INTRODUCTION

Pollution, contamination of Earth’s environment with materials that interfere with human health, the quality of life, or the natural functioning of ecosystems (living organisms and their physical surroundings). Although some environmental pollution is a result of natural causes such as volcanic eruptions, most is caused by human activities.

Thermal Inversion Smog surrounds the Angel Monument in Mexico City, Mexico, during a thermal inversion. Air pollution increases dramatically when a mass of cold air is trapped below a mass of warmer air. The absence of air circulation prevents pollution near Earth’s surface from escaping.

There are two main categories of polluting materials, or pollutants. Biodegradable pollutants are materials, such as sewage, that rapidly decompose by natural processes. These pollutants become a problem when added to the environment faster than they can decompose (see Sewage Disposal). Nondegradable pollutants are materials that either do not decompose or decompose slowly in the natural environment. Once contamination occurs, it is difficult or impossible to remove these pollutants from the environment.

Nondegradable compounds such as dichlorodiphenyltrichloroethane (DDT), dioxins, polychlorinated biphenyls (PCBs), and radioactive materials can reach dangerous levels of accumulation as they are passed up the food chain into the bodies of progressively larger animals. For example, molecules of toxic compounds may collect on the surface of aquatic plants without doing much damage to the plants. A small fish that grazes on these plants accumulates a high concentration of the toxin. Larger fish or other carnivores that eat the small fish will accumulate even greater, and possibly life-threatening, concentrations of the compound. This process is known as bioaccumulation.

II IMPACTS OF POLLUTION

Because humans are at the top of the food chain, they are particularly vulnerable to the effects of nondegradable pollutants. This was clearly illustrated in the 1950s and 1960s when residents living near Minamata Bay, Japan, developed nervous disorders, tremors, and paralysis in a mysterious epidemic. More than 400 people died before authorities discovered that a local industry had released mercury into Minamata Bay. This highly toxic element accumulated in the bodies of local fish and eventually in the bodies of people who consumed the fish. More recently research has revealed that many chemical pollutants, such as DDT and PCBs, mimic sex hormones and interfere with the human body’s reproductive and developmental functions. These substances are known as endocrine disrupters.

Pollution also has a dramatic effect on natural resources. Ecosystems such as forests, wetlands, coral reefs, and rivers perform many important services for Earth’s environment. They enhance water and air quality, provide habitat for plants and animals, and provide food and medicines. Any or all of these ecosystem functions may be impaired or destroyed by pollution. Moreover, because of the complex relationships among the many types of organisms and ecosystems, environmental contamination may have far-reaching consequences that are not immediately obvious or that are difficult to predict. For instance, scientists can only speculate on some of the potential impacts of the depletion of the ozone layer, the protective layer in the atmosphere that shields Earth from the Sun’s harmful ultraviolet rays.

Another major effect of pollution is the tremendous cost of pollution cleanup and prevention. The global effort to control emissions of carbon dioxide, a gas produced from the combustion of fossil fuels such as coal or oil, or of other organic materials like wood, is one such example. The cost of maintaining annual national carbon dioxide emissions at 1990 levels is estimated to be 2 percent of the gross domestic product for developed countries. Expenditures to reduce pollution in the United States in 1993 totaled $109 billion: $105.4 billion on reduction, $1.9 billion on regulation, and $1.7 billion on research and development. Twenty-nine percent of the total cost went toward air pollution, 36 percent to water pollution, and 36 percent to solid waste management.

In addition to its effects on the economy, health, and natural resources, pollution has social implications. Research has shown that low-income populations and minorities do not receive the same protection from environmental contamination as do higher-income communities. Toxic waste incinerators, chemical plants, and solid waste dumps are often located in low-income communities because of a lack of organized, informed community involvement in municipal decision-making processes.

III TYPES OF POLLUTION

Pollution exists in many forms and affects many different aspects of Earth’s environment. Point-source pollution comes from specific, localized, and identifiable sources, such as sewage pipelines or industrial smokestacks. Nonpoint-source pollution comes from dispersed or uncontained sources, such as contaminated water runoff from urban areas or automobile emissions.

The effects of these pollutants may be immediate or delayed. Primary effects of pollution occur immediately after contamination occurs, such as the death of marine plants and wildlife after an oil spill at sea. Secondary effects may be delayed or may persist in the environment into the future, perhaps going unnoticed for many years. DDT, a nondegradable compound, seldom poisons birds immediately, but gradually accumulates in their bodies. Birds with high concentrations of this pesticide lay thin-shelled eggs that fail to hatch or produce deformed offspring. These secondary effects, publicized by Rachel Carson in her 1962 book, Silent Spring, threatened the survival of species such as the bald eagle and peregrine falcon, and aroused public concern over the hidden effects of nondegradable chemical compounds.

A Air Pollution

Brown Smog Over Phoenix, Arizona Smog is caused by industrial and automobile pollution. It is compounded by temperature inversions, which cause the air pollution to be kept in a particular area for extended periods. Continued exposure to smog can result in respiratory problems, eye irritation, and even death.

Human contamination of Earth’s atmosphere can take many forms and has existed since humans first began to use fire for agriculture, heating, and cooking. During the Industrial Revolution of the 18th and 19th centuries, however, air pollution became a major problem. As early as 1661 British author and founding member of the British Royal Society John Evelyn reported of London in his treatise Fumifugium, “… the weary Traveller, at many Miles distance, sooner smells, than sees the City to which he repairs. This is that pernicious Smoake which fullyes all her Glory, superinducing a sooty Crust or Furr upon all that it lights.…”

Urban air pollution is commonly known as smog. The dark London smog that Evelyn wrote of is generally a smoky mixture of carbon monoxide and organic compounds from incomplete combustion (burning) of fossil fuels such as coal, and sulfur dioxide from impurities in the fuels. As the smog ages and reacts with oxygen, organic and sulfuric acids condense as droplets, increasing the haze. Smog developed into a major health hazard by the 20th century. In 1948, 19 people died and thousands were sickened by smog in the small U.S. steel-mill town of Donora, Pennsylvania. In 1952, about 4,000 Londoners died of its effects.

A second type of smog, photochemical smog, began reducing air quality over large cities like Los Angeles in the 1930s. This smog is caused by combustion in car, truck, and airplane engines, which produce nitrogen oxides and release hydrocarbons from unburned fuels. Sunlight causes the nitrogen oxides and hydrocarbons to combine and turn oxygen into ozone, a chemical agent that attacks rubber, injures plants, and irritates lungs. The hydrocarbons are oxidized into materials that condense and form a visible, pungent haze.

Eventually most pollutants are washed out of the air by rain, snow, fog, or mist, but only after traveling large distances, sometimes across continents. As pollutants build up in the atmosphere, sulfur and nitrogen oxides are converted into acids that mix with rain. This acid rain falls in lakes and on forests, where it can lead to the death of fish and plants, and damage entire ecosystems. Eventually the contaminated lakes and forests may become lifeless. Regions that are downwind of heavily industrialized areas, such as Europe and the eastern United States and Canada, are the hardest hit by acid rain. Acid rain can also affect human health and man-made objects; it is slowly dissolving historic stone statues and building facades in London, Athens, and Rome.

One of the greatest challenges caused by air pollution is global warming, an increase in Earth’s temperature due to the buildup of certain atmospheric gases such as carbon dioxide. With the heavy use of fossil fuels in the 20th century, atmospheric concentrations of carbon dioxide have risen dramatically. Carbon dioxide and other gases, known as greenhouse gases, reduce the escape of heat from the planet without blocking radiation coming from the Sun. Because of this greenhouse effect, average global temperatures are expected to rise 1.4 to 5.8 Celsius degrees (2.5 to 10.4 Fahrenheit degrees) by the year 2100. Although this trend appears to be a small change, the increase would make the Earth warmer than it has been in the last 125,000 years, possibly changing climate patterns, affecting crop production, disrupting wildlife distributions, and raising the sea level.

Air pollution can also damage the upper atmospheric region known as the stratosphere. Excessive production of chlorine-containing compounds such as chlorofluorocarbons (CFCs) (compounds formerly used in refrigerators, air conditioners, and in the manufacture of polystyrene products) has depleted the stratospheric ozone layer, creating a hole above Antarctica that lasts for several weeks each year. As a result, exposure to the Sun’s harmful rays has damaged aquatic and terrestrial wildlife and threatens human health in high-latitude regions of the northern and southern hemispheres.

B Water Pollution

The demand for fresh water rises continuously as the world’s population grows. From 1940 to 1990 withdrawals of fresh water from rivers, lakes, reservoirs, and other sources increased fourfold. Of the water consumed in the United States in 1995, 39 percent was used for irrigation, 39 percent was used for electric power generation, and 12 percent was used for other utilities; industry and mining used 7 percent, and the rest was used for agricultural livestock and commercial purposes.

Sewage, industrial wastes, and agricultural chemicals such as fertilizers and pesticides are the main causes of water pollution. The U.S. Environmental Protection Agency (EPA) reports that about 37 percent of the country’s lakes and estuaries, and 36 percent of its rivers, are too polluted for basic uses such as fishing or swimming during all or part of the year. In developing nations, more than 95 percent of urban sewage is discharged untreated into rivers and bays, creating a major human health hazard.

Polluted River in the United Kingdom The pollution of rivers and streams with chemical contaminants has become one of the most critical environmental problems of the 20th century. Waterborne chemical pollution entering rivers and streams comes from two major sources: point pollution and nonpoint pollution. Point pollution involves those pollution sources from which distinct chemicals can be identified, such as factories, refineries or outfall pipes. Nonpoint pollution involves pollution from sources that cannot be precisely identified, such as runoff from agricultural or mining operations or seepage from septic tanks or sewage drain fields. It is estimated that each year 10 million people die worldwide from drinking contaminated water.

Water runoff, a nonpoint source of pollution, carries fertilizing chemicals such as phosphates and nitrates from agricultural fields and yards into lakes, streams, and rivers. These combine with the phosphates and nitrates from sewage to speed the growth of algae, a type of plantlike organism. The water body may then become choked with decaying algae, which severely depletes the oxygen supply. This process, called eutrophication, can cause the death of fish and other aquatic life. Agricultural runoff may be to blame for the growth of a toxic form of algae called Pfiesteria piscicida, which was responsible for killing large amounts of fish in bodies of water from the Delaware Bay to the Gulf of Mexico in the late 1990s. Runoff also carries toxic pesticides and urban and industrial wastes into lakes and streams.

Erosion, the wearing away of topsoil by wind and rain, also contributes to water pollution. Soil and silt (a fine sediment) washed from logged hillsides, plowed fields, or construction sites, can clog waterways and kill aquatic vegetation. Even small amounts of silt can eliminate desirable fish species. For example, when logging removes the protective plant cover from hillsides, rain may wash soil and silt into streams, covering the gravel beds that trout or salmon use for spawning.

The marine fisheries supported by ocean ecosystems are an essential source of protein, particularly for people in developing countries. Yet pollution in coastal bays, estuaries, and wetlands threatens fish stocks already depleted by overfishing. In 1989, 260,000 barrels of oil was spilled from the oil tanker Exxon Valdez into Alaska’s Prince William Sound, a pristine and rich fishing ground. In 1999 there were 8,539 reported spills in and around U.S. waters, involving 4.4 billion liters (1.2 billion gallons) of oil.

C Soil Pollution

Pest Control or Pollution? Pest control has become a difficult issue for farmers because of its potential environmental impact. Although the insecticide being sprayed on this potato field will eliminate a generation of Colorado potato beetles, it may also contaminate local food and water sources.

Soil is a mixture of mineral, plant, and animal materials that forms during a long process that may take thousands of years. It is necessary for most plant growth and is essential for all agricultural production. Soil pollution is a buildup of toxic chemical compounds, salts, pathogens (disease-causing organisms), or radioactive materials that can affect plant and animal life.

Unhealthy soil management methods have seriously degraded soil quality, caused soil pollution, and enhanced erosion. Treating the soil with chemical fertilizers, pesticides, and fungicides interferes with the natural processes occurring within the soil and destroys useful organisms such as bacteria, fungi, and other microorganisms. For instance, strawberry farmers in California fumigate the soil with methyl bromide to destroy organisms that may harm young strawberry plants. This process indiscriminately kills even beneficial microorganisms and leaves the soil sterile and dependent upon fertilizer to support plant growth. This results in heavy fertilizer use and increases polluted runoff into lakes and streams.

Improper irrigation practices in areas with poorly drained soil may result in salt deposits that inhibit plant growth and may lead to crop failure. In 2000 bc, the ancient Sumerian cities of the southern Tigris-Euphrates Valley in Mesopotamia depended on thriving agriculture. By 1500 bc, these cities had collapsed largely because of crop failure due to high soil salinity. The same soil pollution problem exists today in the Indus Valley in Pakistan, the Nile Valley in Egypt, and the Imperial Valley in California.

D Solid Waste

Components of Municipal Solid Waste A person living in an industrialized nation produces a great variety of solid waste, often a mix of potentially reusable or recyclable items (such as paper and yard waste) and largely nonrecyclable material (such as food waste and many types of plastic). Of the municipal solid waste (the waste collected from residences and businesses) produced in the United States in 2000, about two-fifths of the paper, metal, and yard waste was recycled, and about one-quarter of the glass was recycled.

Solid wastes are unwanted solid materials such as garbage, paper, plastics and other synthetic materials, metals, and wood. Billions of tons of solid waste are thrown out annually. The United States alone produces about 200 million metric tons of municipal solid waste each year (see Solid Waste Disposal). A typical American generates an average of 2 kg (4 lb) of solid waste each day. Cities in economically developed countries produce far more solid waste per capita than those in developing countries. Moreover, waste from developed countries typically contains a high percentage of synthetic materials that take longer to decompose than the primarily biodegradable waste materials of developing countries.

Overflowing Landfill An average city dweller may produce a ton of refuse in a year, a volume that rapidly overflows local dumps. Cities running out of space for landfill often turn to incinerating their waste or transporting it to other areas, although up to 90 percent of the material might have been recycled.

Areas where wastes are buried, called landfills, are the cheapest and most common disposal method for solid wastes worldwide. But landfills quickly become overfilled and may contaminate air, soil, and water. Incineration, or burning, of waste reduces the volume of solid waste but produces dense ashen wastes (some of which become airborne) that often contain dangerous concentrations of hazardous materials such as heavy metals and toxic compounds. Composting, using natural biological processes to speed the decomposition of organic wastes, is an effective strategy for dealing with organic garbage and produces a material that can be used as a natural fertilizer. Recycling, extracting and reusing certain waste materials, has become an important part of municipal solid waste strategies in developed countries. According to the EPA, more than one-fourth of the municipal solid waste produced in the United States is now recycled or composted. Recycling also plays a significant, informal role in solid waste management for many Asian countries, such as India, where organized waste-pickers comb streets and dumps for items such as plastics, which they use or resell.

Expanding recycling programs worldwide can help reduce solid waste pollution, but the key to solving severe solid waste problems lies in reducing the amount of waste generated. Waste prevention, or source reduction, such as altering the way products are designed or manufactured to make them easier to reuse, reduces the high costs associated with environmental pollution.

E Hazardous Waste

Toxic Waste in Love Canal Residents of the Love Canal area in Niagara Falls were forced to evacuate when hazardous wastes leaking from a former disposal site threatened their health and homes in the late 1970s. One of the most notorious cases of toxic waste leakage, the crisis received attention on both local and national levels. Investigation spurred by public outrage revealed that many waste disposal sites like Love Canal existed nationwide; New York alone had several hundred. Several states passed stricter regulations on industrial waste disposal and allocated billions of dollars for the cleanup of contaminated areas.

Hazardous wastes are solid, liquid, or gas wastes that may be deadly or harmful to people or the environment and tend to be persistent or nondegradable in nature. Such wastes include toxic chemicals and flammable or radioactive substances, including industrial wastes from chemical plants or nuclear reactors, agricultural wastes such as pesticides and fertilizers, medical wastes, and household hazardous wastes such as toxic paints and solvents.

About 400 million metric tons of hazardous wastes are generated each year. The United States alone produces about 250 million metric tons—70 percent from the chemical industry. The use, storage, transportation, and disposal of these substances pose serious environmental and health risks. Even brief exposure to some of these materials can cause cancer, birth defects, nervous system disorders, and death. Large-scale releases of hazardous materials may cause thousands of deaths and contaminate air, water, and soil for many years. The world’s worst nuclear reactor accident took place near Chernobyl’, Ukraine, in 1986 (see Chernobyl’ Accident). The accident killed at least 31 people, forced the evacuation and relocation of more than 200,000 more, and sent a plume of radioactive material into the atmosphere that contaminated areas as far away as Norway and the United Kingdom.

Until the Minamata Bay contamination was discovered in Japan in the 1960s and 1970s, most hazardous wastes were legally dumped in solid waste landfills, buried, or dumped into lakes, rivers, and oceans. Legal regulations now restrict how such materials may be used or disposed, but such laws are difficult to enforce and often contested by industry. It is not uncommon for industrial firms in developed countries to pay poorer countries to accept shipments of solid and hazardous wastes, a practice that has become known as the waste trade. Moreover, cleaning up the careless dumping of the mid-20th century is costing billions of dollars and progressing very slowly, if at all. The United States has an estimated 217,000 hazardous waste dumps that need immediate action. Cleaning them up could take more than 30 years and cost $187 billion.

Hazardous wastes of particular concern are the radioactive wastes from the nuclear power and weapons industries. To date there is no safe method for permanent disposal of old fuel elements from nuclear reactors. Most are kept in storage facilities at the original reactor sites where they were generated. With the end of the Cold War, nuclear warheads that are decommissioned, or no longer in use, also pose storage and disposal problems.

F Noise Pollution

Sound Intensities Sound intensities are measured in decibels (dB). For example, the intensity at the threshold of hearing is 0 dB, the intensity of whispering is typically about 10 dB, and the intensity of rustling leaves reaches almost 20 dB. Sound intensities are arranged on a logarithmic scale, which means that an increase of 10 dB corresponds to an increase in intensity by a factor of 10. Thus, rustling leaves are about 10 times louder than whispering.

Unwanted sound, or noise, such as that produced by airplanes, traffic, or industrial machinery, is considered a form of pollution. Noise pollution is at its worst in densely populated areas. It can cause hearing loss, stress, high blood pressure, sleep loss, distraction, and lost productivity.

Sounds are produced by objects that vibrate at a rate that the ear can detect. This rate is called frequency and is measured in hertz, or vibrations per second. Most humans can hear sounds between 20 and 20,000 hertz, while dogs can hear high-pitched sounds up to 50,000 hertz. While high-frequency sounds tend to be more hazardous and more annoying to hearing than low-frequency sounds, most noise pollution damage is related to the intensity of the sound, or the amount of energy it has. Measured in decibels, noise intensity can range from zero, the quietest sound the human ear can detect, to over 160 decibels. Conversation takes place at around 40 decibels, a subway train is about 80 decibels, and a rock concert is from 80 to 100 decibels. The intensity of a nearby jet taking off is about 110 decibels. The threshold for pain, tissue damage, and potential hearing loss in humans is 120 decibels. Long-lasting, high-intensity sounds are the most damaging to hearing and produce the most stress in humans.

Solutions to noise pollution include adding insulation and sound-proofing to doors, walls, and ceilings; using ear protection, particularly in industrial working areas; planting vegetation to absorb and screen out noise pollution; and zoning urban areas to maintain a separation between residential areas and zones of excessive noise.

India faces a turbulent water future. Unless water management practices are changed – and changed soon – India will face a severe water crisis within the next two decades and will have neither the cash to build new infrastructure nor the water needed by its growing economy and rising population. Water is one of the critical inputs for the sustenance of mankind. It is used both terrestrial and aquatic environment for various activities, balancing the ecological system of global environment. Water is the important natural source, which is abundant in nature and cover about 2/3ds of earth surface. However, only 1% of the water resource is available as fresh water (i.e., surface water-rivers, lakes, reams, and ground water) for human consumption and other activities. The major uses of water are for irrigation (30%), thermal power plants (50%), while other uses are domestic (7%) and industrial consumption (~12%) (A. K. De, 2002).The United Nation’s report on “Water for People, Water for Life” (the first ever UN system wide evaluation on global water resources-2003) has put India a poor 120th for water quality among 122 nations covered. Only Belgium and Morocco are ranked worse than India. The quality indicator value was based on quality and quantity of fresh water (especially ground water), waste water treatment facilities, legalities like application of pollution regulations, India’s quality indicator value stood at -3.1 while for based ranked country Finland it was 1.85. The UN evaluation also ranked India 133 in a list of 180 countries for its poor water availability (1880m3 per person per year). Kuwait was ranked the poorest on water availability. Against the National average target of 135 lpcd of water and 180 lpcd per capita in large cities, the per capita availability is low and ranges from 165 lpcd in a few larger town to about 50 lpcd in most smaller towns. The availability of water in urban slums is about 27 lpcd. Urbanisation has given rise to a number of environmental problems such as water supply, wastewater generation and its collection, treatment and disposal in urban areas. In most cases wastewater is let out untreated and it either percolates into the ground and in turn contaminates the groundwater or is discharged into the natural drainage system causing pollution in downstream areas. Sewage and not the industrial pollution accounts for more than 75 per cent of the surface water contamination in India. Due to negligence, groundwater is also increasingly getting contaminated. In India less than 50% of the urban population has access to sewage disposal system. Most of the existing collecting systems discharge directly to the receiving water without treatment. Garbage, domestic and otherwise, is directly dumped into water bodies or roadside, which can often be washed into streams and lakes. The municipalities disposes off their treated or partly treated or untreated wastewater into natural drains joining rivers or lakes or used on land for irrigation or fodder cultivation or into sea or combination of these. Toxic chemicals from sewage water transfer to plants and entire in the food chain and affect public health. Pathogens occurring in the sewage water directly affect the mammals causing severe diseases. About 60 per cent of urban deaths in India are due to lack of safe drinking water facilities. Further deaths due to water borne diseases are second only to malnutrition. It is estimated that around 80% of water consumed by a household is let of to the drains of sewers as wastewater. There is substantial scope for segregated use of the water for further use for gardening, industrial cooling, street cleaning, vehicular washing, fire fighting, irrigation, yard cleaning, fountains, recreational lakes, etc. Though methods are available to improve the quality of recycled water to potable grade, the lack of social acceptance and prohibitive costs may prevent the adoption of these techniques. The importance of reuse and recycling of treated sewage and industrial effluents has been realized on account of two distinct advantages: reduction of pollution in the receiving water bodies and reduction in the requirement of fresh water for various uses. Reuse of municipal wastewater after necessary treatment to meet industrial water requirement is being practiced in India.

Thus, wastewater can be considered as both a resource and a problem. Wastewater and its nutrient content can be used extensively for irrigation and other ecosystem services. Its reuse can deliver positive benefits to the farming community, society, and municipalities. However, wastewater reuse also exacts negative externality effects on humans and ecological systems, which need to be identified and assessed. Before one can endorse wastewater irrigation as a means of increasing water supply for agriculture, a thorough analysis must be undertaken from an economic perspective as well. In this regard the comprehensive costs and benefits of such wastewater reuse should also be evaluated. Moreover, the economic effects of wastewater irrigation need to be evaluated not only from the social, economic, and ecological standpoint, but also from the sustainable development perspective.

Wastewater Characteristics

Sources of Wastewater

In general, municipal wastewater is made up of domestic wastewater, industrial wastewater, storm water, and by groundwater seepage entering the municipal sewage network.

1. Domestic wastewater consists of effluent discharges from households, institutions, and commercial buildings.

2. Industrial wastewater is the effluent discharged by manufacturing units and food processing plants.

3. Unlike in some developed cities where the systems are separate, there, the municipal sewage network also serves as the storm water sewer. Due to defects in the sewerage system, there is groundwater seepage as well, adding to the volume of sewage to be disposed.

Composition of sewage water

• Organic matter

• Nutrients (Nitrogen, Phosphorus, Potassium)

• Inorganic matter (dissolved minerals)

• Toxic chemicals (heavy metal and pesticides)

• Pathogens

Table 1. Major Constituents of Typical Domestic Wastewater

Constituent Concentration (mg/l)

Strong Medium Weak

Total solids 1200 700 350

Dissolved solids (TDS) 850 500 250

Suspended solids 350 200 100

Nitrogen (as N) 85 40 20

Phosphorus (as P) 20 10 6

Chloride 100 50 30

Alkalinity (as CaCO3) 200 100 50

Grease 150 100 50

BOD5 300 200 100

Source: UN Department of Technical Cooperation for Development (1985)

Quality parameters of importance

Parameters of health significance

Organic chemicals usually exist in municipal wastewaters at very low concentrations and ingestion over prolonged periods would be necessary to produce detrimental effects on human health. This is not likely to occur with agricultural/aquacultural use of wastewater, unless cross-connections with potable supplies occur or agricultural workers are not properly instructed, and can normally be ignored. The principal health hazards associated with the chemical constituents of wastewaters, therefore, arise from the contamination of crops or groundwaters. Hillman (1988) has drawn attention to the particular concern attached to the cumulative poisons, principally heavy metals, and carcinogens, mainly organic chemicals. World Health Organization guidelines for drinking water quality (WHO 1984) include limit values for the organic and toxic substances given in the table – 3 based on acceptable daily intakes (ADI). These can be adopted directly for groundwater protection purposes but, in view of the possible accumulation of certain toxic elements in plants (for example, cadmium and selenium) the intake of toxic materials through eating the crops irrigated with contaminated wastewater must be carefully assessed.

Table 2. Pollutants and contaminants in wastewater and their potential impacts

Pollutants/

Contaminants Parameters Impacts

Hydrogen ion concentration pH 1. Possible adverse impact on plant growth due to acidity /alkalinity.

2. Impact sometimes beneficial to flora and fauna.

Suspended solids Volatile compounds, settable, suspended and colloidal impurities 1. Development of sludge deposit.

Dissolved inorganic substances TDS, EC, Na, Ca, Mg, Cl and B 1. Cause salinity and associated adverse impacts

2. Phytotoxicity

3. Affect permeability and soil structure

Plant food nutrients N, P, K etc.

1. Excess N causes nitrogen injury, excessive vegetative growth, delayed growth season and maturity, causing economic loss of farmers.

2. Excessive of N and P cause excessive growth of undesirable aquatic life (eutropication)

3. Nitrogen leaching causes ground water pollution with adverse health and environmental impacts.

Heavy metals Fe, Mn, Cu, Cd, Cr, Pb, Ni, Zn, Ag, Hg etc, 1. Accumulate in aquatic organisms

2. Accumulate in sewage water irrigates soils and transfer to the plants and entire in the food chain and affect public health.

3. Toxic to plants and animals.

4. May make sewage water unsuitable for irrigation.

Pesticide residues Both parent molecules and metabolites 1. Ground and surface water contamination

2. Toxicity to mammals and aquatic organisms

3. residual organic compounds

4. Green-house effect.

Biodegradable organics BOD,COD 1. Depletion of D.O. in surface water.

2. Development of septic conditions.

3. Unsuitable habitat and Environment.

4. Can inhibit pond-breeding amphibians.

5. Fish death.

6. Humus build up

Source: Asano et.al. (1985)

Table 3. Organic and inorganic constituents of drinking water of

health significance

Organic Organic Inorganic

Aldrin and dieldrin 1,1 Dichlorethylene Arsenic

Benzene Heptachlor and heptachlor epoxide Cadmium

Benzo-a-pyrene Hexachlorobenzene Chromium

Carbon tetrachloride Lindane Cyanide

Chlordane Methoxychlor Fluoride

Chloroform Pentachlorophenol Lead

2,4 D Tetrachlorethylene Mercury

DDT 2, 4, 6 Trichloroethylene Nitrate

1,2 Dichloroethane Trichlorophenol Selenium

Source: WHO (1984)

Sewage water contains pathogenic microorganisms like bacteria, viruses, fungi, algal etc., having the potential risks to causes diseases can causes immense harm to public health. The water borne diseases are typhoid, paratyphoid fevers, dysentery and cholera, polio and infectious hepatitis. The responsible organisms occur in the faces or urine or infected people. Where raw untreated sewage water is used to irrigate crops helminthic disease caused by Ascaris, and Trichuris spp. as occurred in West Germany. Melbourne, Australia and from Denmark (reported by Shuval et al. 1985) that cattle grazing on fields freshly irrigated with raw wastewater, or drinking from raw wastewater canals or ponds, can become heavily infected with the disease (cysticerosis).

In India sewage farm workers exposed to raw wastewater in areas where Ancylostoma (hookworm) and Ascaris (nematode) infections are endemic have significantly excess levels of infection with these two parasites compared with other agricultural workers in similar occupations.

From the health point of view important microbiological parameter are coliform , fecal coliform, fecal streptococci and clostridium perfringens. Finally, in respect of the health impact of use of wastewater in agriculture, Shuval et al. (1986) rank pathogenic agents in the order of priority shown in Table 4. They pointed out that negative health effects were only detected in association with the use of raw or poorly-settled wastewater, while inconclusive evidence suggested that appropriate wastewater treatment could provide a high level of health protection. high level of health protection.

Table 4. Relative health impact of pathogenic agents

High Risk

Helminths

(Ancylostoma, Ascaris, Trichuris and Taenia)

Medium Risk

Enteric Bacteria

(Cholera vibrio, Salmonella typhosa, Shigella etc.

Low Risk

Enteric viruses

(Shuval et al. 1986)

Indicator organisms

A) Coliforms and Faecal Coliforms. The Coliform group of bacteria comprises mainly species of the genera Citrobacter, Enterobacter, Escherichia and Klebsiella and includes Faecal Coliforms, of which Escherichia coli is the predominant species. They are not itself harmful but presesnce of coliform groups of bacteria indicate t he presence of pathogenic bacte4ria and fecal coliforms indicate fecal contamination and presence of enteric pathogens in surrounding water. Several coliforms are able to grow out side of the intestines , specially in hot climates. Hence their enumeration is unsuitable as a parameter. The fecal coliforms can grow at 44 degree C, so E.coli, is most s satisfactory indicator parameter in sewage water use.

B) Faecal Streptococci. Faecal Streptococci as an indicator in tropical conditions and especially to compare survival with that of Salmonellae.

Clostridium perfringens. This bacterium is an exclusively faecal spore-forming anaerobe normally used to detect intermittent or previous pollution of water, due to the prolonged survival of its spores. In sewage water studies it is useful as it may have survival characteristics similar to those of viruses or even helminth eggs.

Parameters of agricultural significance

Sewage water contains soluble salts that may accumulate in the root zone with possible harmful effect on soil health and crop yield. The quality of irrigation water is of particular importance in arid zones where extremes of temperature and low relative humidity result in high rates of evaporation, with consequent deposition of salt which tends to accumulate in the soil profile. The physical and mechanical properties of the soil, such as dispersion of particles, stability of aggregates, soil structure and permeability, are very sensitive to the type of exchangeable ions present in irrigation water. Thus, when effluent use is being planned, several factors related to soil properties must be taken into consideration.

Another aspect of agricultural concern is the effect of dissolved solids (TDS) in the irrigation water on the growth of plants. Dissolved salts increase the osmotic potential of soil water and an increase in osmotic pressure of the soil solution increases the amount of energy which plants must expend to take up water from the soil. As a result, respiration is increased and the growth and yield of most plants decline progressively as osmotic pressure increases. Important Agricultural Water Quality parameters include a number of specific properties of water that are relevant in relation to the yield and quality crops, maintenance of soil productivity and protection of the environment. These parameters mainly consist of certain physical and chemical characteristics of the water. The primary wastewater quality parameters of importance from an agricultural viewpoint are:

Table 5. Guidelines for interpretation of water quality for irrigation

Potential irrigation problem Units Degree of restriction on use

None Slight to moderate Severe

Salinity

EC dS/m 3.0

TDS mg/l 2000

Specific ion toxicity

Sodium (Na)

Surface irrigation SAR 9

Chloride (Cl)

Surface irrigation me/I 10

Boron (B) mg/l 3.0

Miscellaneous effects

Nitrogen (NO3-N) mg/l 30

Bicarbonate (HCO3) me/I 8.5

pH Normal range 6.5-8.0

Source: FAO (1985)

A. pH

pH is an indicator of the acidity or basicity of water but is seldom a problem by itself. The normal pH range for irrigation water is from 6.5 to 8.4; pH values outside this range are a good warning that the water is abnormal in quality. Normally, pH is a routine measurement in irrigation water quality assessment.

B. Electrical Conductivity

Electrical conductivity is widely used to indicate the total ionized constituents of water. It is directly related to the sum of the cations (or anions). It should be noted that the electrical conductivity of solutions increases approximately 2 percent per °C increase in temperature. The symbol ECw, is used to represent the electrical conductivity of irrigation water and the symbol ECe is used to designate the electrical conductivity of the soil saturation extract. The unit of electrical conductivity is deciSiemen per metre (dS/m).

C. Total Salt Concentration

Total salt concentration (for all practical purposes, the total dissolved solids) is one of the most important agricultural water quality parameters. This is because the salinity of the soil water is related to, and often determined by, the salinity of the irrigation water. Accordingly, plant growth, crop yield and quality of produce are affected by the total dissolved salts in the irrigation water. Equally, the rate of accumulation of salts in the soil, or soil salinization, is also directly affected by the salinity of the irrigation water. Total salt concentration is expressed in milligrams per litre (mg/l) or parts per million (ppm).

D. Sodium Adsorption Ratio

Sodium is an unique cation because of its effect on soil. When present in the soil in exchangeable form, it causes adverse physico-chemical changes in the soil, particularly to soil structure. It has the ability to disperse soil, when present above a certain threshold value, relative to the concentration of total dissolved salts. Dispersion of soils results in reduced infiltration rates of water and air into the soil. When dried, dispersed soil forms crusts which are hard to till and interfere with germination and seedling emergence. Irrigation water could be a source of excess sodium in the soil solution and hence it should be evaluated for this hazard. The most reliable index of the sodium hazard of irrigation water is the sodium adsorption ration, SAR. The sodium adsorption ratio is defined by the formula and the ionic concentrations are expressed in me/l.

E. Toxic Ions

Irrigation water that contains certain ions at concentrations above threshold values can cause plant toxicity problems. The most common phytotoxic ions that may be present in municipal sewage and treated effluents in concentrations such as to cause toxicity are: boron (B), chloride (Cl) and sodium (Na). Hence, the concentration of these ions will have to be determined to assess the suitability of waste-water quality for use in agriculture.

F. Trace Elements and Heavy Metals

A number of elements are normally present in relatively low concentrations, usually less than a few mg/l, in conventional irrigation waters and are called trace elements. They are not normally included in routine analysis of regular irrigation water, but attention should be paid to them when using sewage effluents, particularly if contamination with industrial wastewater discharges is suspected. These include Aluminium (Al), Beryllium (Be), Cobalt (Co), Fluoride (F), Iron (Fe), Lithium (Li), Manganese (Mn), Molybdenum (Mo), Selenium (Se), Tin (Sn), Titanium (Ti), Tungsten (W) and Vanadium (V). Heavy metals are a special group of trace elements which have been shown to create definite health hazards when taken up by plants. Under this group are included, Arsenic (As), Cadmium (Cd), Chromium (Cr), Copper (Cu), Lead (Pb), Mercury (Hg) and Zinc (Zn). These are called heavy metals because in their metallic form, their densities are greater than 4g/cc. The threshold levels of trace elements for crop production are given in Table – 6.

Table 6. Threshold levels of trace elements for crop production

Element Recommended maximum concentration (mg/l) Remarks

Al (aluminium) 5.0 Can cause non-productivity in acid soils (pH 7.0 will precipitate the ion and eliminate any toxicity.

As (arsenic) 0.10 Toxicity to plants varies widely, ranging from 12 mg/l for Sudan grass to less than 0.05 mg/l for rice.

Cd (cadmium) 0.01 Toxic to beans, beets and turnips at concentrations as low as 0.1 mg/l in nutrient solutions. Conservative limits recommended due to its potential for accumulation in plants and soils to concentrations that may be harmful to humans.

Co (cobalt) 0.05 Toxic to tomato plants at 0.1 mg/l in nutrient solution. Tends to be inactivated by neutral and alkaline soils.

Cr (chromium) 0.10 Not generally recognized as an essential growth element. Conservative limits recommended due to lack of knowledge on its toxicity to plants.

Cu (copper) 0.20 Toxic to a number of plants at 0.1 to 1.0 mg/l in nutrient solutions.

F (fluoride) 1.0 Inactivated by neutral and alkaline soils.

Fe (iron) 5.0 Not toxic to plants in aerated soils, but can contribute to soil acidification and loss of availability of essential phosphorus and molybdenum. Overhead sprinkling may result in unsightly deposits on plants, equipment and buildings.

Li (lithium) 2.5 Tolerated by most crops up to 5 mg/l; mobile in soil. Toxic to citrus at low concentrations ( 6.0 and in fine textured or organic soils.

Source: National Academy of Sciences (1972) and Pratt (1972).

Potential impacts of wastewater in environment

This section provides the potential impacts of wastewater use in various substrates

1. Public Health & Other living organism

2. Crops

3. Social Resources

4. Ground Water resources

5. Property values

6. Ecological impacts

7. Social Impacts

1. Public health& other living organisms: Use of untreated sewage water pose a high risk to human health& other living organisms in all groups as it contain pathogenic microorganisms which have the potential to cause diseases.

2. Crops

Generally speaking, wastewater (treated and untreated) is extensively used in agriculture because it is a rich source of nutrients and provides all the moisture necessary for crop growth. Most crops give higher than potential yields with wastewater irrigation; reduce the need for chemical fertilizers, resulting in net cost savings to farmers.

3. Soil Resources

Impact from wastewater on agricultural soil, is mainly due to the presence of high nutrient contents (Nitrogen and Phosphorus), high total dissolved solids and other constituents such as heavy metals, which are added to the soil over time. Wastewater can also contain salts that may accumulate in the root zone with possible harmful impacts on soil health and crop yields. The leaching of these salts below the root zone may cause soil and groundwater pollution (Bond 1999). Prolonged use of saline and sodium rich wastewater is a potential hazard for soil as it may erode the soil structure and effect productivity. This may result in the land use becoming non-sustainable in the long run. Wastewater induced salinity may reduce crop productivity (Kijne et al. 1998). The net effect on growth may be a reduction in crop yields and potential loss of income to farmers. Wastewater irrigation may lead to transport and bio-accumulate heavy metals to soils, affecting soil flora and fauna. e.g., Cd and Cu, may be redistributed by soil fauna such as earthworms (Kruse and Barrett 1985). In general, heavy metal accumulation and translocation is more a concern in sewage sludge application than wastewater irrigation, because sludge formed during the treatment process consists of concentrations of most heavy metals. The impact of wastewater irrigation on soil may depend on a number of factors such as soil properties, plant characteristics and sources of wastewater.

4. Groundwater Resources

Wastewater application has the potential to affect the quality of groundwater resources in the long run through excess nutrients and salts found in wastewater leaching below the plant root zone. For instance the quality of groundwater would determine the magnitude of the impact from leaching of nitrates. Groundwater constitutes a major source of potable water for many developing country communities. Hence the potential of groundwater contamination needs to be evaluated before embarking on a major wastewater irrigation program. In addition to the accretion of salts and nitrates, under certain conditions, wastewater irrigation has the potential to translocate pathogenic bacteria and viruses to groundwater (NRC report 1996).

Farid et al. (1993), reported that the long-term use of wastewater for crop irrigation has interestingly led to an improvement in the salinity of the groundwater. This was offset by evidence of coliform contamination of groundwater which was also observed in Mexico (Downs et al. 1999, Gallegos et al. 1999). A companion study (Rashed et al. 1995), reveals that in the wastewater irrigated Gabar el Asfar region, concentrations of chloride, sulfate, TDS, and dissolved oxygen in groundwater is much higher than average concentrations in sewage effluents. The leaching and drainage of wastewater, applied for crop irrigation, to groundwater aquifer may serve as a source of groundwater recharge. In some regions, 50-70 percent of irrigation water may percolate to groundwater aquifer (Rashed et al. 1995).

5. Ecological Impacts

When drainage water from wastewater irrigation schemes drains particularly into small confined lakes and water bodies and surface water, and if phosphates in the orthophosphate form are present, the remains of nutrients may cause eutrophication (Smith et al. 1999). For example, overloading of organic material resulting in decreases in dissolved oxygen may lead to changes in the composition of aquatic life, such as fish deaths and reduced fishery. The eutrophication potential of wastewater irrigation can be assessed using biological indices or biomarkers, which in turn can be quantified in monetary units using appropriate economic valuation techniques.

6. Social Impacts

In the context of this analysis social impacts are the concerns/doubts expressed by the public about wastewater irrigation. These concerns can be classified as follows:

General concerns such as nuisance, poor environmental quality, poor hygiene, odor, noise, higher probability of accidents, etc.

Social concerns such as food safety, health and welfare, impaired quality of life, loss of property values, and sustainability of land use.

Natural resource concerns such as pollution of vital water resources, loss of fish, wildlife, exotic species, etc.

7. Economics of Wastewater Irrigation

To date, in relation to wastewater irrigation, economic analyses have been conducted with specific perspectives in mind viz that of a municipality optimizing treatment costs, or that of farmers or a regional entity maximizing income, or that of evaluating environmental impacts.

The researchers evaluated the effect of crop selection on cost and revenue streams and system efficiency by selecting three cropping patterns viz. reed canary grass, alfalfa, corn and forest plantations. Wastewater can also be used for producing rapidly growing pulpwood, such as eucalyptus, on public lands, along canal banks, roads and greenbelts etc. These plants can be harvested every 8 to 10 years to generate revenue, along with the added advantage of working as natural air conditioners and greenhouse gas sinks, for ameliorating the highly polluted urban environments.The main benefits from wastewater irrigation are effective water and nutrient recycling, higher crop yields, a diversified cropping pattern, and disposal cost savings. Segarra et al. (1996), suggested that alfalfa, wheat-corn, wheat-grain sorghum, and cotton are optimal crop combinations to maximize net revenue. It, therefore, implies that municipalities can benefit from cooperative arrangements with neighboring farmers for wastewater irrigation. A recent IWMI study (Scott et al. 2000), evaluated the economic value and risks associated with long-term use of urban wastewater for crop irrigation in Guanajuato, Mexico. The study was conducted to predict changes in water quality under various wastewater management scenarios. The study used an opportunity cost or replacement value approach to estimate dollar values for water and nutrient contents of wastewater. The findings suggest that wastewater is a valuable resource for the community and wastewater reuse for irrigation is an economical alternative to expensive treatment. However, the study recognizes that there could be negative health and environmental impacts of wastewater use, and that these impacts should be evaluated.

Waste water treatment procedure adopted in India

 Activated sludge process

 Trickling filter

 Oxidation pond and Waste stabilization pond

Status of sewage and sewage treatment in India

The total wastewater generated by 23 metropolitan cities is 9,275 mld. Out of 9,275

mld of total wastewater generated, only 31% (2,923 mld) is treated before letting out

and the rest i.e. 6,352 mld is disposed off untreated. Three cities have only primary treatment facilities and thirteen have primary and secondary treatment facilities. In India less than 50% of the urban population has access to sewage disposal system. Most of the existing collecting systems discharge directly to the receiving water without treatment. Garbage, domestic and otherwise, is directly dumped into water bodies or roadside, which can often be washed into streams and lakes. This vulnerable environment requires special attention and the solution of such complex and interdisciplinary problems call for an integrated water resources management approach.

The municipalities (governing bodies of metropolitan cities) disposes off their treated or partly treated or untreated wastewater into natural drains joining rivers or lakes or used on land for irrigation or fodder cultivation or into sea or combination of these. In four cities, it is disposed indirectly into the rivers/lakes, while in two cities it is disposed into sea/creek and the rest partly used for agriculture and partly disposed into rivers. It is found that in 12 metropolitan cities there is some level of organized sewage farming under the control of government or local body (CPCB, August 1997).

In India, till now very little emphasis has been laid on research on hydrology of urban

areas. Taking into account that the trends of urban population concentration increase will continue in the future, a programme for encompassing all hydrological, ecological and socio-economic aspects of future urban planning and management needs to be taken up in right earnest. This would require improvement in the management of existing urban drainage systems, disseminate knowledge of integrated urban water management, identify the impact of urbanization on surface and ground water quality through point and nonpoint sources, to study impact of storm water (wastewater discharges) on ecosystem health of receiving water courses and to establish experimental urban catchments.

Water quality guidelines

From effect of sewage water several guidelines are produced to minimize the potential risk. WHO guidelines is used on the safe use of water for agriculture and aquaculture. The rationale behind the WHO guidelines was to develop criteria that would present the transmission of communicable diseases caused by microorganisms while optimizing resource conservation and recycling. Recent evidence suggest that these guidelines are used only to crop consumers but not necessarily farmers, farm workers and their families, thereby meeting this guidelines debatable. In order to evaluate the financial feasibility of WHO and USEP a microbial health guidelines, Shuval et al. (1997), developed a risk assessment approach to conduct a comparative risk analysis. Most European countries, with the exception of Germany and France, have not established any guidelines for the use of wastewater for irrigation. The EU guidelines, when formulated, propose to cover both agronomic aspects, of soil and groundwater protection, yield maximization, and the sanitary aspects, relating to public health protection.

Conclusion

Rapid urbanization places immense pressure on the world’s fragile and dwindling fresh water resources and over-burdened sanitation systems, leading to environmental degradation. Thus, it is quiet justified and seems logistic to say that:

1. Wastewater (raw, diluted or treated) is a resource of increasing global importance.

2. Without proper management sewage water use poses high risks to human health and cause environmental degradation Thus scientists around the world refocus on conserving water, recycling of water and treatment of sewage water through sewage treatment plant.

3. With proper management, wastewater use contributes significantly to sustaining livelihoods, food security and the quality of the environment.

Parameters for Water Quality Characterization & Standards

(Domestic Water Supply)

parameters USPH Standard ISI Standard

Color, odour, state Colorless, odorless, tasteless -

Inorganic Chemicals

pH 6.0-8.5 6.0-9.0

conductance 300mmho/cm -

D.O 4.0-6.0 ppm 3.0

TDS 500 -

Suspended Solid 5.0 -

SO42- 250 100

Cl- 250 600

F- 1.5 3.0

PO43- 0.1 -

S- 0.1mg/L -

Ammonia 0.5 -

B 1.0 -

Ca2+ 100 -

Mg2+ 30 -

As 0.05 0.2

Cd 0.01 -

Cr 0.05 0.05

Cu 1.0 -

Fe Less than 0.3 -

Pb Less than 0.05 0.01

Mn Less than 0.05 -

Hg 0.001 -

Ag 0.05 -

U 5.0 -

Zn 5.5 -

Organics

COD 4.0 -

Phenols 0.001 0.005

Pesticides(total) 0.005 -

Polycyclic aromatic hydrocarbons(PAH) 0.002ppm -

Surfactants 200 -

Biological parameters

Coliform cells/1000mL 100 Less than5000

Total bacteria count/100mL 1×106

4. Sewage treatment cost studies shows that marginal cost are very high at higher levels of treatment at higher levels of treatment. However, these costs become justifiable in view of the value of the degree of water scarcity and public concern. Cost-effective and appropriate treatment suited to the end use of wastewater, supplemented by guidelines and their application.

5. Proposed guidelines should link heath, agriculture and environmental quality, which are implemented in a stepwise approach.

6. Reduction of toxic contaminants in sewage water is essential by improved management practices.

7. Where sewage water is insufficiently treated due to lack of treatment facilities there some steps should be taken, which are

(a) Development and application of guidelines for untreated wastewater use that will safe livelihoods, public health and the environment.

(b) Application of appropriate irrigation, agricultural, post-harvest, and public health practices that limit risks to farming communities, vendors, and consumers.

(c) Education and awareness programs for all stakeholders, including the public at large, to disseminate these measures.

8. Therefore, we strongly urge policy-makers and authorities in the fields of water, agriculture, aquaculture, health, environment and urban planning, as well as donors and the private sector to.

“ Safeguard and strengthen livelihoods and food security, mitigate health and environmental risks and conserve water resources by confronting the realities of wastewater use in agriculture through the adoption of appropriate policies and the commitment of financial resources for policy implementation”.

———

*Correspondence to: Md. Wasim Aktar, e-mail id : wasim04101981@yahoo.co.in

Tel. No. +91-9474126188, Fax no. +91-33-2582 8407

Cruise ships are a major and growing source of ocean pollution. Cruise ships produce and dump millions of gallons of inadequately treated sewage and wastewater into the sea daily. 

Take a look at what cruise ships generate everyday:

1) Blackwater (Human waste)
Blackwater is sewage, wastewater from toilets and medical facilities, which can contain harmful bacteria, pathogens, viruses, intestinal parasites, and harmful nutrients. Discharges of untreated or inadequately treated sewage can cause bacterial and viral contamination of fisheries and shellfish beds, producing risks to public health. 

2) Graywater
Graywater is wastewater generated by laundries, showers, sinks and dishwashers. It contains detergents, cleaners, oil and grease, metals, pesticides, and medical, dental and other forms of toxic waste. Waste that should be segregated and disposed at land-based facilities is often pumped into graywater. 

3) Garbage and solid waste
This trash of ocean pollution includes glass, plastics, bottles, aluminium, steel, cans, paper, cardboard and food wastes. Approximately 75 to 80 percent is incinerated at sea and then the ash is dumped into the ocean. It can be either non-hazardous or hazardous in nature.

4) Hazardous waste (toxic waste)
Cruise ships produce hazardous wastes (toxic) from a number of on-board activities and processes, including silver, mercury, lead and cadmium through dry cleaning, photo processing photographic processing, print shops, painting activities, equipment cleaning and other sources.

5) Oily bilge water
Residual oil from routine engine maintenance mixes with bilge water and collects at the bottom of the ship. Ocean pollution like oil, gasoline, and by-products from the biological breakdown of petroleum products can harm fish and wildlife and pose threats to human health if ingested.

6) Ballast water, 1,000 metric tons per release.
Ballast water is often taken on in one region and discharged in another.Cruise ships take in millions gallons of ballast water to stabilize and trim the vessel, discharge back into the ocean as needed to maintain and to ensure safe operating conditions. 

> Ballast water is often contains non-native, nuisance, exotic species that can cause extensive ecological and economic damage to aquatic ecosystems. 

> Non-native species are the number two cause of biodiversity loss worldwide.

7) Air pollution
Air pollution generated by cruise ship diesel engines that burn high sulfur content fuel, producing sulfur dioxide, nitrogen oxide and particulate, in addition to carbon monoxide, carbon dioxide, and hydrocarbons.

> Diesel exhaust has been classified by U.S. Environmental Protection Agency (EPA) as a likely human carcinogen, i.e. a substance, radionuclide or radiation that is an agent directly involved in the promotion of cancer or in the increase of its propagation.

The diverse collection of wastes described above, including toxic waste,human waste and chemical pollution contaminate the sea water, damage corals, deplete the oxygen supply in the ocean, and harm both marine and human life.

Source Article: Visit http://www.smart-guide-to-world-cruise-ship.com/ocean-pollution.html for your good research purpose to learn more detail about ocean pollution done by cruise ship!

As the world’s most northerly tropical sea, it is very popular with European divers and offers hundreds of top diving spots. Not only is it extremely diverse in marine life, but with an average water temperature of around 26C, good visibility and a small tidal range it is also considered a safe place to dive. Though the Red Sea laps the shores of several North African and Middle Eastern countries, including Sudan, Eritrea, Somalia, Saudi Arabia and Yemen, it is Egypt that is best known as the host of diving holidays.

For experienced divers, the Red Sea’s many wreck sites offer a fascinating glimpse of marine history and also how nature can take man-made materials and use them as a habitat. Examples of this includes the ‘Ghiannis D’, a Greek boat that sunk in 1983 after colliding with another wreck. Divers can swim through the deserted hull and see large moray eels, shoals of batfish, and butterfly fish.

‘Thistlegorm’, a British ship that was sunk by bombers in 1941 is rated as one of the top ten best diving sites in the world. Much of the huge vessel’s cargo is very well persevered and can still be seen, such as motorbikes, rifles and even train carriages!

Egypt is well equipped for hosting diving holidays, and divers of all levels – from complete beginners to experienced scuba masters – are well catered for. Live-aboard diving holidays are one of the best ways of maximising your underwater time and offer comfortable accommodation, with double or twin cabins, large air conditioned rooms with en-suite bathrooms available. Most also offer plenty of indoor and on-deck seating and a bar where guests can purchase soft drinks as well as beer and wine. Experienced crew members provide catering as well as guidance to the best diving sites in the area.

With such as wealth of diving opportunities, it’s little wonder that the Red Sea, and Egypt in particular continues to be one of the most popular diving spots in the world.

If this is happening in pristine Canada, how is your national back yard? We all need to be aware of toxins in our own home, under the sink, in the basement or garage. If is has been simmering away for some time, take it away. Recycling depots are now common, but we learn all too common is that those toxic expensive bits are pulled out by hand in Asia, and then the plastic burnt off to salvage the copper wire, that smoke and ash drifting across the Pacific onto Americas forests and into Americas lungs.

By the billions, as you can imagine, and increasing daily. Like the world temperature, merrily skipping upward. Is any one able to measure those skipping upward numbers by the time and let us know when the sea will be up to our ankles? Our knees? When should we open a gondola franchise?

There is hope. And even while additional mineral and oil sands projects go into higher gear, we need to ensure that we become world leaders, not followers, in helping create a greener world. That U.N. World Clock is ticking, showing how the earth average temperature is now 14.1 something to the tenth power.

And it is those farthest numbers to the right that we should be paying more attention: they are merrily skipping upwards as you watch. No up or down movement at any time you watch. Especially, we in the west need to clean up our act, and then help the developers such as China and India with our technology: common reason must prevail.

And if babies are being stillborn in healthy Canada due to pollution, imagine how bad and worse it is getting in so many third world nations, where bribes to officials still allow ecological nightmares.

We all breath the same air and share the ocean wastes. We need to grow up and accept that there is not a potty section in the pool any more. Let us be aware that we need to personally do all we can to green up, but also to encourage our governments, at every level, to get off the pot. Or out of the pool. Or at least clean up after.

The omega-3 fatty acids that are  found in fish oil are very beneficial for heart health, brain health, skin and the joints. The source of deep sea fish oil is very important because a majority of the seas and oceans have been contaminated by unabated industrial pollution over many decades. The fish commonly used for fish oils are salmon, halibut, shark, sardines and cod.

The Hoki fish found in the southern sea of New Zealand is one of the best sources of deep sea fish oil. It is rich in omega-3 fatty acids and contains a lot of DHA and EPA. These are the two Omega 3 fatty acids that are the most important for the human body.

The Hoki fish swims in the cleanest and freshest deep waters on Earth. The southern sea is regulated and protected by the government of New Zealand, so that clean sources of deep sea fish oil are available for the future generations to come.

If we look at deep sea fish oil manufacturing from an environmental angle, we can find a lot of problems with the other types of fish that are used for supplements. If we just look at a single case, the Atlantic cod fish has been an over-fished population and has been managed very poorly. Their fishing using bottom trawls damages their natural habitat and severely affects their population.

The Hoki fish found in the cold deep oceanic waters in the southern coasts of New Zealand is a sustainable natural resource due to the regulation of the government of New Zealand. This is the reason why New Zealand is one of the few nations that has gained a reputation of being a “green, clean” heaven.

Another important thing that you should consider while looking for the most effective deep sea fish oil is that it should be pharmaceutical grade products. This means that they have undergone the process of molecular distillation. It is the one and only way to ensure that all contaminants such as Mercury, lead and PCBs have been removed from the fish oil.

Also make sure that the product specifies clearly the breakup of Omega 3 fatty acids and DHA and EPA contents. A majority of the fish oil supplements only specify the omega-3 fatty acids contents.

Visit my website to find out in greater detail about the essential elements you should look for in the best deep sea fish oil supplements. Find out how fish oil can work wonders in your health and can give you a sharp mind and a healthy body most effortlessly.

Natural cosmetics represent the best choice since they are chemical-free and they help us maintain a radiant, healthy skin. Premier Dead Sea cosmetics can be certainly the most important of high quality Dead Sea products. They offer a unique line of products exported in more than thirty countries and they have an ample, positive renown for the beneficial properties of their products.

Premier Dead Sea products facilitate the renewal process of the skin, by simulating the epidermal cells and restructuring the balance of the skin. Premier Dead Sea cosmetics penetrate the skin immediately, they provide it with a vital source of energy and they do not have an oily aspect. By using these products, your skin will be healthy and nurtured.

Premier Dead Sea cosmetics form the object of international marketing and they contain the best natural ingredients, being rich in salts and minerals. These ingredients are only identifiable in Israel’s Dead Sea and experts extract them from soil and water. The formulae developed by these experts are famous for their rejuvenating and renewing properties of the skin. The results of these Premier Dead Sea products are amazing and noticeable.

Premier Dead Sea cosmetics include products for face, skin and hair care. This Israeli company has managed to embody the therapeutic and rejuvenating properties of the Dead Sea in its products. This line of products also provides us with scrubs, bath salts, shampoos, mineral soaps and mineral care products, with a unique composition. All these Premier Dead Sea products are based on natural formulae and have undergone clinical tests.

All these products contain SPF 17 and they are based on eight components that ensure a long-lasting effect of the creams, lotions and ointments. Premier Dead Sea products come in attractive packages that are recyclable, all the ingredients being ozone friendly. These cosmetics are not tested on animals.

Premier Dead Sea cosmetics combine the rejuvenating minerals of the Dead Sea with herbal extracts and aromatic oils, thus restoring to your skin its elasticity and firmness. These products do not contain any sort of artificial or dye materials, being entirely natural. Their unique composition based on natural ingredients makes them the most frequent choice for people all over the world. These cosmetics are exported on a regular basis in countries such as France, Spain, United States, and Brazil, Japan and others, being famous for their efficiency.

The Dead Sea is a marvelous place that has been promoting a healthy environment for thousands of years. In this respect, it has offered unique health-friendly ingredients. Nowadays, people are aware of the benefic effects of salts and minerals and they try to find natural cosmetic products that, unlike other cosmetics, have no secondary effects for their skin.

Premier Dead Sea products have a high composition of minerals and salts, acting directly on your skin and making you proud of it. Due to their unique composition, these products have managed to attract people from all over the world and to receive appreciation for their positive effects.

Dead Sea Products are creating a lot of enthusiasm in people in recent times. Now a days most of the companies market the products like dead sea facials, massages, body wraps and excess of other goods. The product is being utilized very nicely by some people in their daily life, even though they do not know the worth of the product.

Many people are unaware of the celebrity and legendary Cleopatra. She is very passionate about these Dead Sea products. Her beauty secret is been hidden and later gossiped that she used all these Dead Sea blends and lotions. Now a days, most of the companies are marketing through out the world with these dead sea products made out of salts and minerals. There is no need for the people to travel to Dead Sea because the products are getting promoting through out the world.

The Dead Sea is not a normal sea it looks like a lake with mixture of salts and minerals and it is lowly lying region in out planet. Because of this salts there will be high density of water, which makes all the organisms die. And you can in fact float on water without life jacket due to high water density. Researchers have extorted minerals like Calcium, Potassium and Bromide and prepared them into products which will be a substitute to the minerals and nutrients that we lost from our body due to bathing and too much pollution and dust which make our skin parched and peeling. Because of this people end up with skin problems, acne and pimples.

The Dead Sea cosmetics and products help to alleviate these skin problems since they are quite rich in minerals and antioxidants. These minerals help in skin healing and revival. Moreover, the Dead Sea products also aid in stimulation of collagen, creams that reduce and remove cellulite and fighting acne, eczema and psoriases. They also help in reducing wrinkles and the ill effects of aging.

Dead Sea mud masks are also quite a rage amongst the rich and the famous these days. These mud masks play the combined role of a moisturizer, cleanser and a toner. They also help in wrinkle reduction. Beauty expert’s advice that it is essential to use an exfoliating sea salt before the application of the mud mask. There are Dead Sea kits available that can help in cleansing, toning and can comprise of all the lotions and the salts made of Dead Sea minerals.

So the people who are overwhelmed with skin problems can use a good combination of Dead Sea mud. The skin problems like acne will be removed with Dead Sea mud along with the aging marks and blotches. Dead Sea cosmetics are safe and familiar to use evenly on particularly sensitive skin. Nevertheless before trying these products you can always consult a beautician or a skin expert.

Both the men and women can utilize these Dead Sea products. The after shave lotions are mostly chosen by most of the men which are made of Dead Sea minerals. Not only are these lotions, many Dead Sea creams used to reduce the problems like calluses and other concerns of men.

The Dead Sea region offers a rare combination of nature sites, history and unique healing centers, each of which has the potential to inspire autonomous tourism development. The Dead Sea, at approximately 417 meters below sea level, is the lowest point on the surface of the earth. It is a remnant of the ancient “Lake Lisan”, the body of water which once extended from the north of the Sea of Galilee to Hazeva in the Arava.

The water’s salinity, with a concentration of about 340 grams per liter (10 times that of the Mediterranean!), makes floating natural and effortless and instills a sense of peace and tranquility. The air is dry, rich in oxygen and free of any environmental pollution, and the temperatures are relatively high, even in the height of winter. The fact that the sun’s harmful ultraviolet rays are naturally filtered makes it possible to sunbathe without burning and is instrumental in treating various skin diseases. The natural “healing waters” along the coast, which are rich in minerals and natural heat, combined with the black mud deposits, are the ideal foundation for health and beauty treatments.

The region’s nature reserves and scenic diversity offer a unique combination of arid desert vistas and oases alongside pools and waterfalls teeming with diverse flora and fauna (mountain goats, pikas, insects, reptiles, various species of fowl, etc.). The region’s historical sites are among the most renowned in the world, namely: Massada, Qumran, Jericho, Ein Gedi, the Roman fortresses and the monasteries in the Judea Desert.

A great many resources are invested in developing infrastructures, facilities and services dedicated to the tourist industry. The region offers about 4,000 rooms in hotels of various standards, kibbutz resort villages, hostels and other accommodation facilities, with adjacent services such as: parking lots, public beaches, well-kept nature reserves and fascinating tourist sites. The vacationers and tourists in the region can choose from a wide variety of excursions and activities, including desert tours on foot, in special vehicles and on camels, Bedouin accommodation, rock climbing and rappelling courses and excursions, as well as archeological and agricultural tours.

SOURCE OF LIFE AND HEALTH

A unique combination of natural resources having therapeutic effects has turned the Dead Sea area into a healing center unparalleled anywhere else on the face of the earth.

The salty seawater, with its unusually high concentration of minerals, the natural hot springs rich in minerals and sulphur, and

the extraordinary climatic conditions, including uniquely filtered sun rays and an oxygen-rich dry air, due to the high barometric pressure prevailing here in the lowest spot on earth (417 meters below sea level), a therapeutic black mud – all combine in providing the basis for the successful effect of the Dead Sea therapies.

Contributing to these ideal therapeutic conditions are the comfortable stable temperatures in this seaside desert most of the year, the pure unpolluted air, which is free of allergens and contaminants, while containing minerals deriving from evaporation of this inland sea that are healthy for breathing.

These natural resources have been shown to provide a beneficial effect on various illnesses, including chronic incurable diseases, and have led to the renowned reputation of the Dead Sea area as a natural spa constituting a source of promoting health and improving the quality of life.

For some 2,000 years (as the ancient texts attest), people have come to immerse themselves in the Dead Sea for healing purposes. The awareness of the healing attributes of the Dead Sea was truly reawakened at the beginning of the 1970s, when the scientific research studies in the area gained momentum and their findings were published.

All this recognition led to an accelerated development of hotel facilities, along with the establishment of health and therapy centers, operating on the basis of scientifically based findings, which as a result have turned the Dead Sea area into an attractive internationally recognized healing center, drawing each year tens of thousands of patients from around the world to find relief for their ailments and pains.

THE DEAD SEA EFFECT

The accumulated clinical experience and research data on all aspects of climatic therapy, which is based on a combination of exposure of the body to the sun with an immersion in the Dead Sea waters, has enabled physicians to establish a protocol of treatment methods referred to as “Dead Sea Climatotherapy.”

Medical and scientific research studies indicate that Dead Sea Climatotherapy is very effective in treating numerous illnesses, the most common being the skin disease, psoriasis. Dead Sea climatotherapy has also been found to have therapeutic effects on atopic dermatitis (skin allergy), vitiligo (loss of pigmentation), and early stage mycosis fungoides (skin cancer).

Natural springs containing minerals and sulphur, black medicinal mud, with antibacterial activity and hyperemic properties, are also found along the shores of the Dead Sea.

An anti-aging effect discovered recently in the Dead Sea minerals, as well as in the medicinal mud, has made the Dead Sea even more popular, attracting people who seek to slow down their skin aging process.

As opposed to the artificial treatments administered in the conventional clinic or hospital environment, the relaxing atmosphere during Dead Sea climatotherapy, where patients mix socially with other guests in a hotel atmosphere, has often been shown to have psychological benefits, by providing a positive affect on the patients’ self image and, as a result, on his or her quality of live.

THE DEAD SEA TREATMENT

The beneficial effects of Dead Sea climatotherapy on dermatological diseases, such as psoriasis, eczema, lichen planus and vitiligo, have been amply documented in a multitude of scientific publications over the past 40 years.

These studies have established that optimum results in the treatment of psoriasis, for example, are achieved by a short-term immersion in the Dead Sea water, followed in most cases and depending on the time of the year by a 1½-2½ gradual exposure to the sun once in the morning and once in the afternoon. Winter is not recommended for this kind of disease.

A rooftop meteorological station on the southwestern shore of the Dead Sea performs continuous UV monitoring and provides online data on the intensity of the daily solar ambient radiation. Studies with radiosensitive detector badges placed on the body have been conducted recently to determine the actual amount of radiation absorbed by sunbathers.

A special computerized program is installed in the solarium at Ein Bokek, enabling patients to regulate their initial daily exposure time by themselves, based on their skin type and the radiation intensity measured during exposure.

The actual amount of energy to which the patient’s body is exposed by these schemes is about one third of the amount applied in artificial irradiation therapy regimes, yet the therapeutic results of the Dead Sea natural treatment lead to a 80-90% remission, comparing favorably with artificial irradiation modes. The mean duration of remission has been studied in 64 German psoriasis patients and found to last on the average six months.

The Effects of Dead Sea Climatotherapy on the Pathogenesis in Psoriasis

A study published in 2003 examined the effects of Dead Sea climatotherapy on the pathological changes and immunological modulation in psoriatic patients’ skin.

Histological examination of the skin found that the characteristic pathological changes found in psoriasis had normalized, while immunological studies showed a major reversal in immunological activation.

Preliminary data show that optimum results in clearing psoriatic lesions were achieved faster when Dead Sea climatotherapy is combined with topical administration of calcipotriol.

Repeat studies have shown that even severe forms of psoriasis, which otherwise require hospitalization and often need systemic medications, such as oral retinoids, methotrexate or cyclosporine, respond remarkably to climatotherapy, let alone milder forms, all without the potential side effects often associated with the administration of these systemic medications.

Dead Sea Climatotherapy is subsidized by sick funds and national health agencies: A study performed by the Swiss Psoriasis Association has shown that economically, while being equally effective as artificial treatments given to severely affected psoriasis patients, Dead Sea climatotherapy is less expensive when comparing overall expenditures for both modes of therapy.

In view of its cost effectiveness, health funds in Western European countries, such as Germany and Denemark, as well as in several Eastern European countries, subsidize Dead Sea climatotherapy for skin diseases, while Norway also subsidizes Dead Sea treatments for joint diseases.

By negligently discarding plastic, especially plastic water bottles, fishing gear and plastic bags, people are unknowingly causing the deaths of millions of mammals, fish, birds and reptiles every year.

We defile the face of the earth with plastic refuse. Since the invention of plastic earlier this century, it has become a popular material used in a wide variety of unique and innovative applications. Plastic is used to make, or wrap around, many of the items we buy or use. The problem comes when we no longer want these items and how we dispose of them, particularly the throwaway plastic material used in wrapping or packaging. Plastic is handy, lightweight and easily discarded. Too easily discarded.

Plastics are not themselves the problem. They are useful materials which can be produced with relatively little damage to the environment. The problem is the excessive use of plastics in one-time applications together with careless disposal.

Take a look around you. Plastic bags can readily be seen hanging from the branches of trees, flying about on windy days, settled amongst grasses and floating on streams. They clog up drains causing water and sewage to overflow and become the breeding grounds of germs and bacteria that spread disease.

Plastics are utilized because they are easy and inexpensive to manufacture, strong and durable. Unfortunately these same useful qualities make plastic an overwhelming pollution problem. Inferior quality and low cost means plastic is readily discarded. Plastics take around 300 years to photo degrade. Plastics long life assures it survival in the environment for extended periods where it can do great harm. Because plastic does not easily decompose and requires high energy ultra-violet light to break down, the volume of plastic waste in the world?s oceans is steadily increasing.

Plastic is now found in virtually all the oceans and rivers of the world, even the most remote and once pristine.

American oceanographer Charles Moore says the amount of plastic pollution in the worlds oceans is so extensive it?s beyond cleaning up. A toxic plastic ?graveyard? double the size of Texas swirls in the waters of the Pacific between San Francisco and Hawaii. There his crew found that the water contained over 40 parts of plastic for every part plankton, with a fivefold increase in the amount of plastic between 1997 and 2007.

Annually approximately 500 billion plastic bags are used worldwide. That is an unconscionable amount of waste, so much that more than one million bags are used every minute and their impact on the planet is devastating. Plastic bags are only part of the problem. America alone, yearly produces in excess of 800,000 tons of plastic bottle pollution. World-wide our precious planet is defaced and poisoned with more than 100 million tons of plastic pollution annually.

According to the California Costal Commission, over 80% of refuse within waterways, most of it being plastic, originates on land rather than coming from boats.

Plastic affects marine wildlife in deadly ways: entangling creatures and by being consumed.

Turtles are particularly devastated by plastic pollution. All seven of the world’s turtle species are already endangered or threatened for a multitude of reasons. Turtles become entangled in plastic fishing nets, and many sea turtles have been found dead with plastic garbage bags in their stomachs. Studies indicate turtles mistake these floating semi-transparent bags for jellyfish and eat them. The turtles die an inhumane death from choking or from being unable to eat. A dead turtle found off the coast Hawaii was found to have more than 1000 pieces of plastic in its stomach including part of a comb, a toy truck wheel and lank of nylon rope.

There is great environmental concern about the effect of plastic trash on all marine mammals. These elegant creatures are already under threat for a variety of other reasons: e.g. seal and whale populations have been decimated by unregulated hunting. A recent study concluded that in excess of 100,000 marine mammals die needlessly each year from the deadly effects of plastic pollution.

World-wide over 100 bird species are known to ingest plastic particles. This includes 36 species found off the coast of South Africa. A recent study of blue petrel hatchlings at South Africa’s remote Marion Island showed that 90% of the chicks examined had plastic in their digestive systems, apparently fed to them accidentally by their parents. South African seabirds are among the worst affected in the world. Plastics remain in the bird?s stomachs, impeding digestion and causing starvation.

Scientific studies are not conclusive about how much plastic birds and fish are consuming, however scientist agree that plastic in seafood is likely to be harmful for people. Plastic is compared with better understood toxic materials such as mercury. Plastic acts like a sponge when in contact with poisons such as PCBs, concentrating them at levels that are millions of time more than in seawater.

The ingredients in plastic have been linked to cancer and reproductive abnormalities. Bisphenol A, found in plastic water bottles, has been shown to produce cancer in lab rats, to disrupt hormone levels and is associated with diabetes and obesity.

Scientists also voice concerns that the massive swirls of floating plastic could contribute to global warming by creating a dense shade canopy that makes it difficult for plankton to grow.

“When you defile the pleasant streams and the wild bird’s abiding place, you massacre a million dreams and cast your spittle in God’s face.” ~ John Drinkwater

Let?s look at a few different ways where ?Together We Can Make A Difference?.

The crisis of plastic pollution demands urgent study and action. Businesses should be encouraged to reduce the amount of plastic used in packaging and to re-cycle.

Plastic wrapping and bags should be required to carry a warning label advising of the dangers of plastic pollution and shoppers should be encouraged to use eco-friendly shopping bags of organic, natural materials or recycled plastic fibers. Tell this to our law makers. The situation only continues to worsen. We must act now!

When a tax levy was imposed on plastic bags in Ireland, usage dropped by 90 percent. Several other countries have already banned the use of plastic bags with significant impact. America must follow their example. Support re-cycling programs and promote environmental awareness in your local community. Be pro-active in asking governments to make changes and consumers to re-think their attitudes. Purchase products requiring less plastic packaging and inform store management why you are doing so. We can speak with a loud voice when we speak with our ?dollars?.

Choose to drink tap or carbon filtered water from a glass lined reusable container. If you do purchase plastic bottled, dispose to the container properly. Recycle.

With the increase in environmental awareness, it has become obvious that there is more that we can do to create a sustainable society. If everyone of us would take a few tiny steps, make a few different choices and consciously consider our impact on the planet, there might be a way to restore the world to its original beauty and resources.

Join us in protecting the diversity and quality of our environment. We can all contribute to a healthier, greener world.