Environmental Science PresentationFaculty: ARKSectionCourse: ENV 107

Presented By :-

Shafat Ahmed Chowdhury Lubaba Mannan Margarate Adhikari Md. Tasbirul Alam AbirMarzia Akter

Water, In other word “Life”

Water Pollution Water covers 71% of the Earth's surface.

It is vital for all known forms of life. Water on Earth moves continually through the water cycle of evaporation and transpiration condensation, precipitation, and runoff, usually reaching the sea. Evaporation and transpiration contribute to the precipitation over land. Water used in the production of a good or service is known as virtual water.

Facts Of Water Pollution

• Fourteen billion pounds of garbage, which is mostly plastic, is dumped into the ocean every year.

• The Ganges River in India is one the most polluted rivers in the world with sewage, trash, food, and animal remains.

• About 700 million people globally drink contaminated water.

• Pollution is one of the biggest killers in the world, affecting over 100 million people.

• Lack of proper sanitation in water leads to diseases like cholera, malaria and diarrhea.

A Clear Vision

Types and Causes of Water Pollution

• Oil Pollution : There are about 15 million water crafts on navigable waters throughout the world. Their combined waste discharges are equivalent to a city with a population of 2,000,000. Thus oil pollution, an oxygen demanding waste, is of concern not only from sensational major spills from ships and offshore drilling rigs but also from small spills and cleaning operations. The death of birds from oil spills has attracted much attention. The Fort Mercer and Pendleton Collision in 1952 reduced the wintering population of eider ducks from 5,00,000 to 1,50,000. Some believe that the jackals penguin, which lives in South Africa, is endangered because floating oil from tankers rounding the Cape of Good Hope is killing hundreds of thousands of these birds each year.

Types and Causes of Water Pollution

•Toxic Water Pollutants and Their Effects : Two main categories of water pollutants have been identified from environmental health point of view. The first group comprises conventional water pollutants that come primarily from non-industrial sources and are highly bio-degradable e.g. faecal coliform bacteria, nutrients, nitrates and sediments. They cause cholera, typhoid fever and gestro-enteritis. Chlorination of water is the only remedy but we should not forget that chlorination may pose health hazards of its own.

Types and Causes of Water Pollution

• Pesticides: Pesticides are biologically active chemicals used for killing plants or animal pests. It is a general term embracing insecticides, herbicides, fungicides etc. (Table). Sometimes a collective term biocide is used to include all these categories. Pesticides have been used in one form or another for more than 2,000 years, but the use became widespread only in the last century. The primary problem with pesticides is that they are intentionally toxic and if they are toxic to undesirable organisms, they may also be toxic to desirable one including ourselves. The danger from pesticides was brought to public attention in 1962 with the publication of SILENT SPRINGS, a book by Rachel Carson. During the last two decades the use of pesticides has increased 12 times (Freed et al. 1977) and millions of kilograms are produced every year.

Leather Industries

Tanneries make the ground water unfit for drinking, and irrigation.Groundwater of several places has been affected by tanneries. A tannery waste can contaminate the groundwater in a radius of 8km.The effluent from vegetable tanning is coloured which makes the waterturbid. Turbidity reduces light penetration,thereby reducing the photosyntheticactivity of aquatic plants. Pathogenic micro-organisms such as,Bacillus anthraces may increase in these waters and may be threatening for human beings.

Effects Of Water Pollution

• Effects on Agriculture: Use of wastewater and polluted surface and groundwater, contaminate crops and transmit disease to consumers and farm workers. Depositions of deleterious chemicals in soil leading to loss of soil fertility.

• Effects on human health: Increased incidence of tumors, ulcers due to nitrate pollution; Increased incidence of skin disorders due to contact with pollutants; Increased incidence of constipation, diarrhea, and infections to intestine.

• Groundwater contamination from pesticides causes reproductive damage within wildlife in ecosystems.

• Oil spills in the water causes animal to die when they ingest it or encounter it.  Oil does not dissolve in water so it causes suffocation in fish and birds.

Point And Non-Point Sources• Point Sources: (1) factories, (2) sewage

treatment plants (which re-move some but not all pollutants), (3) active and abandoned underground mines , and (4) oil tankers.

• Nonpoint sources: (1) acid deposition and (2) runoff of chemicals into surface water from croplands, livestock feedlots, logged forests, urban streets, lawns, golf courses, and parking lots.

Solution of Water Pollution

•Education: Making people aware of the problem is the first step to solving it. Greater public awareness can make a positive difference.

•Laws: . Environmental laws can make it tougher for people to pollute, but to be really effective they have to operate across national and international borders.If the laws are maintained people will be aware of polluting the environment.

Thank You!