EFFECTS OF ENVIRONMENTAL POLLUTIONThe pollution of the environment & its natural resources such as water, air or land with different pollutants is known as environmental pollution. The biggest & main harmful effect of pollution is on the environment as it breaks up the environment & also the different ecosystems present in it. Environmental pollution has adverse effects on both the humans & the other environmental living and non-living things.
Environmental pollution is a worldwide problem & it causes hazardous effects on humans & natural resources. Environmental pollution is defined as the state of contamination of different natural resources of the environment with the introduction of the poisonous chemicals & gases in the atmosphere of the earth which leads towards the destruction of natural resources of the environment such as land, air or water. The different pollutants which pollute the environment may be regarded as primary or secondary pollutants & the pollutants having short term or long term effects on the environment due to their vitality & nature of causing damage to the environment. It is the state of the buildup of toxic chemicals & poisonous gases in the breathing zone of the atmosphere of the earth which leads to many harmful disorders & discomforts to all the life species relying on natural resources of the environment. Environment pollution occurs in pollution of different forms of the environment such as land, water, air, noise, thermal, radioactive or light pollution. When the pollutants enter in the different zones of the environment, the species dependent on these natural resources would suffer & face difficulties in surviving. The environment is polluted when the different types of pollutants such as greenhouse gases, harmful heavy metals & harmful chemicals.
The pollutants cause the long term as well short-term changes in the environment which have very dangerous effects. Kinds of environmental pollution1. Water pollution2. Land or soil pollution.
Noise pollution5. Light pollution6. Thermal pollution7. Radioactive pollutionThe wide spreading pollution problem in the environment causes both the physical & biological effects which vary from mild to severe in the intensity of causing problems.
The different physical effects of pollution are such as the effects which are visible to us or direct physical damage to the environment & humans. For example the splitting of oil into the earth’s resources like land or water from the pipelines or oil ships which will produce deadliest of the effects on the aquatic ecosystems & the different ecosystems flourishing on the land masses.
Also, the emission of air pollutants in the atmosphere also produces physical effects on the earth’s atmosphere by producing the different diseases of lungs in humans by the taking of polluted air. The different biological effects can be seen in the human population & on the different food chain of animals. The pollution produces biological effects by the destruction of the natural balance of environment very seriously & in extreme cases also leads to the death of human & animal species. Biological effects will be produced on the environment by the use of pesticides, herbicides, synthetic fertilisers etc. For the crop production in the farm lands will lead to the determinant effects on the humans & other biological species of nature.
Pollution Presentation Pdf
The various effects of pollution are shown in the diagram below:The different harmful effects of environmental pollution on the different living or non-living things of earth are discussed in detail below: Environmental degradation:Pollution cause very dangerous & hazardous effects on the environment which depletes the natural balance of the environment. The environment is degraded due to the addition of pollutants in the natural resources of the environment such as air, water or soil. The different examples of environmental degradation are as:1. The emission of greenhouse gases by various means into the atmosphere will lead to the global warming & the depletion of natural ecosystems of earth.2.
Carbon dioxide emissions in the oceans leading to the acidification of water resources by the large concentrations of carbon dioxide in water.3. Biomagnifications: It is defined as the addition of several toxins like those of heavy metals in the food chains or trophic levels of different species of environment causing depletion of species.4. Sulphur dioxide & different nitrous oxides will lead to acid rain which decreases the pH value of soil making it difficult for crop production purposes.5. The formation of smoke & haze will reduce the sunlight received by the plants leading to the decrease in photosynthesis & the production of tropospheric ozone which damages the plants.6. The addition of heavy metals & oil splits in oceans will lead towards the pollution of land masses & water resources making them unsuitable for use.
Effects on human healthThe decrease in quality of air will lead to several respiratory problems like asthma or lung cancer, different cardiovascular diseases, chest pain, congestion, throat inflammation etc. In humans due to the ingestion of polluted air. The consumption of polluted water due to different contaminant addition will cause skin problems like skin cancer or rashes on the skin, water-related diseases such as diarrhoea, malaria, several fevers etc. Noise pollution in the environment will also lead to the production of different psychological effects on the humans & also on the environment. The effects of different gaseous pollutants on humans are shown below in table: PollutantHealth effects at very high levelsNitrogen DioxideThis gas irritate the airways of the lungs, increasing the symptoms of those suffering from lung diseases.Sulphur DioxideThis gas will irritate the airways of the lungs, increasing the symptoms of those suffering from lung diseases.OzoneThis gas will irritate the airways of the lungs, increasing the symptoms of those suffering from lung diseases.Carbon MonoxideThis gas prevents the uptake of oxygen by the blood. This can lead to a significant reduction in the supply of oxygen to the heart, particularly in people suffering from heart disease.ParticlesFine particles can be carried deep into the lungs where they can cause inflammation and a worsening of heart and lung diseasesOzone layer depletionIt is the emission of greenhouse gases in the environment leading towards the increase in their concentration in the atmosphere causing the global increase in earth’s temperature which has many hazardous effects on precipitation quantities & on other harmful effects. Global warming occurs due to the emission of several greenhouse gases like those of methane, sulphur dioxide, nitrous oxide, carbon monoxide, carbon oxide etc.
From the industrial infrastructure or from agricultural units by different means. The melting of ice caps or glaciers of the earth is also an effect of pollution as the rise in earth’s temperature will result in melting of ice.It is also an adverse effect of pollution. It occurs due to the emission of the CFCs in the environment from the use of different commercial & household products by humans which will destroys the ozone layer present in stratosphere leading to the entry of high wavelength UV rays directly on earth & resulting in many skin related diseases like skin irritation, skin cancers, allergies in humans & animals. Infertility of landThe increased use of herbicides, fertilisers, pesticides or synthetic manures for the performance of increased crop production will lead to the depletion of soil fertility due to the addition of harmful chemicals or heavy metals into the soil. Also, the addition of untreated sewage or industrial wastes directly or indirectly into the soil will also make it infertile for crop production or for the growth of vegetation.
Effects on animalsThe increased levels of pollution will also adversely affect the different animal species of the earth due to the depletion of the natural resources such as air, water or land units on which the wildlife depends fully for habitat & food. Also, the addition of toxicants into the food chain of animals will destroy them.
Effect on plantsThe increased level of pollution will have hazardous effects on the all kinds of vegetation present on the earth. The pollution of land will destroy the growth & development of plants as they will do not flourish on the land containing harmful heavy metals and chemicals. The roots of plants do not absorb the polluted water due to different contaminants added into water bodies supplying water to plants. Also, the leaves of plants do not prepare food in the polluted air of atmosphere due to less reception of sunlight. Effects on buildings or infrastructure formed by humansThe most important example of the effect of pollution on the human buildings is on one of the world heritage monument, the Taj Mahal in India which has a depletion of the wall sandstones due to polluted air around it. It also changes the colour of the monuments or buildings and damages them.
Eutrophication of water & land bodiesThe rain water will increase the addition of a nitrogenous pollutants concentration in the land & water resources which will lead to the algal growth on large scales causing depletion of naturally present nutrients in those resources which will cause harmful conditions for the growth of other species & organisms. Destruction of different ecosystemsThe pollution of atmosphere will also lead to the destruction of different ecosystems present in the environment like those of water bodies such as lakes, rivers, oceans, seas etc. Due to water pollution & of crop lands, wastelands, forest lands etc. Due to land or soil pollution. Depletion of earth’s atmosphereThe atmosphere of earth is depleted due to the presence of high quantities of polluted gases into the atmosphere by their large scale emissions from the industries & household sectors.
These large emissions will produce harmful effects on the atmosphere by the changes in gaseous concentrations of earth.
ADVERTISEMENTS:Tertiary level:This is at the national/country level. Each country has its own environmental protection agency to monitor pollution.Quaternary level:International/inter- Governmental bodies are closely associated with monitoring of pollution which is a global phenomenon. World Health Organization and United Nation Environmental Programme are actively involved. Biotechnological Methods for Measurement of Pollution:In recent years, environmental pollution detection and monitoring is being done by approaches involving bio-systems. For this, purpose, several groups of plants, animals and microorganisms are utilized. The environmental protection agencies (EPAs) consider bio-monitoring of pollution as a useful device to monitor environmental pollution from the point of diagnostic, preventive and remedial measures.
Criteria for Bio-monitoring of Pollution:The parameters or the criteria chosen for bio-monitoring of pollution are very crucial. They should be reliable, reproducible and cost-effective. Three types of criteria are mostly adopted for bio-monitoring of pollution-visual rating, genotoxicity rating and metabolic rating.Visual rating:In the visual rating, the growth rate and productivity are considered. When microorganisms are used in the test assay, the growth can be measured by turbidometric analysis. In case of higher plants, growth rate of different parts, visual damage to leaves, seed viability and germination frequency are taken into account.As regards animals (fishes are commonly used), the concept of LD 50 is used i.e. The dose at which 50% of the test organism is affected.
Sometimes, the presence or absence of a particular species of an organism serves as an indicator for the environmental pollution. ADVERTISEMENTS:Genotoxicity rating:Genotoxicity tests measure the extent of damage caused to an organism by environmental pollution at the cellular and sub-cellular levels. The genotoxic lesions may be detected on the cellular organelles (membranes commonly used), genomes, immune systems, biomolecules, etc.Cytotoxic tests such as measurement of chromosomal damage (including breakage), sister chromatid exchange (SCE) and micronuclei counting are also useful for pollution detection. The cell viability can be measured by detecting in vitro lysosomal viability.
In recent years, DNA probes are in use for the identification of disease- causing organisms in water.Metabolic rating. ADVERTISEMENTS:The biochemical changes with environmental pollution can be measured (qualitatively and quantitatively) in selected organisms. In fact, certain metabolic parameters can be used as biomarkers to assess the pollution stress.
The biomarkers used in metabolic rating include chlorophyll, proteins, nucleic acids (DNA and RNA) and changes in enzyme activities.The biotechnological methods adopted for pollution measurement are briefly described in the following order:1. General bioassays2.
Cell biological assays. Molecular biological assays4. Bioassays in Environmental Monitoring:In the early years, the conventional physical and chemical methods were used for the detection of environmental pollution. Bioassays are preferred these days, since the biological responses that reflect the damages to the living organisms are very crucial for the actual assessment of pollution.The organisms employed in the bioassays for pollution detection are expected to satisfy the following criteria.
It should readily take up the pollutant (absorption or adsorption).ii. The organism should be sensitive to the pollutant.iii. It should possess measurable features to detect pollution.iv. The organism should have wide occurrence, and available round the year.v.
The bioassay should be simple, reproducible and cost-effective.The most commonly used plants and animals in the bioassays are briefly described.Plant test systems in bioassays:Certain algae, bacteria, lichens, mosses and vascular macrophytes are commonly used in bioassays.Algal bioassays:Among the plant systems, algal bioassays are the most commonly used. Algae are considered to be reliable indicators of pollution due to their high sensitivity and easy availability, besides simple culturing techniques.
The criteria adopted for algal bioassays are the growth rate, biomass accumulation and photosynthetic efficiency.The algae used in the test assays include Chlorella, Microcystis, Spirulina, Navicula, Scenedesmus, Anabaena, Ulva, Codium, Fucus and Laminaria. In water, organic pollution can be detected by using the blue green algae, Microcystis, while metal pollution can be measured by Navicula.Bacterial bioassays:These are commonly used for the detection of fecal pollution in potable water, the most widely employed test being coliform test. Ames test that detects mutagenic pollutants is carried out by the bacterium Salmonella. Bacterial bioluminescence is a recent technique used for the measurement of gaseous pollutants and other compounds e.g. Sulfur dioxide, formaldehyde, ethyl acetate. Photo bacterium phosphoreum is the organism of choice for bacterial bioluminescence.Lichens in bioassays:Lichens are widely used for the detection of atmospheric gas pollution, particularly in cities.
Lichens are very sensitive for the measurement of sulfur dioxide.Mosses in bioassays:Environmental metal pollution can be detected by using certain forest and aquatic mosses e.g. Stereophyllum, Sphagnum, Brynus.Vascular macrophytes in bioassays:Water hyacinth (Eichormia crassipes) and duck weed (Lemna minor) are in use to detect aquatic metal pollution.
In fact, certain biochemical parameters of macrophytes are used to serve as biomarkers of pollution e.g., peroxidase activity increases due to metal pollution; inhibition of nitrate reductase activity by mercury. The other commonly used bioassay parameters are the estimation of soluble proteins, nucleic acids, chlorophyll, and assay of enzyme (e.g. Catalase, peroxidase) activities.Pollution-induced peptides in bioassays:Very recently, some workers have identified the presence of small peptides within the plant cells which are pollution-induced. These peptides, referred to as phytochelatins, are formed as a result of metal pollution.
They are reasonably reliable for the detection of metal pollution.Animal test systems in bioassays:Among the animals, certain fishes, protozoa and helminthes are employed in bioassays.Fishes in bioassays:Toxic effects of environmental pollutants on fishes have been in use for quite some time as a measure of bioassays. In fact, the concept of LD 50 (i.e.
The dose of the pollutant at which 50% of the test organisms are affected) has originated from the studies on fishes.The criteria or parameters used for assessment of fish bioassays include changes in the morphology and organs, behavioural pattern and modifications in metabolisms. The alterations in the enzyme acetylcholine esterase serve as a reliable marker for pesticide pollution. The most commonly used fishes in bioassays are Catla, Teleost, Labeo and Channa.Protozoa in bioassays:The ciliated protozoa serve as good bioassay systems for the detection of environmental pollution.
Pollution Ppt
The toxic effects of the pollutants can be measured by the changes in the behavioural patterns of protozoa, recorded on an ethogram.Helminths in bioassays:Rotifers are a group of helminths that grow on aquatic vegetation. They are used for the detection of organic matter in water (given by BOD). Rotifers, with round the year availability, easy cultivation, slow growth rate and easy recognition are used for bio-monitoring of water.Pollution-induced peptides in bioassays:As already described in case of plant bioassays (above), pollution-induced small peptides are found in animal cells also.
They are collectively referred to as metallothioneins (comparable to phytochelatins in plants). Metallothioneins are useful for the detection of metal pollution.Bio-monitoring of pollution with multiple species:Most often, bioassays using a single organism are not adequate to detect pollution. In such a case, multiple species of organisms are used. Cell Biology in Environmental Monitoring:Cell biology deals with the study of the structural and functional aspects of cells and the cellular organelles.
It is successfully exploited for environmental pollution detection, particularly with reference to mutagens and carcinogens.The cell biological methods primarily aim to trace the harmful effects of pollutants on different cellular components — membranes, chloroplasts, mitochondria, chromosomes. In addition, the macromolecules namely nucleic acids (particularly DNA) and proteins are also used. Further, cell biological methods help in understanding the mechanisms of toxicity of pollutants.Some important cell biological methods used in environmental pollution monitoring are described.Membrane damage in bioassay:The plasma membrane, an envelope surrounding the cell, protects the cell from hostile environment. It is the first cellular component to be directly exposed to pollutants. Many toxic substances that cause damage to cell structure and its functions are known. For the purpose of bioassay, the physical damages caused by pollutants or their deposition on the membranes can be detected by light, phase contrast and electron microscopy.This approach may not be always practicable. The alterations in the semipermeable properties of the membranes due to pollutants can be detected by leakage of enzymes (e.g., lactate dehydrogenase), efflux of electrolytes or uptake of trypan blue.
Water Pollution Ppt
Lysosomes are also useful as biomarkers for measurement of cell viability. This can be done by neutral red retention test.
The damaged lysosomes cannot retain this dye.In recent years, animal and plant tissue culture techniques are also used for pollution monitoring. This is made possible by measuring cellular damages observed in cell cycles. A good example is the use of human lymphocyte culture to monitor the persons exposed to toxic pollutants.Cytogenetic bioassays:The genetic damages of the cells, as reflected by changes in the chromosomes, can be effectively used in bio-monitoring of pollution. For this purpose, animals (e.g.
Insect Drosophila) and plants (e.g. Arabidiopsis) with shorter life cycles are preferred. Other plants such as pea, maize and soy bean are also used in cytogenetic bioassays.Chromosomal damage:The pollutants may cause several types of chromosomal damages- fragmentation, bridge formation, and disruption in cell division. The chromosomal alterations can be effectively used for pollution detection. It has been clearly established that the severity of chromosomal damage depends on the chemical nature of the pollutant.Micronucleus test:Severe damage to chromosomes by pollutants may result in large scale fragmentation of chromosomes, followed by micronuclei formation. The degree of micronuclei development is directly related to the severity of the damage. Micronucleus test (MNT) is used for screening of mutagenic compounds.Sister-chromatid exchange:The damages caused by pollutants results in misexchange of chromosomal segments (chromatids) during cell division.
The sister chromated exchange (SCE) can be detected by using a fluorescent dye technique.Ames test in bioassays:Ames test can be used for the detection of chemical mutagens and their carcinogenicity. This is very widely used bioassay for screening of various pollutants, drugs, cosmetics, food additives and metals. Ames test employs the use of a special mutant strain of bacterium namely Salmonella typhimurium (His –).
This organism cannot synthesize histidine, hence the same should be supplied in the medium for its growth.Addition of chemical carcinogens causes mutations (reverse mutation) restoring the ability of this bacterium to synthesize histidine (His +). By detecting the strain of Salmonella (His +) in the colony of agar plates, the chemical mutagens can be identified. The Ames assay can detect about 90% of the chemical carcinogens.Recently, the yeast cells (Saccharomyces cerevisae) are also used for the detection of chemical carcinogens. Molecular Biology in Environmental Monitoring:The use of molecular probes and immunoassays in monitoring of environmental pollution is gaining importance in recent years. Molecular biological bioassays are particularly useful for the detection of bacteria, viruses and other pathogenic organisms that cause diseases.DNA probes:DNA probes and polymerase chain reaction (PCR) can be effectively used for water quality monitoring, particularly potable water.
However, these techniques are expensive and not practicable at all places.Immunoassays:Immunological techniques are useful for the detection of pollutants (pesticides, herbicides) and identification of pathogens that exhibit immunological properties. Immunoassays are in use for the measurement of several pesticides e.g. Aldrin, triazines DDT, glyphosate.
Metabolic products of certain bacteria can also be detected by immunoassays. For instance, assay systems have been developed for the detection of toxins of cholera and Salmonella.In recent years, use of monoclonal antibodies (MAbs) in the detection and bio-monitoring of environmental pollution is gaining importance. In fact, assay techniques are available for detection of pesticide and herbicide contamination in water.Bioluminescent bioassays using Lux reporter genes:Certain genes, referred to as Lux reporter genes, on the plasmids produce assayable signals. Whenever these genes are expressed in luminescent bacteria like Photo bacterium and Vibrio. Some bacterial strains have been developed through gene cloning (employing Lux reporter genes) for the detection of pollutants and their degradation. For instance, genetically altered Pseudomonas can be used for detecting naphthalene, xylene, toluene and salicylate. Biosensors in Environmental Monitoring:A biosensor is an analytical device containing an immobilized biological material (enzyme, organelle, cell) which can specifically interact with an analyte (a compound whose concentration is to be determined) and produce physical, chemical or electrical signals that can be measured.
Biosensors are highly specific and accurate in their function. The details on biosensors—principles of working, types, various applications are described elsewhere Some of the important biosensors used in environmental pollution monitoring are briefly described.BOD biosensor:Biological oxygen demand (BOD 5) is a widely used test for the detection of organic pollution. This test requires five days of incubation.
A BOD biosensor using the yeast Trichosporon cutaneum with oxygen probe takes just 15 minutes for detecting organic pollution.Gas biosensors:Microbial biosensors for the detection of gases such as sulfur dioxide (SO 2), methane and carbon dioxide have been developed. Thiobacillus-based biosensor can detect the pollutant SO 2, while methane (CH 4) can be detected by immobilized Methalomonas.
For carbon dioxide monitoring, a particular strain of Pseudomonas is used.Immunoassay biosensors:Immunoelectrodes as biosensors are useful for the detection of low concentrations of pollutants. Pesticide specific antibodies can detect the presence of low concentrations of triazines, malathion and carbamates, by employing immunoassays.Other biosensors:Biosensors employing acetylcholine esterase (obtained from bovine RBC) can be used for the detection of organophosphorus compounds in water. In fact, portable pesticide monitors are commercially available in some developed countries. Biosensors for the detection of polychlorinated biphenyls (PCBs) and chlorinated hydrocarbons and certain other organic compounds have been developed.Phenol oxidase enzyme (obtained from potatoes and mushrooms) containing biosensor is used for the detection of phenol.
A graphite electrode with Cynobacterium and Synechococcus has been developed to measure the degree of electron transport inhibition during photosynthesis due to certain pollutants e.g. Herbicides.A selected list of environmental pollutants measured by employing biosensors is given in Table 54.1.