Wednesday, December 31, 2008

Spectacular Moon-Venus conjunction on Wednesday.

Spectacular Moon-Venus conjunction on Wednesday
by
Dr. Nitish Priyadarshi
The two brightest objects in the night sky, Venus and Moon, is seen today (31/12/2008)above the Ranchi city of Jharkhand State. Conjunction is a term used in astronomy for the relative positions of celestial bodies.

Thursday, December 25, 2008

Air pollution threats Ranchi city of Jharkhand State, India.

Air pollution threats Ranchi city of Jharkhand State, India.
by
Dr. Nitish Priyadarshi

We are already seeing the effects of air pollution in Ranchi city the capital of Jharkhand State of India. It has also affected the climate. From last several years Ranchi is facing extremes of the climate. In year 2005and 2006 Ranchi had spells of excessive rainfall. In the month of February and March 2007 Ranchi faced heavy rainfall followed with hail storms which is unusual in Ranchi at this time. We have faced extremes of climate in very quick interval this year till now.

In 1960's and 1970's peoples of Ranchi (the then summer capital of Bihar Jharkhand united) rarely used fans even in summer seasons. This facts can be justified by the following statements published in Ranchi Gazetteers in the year 1970- " The climate of the Ranchi plateau is cool and pleasant. It is only during the month’s of April or May that the temperature rises occasionally. The general elevation of 2,180 feet above sea level gives it a uniformly lower range temperature than the plains."

Three decades ago Ranchi was known for its healthy climate. People from the surrounding states use to visit Ranchi and its neighbouring places for their health benefit. That time Ranchi was known for its clean air and very less pollution. Motor vehicles, the major source of air pollution, were less. In my childhood I remember that I use to count the vehicles on my fingers.

Now the Ranchi air has become highly polluted. Children are suffering from different lungs diseases. Eyes burning while driving scooter or even walking, is now a very common phenomenon. Toxic gases emitted from the automobiles are increasing many folds. Lots of trees have also been cut down for making houses, marketing complexes etc. Due to thin vegetation Ranchi is under the grip of dust pollution. Due to the dust pollution sky above the Ranchi looks pale yellow. At night very few stars are now visible. I remember when I was a child I used to admire and imagine all the stars. Sky was so neat and clean.
Most of the houses now build in Ranchi are not properly ventilated. A lack of ventilation indoors concentrates air pollution where people often spend the majority of their time. Radon (Rn) gas, a carcinogen, is exuded from the Earth in certain locations and trapped inside houses. Building materials including carpeting and plywood emit formaldehyde (H2CO) gas. Paint and solvents give off volatile organic compounds (VOCs) as they dry. Lead paint can degenerate into dust and be inhaled. Intentional air pollution is introduced with the use of air fresheners, incense, and other scented items.

An air pollutant is known as a substance in the air that can cause harm to humans and the environment. Pollutants can be in the form of solid particles, liquid droplets, or gases. In addition, they may be natural or man-made.

In this article I am going to discuss some of the major sources of air pollution in Ranchi city.
Following are the major sources of air pollution in the city.

1. Transportation.
2. Solid waste combustion.

Transportation:
After the formation of Jharkhand motor vehicles have increased many folds. Ranchi topped the list of increase in vehicle registrations in 2001-2002, the largest in buses, cars, taxis, jeeps, two-wheelers and three wheelers were recorded in Ranchi. Transportation (cars, trucks, buses etc.) is responsible for a significant percentage of criteria pollutants, such as Sulfur dioxide, Nitrogen oxides, Volatile organic compounds, Particulates, Carbon monoxide and Lead.
Emissions from an individual car are generally low. Average emission of carbon monoxide from the two wheelers varies from 0.04% to 0.10% and average emission of hydro carbons was 500 ppm in Ranchi city. But emissions from thousands of vehicles plying in the streets of Ranchi city add up, making the automobile the first greatest polluter. Main problem is with old cars especially diesel operated. In fact, driving a car is probably a typical citizen’s most “polluting” daily activity.

The sources of Automobile Emission:

The power to move an automobile results from burning fuel in an internal combustion engine. Pollution from automobiles comes from by-products of this combustion process (exhaust) and from evaporation of the fuel itself.
Fuel is burned in the cylinder of an internal combustion engine at very high temperatures (1500 degree F.). At such high temperatures, atmospheric nitrogen and oxygen combines to form nitrogen oxides, and hydrocarbons from un-burnt fuel, carbon monoxide from incomplete combustion, and carbon dioxide are formed. All these major pollutants are then emitted as exhaust gases into the atmosphere. In addition, the combustion of gasoline additives produces minor amounts of pollutants, such as 1,3-butadiene, benzene, formaldehyde, acetaldehyde, and particulate matter, especially from diesel engines.
Concerning evaporative emissions, hydrocarbon pollutants escape into the air through fuel evaporation, which accounts for as much as 65 percent of the total hydrocarbon pollution from current model automobiles. Fuel evaporates most readily in hot weather, and fuel evaporation occurs in several ways, including:

· Daytime evaporation.
· Running losses.
· Hot soak.
· Refueling.

Gasoline vapors are always present in the fuel tanks. These fumes are forced out when the tank is refueled. In addition, gasoline vapors are emitted from the gasoline pump’s nozzle during the refueling. It not only affects the air quality but also the health of the consumers and people residing near this gasoline station. Peoples leaving near the gasoline station in Ranchi city always complain about the foul smell, nausea and giddiness. It is due to the fumes which are forced out by the owners when the tank is refueled. In above figure two wheeler is being checked for carbon monoxide emission

Solid Waste Combustion:
The emissions from solid waste combustion include carbon monoxide, particulate matter, nitrogen oxides, volatile organic compounds, mercury, lead, hydrogen chloride, and minor amounts of chlorinated dioxins.
In Ranchi many areas looks like dumping ground of municipal wastes and house hold wastes. It has also been seen that these toxic wastes are burned in an open air. Open Burning" of solid waste degrades the air quality. Harmful toxins may also be released. Open burning produces unsightly and odorous smoke. Low wind speeds during these hours further compound the problem.

Wastes deposited beside the city rivulets poses more threat to environment. These wastes contain large amounts of plastics and medical wastes. Most people who burn their plastic domestic waste do not realize how harmful this practice is to their health and to the environment. Current research indicates that backyard- burning of waste is far more harmful to our health than previously thought. It can increase the risk of heart disease, aggravate respiratory ailments such as asthma and emphysema, and cause rashes, nausea, or headaches, damages in the nervous system, kidney or liver, in the reproductive and development system. The burning of polystyrene polymers -such as foam cups, meat trays, egg containers, yogurt and deli containers -releases styrene. Styrene gas can readily be absorbed through the skin and lungs. At high levels styrene vapor can damage the eyes and mucous membranes. Long term exposure to styrene can affect the central nervous system, causing headaches, fatigue, weakness, and depression.
Not only these people who are burning the trash are exposed to these pollutants,
but also their neighbours, children and families.

The most dangerous emissions can be caused by burning plastics containing organoch-
lor-based substances like PVC. When such plastics are burned, harmful quantities of
Dioxins, a group of highly toxic chemicals are emitted. Dioxins are the most toxic to the
Human organisms. They are carcinogenic and a hormone disruptor and persistent,
and they accumulate in our body-fat and thus mothers give it directly to their babies
via the placenta. Dioxins also settle on crops and in our waterways where they eventu-
ally wind up in our food, accumulate in our bodies and are passed on to our children.



Wednesday, December 10, 2008

Diesel Generators poses serious health hazard in Ranchi city of India.

Diesel generators poses serious health hazard in Ranchi city of India.
by
Dr. Nitish Priyadarshi



In recent years the shortage of power coupled with unreliable and poor quality of the power supply has resulted in a proliferation of captive generator sets, run with either diesel, petrol or kerosine, as an alternate source of power. This is happening, particularly, in urban areas where the need is greater. Unfortunately, in most of these places there is an overlap of commercial, residential and industrial areas which together with poor planning for the installation of generator sets and absence of any acoustic treatment/enclosure, leads to excessive noise pollution.

In the photograph you can see one generator being kept in a very densely populated business area in heart of the Ranchi city, the capital of Jharkhand State. In the background you can also see the food stall where the green vegetables are used for popular Chinese foods. Possibilities of deposition of the smokes and dust containing toxic gases and particulates on the vegetables and Chinese food is high. People consuming these foods are at the higher risk of developing different health diseases. Even the local shopkeepers are under threat of different lungs diseases. These generator runs on an average for 4 to 7 hours a day during peak hour. This is not only one case in Ranchi there are several other numerous spots in Ranchi city where diesel operated generators are being used in an open space.
It is not only creating air pollution but also noise pollution.

A typical standby diesel generator produces 25-30 pounds of nitrogen oxides (NOx) per megawatt hour of power generated. Nitrogen oxides are a smog-forming pollutant. Diesel is produced from a fossil fuel and engines using it as a fuel produce air pollution and high sulfur levels. Diesel fuel also creates a distinct smell and exposure to diesel engine exhaust can also lead to health hazards.
Diesel emission levels of NOx, carbon monoxide (CO), hydrocarbons, and particulate matter were a substantial contributor to poor air quality.
The visible pollution generated by burning diesel contains elemental carbon.
And the smell comes from a group of particles called polycyclic aromatic hydrocarbons, well-known cancer causing agents.
How effective are air pollution diesel emissions as a carcinogen? They were found to cause of up to 70 percent of atmospheric pollution induced cancer cases.
In one study, volunteers who allowed themselves to be exposed to diesel fumes reported coughing, sore throat and eyes, , headaches , and nausea. Some came down with lung inflammation after exposure.
Other common symptoms included the production of phlegm and difficulty breathing. Of course, people also complained about odors. A perpetual annoyance.
Fine particulate matter (PM) in diesel exhaust can by pass the body’s natural defenses penetrating deep into the lungs where it may cause or exacerbate respiratory and cardiovascular illnesses, and even premature death.

Nitrogen oxide (NOx) emissions from diesel engines contribute to smog formation which has been linked to increases in hospital admissions for asthma and is most
dangerous to children, the elderly, and those with pre-existing respiratory and cardiovascular disease. NOx emissions also react with other air pollutants to increase the level of particulates in the air.

Saturday, December 6, 2008

Rocks of Ranchi city in India is radioactive.

Are the rocks of Ranchi city in India is Radioactive?
by
Dr. Nitish Priyadarshi







Ranchi is the capital city of the Indian state of Jharkhand.  / The total area covered by Ranchi - Municipal Area is about 110 square kilometers and the average elevation of the city is 2,140 feet above sea level.
Geographically, Ranchi is located on southern part of the Chota Nagpur plateau which forms the eastern edge of the Deccan plateau system. The area surrounding Ranchi has been endowed with natural attractions and it is referred to as the “City of Waterfalls”.
As of 2001 India census, Ranchi had a population of 846,454. Males constitute 53% of the population and females 47%.

Rocks around Ranchi:

The oldest geological formation of this district is represented by Dharwar sediments with the basic intrusive. These, being later intruded by the batholithic mass of Chota Nagpur granite, were metamorphosed into various types of schistose and gneissic rocks. The remnants of the earlier sedimentary and igneous rocks are known from the inclusions of phyllites and schists of varying dimensions in the granite mass and the extensive areas of Khondalites. Phyllites are by far the predominant rock type in the south-east portion of this district. Chota Nagpur granite gneiss forms the country rocks of the district and is a part of the enormous intrusive mass.

Within the main body, the granite gneiss varies from a normal medium- grained rock to a porphyritic material with large crystals of potash feldspar. Quartz, biotite or hornblende are the other essential minerals. Apatite, zircon, sphene are rutile are the accessories. The amphibolites occur as minor intrusive in the Khondalite series. Amphibolite also occur as minor enclaves in the granite gneisses in and around Ranchi city.

Radioactivity in the Environment:

Humans have always been exposed throughout their period of existence to naturally occurring ionising radiation. Specifically, naturally occurring radionuclides are present in variable amounts in our environment. To assess radiological health hazards, naturally occurring radionuclides are being measured in soil, sand, marble, bricks etc throughout the world.

Terrestrial radiation comes from radioactive elements that were present at the time the earth was formed. They continue to decay and form additional radioactive materials.
Unusual soil composition has increased background radiation twenty-five fold or more in a few areas in the world. Locations with high background radiation in the soil, mainly from uranium, include the Rocky Mountains, Kerala India, coastal regions of Brazil, granite rock areas of France, and the northern Nile Delta.
In the United States, lower background radiation is seen in the sandy soils of the Atlantic and Gulf coastal plains.


The distribution of naturally-occurring uranium, radon, and other radioactive elements, radionuclides, depends on the distribution of rocks from which they originate and the processes which concentrate them. The key therefore is to know the distribution of source-rock materials containing elevated levels of radionuclides and to understand the physical and geochemical processes that concentrate radionuclides."

Gamma and alpha radiation emitted by radioactive elements in rocks and soils, especially those that decay quickly (such as radon), pose a health risk. This radiation is implicated in cancers of the lung, bone, and of other organs.

Radioactivity generated by those radioactive elements that exist in the Earth's crust. All the elements from polonium (atomic number 84) to uranium (atomic number 92) are radioactive. Radioisotopes of some lighter elements are also found in nature (for example potassium-40).

Radioactive gases such as radon are found in soil and may seep upwards into buildings.

Radioactivity in Ranchi soil:

Seeing the rock types and its mineral composition background or radioactive radiation cannot be ruled out in Ranchi. This fact was justified by a published report of Research Reactor Institute, Kyoto University. According to the report Air-gamma dose rate was 0.30 μSv/h on the surface in the densely populated area in the city. In Ranchi the concentration of K-40 (potassium-40) and thorium is high. Concentration of Radium-226 was 75 Bq/Kg in the soils.

Very interesting thing in the Ranchi city is that name of one of its major road is RADIUM ROAD. Till today no body knows from where did this name came from. Name of this road exists from the British rule in India i.e. before 1947.

Potassium 40 is found in potassium feldspar (orthoclase), muscovite, and amphibole.
Uranium may be found in zircon ,urananite ,monazite ,apatite and sphene . Seeing the presence of apatite, sphene and zircon in the Ranchi rocks, presence of Uranium cannot be ruled out. According to the report Uranium concentration is also high in Ranchi. All these concentrations are of natural origin. Radioactivity in the bricks made by the local soil may pose threat to the people living in the houses made by these bricks.

When Uranium is there, presence of Radon cannot be ruled out. It is radioactive gas that comes up from the soil and collects in basements and ground floors, sometimes in well water. Radon is a prominent villain in the United States, blamed for tens of thousands of deaths from lung cancer.

Radon is relatively high in uranium-rich rocks such as ancient granites, like Ranchi, high-organic shales and coal beds.

There are areas in the world where the content of the uranium or thorium in soil are high, and the people are receiving exposure of 10 or more times in such a place compared with other areas. There is no other way but to accept. Ranchi, the capital of Jharkhand, is one of such the places.

Health effects:

Potassium-40 can present both an external and internal health hazard. In the body, potassium-40 poses a health hazard from the both the beta particles and gamma rays. . The health hazard of potassium-40 is associated with cell damage caused by the ionizing radiation that results from radioactive decay.

There is no evidence that exposure to naturally present levels of radium has harmful effects on human health. However, exposure to higher levels of radium may result in health effects, such as teeth fracture, anaemia and cataract.

Radium is constantly produced by the radioactive decay of uranium and thorium. Radium is present at very low levels in rocks and soil and strongly attaches to those materials. It is also found in air. High concentrations of radium exist in water on some locations.Uranium mining results in higher levels of radium in water near uranium mines. Plants absorb radium from the soil. Animals that eat these plants will accumulate radium.Finally, radium may concentrate in fish and other aquatic organisms and bio magnify up the food chain.
People will always be exposed to small amounts of thorium through air, food and water, because it is found nearly everywhere on earth.All people absorb some thorium through food or drinking water, and the amounts in air are so small, that the uptake through air can usually be ignored. Breathing in thorium in the workplace may increase the chances of development of lung diseases and lung and pancreas cancer many years after people have been exposed. Thorium has the ability to change genetic materials.
Seeing the high concentration of thorium (210 Bq/kg) people of Ranchi may face some thorium exposures.

Conclusion:
Even the exposure in Ranchi city may be of very low dose, exposure to radiation accompanies risk. However, since the natural activity exists on the earth and there is a radiation such as a cosmic ray, we cannot escape the exposure completely. Seeing the possibilities of Radon gas, houses built in Ranchi should be proper ventilated and making of basements should be avoided.

Reference:

Priyadarshi, N. 1998. A handbook geology of Chotanagpur, Aoyushi Publications, Ranchi, India.

http://encyclopedia.farlex.com/natural+radioactivity

http://encyclopedia.farlex.com/background+radiation