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please do give a sketch of seminar on the topic : 1 international standards for drinking water 2 soil pollution 3 pesticides 4 waste management please do help me as soon as you can .........better on 10 th january 2014

1  International standards for drinking water

Parameters for drinking water quality typically fall under three categories:

    physical
    chemical
    microbiological.

Physical and chemical parameters include heavy metals, trace organic compounds, total suspended solids (TSS), and turbidity.

Microbiological parameters include Coliform bacteria, E. coli, and specific pathogenic species of bacteria (such as cholera-causing Vibrio cholerae), viruses, and protozoan parasites.

Chemical parameters tend to pose more of a chronic health risk through buildup of heavy metals although some components like nitrates/nitrites and arsenic can have a more immediate impact. Physical parameters affect the aesthetics and taste of the drinking water and may complicate the removal of microbial pathogens.

Originally, fecal contamination was determined with the presence of coliform bacteria, a convenient marker for a class of harmful fecal pathogens. The presence of fecal coliforms (like E. Coli) serves as an indication of contamination by sewage. Additional contaminants include protozoan oocysts such as Cryptosporidium sp., Giardia lamblia, Legionella, and viruses (enteric).[34] Microbial pathogenic parameters are typically of greatest concern because of their immediate health risk.

Throughout most of the world, the most common contamination of raw water sources is from human sewage and in particular human faecal pathogens and parasites. In 2006, waterborne diseases were estimated to cause 1.8 million deaths each year while about 1.1 billion people lacked proper drinking water.[35] It is clear that people in the developing world need to have access to good quality water in sufficient quantity, water purification technology and availability and distribution systems for water. In many parts of the world the only sources of water are from small streams often directly contaminated by sewage.

The World Health Organisation (WHO) guidelines include the following recommended limits on naturally occurring constituents that may have direct adverse health impact:

• Arsenic 10?g/l
• Barium 10?g/l
• Boron 2400?g/l
• Chromium 50?g/l
• Fluoride 1500?g/l
• Selenium 40?g/l
• Uranium 30?g/l

For the potential occurrence in drinking water of artificial or synthetic pollutants generated by human activities, the following standards have been proposed:

• Cadmium 3?g/l
• Mercury 6?g/l For inorganic mercury

Organic species:

• Benzene 10?g/l
• Carbon tetrachloride 4?g/l
• 1,2-Dichlorobenzene 1000?g/l
• 1,4-Dichlorobenzene 300?g/l
• 1,2-Dichloroethane 30?g/l
• 1,2-Dichloroethene 50?g/l
• Dichloromethane 20?g/l
• Di(2-ethylhexyl)phthalate 8 ?g/l
• 1,4-Dioxane 50?g/l
• Edetic acid 600?g/l
• Ethylbenzene 300 ?g/l
• Hexachlorobutadiene 0.6 ?g/l
• Nitrilotriacetic acid 200?g/l
• Pentachlorophenol 9?g/l
• Styrene 20?g/l
• Tetrachloroethene 40?g/l
• Toluene 700?g/l
• Trichloroethene 20?g/l
• Xylenes 500?g/l
  

2. Soil pollution

As the number of people on earth increases so they need more food, more energy and more. space in which to build homes, schools, parks and so on. Each person regularly produces large amounts of solid waste which they throw away. These waste products include food, paper, garden waste, glass bottles, metal cans, cloth and plastics. Some of this waste is quickly broken down by bacteria (decomposers), but much of it, including plastic, metal and glass, remains unchanged since it cannot be broken down by bacteria. We call material that cannot be broken down by bacteria non-biodegradable. If we carelessly throw away such material then’ it pollutes the environment, often for a very long time. However, waste such as paper, wool, vegetables and food are soon broken down by bacteria. Because of this they are deseribed as biodegradable. People dispo se of large amounts of their waste by burning or burying it. In the past most trash was collected and then thrown onto open rubbish dumps. However, this kind of disposal caused problems, since the dumps looked ugly and smelled badly. Sometimes the trash in open dumps was burned causing air pollution.

If a lot of fertilizer is added to the soil, it may drain into lakes and rivers from the soil. Fertilizers contain nitrate and other nutrients which cause water pollution. Bacteria and algae grow rapidly in water and use up most of the oxygen. As a result, the fish and other organisms become ill and die. Some of the nitrate may get into peoples drinking water leading to cancers.

Pesticides are used on farms to kill insects, but they pollute the soil. Plants take in chemicals (pesticides) from the soil, animals and people then eat the plants and become ill.

Detergents get into the soil from homes and factories. Most of them get broken up quickly, but if a lot of detergent gets into the soil it may cause foaming and it may also poison plants and other living things in the soil You learned that living things in the soil make the soil rich by decaying dead bodies and helping life cycles. Without living things the soil becomes poor and unproductive.

Poisonous (toxic) wastes from factories are put into barrels burried the ground. Some liquid toxic wastes soak into the ground and poison the soil.

As more and more people liye on the earth we must build more homes, schools, roads, and factories and farms. Each time we build something we change the land. Whenever people build, plants are lost. In a city with larged paved areas, very little rain or melted snow soaks into the ground. Flooding and erosion often happen in and around cities. The loss of too many plants can raise the amount of carbondioxide in the air.

People can do things to change their environment and make it a more healthy and pleasant place to liye. Planning for the best use of the land can help the environment. Many cities have zoning regulations to control land use. These regulate the size and height of buildings and which areas are designated for homes and which for factories. Parks and community gardens are also planned to provide open spaces.

3. Pesticides

PESTICIDES IN OUR ECONOMY

INTRODUCTION       

        A pesticide is a material used to kill or reject a pest. Pesticides have disadvantages and advantages. They are able to restrain pests, but it can also kill other organisms as well. Not only do they affect animals but they can effect us, as humans.

        A pesticide is a biological, physical, or chemical agent used to kill plants or animals that are harmful to people. The name pesticide is generally applied only to chemical agents.

Examples of different pesticides are known as, herbicides nematicides and rodenticides.
        There has been concern regarding the effects of chemical pesticides on human and on the environment.

ADVANTAGES       

        The advantages of pesticides are to improve crop quality and supply and greatly improved Human health around the world.
1. Pesticides improve crop production and harvest productivity. Pesticides also prevent diseases found in fresh fruits and vegetables as well.

2. Chemical pesticides now go through thorough and expensive test before government registration and release.

3. Pesticides sprayed onto crops can be washed off. So it is very rare to get poisoned by vegetables you eat.

4. Poisonous and possible health effects have been verified.

 5. New types of pesticides makes the use of herbicides or fertilizers possible and there is no damage to the crops.
         Now many fruit and vegetable growers use fewer pesticides to protect their crop from pests, so it is better for the farmers health. With the use of pesticides more crops grow on our land. The more crops we grow on our land, the more we can gain from exporting our produce to other countries.

  DISADVANTAGES

        The disadvantages of using the pesticides are;
For instant,pesticides cause a number of pollution problems through spray drift on to surrounding areas direct contamination of users or the public and as residues on food.        

        "The World Health Organization" (WHO) estimated in 1999 that 20,000 people die annually worldwide from pesticides poisoning incident.However, many consumers are concerned about the effects of pesticide residues in foods, especially for infants, whose systems have weaker resistance levels to poisons than adults.    

        Another disadvantage is that pesticides can be cause cancer for anyone who are often exposed the pesticides. In 1986, the US issued a report that the chemical could also cause birth defects.

        Humans are often exposed to pesticides usually as a result of exposure, such as accidental inhalation, on the job. Concerns have been made for farm workers in other countries. The protective safeguards are not enough and their health is being threatened by the continued use of pesticides that are
known health hazards. That is why people that using or applying them pesticides should be very careful on handling the chemicals. Proper attire is required on handling the pesticides.

CONCLUSION

        In Conclusion there are many disadvantages and advantages to pesticide use. The main disadvantages to pesticides is that they are very hazardous to your health if used incorrectly.

        We know that many people have concerns about the uncertain effects of pesticides. However, we really need pesticides for the growth of our economy. We need fruits and vegetables to live and sometimes weeds, pests and other diseases make it harder for us to get proper nutrition. Now a days, there are hazardous chemicals in everything from shampoo to toothpaste. We cannot avoid the use of chemicals in everyday products. Yet, we can make ourselves aware of the use of pesticides and use them wisely.

4. Solid Waste Management

The reuse and recycling of solid wastes can also serve as a means for conservation of energy. In the light of this, let use see, what are the principles guiding the management of solid wastes. Recognizing that our resources are finite and continued pollution will be difficult to rectify in coming times, the management of solid wastes has become important.

Before disposal, a waste should be considered for the following possibilities:

• Reduction in raw materials and solid waste quantities
• Reuse of waste materials
• Materials recovery
• Energy recovery

i) Reduction in Raw Materials and solid Waste

Solid wastes are generated at the start of the process beginning with the mining of raw material. Thereafter, solid wastes are generated at every step in the process of conversion of goods into products. The products are then used by the consumer whence again wastes are generated. Clearly if a reduction in the usage of raw materials is to occur the quantity of waste must be curtailed. This can be achieved by

(a) Reducing the amount of materials used in the manufacture of a product,

(b) Increasing the life of the product, and

(c) Reducing the amount of materials used for packing the consumer goods.

ii) Reuse of Waste Materials

Reuse of waste materials now occurs most commonly in those situations where a product has utility in more than one application. For example, the paper bags used to bring home groceries are used to store household wastes prior to placing them in containers used for storage for collection. Soup and vegetable containers are used to store cooking medium, like ghee or oil.

Newspapers are used to start fires in fireplaces; they are also tightly rolled and used as logs for burning. While all the above reuses are important, their impact on generation of solid wastes is minimal. A much larger impact would occur if this habit is encouraged on a large-scale, in urban and town communities.

iii) Material Recovery and Recycling

A number of materials present in municipal and industrial waste are suitable for recovery and recycling about 10-15 percent of solid waste are recoverable. Most suitable candidates are the wastes generated by paper, cardboard, glass, ferrous metals, metals (mostly aluminum) and rubber. On the country, plastics, leather, textile and food wastes are unsuitable candidates for materials recovery. This is why; it is advisable to save on the number of polyethylene packets, when purchasing consumer goods.

Fly ash, which is a dust like by-product of the thermal powder plants, is produced in huge quantities. Over 22mt of fly ash from thermal power sector was available for utilization in 1985-86. It appears that the fly ash can be compressed into bricks as such or in combination with cement etc., that can be used for building houses.

iv) Energy Recovery

Alter segregation of wastes in the above-mentioned categories, the remainder is considered for the recovery of heat by burning (incineration). Because about 70 percent of the components that comprise solid waste are organic, the potential for recovery of heat energy is high. The energy content in the waste matter is converted to a form that can be used more easily. The remainder (ash) is also more compact and weighs less, occupying a smaller volume.

A wide variety of waste construction materials, municipal sewage and industrial by-products, forestry waste and urban waste (like rags, plastic bags, newspapers, etc.) are generated by modern human activities. Such wastes can be used for incineration to recover their heat energy. For instance, about 10 percent biomass produced in paddy fields forms rice grain, the remaining 90 percent is usually burnt but can be put to good use. If burnt in skillfully managed incinerators, paddy straw turns out to be far cheaper (about one third) than local as fuel for power generation. It has substantial energy value ranging from 3,200 to 3,500 kcal/kg. The availability of paddy straw is also good. In Punjab alone, bout 5 Mt paddy straw is available. In remote areas, for power generation through small and medium units, the bulk of power needs of the farm sector can be easily met by using paddy straw.

Conservation of Physical Resources

Man is integral part of the biosphere and therefore, is totally dependent on its recourses. His future and even his survival, depends upon the rational use and conservation of the resources available to him.

If the environment is to continue to sustain life, it must be protected from the consequences of our own actions. Breathable air, clean water, fertile soil, and innumerable life forms, are all important resources that are vital to our own survival. This is particularly important because physical resources are limited.