Environmental pollution

Environmental ScienceUnit:3.1

Definition

• Any undesirable change in the physical, Chemical or biological characteristics of any components of the environment (air, water, soil) which can cause harmful effects of various forms of life or property.

• Pollution is the introduction of contaminants into the natural environment that cause adverse change

There are various types of pollution :

• Air pollution

• Water pollution

• Noise pollution

• Land pollution

• Thermal pollution

1

Causes of Environmental pollution

(1) Natural(volcanic eruption, forest fire)

(2) Man Made

Causes of man made environmental pollution are:

• Rapid industrialization

• Population growth

• Unplanned urbanization

Water pollution• Water pollution can be defined as alteration in physical,

chemical or biological characteristics of water through natural or human activities making it unsuitable for it’s designated use.

• It can be also defined as the presence in water, of some foreign substances or impurities (organic, inorganic, biological Radiological) in such quantity so as to constitute a health hazard by lowering the

water quality and making it unfit

for use.

2

Signs of polluted water

• Bad taste of drinking water

• Offensive odours of rivers, lakes and oceans

• Decrease in numbers of fish in fresh water and sea water

• Oil and grease floating on the surface

• Unchecked growth of aquatic weeds

Sources of water pollution

• Sources of water pollution can be Classified as

(a) Point sources:

the source which can be identified as a single location are called point sources

Examples are as follows

• Industrial effluent

• Power plants

• Sewage discharge etc.

It is possible to minimize the water pollution from the point sources if the waste water is collected and is given some treatment before it is discharged into a water body.

(B) Non point sources

• Non point sources also called as Area or diffuse sources :

The discharge from this sources is not at any particular site, rather this sources are scattered, which individually or collectively pollute the water.

Examples are as follows:

• Surface runoff from agricultural fields

• Overflowing small drains

• Rain water sweeping roads and fields

• Atmospheric deposition etc.

Point and Nonpoint Sources

NONPOINT SOURCES

Urban streets

Suburban development

Wastewater treatment plant

Rural homes

Cropland

Factory

Animal feedlot

POINT SOURCES

Fig. 22-4 p. 494

3

Major sources of surface water pollution are

• Sewage: discharge of sewers and drains.• industrial effluents from different industries• Synthetics detergents used for washing and cleaning• Agro chemical like fertilizers containing nitrates and phosphate and pesticides used in the agricultural fields which comes in the runoff from the agricultural land• Oil spillage during drilling and shipment • Waste heat from industrial discharge increases the temperature of the waste bodies.

Major sources of ground water pollution are

• Septic tank• Deep well injection of industrial effluents• Mines etc

Classification of water pollutants

It can be classified into the following categories

a. Suspended matterb. Natural organic pollutants (sewage and effluent from some industries

like dairy, food processing etc.). They are also called as oxygen demanding waste

c. Synthetic organic compounds (Detergents, fertilizers, Pesticides)d. Pathogens (Bacterias,viruses, protozoa, worms)e. Inorganic pollutants (acids ,alkali ,metals)f. Thermal pollutants or thermal dischargeg. Radioactive pollutantsh. Sediments

Water pollutants can also be classified in general on the basis of physical nature as:

Suspended particles :• This particles have diameter of more than 1 micrometer and are the largest in polluted water.• They are large enough to settle out of water quickly and may be retained on the filterExamples :leaves ,soil particles, oil and grease etc.

Colloidal particles :• These particles are so small that their settling rate is insignificant.• They cannot be removed by plain sedimentation• They are charged particles, charged can be negative or positive but mostly in water colloidal particles are of negative charge

Dissolved matter :• This pollutants gets dissolved in the water and does make water turbid, such matter does not settled out or nor can be removed by filter • It can be organic or inorganic

Effects of water pollutants

Effects of various types of water pollutants are as follows :

Oxygen demanding waste (biodegradable organic waste ) • Organic matter which reaches the water bodies is decomposed by microorganisms present in water.• For this oxygen dissolved in water is used.

ORGANIC MATTER + DO (O2) + BACTERIA CO2 + H2O

Biochemical oxygen demand (BOD)• It is used to as a measure to find out the amount of biodegradable matter in the water.• It is defined as amount of oxygen required by the bacteria to decompose the biodegradable organic matter under aerobic condition.• The saturate value of DO in water is in the order of 8-15 mg/l .• Optimum Do required for healthy fish and other aquatic life is about 5-8 mg/l.•Due to degradation of waste DO level gets reduced • If DO drops below 4mg/l fish and other aquatic life is threatened and in extreme cases killed.

• Many waste water especially sewage contains many pathogenic micro organism which are usually contained if faeces and urine of the infected persons • Water borne diseases like cholera, dysentery, typhoid, bacillary dysentery are caused due to pathogen present in water.

Pathogens

Nitrogen and phosphorus Compounds( Nutrients)

• Addition of compounds containing nitrogen and phosphorus helps in growth of algae and other plants.• These compounds are nutrients for growth of algae and other plants.• When there concentration is high it causes rapid growth causing algal bloom.• It covers up the water surface and prevent entry of sunlight into water bodiesAquatic plants along with algae thus die; the bacteria present in water now decompose all these dead plants• The decayed organic matter adds unwanted color, odor and taste to waterIt also reduced DO of water and leads to death of fish and other aquatic animalsThis process of nutrients enrichment is known as Eutrophication

Toxic Compounds

pollutants such as heavy metals, pesticides, cyanides and many other organic and inorganic compounds are harmful to aquatic organisms some of the substances like pesticides, methyl mercury etc move in to the bodies of organisms from medium in which these organism live. Substance like DDT are not water soluble and have affinity for body lipid.These substance tend to accumulate in organisms body .This process is called bio accumulation. The concentration of these toxic substances builds up at successive levels of food chain. These process is called Biomagnifications. Minamata Disease occurs due to consumption of methyl mercury contaminated fish. Nitrate more than 45mg/l causes blue baby disease in infants Excess fluoride causes fluorosis

Bioaccumulation is the “build-up of chemicals in living organisms”.The chemical accumulates because it does not break down easily(decomposers can’t break them down)

Biomagnification is the process where chemicals accumulate AND become more concentrated at each trophic level of the food chain.

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Suspended matter

• Biodegradable suspended matter causes DO depletion

• It reduced light penetration there by reducing photosynthesis and a corresponding loss in food production

• Providing adsorption sites for harmful chemicals or biological organisms which can effect flora and fauna of stream

Thermal dischargeWater is used for dissipation of waste heat in power plant and industries

This heated water is subsequently discharged into water bodies

Increase temperature of water has following effects:

• Increase Biological activities

• Cause death of some heat sensitive organisms

• DO concentration decrease this together with increased biological activities at high temperature may result into anaerobic conditions. Resulting in bad odour

• Growth of Algae increases

• Toxicity of pollutants increase with increase in temperature

EUTROPHICATION

5

When lakes, streams and estuaries are overfertilized, excessive production of aquaticorganic matter can become a water qualityproblem and as a result the Eutrophication process can be enhanced!

6

Eutrophication is a natural process!

However, humans in their everyday activities can exacerbate the process:

Point sources (can locate the cause)

• Sewage treatment plant discharges

• Storm sewer discharges

• Industrial discharges

Non-point sources (can’t locate the cause, it’s everywhere)

• Atmospheric deposition

• Agricultural runoff (fertilizer, soil erosion)

• Septic systems

Eutrophication: a process by which a body ofwater progresses from its origin to itsextinction. This process happens in stages.

BEFORE EUTROPHICATION

AFTER EUTROPHICATION

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LACK OF OXYGEN

GROWTH OF BACTERIA

DEATH OF PLANTS

SUFFOCATION

GROWTH OF PLANTS

ADDITION OF NITRATES

Eutrophication process in 6 stages

fertiliserssewage

(liquid domesticand industrial waste)

mineralsesp. nitrates

mineralsesp. phosphates

eutrophication

algal bloom

competitionfor light

consumers can't consume fast enough

dead plants dead algae

detritus

more decomposers

use up oxygenby aerobic respiration

(increased BOD)

aerobes die(invertebrates,

fish, etc)

anaerobic bacteriathrive. ReleaseNH , CH , H S4 4 2

org

anic

mate

rial

Th

e p

roce

ss o

fE

utr

op

hic

ati

on

8

fertiliserssewage

(liquid domesticand industrial waste)

mineralsesp. nitrates

mineralsesp. phosphates

eutrophication

algal bloom

competitionfor light

consumers can't consume fast enough

dead plants dead algae

detritus

more decomposers

use up oxygenby aerobic respiration

(increased BOD)

aerobes die(invertebrates,

fish, etc)

anaerobic bacteriathrive. ReleaseNH , CH , H S4 4 2

org

anic

mate

rial

The process of Eutrophication cont.

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Biochemical Oxygen Demand (BOD).

This measures the rate of oxygen consumption by a sample of water, and therefore gives a good indication of eutrophication. A high BOD means lots of organic material and aerobic microbes, i.e. eutrophication

LACK OF OXYGEN

GROWTH OF BACTERIA

DEATH OF PLANTS

SUFFOCATION

GROWTH OF PLANTS

ADDITION OF NITRATES

Eutrophication process in 6 stages

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Before increases in nutrients:

11

Acceleration of Eutrophication :

12

Results of eutrophication :

13

14

15

Photo 1: Algal bloom in a lake.

Photo 1: Algal bloom in a lake. 16

Photo 2: Overgrowth of floating aquatic plants.17

Photo 23: Lake Biwa, the largest lake in Japan during summer time showing overgrowth of aquatic plants.

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Photo 4: Fish mortality due to lack of oxygen in an Indonesian lake.

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Put in order the stages of Eutrophication!

LACK OF OXYGEN

GROWTH OF BACTERIA

DEATH OF PLANTS

SUFFOCATIONGROWTH OF PLANTS

ADDITION OF NITRATES

CONTROLL OF WASTE WATER

A wastewater treatment plant (WWTP) or wastewater treatment

works is an industrial structure designed to remove biological or

chemical waste products from water, thereby permitting the treated

water to be used for other purposes.

Functions of wastewater treatment plants include:

• Agricultural wastewater treatment – treatment and disposal of

liquid animal waste, pesticide residues etc. from agriculture.

• Sewage treatment – treatment and disposal of human waste, and

other household waste liquid from toilets, baths, showers, kitchens,

and sinks.

• Industrial wastewater treatment – the treatment of wet wastes from

manufacturing industry and commerce including mining, quarrying

and heavy industries.

Primary: removes 60% of solids and 30-40% oxygen demanding wastes (physically)

Secondary: uses biological processes to remove up to 90% of biodegradables

Tertiary: advanced techniques

Disinfection: chlorine, ozone, UV

What is not taken out???

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Sewage treatment is the process of removing contaminants from wastewater, including household sewage and runoff (effluents).• It includes physical, chemical, and biological processes to remove physical, chemical and biological contaminants.

Stages of Sewage treatment plant

1. Pretreatment

Pretreatment removes all materials that can be easily collected from the raw sewage before they damage or clog the pumps and sewage lines of primary treatment clarifiers. Objects that are commonly removed during pretreatment include trash, tree limbs, leaves, branches, and other large objects.

The influent in sewage water passes through a bar screen to remove all large objects like cans, rags, sticks, plastic packets etc. carried in the sewage stream

Grit removal

Pretreatment may include a sand or grit channel or chamber, where the velocity of the incoming sewage is adjusted to allow the settlement of sand, grit, stones, and broken glass. These particles are removed because they may damage pumps and other equipment. For small sanitary sewer systems, the grit chambers may not be necessary, but grit removal is desirable at larger plants.

• Flow equalization

• Fat and grease removalIn some larger plants, fat and grease are removed by passing the sewage through a small tank where skimmers collect the fat floating on the surface. Air blowers in the base of the tank may also be used to help recover the fat as a froth. Many plants, however, use primary clarifiers with mechanical surface skimmers for fat and grease removal.

2 . Primary treatment

In the primary sedimentation stage, sewage flows through large tanks, commonly called "pre-settling basins", "primary sedimentation tanks" or "primary clarifiers". The tanks are used to settle sludge while grease and oils rise to the surface and are skimmed off. Primary settling tanks are usually equipped with mechanically driven scrapers that continually drive the collected sludge towards a hopper in the base of the tank where it is pumped to sludge treatment facilities. Grease and oil from the floating material can sometimes be recovered for saponification.

Equalization basins may be used for temporary storage of diurnal or wet-weather flow peaks. Basins provide a place to temporarily hold incoming sewage during plant maintenance and a means of diluting and distributing batch discharges of toxic or high-strength waste which might otherwise inhibit biological secondary treatment (including portable toilet waste, vehicle holding tanks, and septic tank pumpers).

3. Secondary treatment

Secondary treatment is designed to substantially degrade the biological content of the sewage which are derived from human waste, food waste, soaps and detergent. The majority of municipal plants treat the settled sewage liquor using aerobic biological processes. To be effective, the biota require both oxygen and food to live. The bacteria and protozoa consume biodegradable soluble organic contaminants (e.g. sugars, fats, organic short-chain carbon molecules, etc.) and bind much of the less soluble fractions into floc.

• Activated sludge

These mostly carbonaceous dissolved solids undergo aeration to be broken down and biologically oxidized or converted to carbon dioxide. Likewise, nitrogenous dissolved solids (amino acids, ammonia, etc.) are also oxidized (=eaten) by the floc to nitrites, nitrates, and, in some processes, to nitrogen gas through denitrification.

Interestingly, like most living creatures, activated sludge biota can get sick. This many times takes the form of the floating brown foam, Nocardia. While this so-called 'sewage fungus' (it isn't really a fungus) is the best known, there are many different fungi and protists that can overpopulate the floc and cause process upsets. Additionally, certain incoming chemical species, such as a heavy pesticide, a heavy metal (e.g.: plating company effluent) load, or extreme pH, can kill the biota of an activated sludge reactor ecosystem. Such problems are tested for, and if caught in time, can be neutralized.

While denitrification is encouraged in some treatment processes, in many suspended aeration plants denitrification will impair the settling of the floc and lead to poor quality effluent.In either case, the settled floc is both recycled to the inflowing primary effluent to regrow, or is partially 'wasted' (or diverted) to solids dewatering, or digesting, and then dewatering.

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DisinfectionThe purpose of disinfection in the treatment of waste water is to substantially reduce the number of microorganisms in the water to be discharged back into the environment for the later use of drinking, bathing, irrigation, etc.

4. Tertiary treatmentThe purpose of tertiary treatment is to provide a final treatment stage to further improve the effluent quality before it is discharged to the receiving environment (sea, river, lake, wet lands, ground, etc.). More than one tertiary treatment process may be used at any treatment plant. If disinfection is practised, it is always the final process. It is also called "effluent polishing.“Sand filtration removes much of the residual suspended matter. Filtration over activated carbon, also called carbon adsorption, removes residual toxins

Technological Approach: Sewage Treatment

Physical and biological treatment

Fig. 22-16 p. 511

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WATER QUALITY STANDARD

Indian Standard

Drinking Water - Specification

IS 10500 : 1991

Technical Terms

• BIS (Bureau of Indian Standards)

• Desirable limits

• Permissible limit

• PPM

• Hazen Units

Colour, Hazen Units

IS 10500-1991 Desirable : 5 Hz. , Permissible : 25 Hz.

Risks or effects Visible tint, acceptance decreases

SourcesTannins, Iron, Copper, Manganese

Natural deposits

Treatment Filtration, Distillation, Reverse osmosis, Ozonisation

Odour

IS 10500-1991 Unobjectionable

Risks or effects Rotten egg, Musty, Chemical

SourcesChlorine, Hydrogen sulphide, Organic matter, Septic

contamination, Methane gas

Treatment Activated carbon, Air stripping, oxidation, Filtration

pH

IS 10500-

1991

Desirable :6.5 – 8.5, Permissible

:No relaxation

Risks or

effects

Low pH - corrosion, metallic

taste

High pH – bitter/soda taste,

deposits

Sources Natural

Treatment

Increase pH by soda ash

Decrease pH with white vinegar

/ citric acid

Total Dissolved Solids (TDS)

IS 10500-1991 Desirable : 500 mg/l , Permissible : 2000 mg/l

Risks or effectsHardness, scaly deposits, sediment, cloudy colored water,

staining, salty or bitter taste, corrosion of pipes and fittings

Sources

Livestock waste, septic system

Landfills, nature of soil

Hazardous waste landfills

Dissolved minerals, iron and manganese

Treatment Reverse Osmosis, Distillation, deionization by ion exchange

http://www.inspectapedia.com/plumbing/Galv

Hardness

IS 10500-1991 Desirable :300 mg/l , Permissible : 600 mg/l

Risks or effects Scale in utensils and hot water system, soap scums

SourcesDissolved calcium and magnesium from soil and aquifer

minerals containing limestone or dolomite

Treatment Water Softener Ion Exchanger , Reverse Osmosis

Alkalinity

IS 10500-1991 Desirable : 200 mg/l , Permissible : 600 mg/lit

Risks or effects

Low Alkalinity (i.e. high acidity) causes

deterioration of plumbing and increases the

chance for many heavy metals in water are

present in pipes, solder or plumbing fixtures.

SourcesPipes, landfills

Hazardous waste landfills

Treatment Neutralizing agent

Iron

IS 10500-1991 Desirable : 0.3 mg/l , Permissible : 1.0 mg/l

Risks or effectsBrackish color, rusty sediment, bitter or metallic taste, brown-

green stains, iron bacteria, discolored beverages

SourcesLeaching of cast iron pipes in water distribution systems

Natural

Treatment Oxidizing Filter , Green-sand Mechanical Filter

Manganese

IS 10500-1991 Desirable : 0.1 mg/l , Permissible : 0.3 mg/l

Risks or effects

Brownish color, black stains on laundry and

fixtures at .2 mg/l, bitter taste, altered taste of

water-mixed beverages

SourcesLandfills

Deposits in rock and soil

TreatmentIon Exchange , Chlorination, Oxidizing Filter , Green-sand

Mechanical Filter

Sulphate

IS 10500-1991 Desirable : 200 mg/l, Permissible : 400 mg/l

Risks or effectsBitter, medicinal taste, scaly deposits, corrosion, "rotten-

egg" odour from hydrogen sulphide gas formation

Sources

Animal sewage, septic system, sewage

By-product of coal mining, industrial waste

Natural deposits or salt

Sulphate Treatment Ion Exchange , Distillation , Reverse Osmosis

SO4

Nitrate

IS 10500-1991 Desirable : 45 mg/l, Permissible : 100 mg/lit

Risks or effects Methemoglobinemia or blue baby disease in infants

Sources

Livestock facilities, septic systems, manure lagoons,

Household waste water,

Fertilizers,

Natural Deposits,

Treatment Ion Exchange, Distillation, Reverse Osmosis

NO3-

Chloride

IS 10500-1991 Desirable : 250 mg/l , Permissible : 1000 mg/l

Risks or effectsHigh blood pressure, salty taste, corroded pipes, fixtures and

appliances, blackening and pitting of stainless steel

Sources

Fertilizers

Industrial wastes

Minerals, seawater

Treatment Reverse Osmosis , Distillation, Activated Carbon

Cl

Fluoride

IS 10500-1991 Desirable : 1.0 mg/l, Permissible : 1.5 mg/l

Risks or effects Brownish discoloration of teeth, bone damage

SourcesIndustrial waste

Geological

TreatmentActivated Alumina, Distillation, Reverse Osmosis, Ion

Exchange

Arsenic

IS:10500-1991 Desirable: 0.05 mg/l Permissible: No relaxation

Risks or effectsWeight loss; Depression; Lack of energy; Skin and nervous

system toxicity

Sources

Previously used in pesticides (orchards)

Improper waste disposal or product storage of glass or

electronics, Mining

Rocks

TreatmentActivated Alumina Filtration, Reverse Osmosis, Distillation,

Chemical Precipitation, Ion exchange, lime softening

Chromium

IS 10500-1991 Desirable : 0.05 mg/l, Permissible : No relaxation

Risks or effects

Skin irritation, skin and nasal ulcers, lung tumors,

gastrointestinal effects, damage to the nervous system and

circulatory system, accumulates in the spleen, bones, kidney

and liver

Sources

Septic systems

Industrial discharge, mining sites

Geological

Treatment Ion Exchange, Reverse Osmosis, Distillation

Copper

IS 10500-1991 Desirable : 0.05 mg/l, Permissible : 1.5 mg/l

Risks or effects

Anemia, digestive disturbances, liver and kidney damage,

gastrointestinal irritations, bitter or metallic taste; Blue-green

stains on plumbing fixtures

Sources

Leaching from copper water pipes and tubing, algae

treatment

Industrial and mining waste, wood preservatives

Natural deposits

Treatment Ion Exchange, Reverse Osmosis, Distillation

Cyanide

IS 10500-1991 Desirable : 0.05 mg/l, Permissible : No relaxation

Risks or effects Thyroid, nervous system damage

Sources

Fertilizer

Electronics, steel, plastics mining

Treatment Ion Exchange, Reverse Osmosis, Chlorination

Lead

IS 10500-1991 Desirable : 0.05 mg/l, Permissible : No relaxation

Risks or effects

Reduces mental capacity (mental retardation), interference with

kidney and neurological functions, hearing loss, blood

disorders, hypertension, death at high levels

Sources

Paint, diesel fuel combustion

Pipes and solder, discarded batteries, paint, leaded gasoline

Natural deposits

TreatmentIon Exchange, Activated Carbon , Reverse Osmosis,

Distillation

Brain Nerve Damage

Hearing Problems

Digestive Issues

Stunted Growth

Mercury

IS 10500-1991 Desirable : 0.001 mg/l, Permissible : No relaxation

Risks or effectsLoss of vision and hearing, intellectual deterioration, kidney

and nervous system disorders, death at high levels

Sources

Fungicides

Batteries, fungicides

Mining, electrical equipment, plant, paper and vinyl chloride

Natural deposits

Treatment Reverse Osmosis, Distillation

Zinc

IS 10500-1991 Desirable :5 mg/l, Permissible : 15 mg/l

Risks or effects Metallic taste

SourcesLeaching of galvanized pipes and fittings, paints, dyes

Natural deposits

TreatmentIon Exchange Water Softeners, Reverse Osmosis,

Distillation

Total Coliform Bacteria

IS 10500-199195% of samples should not contain coliform in 100 ml

10 coliform / 100ml

Risks or effects Gastrointestinal illness

Sources

Livestock facilities, septic systems,

Household waste water

Naturally occurring

Treatment Chlorination , Ultraviolet, Distillation, Iodination

E.coliform Bacteria

IS 10500-1991 Nil / 100ml

Risks or effects Gastrointestinal illness

Sources

Livestock facilities, septic systems, manure lagoons

Household waste water

Naturally occurring

Treatment Chlorination , Ultraviolet, Distillation, Iodination

HEALTH EFFECTS OF CHEMICAL PARAMETERS

Parameter BIS Guideline value (maximum allowable)

General & Health effect

Total dissolved solids

2000 mg/L Undesirable taste; gastro intestinal irritations; corrosion or incrustation

PH 6.5-8.5 Affects mucous membrane; bitter taste; corrosion; affects aquatic life

Alkalinity 600 mg/L Boiled rice turns yellowish

Hardness 600 mg/L Poor lathering with soap; deterioration of the quality of clothes; scale forming; skin irritation; boiled meat and food become poor in quality

Calcium 200 Poor lathering and deterioration of the quality of clothes; incrustation in pipes; scale formation

Magnesium 100 Poor lathering and deterioration of clothes; with sulfate laxative

Iron 1.0 Poor or sometimes bitter taste, color and turbidity; staining of clothes materials; iron bacteria causing slime

Manganese 0.3 Poor taste, color and turbidity; staining; black slime

HEALTH EFFECTS OF CHEMICAL PARAMETERS

ParameterBIS Guideline value (maximum allowable)

General & Health effect

Aluminum 0.2 Neurological disorders; Alzheimer's disease

Copper 1.5 Liver damage; mucosal irritation, renal damage and depression; restricts growth of aquatic plants

Zinc 15 Astringent taste; opalescence in water; gastro intestinal irritation; vomiting, dehydration, abdominal pain, nausea and dizziness

Ammonia - Indicates pollution; growth of algae

Nitrite - Forms nitrosoamines which are carcinogenic

Nitrate 100 Blue baby disease (methemoglobineamia); algal growth

Sulfate 400 Taste affected; laxative effect; gastro intestinal irritation

Chloride 1000 Taste affected; corrosive

Fluoride 1.5 Dental and skeletal fluorosis; non-skeletal

HEALTH EFFECTS OF CHEMICAL PARAMETERS

ParameterBIS Guideline value (maximum allowable)

General & Health effect

Phosphate - Algal growth

Arsenic 0.05 Toxic; bio-accumulation; central nervous system affected; carcinogenic

Mercury 0.001 Highly toxic; causes 'minamata' disease-neurological impairment and renal disturbances; mutagenic

Cadmium 0.01 Highly toxic; causes 'itai-itai' disease-painful rheumatic condition; cardio vascular system affected; gastro intestinal upsets and hyper tension

Lead 0.05 Causes plumbism-tiredness, lassitudes, abdominal discomfort, irritability, anaemia; bio-accumulation; impaired neurological and motor development, and damage to kidneys

Chromium 0.05 Carcinogenic; ulcerations, respiratory problems and skin complaints

Pesticide 0.001 Affects central nervous system

Detergent - Undesirable foaming

Reference/Sources1. https://lh4.ggpht.com/XhF7qVcqi75gETCGikf5OqKmqRgoOOvhEvq0V0NYeZ9_-

cLiefekabwNoMx0n_-7R7tWaQc=s112

2. https://lh3.ggpht.com/l86mPoiiBxoHZmcNUQvtp0rXy8UJYyiNSGP9obboAbu6YuGoewDsn3_QoIpKAw2xpvx53Zw=s144

3. https://lh4.ggpht.com/vv2KOlCrMLOf9BidePDG-j_Ol0o7ULir3lDDHdka0U-SUxPjMaHdCG935VPSxHEk2x_rMA=s162

4. https://lh4.ggpht.com/sOeW_pE32T9j6bGEkrWoZtgnmEmNcUY96twsr5xvp7zUTaWhOb2LrNi88KiXlkVP_vurIRw=s85

5. https://lh3.ggpht.com/JXz_V5_x7cIlhakpgkcq5tu6Is6jXt9A8VXL19Y8ePq_E8ktrZesfY5WkFoJyRAECKFk=s136

6. https://lh4.ggpht.com/S8dSJxWxxtPZhdf2tLHziq4nIlXIQpW4PmH50maQx3PKVtcGevYCWd3N4dffxdSMhzsK=s85

7. https://lh6.ggpht.com/TLSEKDi3y1LI6UAu5OkT7G2R73ozgry94ZZmBQaNniuWGdFbJOMIXtlgd47Plp0epu6AfBY=s128

8. https://lh6.ggpht.com/aq34LXa7D59Rm34cSq8hcVFTBWRiAaG-xzDpVKlr7nV-NBdMCnGv2d5N-jxs8eAvU9nNrQ=s85

9. https://lh6.ggpht.com/ZhPy43cPAtB6oXeSe33TBXz1MQDT1E_SoGMmAUuorGeaBC2uqTnBuJ0IYi4NNFKSnqnM-Ko=s106

10. https://lh4.ggpht.com/c-tbMD2VExTEG9Gkf0cFgf-1I-gowOqtB6i50r2gmVWj_VDLkQu09WqEnQsKSsdlGxAksQ=s122

11. https://lh4.ggpht.com/-X9WcQxfVCWo70BCREMDAHeAg9CitB7Gxc18Fu_VLFSdb7fgP6ycK9Wbqp02Y26PkzA8=s144

12. https://lh6.ggpht.com/Rw461P0BeWowFuHNB3qfN5U-McBm6sIiDFjpQ2q7XKI4__cUTiE5_-A4bm6sI9876_B_rg=s144

13. https://lh6.ggpht.com/QVy1lZ2RqmRnaFfsdUrrSCP7gkEK2gTvzkBdwBpyoGwYNmGP5yDlydjUe_44DOYyBsNRFQ=s147

14. https://lh5.ggpht.com/MYbEOt8FNLEg_BbVOVQdUnDxu7MF03gXzY5vUSbOpg8azyz1znfBjYpSP2WnccIYKflX=s99

15. https://lh5.ggpht.com/rRGblAJ6mvnK91iw2EI-YnH0TCCP5FeWWymnswNh6NAoj_9Gsh_n3XEJfl4e2lSOgYMC=s170

16. https://lh5.ggpht.com/uKOrj2iAYD1YtiSI-M_74SLh-49auuloZ2iUb4BztqVXnRH4_jst0L8auust41rcomdGog=s122

17. https://lh5.ggpht.com/tO3NmsW65lx00Ek1DWGAkU4AJiL2k8XaAtmZAfNlzOC0h4SQCi753s7Af6PaAsHD0iMhc6w=s123

18. https://lh6.ggpht.com/h84-Wlz3KSIGB7vgVqTZcn54l_eRq9hBuwFxW5Q283b_3Wyrhrp1D7emszNJVb_AfojEUw=s120

19. https://lh4.ggpht.com/7vkeq3ecZciBJ5mXO_Uy4Fw-K5l1tcfV-C0SHb5jyEL8pu-_tDpOIpE2Eg9dBTD0zCN-WQ=s85

20. https://lh4.ggpht.com/8kTMNilzVDs1gLGtSUdPhbhMlQYQB3SCbFrK0IMFL-h3x83fxTHFD7zPxwcvDOMKmDzLdQ=s131

21. https://lh6.ggpht.com/fCleUI4vIXu7zbNHuFUsnddlTm1d6h-r9gQGuCGvReFwVG3bSxOJbBIs85alMlhYkZ5z=s117

22. https://lh6.ggpht.com/OYq1NXaJbyGVt8pT6fFm8lsqC0DFnOaLamv0R9WBIY7-uejxtKgShh4AX53zvVGl-WfpOBE=s113

23. https://lh4.ggpht.com/Ar3QIH8-FTsuKolU-Gh711vf855sV4Rhw4ybVPJLdh2iIbhK0cecgweomUHvmAZiyP3Z=s105

Book/Web ResourcesEnvironmental Pollution: Causes, Effects & Control by K.C Agrawal