New presentation

1. Water Pollution due to Heavy
metals, Pesticides, Oils and
Detergents
Presented by
Joy H Jones
Roll No 08
M2 EE

2. Water Pollution

3. Water Pollution
• Water pollution may be defined as any
impairment in its native characteristics by
addition of anthropogenic contaminants to the
extent that it either cannot serve to humans for
drinking purposes and/or to support the biotic
communities, such as fish.
• Water pollution is the contamination of water
bodies such as lakes, rivers, oceans, and
groundwater by human activities

4. Heavy Metal contamination in Water Body

5. Heavy Metals
• The term heavy metal refers to any metallic
chemical element that has a relatively high
density and is toxic or poisonous at low
concentrations.

6. Heavy Metals
• Heavy metals are naturally occurring
elements that have a high atomic weight and a
density at least 5 times greater than that of
water.

7. Heavy Metals

8. HEAVY METALS
• are natural components of the Earth's crust
• they cannot be degraded or destroyed
• to a small extent they enter our bodies via food, drinking
water and air
• as trace elements, some heavy metals (e.g. copper,
selenium, zinc) are essential to maintain the metabolism
of the human body
• however, at higher concentrations they can lead to
poisoning
• heavy metal poisoning could result, for instance, from
drinking-water contamination (e.g. lead pipes), high
ambient air concentrations near emission sources, or
intake via the food chain

9. Heavy metals
• Heavy metals are dangerous because they tend
to bioaccumulate.
• Bioaccumulation means an increase in the
concentration of a chemical in a biological organism
over time, compared to the chemical's concentration
in the environment.
• Compounds accumulate in living things any time
they are taken up and stored faster than they are
broken down (metabolized) or excreted.

10. Heavy Metal
Villagers from Sahecun, in southern China,
are suffering from hideous swellings caused
by heavy metal pollution(lead) from a mine
that closed a decade ago. Huang Guiqiang,
58, said: 'The lumps over my body are
incredibly painful, and interspersed
occasionally with periods where I can't feel
anything at all in my body’

11. Heavy Metal
• Heavy metal toxicity can result in
▫ damaged or reduced mental and central nervous function,
▫ lower energy levels,
▫ Damage
 blood composition,
 lungs,
 kidneys,
 liver, and other vital organs.
▫ Long-term exposure may result in
 slowly progressing physical,
 muscular, and neurological degenerative processes that mimic Alzheimer's disease,
 Parkinson's disease,
 muscular dystrophy, and
 multiple sclerosis.
Allergies are not uncommon and repeated long-term contact with some metals or their
compounds may even cause cancer

12. Heavy Metal

13. Lead
• Exposure to inorganic lead occurs in mines and
smelters as well as welding of lead painted
metal, and in battery plants.
• Low or moderate exposure may take place in the
glass industry.
• Lead is present in fuels, on burning it will enter
the air
• Airborne lead can be deposited on soil and
water, thus reaching humans via the food
chain.

14. Lead
• In adults, inorganic lead does not penetrate the
blood–brain barrier, whereas this barrier is
less developed in children. The high
gastrointestinal uptake and the permeable
blood–brain barrier make children especially
susceptible to lead exposure and subsequent
brain damage.

15. Lead
• Acute exposure to lead is known to cause
proximal renal tubular damage.
• Long-term lead exposure may also give rise to
kidney damage

16. Lead
• IARC (International Agency Research on
Cancer) classified lead as a ‘possible human
carcinogen’ based on sufficient animal data
and insufficient human data in 1987.
• lung cancer, stomach cancer and gliomas can be
caused due to lead
• A notably serious effect of lead toxicity is its
teratogenic effect

17. Arsenic
• Arsenic is a widely distributed metalloid,
occurring in rock, soil, water and air.
• Inorganic arsenic is present in groundwater used
for drinking in several countries all over the
world (e.g. Bangladesh, Chile and China),
• Organic arsenic compounds (such as
arsenobetaine) are primarily found in fish,
which thus may give rise to human exposure

18. Man affected with Heavy metal (Arsenic)

19. Arsenic
• The latest WHO evaluation concludes that
arsenic exposure via drinking water is causally
related to cancer in the lungs, kidney, bladder
and skin, the last of which is preceded by
directly observable precancerous lesions.

20. Arsenic
• Uncertainties in the estimation of past exposures
are important when assessing the exposure–
response relationships, but it would seem that
drinking water arsenic concentrations of
approximately 100 μg/l have led to cancer at
these sites, and that precursors of skin cancer
have been associated with levels of 50–100 μg/l.

21. Cadmium
• Found in
▫ Zinc smelting,
▫ waste batteries,
▫ e-waste,
▫ paint sludge,
▫ incinerations & fuel combustion

22. Cadmium entering in Water body

23. Cadmium
• Cadmium is toxic at extremely low levels.
• In humans, long term exposure results in renal
dysfunction.
• Cadmium is also associated with bone defects,
viz; osteomalacia, osteoporosis and spontaneous
fractures, increased blood pressure and
myocardic dysfunctions.

24. Cadmium -effects

25. Mercury
The mercury compound cinnabar (HgS),
was used in pre-historic cave paintings for
red colours, and metallic mercury was
known in ancient Greece where it (as well
as white lead) was used as a cosmetic to
lighten the skin.
In medicine, apart from the previously
mentioned use of mercury as a cure for syphilis,
mercury compounds have also been used as
diuretics [calomel (Hg2Cl2)], and mercury
amalgam is still used for filling teeth in many
countries26

26. Mercury

27. Inorganic Mercury
• Acute mercury exposure may give rise to lung
damage. Chronic poisoning is characterized by
neurological and psychological symptoms, such
as tremor, changes in personality, restlessness,
anxiety, sleep disturbance and depression.
• Renal dysfunctions are also caused by mercury
exposure

28. Organic Mercury
• Methyl mercury poisoning has a latency of 1
month or longer after acute exposure, and the
main symptoms relate to nervous system
damage.
• High doses may lead to death, usually 2–4 weeks
after onset of symptoms.
•

29. Organic Mercury
• The Minamata catastrophe in Japan in the 1950s was
caused by methyl mercury poisoning from fish
contaminated by mercury discharges to the surrounding
sea.
• Minamata disease was first discovered in Minamata city
in Kumamoto, Japan, in 1956. It was caused by the
release ofmethylmercury in the
industrial wastewater from the Chisso Corporation's
chemical factory, which continued from 1932 to 1968.
• This highly toxic chemical bioaccumulated in shellfish
and fish in Minamata Bay, which, when eaten by the
local populace, resulted in mercury poisoning. While cat,
dog, pig, and human deaths continued for 36 years,

30. Minamata
• In the early 1970s, more than 10,000 persons in
Iraq were poisoned by eating bread baked from
mercury-polluted grain, and several thousand
people died as a consequence of the poisoning.
• However, the general population does not face
significant health risks from methyl mercury
exposure with the exception of certain groups
with high fish consumption.

31. Organic Mercury
• As of March 2001, 2,265 victims had been
officially recognised as having Minamata disease
(1,784 of whom had died)[2] and over 10,000 had
received financial compensation from Chisso

32. Pesticides and Water Pollution
• It is considered that more than 50% of the
water pollution of streams and rivers occur due
to leaching and mixing of chemicals from the
agriculture practices.
• The next highest source is municipal
source(about 12%).

33. Pesticides and Water Pollution
• Pesticides
▫ substances meant for attracting, seducing, and
then destroying any pest. They are a class
of biocide.
▫ are designed and developed keeping in view killing
the insects-pests in general and thus they are not
species specific

34. Pesticides

35. Pesticides
• The positive aspect of application of pesti-cides
renders enhanced crop/food productivity
and drastic reduction of vector-borne diseases.
However, their unregulated and indiscriminate
applications have raised serious concerns about
the entire environment in general and the health
of humans, birds and animals in particular.

36. Pesticides

37. Application of Pesticides

38. How pesticides reach water

40. Effects of Pesticides on Human
Health
• Human health effects are caused by
▫ 1) Skin contact: handling of pesticide products,
▫ 2) Inhalation: breathing of dust or spray and
▫ 3) Ingestion.

41. Health Impacts
• The first is the consumption of fish and
shellfish that are contaminated by pesticides;
this can be a particular problem for subsistence fish
economies that lie downstream of major agricultural
areas.
• The second is the direct consumption of pesticide-
contaminated water.
▫ . Many health and environmental protection agencies
have established “acceptable daily intake” (ADI) values
that indicate the maximum allowable pesticide daily
ingestion over a person’s lifetime without appreciable
risk to the individual.

42. Harmful effects
• The harmful efects of pesticides are
• 1) Death of the organism,
• 2) Cancers, tumours and lesions on fish and animals,
• 3) Reproductive inhibition or failure,
• 4) Suppression of immune system,
• 5) Disruption of endo- crine (hormonal) system,
• 6) Cellular and DNA damage,
• 7) Teratogenic effects (physical deformities such as
hooked beaks on birds),
• 8) Poor fish health marked by low red to white blood cell
ratio, excessive slime on fish scales and gills, etc.,
• 9) Intergenerational effects (effects are not apparent
until subsequent generations of the organism) and

43. pollution due to oil
• Oil contains many toxic compounds. Unicellular
algae and fauna are more susceptible than other
organisms. Zooplankton and crustacean larvae
are also susceptible to small oil concentrations.
Non petroleum pollutant is city sewages which
also effect on algae and marine animals.

44. Pollution due to Detergents
• Detergents are toxic for sea life as it decreases the
surface tension of water and has effect on sensitive
marine organisms. Especially phosphates in
detergent increase the toxicity. It causes
eutrophication, which is called secondary pollution.

45. What are detergents?
• Detergents are organic compounds, which have both
polar and non-polar characteristics. They tend to exist at
phase boundaries, where they are associated with both
polar and non-polar media.
• Detergents are of three types: anionic, cationic, and
non-ionic.
• Anionic and cationic have permanent negative or
positive charges, attached to non-polar (hydrophobic) C-
C chains. Non-ionic detergents have no such permanent
charge; instead, they have a number of atoms which are
weakly electropositive and electronegative. This is due to
the electron-attracting power of oxygen atoms.

46. Detergents
• There are two kinds of detergents with different
characteristics: phosphate detergents
and surfactant detergents. Detergents that
contain phosphates are highly caustic, and
surfactant detergents are very toxic. The
differences are that surfactant detergents are
used to enhance the wetting, foaming, dispersing
and emulsifying properties of detergents.
Phosphate detergents are used in detergents to
soften hard water and help suspend dirt in
water.

47. What do we use them for?
•
Detergents are very widely used in both industrial
and domestic premises like soaps and detergents to
wash vehicles.
• The major entry point into water is via sewage works
into surface water.
• They are also used in pesticide formulations and for
dispersing oil spills at sea. The degradation of
alkylphenol polyethoxylates (non-ionic) can lead to
the formation of alkylphenols (particularly
nonylphenols), which act as endocrine disruptors.

48. • High phosphate detergents such as tri-sodium
phosphate (TSP) can be purchased at some paint
and hardware stores. Regular cleaning with high
phosphate detergents has proven to be effective
in reducing lead dust. Lead dust accumulates in
window wells and around doors or any other
high friction surfaces.

49. What occurs if detergents show up
in freshwaters?
•
Detergents can have poisonous effects in all types of
aquatic life if they are present in sufficient quantities,
and this includes the biodegradable detergents. All
detergents destroy the external mucus layers that
protect the fish from bacteria and parasites; plus they
can cause severe damage to the gills.
• Most fish will die when detergent concentrations
approach 15 parts per million. Detergent
concentrations as low as 5 ppm will kill fish eggs.
Surfactant detergents are implicated in decreasing the
breeding ability of aquatic organisms.

50. Detergents
• Detergents also add another problem for aquatic
life by lowering the surface tension of the
water. Organic chemicals such as pesticides and
phenols are then much more easily absorbed by
the fish. A detergent concentration of only 2
ppm can cause fish to absorb double the amount
of chemicals they would normally absorb,
although that concentration itself is not high
enough to affect fish directly.

51. Detergents
• Phosphates in detergents can lead to freshwater
algal blooms that releases toxins and deplete
oxygen in waterways. When the algae
decompose, they use up the oxygen available for
aquatic life.
.

52. Detergents
• The main contributors to the toxicity of detergents
were the sodium silicate solution and the
surfactants-with the remainder of the components
contributing very little to detergent toxicity.
• The potential for acute aquatic toxic effects due to
the release of secondary or tertiary sewage effluents
containing the breakdown products of laundry
detergents may frequently be low.
• However, untreated or primary treated effluents
containing detergents may pose a problem. Chronic
and/or other sublethal effects also pose a problem

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