Table of Contents
- 1 Radioactive Pollution
- 1.1 Sources
- 1.2 Effects of Radioactive pollution
- 1.3 Ionizing and Non-Ionizing Radiation
- 1.4 Accidents at nuclear power plants
- 1.5 Safe Disposal Of Nuclear Wastes
- 1.6 Preventive/Control Measures
- 2 Impact Of Radiation From Mobile Phone Towers
- 3 Soil Pollution
- 4 Noise Pollution
Artificial Sources of Radioactive pollution
- Accidents in nuclear power plants and nuclear waste.
- Nuclear weapon testing and explosion (Nuclear fallout). The fall Out contains radioactive substances such as strontium-90, cesium-137, iodine-131, etc.
- Uranium mining and mining of other radioactive material like thorium Uranium contamination is well observed in India.
- Radiation therapy and direct exposures to radiation for diagnostic purposes (e.g. X-rays), chemotherapy etc.
- The slow nuclear radiations can emanate from a variety of sources viz. nuclear reactors, laboratories, hospitals, and direct exposures to X-rays etc.
- They include cosmic rays from space and terrestrial radiations from radio-nuclides present in earth’s crust such as radium-224, uranium-238, thorium-232, potassium-40, carbon-14, etc.
- Some species of animals and plants preferentially accumulate specific radioactive, materials. For example, oysters deposit 65Zn, fish accumulate 55Fe, marine animals selectively deposit 90Sr.
- The use of nuclear energy has two very serious inherent problems.
- accidental leakage, as occurred in the Three Mile Island, Chernobyl and Fukushima incidents and
- safe disposal of radioactive wastes. It has been recommended that storage of nuclear waste, after sufficient pre-treatment, should be done in suitably shielded containers buried within the rocks, about 500 m deep below the earth’s surface. However, this method of disposal is meeting stiff opposition from the public.
- The quick devastating and immediate effects of nuclear radiations are well known as witnessed following Hiroshima and Nagasaki in Japan during world war II.
- Continued small dose exposure to nuclear radiation can cause childhood leukemia, miscarriage, underweight babies, infant deaths, increased susceptibility to AIDS and other immune disorders and increased criminalities.
- Underground bomb testing releases radiations in very small doses of radicals that pollutes water and soil.
- This radioactive water is taken by plants through roots. The radioactivity enters food chain when such plants are eaten by animals and humans. Such radioactivity has been detected even in the milk.
- Radiation, that is given off by nuclear waste is extremely damaging to biological organisms, because it causes mutations to occur at a very high rate.
- At high doses, nuclear radiation is lethal but at lower doses, it creates various disorders, the most frequent of all being cancer.
- Radioactivity is a phenomenon of spontaneous emission of proton (alpha-particles), electrons (beta-particles) and gamma rays (short wave electromagnetic waves) due to disintegration of atomic nuclei of some elements. These cause radioactive pollution.
- Radiations can be categorized into two groups namely the non-ionizing radiations and the ionizing radiations.
- Non-ionizing radiations are constituted by the electromagnetic waves at the longer wavelength of the spectrum ranging from near infra-red rays to radio waves [include higher wavelength ultraviolet rays, microwaves].
- These waves have energies enough to excite the atoms and molecules of the medium through which they pass, causing them to vibrate faster but not strong enough to ionize them.
- In a microwave oven the radiation causes water molecules in the cooking medium to vibrate faster and thus raising its temperature.
- They may damage eyes which may be caused by reflections from coastal sand, snow (snow blindness) directly looking towards sun during eclipse.
- They injure the cells of skin and blood capillaries producing blisters and reddening called sunburns.
- Ionizing radiations cause ionization (one or more electrons are pealed out from the outer shells of an atom) of atoms and molecules of the medium through which they pass.
Ionization is the process by which an atom or a molecule acquires a negative or positive charge by gaining or losing electrons to form ions, often in conjunction with other chemical changes.
- Electromagnetic radiations such as short wavelength ultra violet radiations (UV), X-rays and gamma rays and energetic particles produced in nuclear processes, electrically charged particles like alpha and beta particles produced in radioactive decay and neutrons produced in nuclear fission, are highly damaging to living organisms.
- Electrically charged particles produced in the nuclear processes can have sufficient energy to knock electrons out of the atoms or molecules of the medium, thereby producing ions.
- The ions produced in water molecules, for example, can induce reactions that can break bonds in proteins and other important molecules.
- An example of this would be when a gamma ray passes through a cell, the water molecules near the DNA might be ionized and the ions might react with the DNA causing it to break.
- They can also cause chemical changes by breaking the chemical bonds, which can damage living tissues.
- Short range effects include burns, impaired metabolism, dead tissues and death of the organisms.
- Long range effects are mutations increased incidence of tumors and cancer, shortening of life-span and developmental changes.
Non-ionising radiations affect only those components which absorb them and have low penetrability.
Ionising radiations have high penetration power and cause breakage of macro molecules.
- The biological damage resulting from ionizing radiations is generally termed as radiation damage.
- Large amounts of radiation can kill cells that can dramatically affect the exposed organism as well as possibly its offspring.
- Affected cells can mutate and result in cancer. A large enough dose of radiation can kill the organism.
- Radiation damage can be divided into two types: (a) somatic damage (also called radiation sickness) and (b) genetic damage.
- Somatic damage refers to damage to cells that are not associated with reproduction.
- Effects of somatic radiation damage include reddening of the skin, loss of hair, ulceration, fibrosis of the lungs, the formation of holes in tissue, a reduction of white blood cells, and the induction of cataract in the eyes. This damage can also result in cancer and death.
- Genetic damage refers to damage to cells associated with reproduction. This damage can subsequently cause genetic damage from gene mutation resulting in abnormalities. Genetic damages are passed on to next generation.
- The biological damage caused by the radiation is determined by the intensity of radiation and duration of the exposure.
- It depends on the amount of energy deposited by the radiation in the biological system.
- For example, alpha particles (protons) do much more damage per unit energy deposited than do beta particles (electrons).
- A traditional unit of human-equivalent dose is the rem, which stands for radiation equivalent in man.
- At low doses, such as what we receive every day from background radiation (<1 m rem), the cells repair the damage rapidly.
- At higher doses (up to 100 rem), the cells might not be able to repair the damage, and the cells may either be changed permanently or die.
- Cells changed permanently may go on to produce abnormal cells when they divide and may become cancerous.
- At even higher doses, the cells cannot be replaced fast enough and tissues fail to function. An example of this would be “radiation sickness.” This is a condition that results after high doses is given to the whole body (>100 rem).
- Alpha particles, can be blocked by a piece of paper and human skin.
- Beta particles can penetrate through skin, while can be blocked by some pieces of glass and metal.
- Gamma rays can penetrate easily to human skin and damage cells on its way through, reaching far, and can only be blocked by a very thick, strong, massive piece of concrete.
- Each radioactive material has a constant decay rate. Half-life is the time needed for half of its atoms to decay.
- Half-life of a radio nuclide refers to its period of radioactivity. The half-life may vary from a fraction of a second to thousands of years.
- The radio nuclides with long half-time are the chief source of environmental radioactive pollution.
- Nuclear fission in the reactor core produces lot of heat which if not controlled can lead to a meltdown of fuel rods in the reactor core.
- If a meltdown happens by accident, it will release large quantities of highly dangerous radioactive materials in the environment with disastrous consequences to the humans, animals and plants.
- To prevent this type of accidents and reactor blow up, the reactors are designed to have a number of safety features. Inspire of these safety measures three disasters in the nuclear power plants are noteworthy – Three Mile Island’ in Middletown (U.S.A.) in 1979, Chernobyl (U.S.S.R.) in 1986 and Fukushima Daiichi nuclear disaster in 2011.
- In the first two cases a series of mishaps and errors resulted in over heating of the reactor core and lot of radiation was released into the environment.
- The leakage from Three Mile Island reactor was apparently low and no one was injured immediately. However, in case of Chernobyl the leakage was very heavy causing death of some workers and radiation spread over large areas scattered all over Europe.
- The latest one – Fukushima Daiichi nuclear accident was triggered by an earthquake.
- Other important nuclear power plant disasters include Chalk river, Canada, Windscale Plutonium Production Center, U.K and Monju, Japan.
- Accidents with nuclear submarines and nuclear warships is a possibility.
- Radioactive wastes are of two types
- low level radioactive wastes (LLW) which include civilian applications of radionuclides in medicine, research and industry, materials from decommissioned reactors, protection clothing worn by persons working with radioactive materials or working in nuclear establishments.
- High level radioactive wastes (HLW) results from spent nuclear fuel rods and obsolete nuclear weapons.
Some proposed methods of disposing nuclear waste are:
- bury it deep underground in insulated containers. This is a strategy being pursued in United States.
- shoot it into the space or into the sun. The cost would be very high and a launch accident should be disastrous.
- bury it under the ice sheet of Antarctica or Greenland ice cap. The ice could be destabilized by heat from the waste. The method has been prohibited by international law.
- dump it into deep oceans by keeping the waste into glass and steel cases. But the containers might leak and contaminate the ocean.
- change it into harmless or less harmful isotopes. Currently no method is known to do that and the method would be too costly.
- presently waste fuel rods are being stored in special storage ponds at reactor sites or sent to reprocessing plants. Even though reprocessing is more expensive but some countries use reprocessing as an alternative to waste storage.
- Prevention is the best control measure as there is no cure available for radiation damage.
- All safety measures should be strictly enforced. UN should have more powers to perform safety checks in various nuclear establishments across the world.
- Worldwide monitoring of radiation leakage should be a priority.
- Proper technologies should be developed to prevent contamination of water and soil by radioactive waste and radioactive materials.
- More avenues for safe disposal of radioactive must be worked out.
- Regular monitoring through frequent sampling and quantitative analysis in domestic nuclear establishments.
- Appropriate steps should be taken to protect from occupational exposure.
- Gradually decreasing the share of nuclear power is a necessity.
- World must unite to ban production and use of nuclear weapons.
- The radiation that comes from mobile tower radiation is non-ionizing radiation.
- Every antenna on cell phone tower radiates electro-magnetic radiation (power).
- One cell phone tower is being used by a number of operators, more the number of antennas more is the power intensity in the nearby area.
- The power level near towers is higher and reduces as we move away.
- EMR may cause cellular and psychological changes in human beings due to thermal effects that are generated due to absorption of microwave radiation.
- The exposure can lead to genetic defects, effects on reproduction and development, Central Nervous System behavior etc.
- EMR can also cause non thermal effects which are caused by radio frequency fields at levels too low to produce significant heating and are due to movement of calcium and other ions across cell membranes.
- Such exposure is known to be responsible for fatigue, nausea, irritability, headaches, loss of appetite and other psychological disorders.
- The current exposure safety standards are purely based on the thermal effects considering few evidences from exposure to non-thermal effects.
- The surface area of bird is relatively larger than their body weight in comparison to human body so they absorb more radiation.
- Also the fluid content in the body of the bird is less due to small body weight so it gets heated up very fast.
- Magnetic field from the towers disturbs birds’ navigation skills hence when birds are exposed to EMR they disorient and begin to fly in all directions.
- A large number of birds die each year from collisions with telecommunication masts.
- The MoEF has to notify the impacts of communication towers on wildlife and human health to the concerned agencies for regulating the norms for notification of standards for safe limit of EMR.
- Regular monitoring and auditing in urban localities/educational/hospital/industrial/ residential/recreational premises including the Protected Areas and ecologically sensitive areas.
- Carry out an ‘Ecological Impact Assessment’ before giving permission for construction of towers in wildlife and ecologically important areas.
- State Environment and Forest Department are entrusted with the task of providing regular awareness among the people about the norms on cell phone towers and dangers of EMR from them.
- Avoid overlapping of high radiation fields. New towers should not be permitted within a radius of one kilometer of the existing tower.
- The location and frequencies of cell phone towers and other towers emitting EMR should be made available in the public domain GIS mapping of all the cell phone towers to be maintained to monitor the population of bird and bees in and around the wildlife protected area and the mobile towers.
- Need to refine the Indian standard on safe limits of exposure to EMR, keeping in view the available literature on impacts on various life forms.
- To undertake Precautionary approaches to minimize the exposure levels and adopt stricter norms perennial, that live longer than agricultural crops.
- Any study conducted on impact of EMF radiation on wildlife needs to be shared to facilitate appropriate policy formulations.
- Soil pollution is defined as the ‘addition of substances to the soil, which adversely affect physical, chemical and biological properties of soil and reduces its productivity.
- It is build-up of persistent toxic compounds, chemicals, salts, radioactive materials, or disease causing agents in soil which have adverse effects on plant growth, human and animal health.
- They accumulate in soil and prevents germination of seeds. They stay in soil for centuries without decomposing (non-biodegradable).
- Burning of plastic in garbage dumps release highly toxic and poisonous gases like carbon monoxide, carbon dioxide, phosgene, dioxins and other poisonous chlorinated compounds.
- Toxic solid residue left after burning remains in soil. The harmful gases enters soils through chemical cycles.
- They includes fly ash, metallic residues, mercury, lead, copper, zinc, cadmium, cynides, thiocynates, chromates, acids, alkalies, organic substances, nuclear wastes
- Large number of industrial chemicals, dyes, acids, etc. find their way into the soil and are known to create many health hazards including cancer.
- Pesticides are chemicals that include insecticides, fungicides, algicides, rodenticides, weedicides sprayed in order to improve productivity of agriculture, forestry and horticulture.
- Chlorohydrocarbons (CHCs) like DDT, endosulfan, heptachlor accumulate in soil and cause biomagnification. Some of these pesticides like DDT and endosulfan are banned by most of the countries.
Fertilizers and manures
- Excessive use of chemical fertilizers reduces the population of soil borne organisms and the crumb structure of the soil, productivity of the soil and increases salt content of the soil.
- It includes concrete, asphalt, rungs, leather, cans, plastics, glass, discarded food, paper and carcasses.
- Radioactive elements from mining and nuclear power plants, find their way into water and then into the soil.
- Many air pollutants (acid rain) and water pollutants ultimately become part of the soil and the soil also receives some toxic chemicals during weathering of certain rocks.
- Reduced soil fertility due to increase in alkalinity, salinity or pH.
- Reduced crop yield due to reduced fertility.
- Reduced nitrogen fixation due to the reduced number of nitrogen fixers.
- Increased erosion due to loss of forests and other vegetation.
- Run off due to deforestation cause loss of soil and nutrients.
- Deposition of silt in tanks and reservoirs due to soil erosion.
- Health effects are similar to effects of water pollution.
- Ecological imbalance.
- Foul smell and release of gases.
- Waste management problems.
More or less same as for water pollution
- Indiscriminate disposal of solid waste should be avoided.
- To control soil pollution, it is essential to stop the use of plastic bags and instead use bags of degradable materials like paper and cloth.
- Sewage should be treated properly before using as fertilizer and as landfills.
- The organic matter from domestic, agricultural and other waste should be segregated and subjected to vermicomposting which generates useful manure as a byproduct.
- The industrial wastes prior to disposal should be properly treated for removing hazardous materials.
- Biomedical waste should be separately collected and incinerated in proper incinerators.
- Use of bio pesticides, bio fertilizers. Organic farming.
- Four R’s: Refuse, Reduce, Reuse, and Recycle.
- Afforestation and Reforestation.
- Solid waste treatment.
- Reduction of waste from construction areas.
- Noise by definition is “sound without value” or “any noise that is unwanted by the recipient”.
- Noise level is measured in terms of decibels (dB). An increase of about 10 dB is approximately double the increase in loudness.
- H.O. (World Health Organization) has prescribed optimum noise level as 45 dB by day and 35 dB by night. Anything above 80 dB is hazardous.
Effects of noise pollution
- Noise pollution leads to irritation, increased blood pressure, loss of temper, mental depression and annoyance, decrease in work efficiency, loss of hearing which may be first temporary but can become permanent in the noise stress continues.
- Road traffic noise can be reduced by better designing and proper maintenance of vehicles.
- Noise abatement measures include creating noise mounds, noise attenuation walls and well maintained roads and smooth surfacing of roads.
- Retrofitting of locomotives, continuously welded rail track, use of electric locomotives or deployment of quieter rolling stock will reduce noises emanating from trains.
- Air traffic noise can be reduced by appropriate insulation and introduction of noise regulations for takeoff and landing of aircrafts at the airport.
- Industrial noises can be reduced by sound proofing equipment like generators and areas producing lot of noise.
- Power tools, very loud music and land movers, public functions using loudspeakers, etc. should not be permitted at night. Use of horns, alarms, refrigeration units, etc. is to be restricted. Use of fire crackers which are noisy and cause air pollution should be restricted.
- A green belt of trees is an efficient noise absorber.
- Noise Pollution (Control and Regulation) Rules, 2000 define ambient noise levels for various areas as follows:
Category of Area/Zone
Limits in dB(A) Leq
|Day Time||Night Time|
|6 a.m. to 10 p.m.||10 p.m to 6 a.m|
- The Government of India on Mar 2011 launched a Real time Ambient Noise Monitoring Network.
- Under this network, in phase-I, five Remote Noise Monitoring Terminals each have been installed in different noise zones in seven metros (Delhi, Hyderabad, Kolkata, Mumbai, Bangalore, Chennai and Lucknow).
- In Phase II another 35 monitoring stations will be installed in the same seven cities. Phase III will cover installing 90 stations in 18 other cities.
- Phase-III cities are Kanpur, Pune, Surat, Ahmedabad, Nagpur, Jaipur, Indore, Bhopal, Ludhiana, Guwahati, Dehradun, Thiruvananthpuram, Bhubaneswar, Patna, Gandhinagar, Ranchi, Amritsar and Raipur.
- Silence Zone is an area comprising not less than 100 metres around hospitals, educational institutions, courts, religious places or any other area declared as such by a competent authority.