presentation on health and safty environment by muhammad rehan tahir (research scholar)

8/3/2019 Presentation on Health and Safty Environment by Muhammad Rehan Tahir (Research Scholar)

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" I think the problem today is that turning onyour tap is an act of faith, and I'm not surethat that act of faith is particularly well-

placed If you drink from the tap, there are

several recent studies you should know aboutbecause they may change the way you thinkabout your water”

(David Ozonoff, Chairman, Environmental HealthDepartment,

Boston University)



By:

Muhammad Rehan Tahir



Contamination of drinking water sources by sewagecan occur from

raw sewage overflow

septic tanks

leaking sewer lines

land application of sludge

partially treated waste water



Sewage itself is a complexmixture and can containmany types of contaminants.

The greatest threats posed

to water resources arise fromcontamination by bacteria,nitrates, metals, tracequantities of toxic materials,

and salts.



NONPOINT SOURCES

Urban streets

Suburbandevelopment

Wastewatertreatmentplant

Rural homes

Cropland

Factory

Animal feedlot

POINTSOURCES



Good

WaterQuality

DO (ppm) at 20°C

Slightlypolluted 6.7–8

Moderatelypolluted 4.5–

6.7

Heavily

polluted 4–4.5

Gravelypolluted Below 4

8–9



Seepage overflow into drinking water sourcescan cause disease from the ingestion of microorganisms such as:

E coli

Giardia

Cryptosporidium

Hepatitis A

Helminths



Microbial Pathogens Organics

Inorganic

Radioactive Elements



Pathogens in drinking water are serious healthrisks.

Pathogens are disease-producing micro-organisms, which include bacteria such as giardia

lamblia, viruses, and parasites. They get into drinking water when the water source

is contaminated by sewage.

They can cause gastroenteritis, salmonella

infection, dysentery, shigellosis, hepatitis, andgiardiasis.



This group of contaminants includes: Trihalomthanes (THMs), which are formed when chlorine in

treated drinking water combines with naturally occurringorganic matter.

Pesticides, including herbicides, insecticides, andfungicides.

Volatile organic chemicals (VOCs), which include solvents,degreasers, adhesives, gasoline additives, and fuelsadditives.

Some of the common VOCs are: benzene, trichloroethylene(TCE), styrene, toluene, and vinyl chloride.

Possible chronic health effects include cancer, centralnervous system disorders, liver and kidney damage,reproductive disorders, and birth defects.



These contaminants include toxic metals likearsenic, barium, chromium, lead, mercury, andsilver. These metals can get into your drinkingwater from natural sources, industrial processes,and the materials used in your plumbing system.

Toxic metals are regulated in public water suppliesbecause they can cause acute poisoning, cancer,and other health effects.

Nitrate is another inorganic contaminant. The

nitrate in sewage can contaminate water. Nitratehas been associated with "blue baby syndrome" ininfants.



Radon is a radioactive contaminant that resultsfrom the decay of uranium in soils and rocks. It isusually more of a health concern when it enters ahome as a soil gas than when it occurs in water

supplies. Radon in air is associated with lungcancer.



Waterborne disease can be caused by protozoa,viruses, or bacteria, many of which areintestinal parasites

This is likely to occur where public and private

drinking water systems get their water fromsurface waters (rain, creeks, rivers, lakes etc.),which can be contaminated by infected animalsor people.

Runoff from landfills, septic fields, sewer pipes,residential or industrial developments can alsosometimes contaminate surface water.



This has been the cause of many dramaticoutbreaks of faecal-oral diseases such as choleraand typhoid.

The germs in the faeces can cause the diseases by

even slight contact and transfer. Thiscontamination may occur due to floodwaters, waterrunoff from landfills, septic fields, and sewer pipes.



Typhoid

Dysentery

Cholera

Infectious hepatitis

Amoebic dysentery

Gastroenteritis

Cryptosporidiosis



Water, sanitation and hygiene haveimportant impacts on both health anddisease.

Water-related diseases like schistosomiasis,malaria and others such as legionellosiscarried by aerosols containing certainmicro-organisms.

Water also contributes to health, forexample through hygiene.



Types of Treatment◦ Screening◦ Adsorption

◦ Aeration◦ Flocculation◦ Sedimentation◦ Filtration (including

membranes)



Type of Treatment◦ Coagulation (for better filtration)◦ Disinfection◦ Water softening◦ Oxidation

(via aeration )



Use living organisms to bring about chemicalchange



The only way to break the continuedtransmission is to improve the people’shygienic behavior and to provide them withcertain basic needs: drinking water, washing

and bathing facilities and sanitation.



Clean water is a pre-requisite for reducing thespread of water-borne diseases. It is wellrecognized that the prevalence of water-bornediseases can be greatly reduced by provision of clean drinking water and safe disposal of faeces.

Water is disinfected to kill any pathogens that maybe present in the water supply and to prevent themfrom growing again in the distribution systems.Disinfection is then used to prevent the growth of pathogenic organisms and to protect public health

and the choice of the disinfect depends upon theindividual water quality and water supply system.



As people hear about the possibility of contaminants in their drinking water, theyworry about potential health effects.

Water supplies once considered to be pure may

have various contaminants, often from naturalsources. These are usually at levels belowthose considered to be harmful.

If you are concerned, test your water. For moreinformation on water quality, testing, andtreatment, contact the Extension Center orhealth department in your county or yourphysician.



Home Water Quality and Safety. Haman, Dorata Z.and Boucher, Del B. Florida Cooperative Extension Service. University of Florida. Pub. No.14M-86.1986.

Health Effects of Drinking Water Contaminants.Stewart, Judith C., Lemley, Ann T., Hogan, SharonI. and Weismiller, Richard A. Cornell Universityand the University of Maryland. Fact Sheet2.1989.

Drinking Water: Present Problems, FutureDirections . Nutrition Clinics. Woodruff, Sandra L.Vol. 5, No. 2,1990: 1-21.

presentation on health and safty environment by muhammad rehan tahir (research scholar)

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