Pollution and its Adverse Effects on Health
46
2.6.3.2 History of Pesticides Usage
Since before 2000 BC, humans have utilized pesticides to protect their crops. The first
known pesticide was elemental sulfur dusting used in ancient Sumer about 4,500 years
ago in ancient Mesopotamia. The Rig Veda, which is about 4,000 years old, mentions the
use of poisonous plants for pest control. By the 15th century, toxic chemicals such as
arsenic, mercury and lead were being applied to crops to kill pests. In the 17th century,
nicotine sulfate was extracted from tobacco leaves for use as an insecticide. The 19th
century saw the introduction of two more natural pesticides, pyrethrum, which is derived
from chrysanthemums, and rotenone, which is derived from the roots of tropical
vegetables. Until the 1950s, arsenic-based pesticides were dominant.
39
2.6.3.3 Effect of Pesticides Usage
Pesticide exposure can cause a variety of human health problems, both chronic and acute.
Chronic effects are typically the result of low levels of exposure over a long period of
time. These can occur even if there are no acute or immediate effects. Major health
impacts from chronic exposure include cancers, reproductive and endocrine disruption,
neurological damage, and immune system dysfunction. According to the World Health
Organization (WHO), long-term regular exposure to pesticides causes approximately
772,000 new cases of diseases every year.40
If we take into account the current regulatory
systems related to pesticides in India, we find that while the Insecticides Act of 1968
under the Ministry of Agriculture governs the registration, production, sale, export and
import of pesticides (referred to as Insecticides in the legislation), it is the Prevention of
Food Adulteration (PFA) Act 1954 under the Ministry of Health and Family Welfare and
Bureau of Indian Standards which regulate food and water quality. Tolerance limits either
in the form of Acceptable Daily Intake (ADI) of a pesticide or a Maximum Residue Limit
(MRL) on food commodities are not legally fixed at the time of a pesticide‘s registration
39
Retrieved from <http://en.wikipedia.org/wiki/Pesticide visited on 5th June, 2012. 40
Kavitha Kuruganti, ―Effects of Pesticide Exposure on Developmental Task Performance in Indian
Children‖, Children, Youth and Environments, Vol. 15, No. 1, 2005, p. 84.
Causes and Impact of Water Pollution and its Adverse Effects on Health
47
and, therefore, not all registered pesticides have a tolerance limit set. While the
Insecticides Act mandates registration of pesticides, the PFA Act sets MRLs. On analysis
of the pesticides registered, we find that out of 180 pesticides registered in India as of
2003, MRLs had been set for only 71. Also, the PFA Act does not set ADIs which are
more directly connected with safety levels, but only concerns itself with MRLs—another
illustration of the lax standards with regard to pesticides in India. MRLs do not
specifically address children‘s unique vulnerability or the situation of complex cocktail
exposure on the ground. There is no enforcement mechanism for ensuring recommended
agricultural pesticide practices.41
The nature of the health effects from pesticides depends on the type of pesticide, dose,
timing and duration of exposure, as well as the particular susceptibility of the exposed
individual. Farming community members have little or no control over several or all of
these factors.42
2.6.3.4 First Voice Raised Against the Use of Pesticides
First voice raised against the use of pesticides and insecticides was of Rachel Carson in
her book ‗silent spring‘ which was published in 1962.in this book Rachel Carson
described numerous case studies where use of hazardous pesticides and insecticides led to
environmental problems all over the world. Her book described, in depth the harmful
effects of insecticide and pesticides on all components of the environment.
2.6.3.5 DDT-Noble Prize Winner (1948)
It is interesting in this context that the discovery of the insecticidal properties of DDT
occasioned a Nobel Prize in 1948. For the next decade, the culture continued to bask in
the triumph of DDT and the promise of "better living through chemistry"43
41
Ibid., at p. 85. 42
Ibid., at p. 110. 43
Retrieved from<http://www1.umn.edu/ships/pesticides/intro.htm visited on 25th May, 2012.
Causes and Impact of Water Pollution and its Adverse Effects on Health
48
2.6.3.6 Effect of Silent Spring
As a result of Rachel Carson‘s Silent Spring, the Environmental Protection Agency
(EPA) banned the use of DDT in United States in 1972.
In the 1970s and 1980s, agricultural use was banned in most developed countries,
beginning with Hungary in 1968, then in Norway and Sweden in 1970, Germany in 1972,
United Kingdom in 1984. The Convention has been ratified by more than 170 countries
and is endorsed by most environmental groups.44
Unfortunately India refuses to ban this
pesticide and continues to say that it is safe. India the largest producer of this chemical
does not want to disturb the profit it earns by producing and exporting this deadly poison
to 70 countries.45
2.6.3.7 W.H.O Classification of Pesticide
Pesticide belonging to W.H.O. class I a is extremely hazardous, class I b is highly
Hazardous, class II is moderately hazardous, class III is slightly hazardous and class IV is
unlikely to present acute serious hazards in normal use. Nearly 90 percent of the banned
pesticides fall into category Ia/ Ib/ II of the W.H.O. hazard grades. Applications of
monocrotophos, cypermethrin, methamidophos and dimethoate have been increased
many folds in developing countries46
44
Retrieved from<http://en.wikipedia.org/wiki/DDT#Silent_Spring_and_the_U.S._ban visited on
28th May, 2012. 45
Retrieved from<http://www.living-farms.org/site/media-/press-releases/226-pesticide-banned-in-
62-countries-still-used-in-india visited on 8th June, 2012. 46
Retrieved from http://www.intechopen.com/download/get/type/pdfs/id/13227 visited on 22
December, 2013.
Causes and Impact of Water Pollution and its Adverse Effects on Health
49
TABLE NO. 2.2
CLASSIFICATION OF PESTICIDES USED BY THE FARMERS SURVEYED47
PESTICIDE
PRODUCT
ACTIVE
INGREDIENT
CHEMICAL
CLASS
TOXICO-
LOGICAL
CLASS*
MAIN USE
BASUDIN Diazinon Organophosphates II Insecticide
HERBOXONE 2,4-D Chlorophenoxy
acids II Herbicide
TOPIK Clodinafop-
propargyl
Aryloxyphenoxy
Propionics
III Herbicide
AATREX Atrazine q Triazines U Herbicide
MACHETE Butachlor Chloroacetanilides U Herbicide
CERTAINTY Sulfosulfuron Sulfonylureas U Herbicide
ERADICANE EPTC Carbamides II Herbicide
47
Retrieved from http://www.intechopen.com/download/get/type/pdfs/id/13227 visited on 22
December, 2013.
Causes and Impact of Water Pollution and its Adverse Effects on Health
50
LASSO Alachlor Chloroacetanilides III Herbicide
DECIS Deltamethrin Pyrethroids II Insecticide
ALTO Cyproconazole Triazoles III Fungicide
SENCOR Metribuzin Triazines II Herbicide
CONFIDOR Imidacloprid Neonicotinoids II Insecticide
GRANSTAR Tribenuron-
methyl Sulfonylureas U Herbicide
* Ia = Extremely hazardous; Ib = Highly hazardous; II = Moderately hazardous; III =
Slightly hazardous;
U = Unlikely to present acute hazard in normal use
Causes and Impact of Water Pollution and its Adverse Effects on Health
51
(a) Organophosphates
They were developed during the early 19th century, but their effects on insects, which are
similar to their effects on humans, were discovered in 1932. Some are very poisonous
(they were used in World War II as nerve agents). They are generally highly lipid soluble
and may be classified as direct or indirect acetylcholinesterase (AchE) inhibitors.
However; they usually do not persist in the environment. The organophosphates (OPs),
because of their widespread use and frequently high acute toxicity, are involved in more
pesticide poisonings than any other class of pesticides. The organophosphates interfere
with the activity of cholinesterase. When the cholinesterase enzyme cannot perform its
normal function, the nerves in the body send ―messages‖ to the muscles continuously
leading to muscle twitching and weakness. If the poisoning is severe, the victim may
have ―fits‖ or convulsions and may even die. Organophosphates are irreversible
cholinesterase inhibitors, without medical treatment the level of enzyme activity will
return to normal only after several days, weeks or even months. Additive effects of small
repeated doses over time, such as in a spraying season, may finally cause poisoning. The
effects of mild poisoning include fatigue, headache, and dizziness. Moderate poisoning
leads to inability to walk, weakness and chest discomfort. In severe cases there will be
unconsciousness, severe constriction of pupils and muscle twitching ultimately resulting
in death.48
(b) Methamidophos
It is classified by Environmental Protection Agency (EPA) as a class I compound.
Methamidophos is a highly active, systemic, residual organophosphate insecticide/
acaricide/avicide with contact and stomach action. Methamidophos, a potent
acetylcholinesterase inhibitor, is highly toxic via oral, dermal and inhalation routes. Early
48
Retrieved from http://www.intechopen.com/download/get/type/pdfs/id/13227 visited on 22
December, 2013.
Causes and Impact of Water Pollution and its Adverse Effects on Health
52
symptoms of acute organophosphate poisoning are dependent on route of exposure, and
usually develop during or shortly after exposure (within 12 hours). Weakness, shakiness,
blurred vision, tightness in the chest, sweating, confusion, changes in heart rate,
convulsions, coma, and cessation of breathing may occur with significant inhalation,
ingestion or dermal exposure. The Allowable Daily Intake (ADI) level of methamidophos
is 0.0003 mg/kg.49
(c) Carbamates
The effects of carbamates and organophosphates are similar because they both
inhibitcholinesterase. Action of carbamates is naturally reversible as compared to
methamidophos action of carbamates is naturally reversible (they will be degraded in
and/or expelled from the body). Thus, carbamates can cause severe severe poisoning, but
they do not normally produce long-term, cumulative poisoning. The symptoms of acute
carbamate and organophosphate poisoning are essentially the same.50
(d) Methomyl
Methomyl is a carbamate insecticide. It is broad spectrum fast acting anti-cholinesterase
agent. It is a direct contact and stomach poison. It is a plant systemic of high acute
toxicity to mammals. It is non-cumulative and rapidly metabolized in both plants and
animals to substances of lower toxicity. Methomyl is particularly effective against
organophosphorus resistant pests. Methomyl may be absorbed from the gastrointestinal
tract, through the intact skin, and, by inhalation of spray mist and dust. The ADI levels of
methomyl are 0.01mg/kg.51
49
Id. 50
Id. 51
Id.
Causes and Impact of Water Pollution and its Adverse Effects on Health
53
(e) Thiodicarb
It is a carbamate pesticide and belongs to class II, moderately hazardous pesticide.
Symptoms ymptoms include malaise, muscle weakness, dizziness, sweating headache,
salivation, nausea, vomiting, abdominal pain, diarrhea, central nervous system depression
and pulmonary edema. The ADI levels of thiodicarb is 0.03 mg/kg.52
(f) Organochlorines
They were commonly used in the past, but many have been removed from the market due
to their health and environmental effects and their persistence (e.g. DDT and
chlordane).53
(g) Endosulfan
It is an organochlorine pesticide of moderate mammalian toxicity which does not
accumulate in the tissues of man or animals to any significant extent. Undiluted
endosulfan is slowly and incompletely absorbed in the gastrointestinal tract of warm-
blooded animals. Absorption is more rapid in the presence of alcohols, oils and
emulsifiers. These substances also accelerate the absorption of endosulfan through skin.
It is a central nervous system stimulant, producing convulsions. The ADI level of
endosulfan is 0.006 mg/kg.54
52
Id. 53
Id. 54
Id.
Causes and Impact of Water Pollution and its Adverse Effects on Health
54
2.6.3.8 Synthetic Organic Pesticides
Since the 1940s, pesticide use has expanded because of the development of the synthetic
organic compounds. The synthetic organic pesticides (i.e., man-made, carbon-containing
chemicals) include the chemical groups; chlorinated hydrocarbons, organophosphates,
carbamates, pyrethroids, phenoxy herbicides and a number of other chemical classes.
Groups with similar chemical structure tend to be similar in their mode of action, fate in
the environment and pest control properties, but not necessarily in their level of toxicity.
Though pesticides may have different chemical structures, they can have similar modes
of actions. Their activity tends to be highly specific, and they are often harmless to non
target species.55
(a) Pyrethroids
They were developed as a synthetic version of the naturally occurring pesticide pyrethrin,
which is found in chrysanthemums. They have been modified to increase their stability in
the environment. Some synthetic pyrethroids are toxic to the nervous system.56
(b) Cypermethrin
It is a composite pyrethroid; a broad spectrum, non-cumulative insecticide and a fast-
acting neurotoxin with good contact and stomach action. It has of moderately high
toxicity to mammals and readily metabolized with immediate loss of activity.
Cypermethrin is not a plant systemic, it is readily degraded on soil or plants but has good
residual activity on inert surfaces. Cypermethrin is primarily absorbed from the
gastrointestinal tract. It may also be absorbed by inhalation of spray mist and only
minimally through the intact skin. The ADI level of cypermethrin is 0.05 mg/kg.57
55
Id. 56
Id. 57
Id.
Causes and Impact of Water Pollution and its Adverse Effects on Health
55
(c) Imidacloprid
Acetylcholine esterase enzyme inhibitor when compared to many older synthetic
pesticides imidacloprid, is only moderately toxic to mammals, including humans. It is,
however, highly toxic to other "non-target" and beneficial insect species. So, as always,
care should be taken to avoid misapplication. The ADI level of imidacloprid is 0.06
mg/kg.58
2.6.3.9 Use of Pesticides
Manufacture, trade and use of DDT are severely restricted under the Stockholm
Convention on Persistent Organic Pollutants. The use of DDT continues to be permitted
in some developing countries only in accordance with WHO recommended guidelines,
and countries are required to develop regulatory and other mechanisms to ensure that use
of DDT is restricted only to the control of endophilic vectors of the parasitic diseases
malaria and leishmaniasis.59
As per WHO estimates, pesticides lead to one million
pesticide poisoning cases and 20000 deaths globally60
2.6.4.10 Use of PesticidesiIn India
The story of pesticides usage in India is not different from other developing countries.
Usage of pesticides in India is much higher than the permissible limit because of lack of
awareness in farmers and lack of implementation of laws. Irrespective of the fact that
there are various constitutional provisions and laws for the prevention of water pollution
but the problem of water pollution is getting worse by the day.
58
Id. 59
Environmental Health Criteria 241,DDT In Indoor Residual Spraying: Human Health Aspects,
World Health Organization,2011,p.26. 60
Punjab State Council for Science and Technology, State of Environment Punjab, Chandigarh,
2007, p.97.
Causes and Impact of Water Pollution and its Adverse Effects on Health
56
TABLE NO.2.3
HEALTH EFFECTS OF SOME PESTICIDES FOUND IN GROUND WATER61
CHEMICAL
NAME CHRONIC EFFECT
ACUTE
TOXICITY
ACUTE EFFECTS AT
HIGH
CONCENTRATION
Alachlor
Growth Depression In
Laboratory Animals
High
Aldicarb None Observed Moderate
Diarrhea, Nausea,
Vomiting, Abdominal Pain,
Profuse Sweating,
Salivation And Blurred
Vision
Atrazine None Observed High
Mildly Irritating To Skin,
Eyes And Upper
Respiratory Tract
61
Retrieved from http://psep.cce.cornell.edu/facts-slides-self/facts/pes-heef-grw85.aspx on 18
January, 2014.
Causes and Impact of Water Pollution and its Adverse Effects on Health
57
Carbofuran None Observed High
Diarrhea, Nausea,
Vomiting, Abdominal Pain,
Profuse Sweating,
Salivation And Blurred
Vision
Chlorothalonil None Observed Low
DCPA None Observed Moderate
1,2,
Dichloropropane
Possible Liver And
Kidney Damage High
Acute Gastro Intestinal
Distress With Congestion
And Edema Of Lungs
Ethylene
Dibromide
(EDB)
Causes Cancer, High
Genetic Mutations
And Fatal
Deformaties. Possible
Injury To Lungs, Liver
And Kidney From
Prolonged Exposure
High
Headache, Dizziness,
Nausea, Drowsiness,
Tremors And Seizures
Oxamyl None Observed High
Diarrhea, Nausea,
Vomiting, Abdominal Pain,
Profuse Sweating,
Salivation And Blurred
Vision
Causes and Impact of Water Pollution and its Adverse Effects on Health
58
2.6.4.11 Effects of Pesticides
Pesticides have adversely affected human beings all these years. Some of these effects are
(a) Cancer
Many studies have examined the effects of pesticide exposure on the risk of cancer.
Associations have been found with: leukemia, llymophoma, brain, kidney, breast,
prostate, pancreas, liver, lung and skin cancers. This increased risk occurs with both
residential and occupational exposures. Increased rates of cancer have been found among
farm workers who apply these chemicals. A mother's occupational exposure to pesticides
during pregnancy is associated with an increases in her child's risk of leukemia, wilms‘
tumor and brain cancer.62
(b) Neurological
Strong evidence links pesticide exposure to worsened neurological outcomes. The risk of
developing Parkinson‘s disease is 70 percent greater in those exposed to even low levels
of pesticides. People with Parkinson's disease were 61percent more likely to report direct
pesticide application than were healthy relatives. Both insecticides and herbicides
significantly increased the risk of Parkinson's disease. There are also concerns that long
term exposures may increase the risk of dementia.63
The United States Environmental Protect finished a 10 year review of the
organophosphate pesticides following the 1996 Food Quality Protection Act, but did little
to account for developmental neurotoxic effects, drawing strong criticism from within the
agency and from outside researchers.64
62
Retrieved from< http://en.wikipedia.org/wiki/Health_effects_of_pesticides visited on 6th June
2012. 63
Id. 64
Id.
Causes and Impact of Water Pollution and its Adverse Effects on Health
59
(c) Reproductive Effects
Strong evidence links pesticide exposure to birth defects, fetal death and altered fetal
growth.In the United States, increase in birth defects is associated with conceiving in the
same period of the year when agrochemicals are in elevated concentrations in surface
water. Agent orange, a 50:50 mixture of 2,4,5-T and 2,4-D, has been associated with
increased birth defects in Vietnam.65
(d) Fertility
Pesticides study shows that it has an adverse affect on the fertility too. A number of
pesticides including dibromochlorophane and 2,4-D has been associated with impaired
fertility in males.66
2.6.4 Thermal Pollution
Thermal pollution results out of excessive heat generated from the thermal plants which
use water in the process of cooling their generators. This water due to contact with
excessive heat and high temperature gets polluted because of the decease in the solubility
of dissolved oxygen. The excessive heat has adverse effect in bio-chemical reactions
which are detrimental for human health and aquatic organisms.67
2.6.5 Marine Pollution
Oceans and seas are major water sources which are immensely beneficial to mankind.
Wastes from shipping fuel and oil are the main pollutants of sea water. Wastes
discharged from navigable ships cause water pollution which seriously damages the
65
Id. 66
Id. 67
Supra 34, p. 119.
Causes and Impact of Water Pollution and its Adverse Effects on Health
60
marine resources and organisms. Spilling from ships and off-shore drilling rigs also result
in marine pollution. 68
Accidents and collisions between the navigating ship results in discharge of huge amount
of oil from the tankers which pollutes the sea-water and causes irreparable damage to
marine habitat and vegetation.69
It has been the general practice that after the oil-tankers deliver the contents, the emptied
tanker is filled with sea water to clean it for being refilled again for a return trip. The
water used for cleaning is discharged in the sea which contains contaminated oil and the
water thus gets polluted.70
2.6.6 Radioactive Wastes
Today man made sources have begun to add large doses of radionuclides to the already
existing radioactive materials in water bodies to which the living organisms are
accustomed with various ill effects. Radioactive pollutants enter into water streams from
various sources such as nuclear power plants, nuclear reactors, nuclear tests, nuclear
installations, operations of power, processing of fission and fusion products etc. actually
hazards from radioactivity arise because radionuclides deposit in body organs and deliver
radiation dose. Extremely toxic radioactive Pu, Np, Cm, Bk, Cs, Zr, Ru etc. are produced
from neutron bombardment of atomic fuel. Once they find access into water bodies, they
disrupt the ecocycling process, enter into food chain and effect metabolic pathways.71
The main concern with the radioactivity is the fallout of radioactive materials from
explosions of nuclear weapons. Besides the nuclear explosions and hazards associated
with it, the other source of pollution is dumping of radioactive waste materials from the
68
Id. 69
Id. 70
Id. 71
B.K.Sharma, Water Pollution, Goel Publishing House, Meerut, Fourth Edition, 2005, p.85.
Causes and Impact of Water Pollution and its Adverse Effects on Health
61
nuclear power plants, nuclear reactors and waste from medical and research
laboratories.72
2.7 EFFECTS OF WATER POLLUTANT
Justice V.R. Krishna Iyer once remarked that, ―the unconscionable industrialisation, the
unpardonable deforestation and the inhuman extermination of living species betray an
exploitative brutality and anti-social appetite for profit and pleasure which is
incompatible with humanism and conservationism. Today a bath in Yamuna and Ganga
is a sin against bodily health, not a salvation for the soul, so polluted and noxious are
these holy waters now‖.73
When our population was limited, water supplies seemed endlessly renewable. We could
then afford to foul one water source, abandon it, and move on to another. This, however,
is no longer possible since the exponential growth rates of human population have
already reduced the availability of water to below its per capita availability.
Consequently, any further expansion of human activity will depend not only on how well
we are able to prevent the loss and contamination of the available water resources, but
also how sustainably we use what we have. Polluted water also poses a serious health
hazard to communities living nearby, and which depend on that source for most of their
activities.74
Water pollution can cause both immediate and long-term health effects.75
Acute effects
occur within hours or days of the time that a person consumes a contaminant. People can
suffer acute health effects from almost any contaminant if these are exposed to
extraordinarily high levels. In drinking water, microbes such as bacteria and viruses are
72
B.K.Sharma, Water Pollution, Goel Publishing House, Meerut, Fourth Edition, 2005, p.86. 73
Shravya K. Reddy, Water Pollution And The Law, Indian Journal Review, Vol.1, 2004, p.190. 74
Id. 75
Rene Dubos, Health Effects of Environmental Pollution, United States Environmental Protection
Agency, Washington D.C., 1973, p.8.
Causes and Impact of Water Pollution and its Adverse Effects on Health
62
the contaminants with greatest chance of reaching levels high enough to cause acute
health effects.76
2.8 DISCUSSION OF SOME ASPECTS OF WATER POLLUTION WITH
THE HELP OF TABLES
Following are some tables which are concerned with the issue of water pollution. Table
no.2 will deal with issue of ill health effects of water pollutants. Table no.3 will provide
the standards of drinking water. Table no. 4 will discuss the common diseases transmitted
to humans through contaminated drinking water.
TABLE NO. 2.4
ILL EFFECTS OF WATER POLLUTANTS77
S.NO. POLLUTANT EFFECTS OF THE POLLUTANT
1. Zinc (Zn)
Zinc is essential element for humans, animal and
plants. It is also an important cell component in
several metalloenzymes. Infants need 3–5
mg/day, adult males 15 mg/day, pregnant and
lactating females 20–25 mg Zn/day. However,
heavy doses of Zn salts (165 mg) for 26 days
causes vomiting, renal damage, cramps, etc.
76
Yael Calhoun, Water Pollution, Chelsea House Publishers, United State Of America, First
Printing, 2005, p.9. 77
Rajni Kant and Keshav Kant, Water Pollution :Management, Control And Treatment, New Age
International (P) Ltd, New Delhi, First Edition,2010,p.74.
Causes and Impact of Water Pollution and its Adverse Effects on Health
63
2. Copper (Cu)
Excess of Copper in human body (more than 470
mg) is toxic, may cause hypertension, sporadic
fever, uremia, coma. Copper also produces
pathological changes in brain tissue. However,
Cu is an important cell component in several
metalloenzymes. Lack of Cu causes anaemia,
growth inhibition and blood circulation problem.
3. Barium (Ba)
Excess of Barium (more than 100 mg) in human
body may cause excessive salivation, colic,
vomiting, diarrhoea, tremors, paralysis of
muscles or nervous system, damage to heart and
blood vessels.
4. Iron (Fe)
Iron (Fe) is one of the essential mineral for
humans and animals. Degree of absorption
depends upon solubility and stability of
compound. It is a component of blood cells and
liveral metalloenzymes. However, more than 10
mg per kg of body weight causes rapid
respiration and pulse rates, congestion of blood
vessels, hypertension and drowsiness. It
increases hazard of pathogenic organisms, as
many of them require Fe for their growth.
5. Cadmium (Cd)
Cadmium is very toxic, 50 mg may cause
vomiting, diarrhoea, abdominal pains, loss-
ofconsciousness. It takes 5-10 years for chronic
cadmium intoxication. During first phase,
discolouration of teeth, loss of sense of smell,
mouth dryness occurs. Afterwards it may cause
decrease of red blood cells, lumber pains,
disturbance in calcium metabolism, softening of
bones, fractures, skeletal deformations, damage
of kidney, hypertension, tumor formation, heart
disease, impaired reproductive function, genetic
mutation, etc.
Causes and Impact of Water Pollution and its Adverse Effects on Health
64
6.
Mercury (Hg)
Mercury is very toxic. Excess mercury in human
body (more than 100mg) may cause headache,
abdominal pain, diarrhoea, destruction of
haemoglobin, tremors, very bad effects on
cerebral functions and central nervous system,
paralysis, inactivates functional proteins, damage
of renal tissues, hyper coagulability of blood,
mimamata disease, and even death. It may cause
impairment of vision and muscles and even
coma. It disturbs reproductive and endocrine
system. Also causes insomnia, memory loss,
gum inflammation, loosening of teeth, loss of
appetite, etc.
7. Lead (Pb)
More than 400 mg of lead in human body can
cause brain damage, vomiting, loss of appetite,
convulsions, uncoordinated body movements,
helplessly amazed state, and coma. It is retained
in liver, kidney, brain, muscle, soft tissues,
bones, leads to high rate of miscarriages, affects
skin, and respiratory system, damages kidney,
liver and brain cells. Disturbs endocrine system,
causes anaemia, and long term exposure may
cause even death.
8. Arsenic (As)
Poisonous to fishes, animals and humans.
Greater than 25 mg of arsenic causes vomiting,
diarrhoea, nausea, irritation of nose and throat,
abdominal pain, skin eruptions inflammations
and even death. It binds globulin of blood
haemoglobin in erythrocytes. May cause cancer
of skin, lungs and liver, chromosomal aberration
and damage, gangrene, loss of hearing, injury to
nerve tissue, liver and kidney damage. Minor
symptoms of As poisoning, weight loss, hair
loss, nausea, depression, fatigue, white lines
across toe nails and finger nails.
9. Vanadium (V) It is very toxic, may cause paralysis.
Causes and Impact of Water Pollution and its Adverse Effects on Health
65
10. Silver (Ag)
Silver (Ag) causes pathological change in
kidney, liver and may even damage kidney. May
cause Argyria (discolouration of skin). Effects
mucous membranes and eyes. In high doses, it
may be fatal to humans.
11. Radioactivematerials/
metals/substances
These generally cause ‗Gene‘ mutation,
ionization of body fluids, chromosomnal
mutations and cancers. Destroy body cell tissue,
adversely effects reproductive system. When
mother is exposed to radiation during pregnancy,
it causes severe mental retardation and
leukaemia in infants. Radioactive metals like
heavy metals are nephrotoxic and damage
kidneys.
12. Flouride
Excess fluoride intake in body results in
progressive crippling scourge
(sponging)/fluorosis of bones, teeth. May cause
metabolic alternations in soft tissues and their
functional mechanism.
13. Selenium(Se)
Signs of Se poisoning (more than 4 mg) are
fever, nervousness, vomiting, falling of blood
pressure, causes damage to liver, kidney and
spleen, loss of nails and hair, causes blindness to
animals. Cats are most susceptible. It affects
enzyme systems and interferes with sulphur
metabolism. It can cause growth inhibition, skin
discolouration, bad teeth, psychological problem,
gastro intestinal problems, but trace amount of
Se is protective against poisoning by Hg, Cd,
Ag.
14. Chromium(Cr)
Any chromium compound is toxic but
haxavalent Cr greater than 70 mg is very toxic. It
causes cancer, anuria, nephritis, gastrointestinal
ulceration, perforation in partition of nose. It
penetrates cell membrane and badly affects
Causes and Impact of Water Pollution and its Adverse Effects on Health
66
central nervous system. Causes respiratory
trouble, lung tumors when inhaled. May cause
complications during pregnancy. It also has
adverse effects on aquatic life.
15. Manganese(Mn)
Mn is essential for mammals but in
concentration greater than 100 ppm, is toxic, and
causes growth retardation, fever, sexual
impotence, muscles fatigue, eye blindness.
16. Cobalt(Co)
High dose (27 mg or above) can cause paralysis,
diarrhoea, low blood pressure, lung irritation,
bone defects.
17. Nickel (Ni)
More than 30 mg may cause changes in muscle,
brain, lungs, liver, kidney and can also cause
cancer, tremor, paralysis and even death.
18. Boron (B)
Essential for plant growth in traces. Harmful to
crops and affects metabolic activities of plants in
higher concentration. Affects central nervous
system.
19. Alkalinity &Acidity
Permissible range of pH value if violated may
cause health problems to human and animals and
loss of productivity in agriculture.
20. Phosphate and nitrate
Soil nutrient and not toxic in low concentration.
Deplete oxygen by excess Algae production-
giving bad odour and taste of water and
detrimental to aquatic life. They are toxic for
human and animal life if concentration is beyond
permissible limits. Nitrates also cause cynosis or
blue body disease.
Causes and Impact of Water Pollution and its Adverse Effects on Health
67
21. Chlorine (Cl) Destroys plant and aquatic life and is a biocide.
22. Sulphide Gives bad odour, toxic to many aquatic
organisms and animals.
23. Salinity Very bad for soils which retain salinity. Destroys
agricultural land.
24. Oil/Grease/Oil Sludge
Petroleum products in general are very harmful
for soils, aquatic life, animal, human and plant
life. They are very toxic. Agricultural land may
suffer accumulation of oily waste affecting
aeration and fertility. Many constituents of oily
sludge are even carcinogenic and potent
immunotoxicants.
25. Surfactants and
detergents
They are toxic and harmful for aquatic life,
animals and humans. Inhibit self-purification of
water.
26. Phenols
Toxic and impart objectionable odour. Also
subdue plant growth generally. Some phenols
(nitrophenyl etc) are carcinogens.
27. Cyanides
Cyanide poses a serious health hazard. Apart
from acute toxicity and chronic toxicity, it leads
to development of iodine deficiency disorders.
Causes and Impact of Water Pollution and its Adverse Effects on Health
68
28. Pesticides/insecticides
Highly poisonous for humans and animals. Also
they lower seed germination, plays a role in
development of Parkinson‘s disease, destruction
of nerve cells in certain regions of brain resulting
in loss of dopamine which is used by nerve cells
to communicate with brain. Some of these are
physical poisons, some are protoplasmic poisons
causing liver damage, some are respiratory
poisons and some are nerve poisons.
29. Aluminium (Al) Toxic especially for brain, sometimes may lead
to Alzheimer‘s disease in humans.
Causes and Impact of Water Pollution and its Adverse Effects on Health
69
TABLE NO. 2.5
(STANDARDS OF DRINKING WATER)78
POLLUTANTS PERMISSIVE EXCESSIVE*
Physical
Turbidity (units or silica scale)
Colour (units on platinum-cobalt
scale)
Taste and odour
5 unit
5 unit
nothing
25 unit
25 unit
disagreeable
Chemical
ph
Total solids
Total hardness ( as CaCO3)
Calcium (as Ca)
Magnesium (as Mn)
Iron (as Fe)
Manganese (as Mn)
7.0-8.5
500 mg/l
300 mg/l
75 mg/l
50 mg/l
0.3 mg/l
0.1 mg/l
Less than 6.5 or greater than
9.2
1500 mg/l
600 mg/l
200 mg/l
150 mg/l
1.0 mg/l
0.5 mg/l
78
Ali Mehdi, ― Water Pollution Laws and Their Enforcement In India‖, First Edition, R. Cambray
and Co. Private Ltd., Kolkata, 2007, p.244.
Causes and Impact of Water Pollution and its Adverse Effects on Health
70
Copper (as Cu)
Zinc (as Zn)
Chlorides (as Cl)
Sulphates (as SO4)
Phenolic substances (as Phenol)
Fluorides (as F)
nitrates
1.0 mg/l
5.0 mg/l
250 mg/l
250 mg/l
0.0001 mg/l
1.0 mg/l
20 mg/l
3.0 mg/l
15.0 mg/l
1000 mg/l
400 mg/l
0.002 mg/l
2.0 mg/l
50 mg/l
Toxic substances
Arsenic (as As)
Chromium (as hexavalent)
Cyanides (as CN)
Lead (as Pb)
Selenium (as Se)
0.2 mg/l
-
-
-
-
0.2 mg/l
0.5 mg/l
0.1 mg/l
0.1 mg/l
0.05 mg/l
Radio activity
Alpha Emitters (µc/ml)
Beta Emitters(µc/ml)
-
-
10-9
10-8
Causes and Impact of Water Pollution and its Adverse Effects on Health
71
TABLE NO. 2.6
COMMON DISEASES TRANSMITTED TO HUMANS THROUGH
CONTAMINATED DRINKING WATER79
TYPES OF
ORGANISM
DISEASES EFFECTS
Bacteria
Typhoid fever
Cholera
Bacterial dysentery
Enteritis
Diarrhea, severe vomiting, enlarged spleen,
inflamed intestine; often fatal if untreated
Diarrhea, severe vomiting, dehydration; often
fatal if untreated
Diarrhea, bleeding; rarely fatal except in
infants without proper treatment
Severe stomach pain, nausea, vomiting; rarely
fatal
79
G. Tyler Miller And Scott E. Spoolman, Living In The Environment, Cengage Learning, United
States of America, 2012, p.532.
Causes and Impact of Water Pollution and its Adverse Effects on Health
72
Viruses
Infectious
Hepatitis (Type B)
Poliomyelitis
Fever, severe headache, loss of appetite,
abdominal pain, jaundice, enlarged liver,
rarely fatal, but may cause permanent liver
damage
Fever, diarrhea, backache, sore throat, aches
in limbs, can infect spinal cord, and cause
paralysis and muscle weakness
Parasitic
protozoa
Amoebic dysentery
Giardiasis
Cryptosparidium
Severe diarrhea, headache, abdominal pain,
chills, fever; if not treated can cause liver
abscess, bowel perforation, and death
Diarrhea, abdominal cramps, flatulence,
belching, fatigue
Severe diarrhea, cramps for upto three weeks,
and possible death for people with weakened
immune systems
Parasitic
worms
Schistosomiasis
Ancylostomiasis
Abdominal pain, skin rash, anaemia, chronic
fatigue, and chronic general ill health.
Severe anaemia and possible symptoms of
bronchial infections
Causes and Impact of Water Pollution and its Adverse Effects on Health
73
We can thus say that pollution of water is a very serious issue and has grave
implications for the human beings. In fact, the very survival of human beings is
dependent on availability of pollution free water with the passage of time, there has been
a huge growth in the population levels and the same has led to industrialization,
urbanisation etc. thereby putting immense pressure on the available natural resources.
The increasing population has also results in demand for more food grains, which in turn
has resulted in extensive use of fertilizers and pesticides. This excessive use of pesticides,
once a passage of time, along with industrialisation and urbanisation has led to increase
in water pollution level. We have to act and control this menace before it is too late.
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