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Understanding the Effects of Chemical FertilizersWhat Is Fertilizer?Fertilizer is any substance used to add nutrients to the soil to promote soil fertility and increase plant growth. Notice how nothing in there mentions the actual soil health; that's because not all fertilizers are made the same and not all are healthy for the soil.Soil health relies on a balance of macronutrients and micronutrients, as well as microbial health. It's vastly more complicated then simply adding nitrogen, phosphorus and potassium (NPK) to the ground and calling it a day.Why doesn't this work?Because science doesn't always get it right. In the past scientists once thought food only consisted of macronutrients, but have since discovered micornutrients, antioxidants and so on. The same goes for soil health: scientists have focused almost exclusively on NPK since their "discovery" in the mid-1800s. It's this reductionist science that has us assuming we understand the chemisty of Nature and soil and thinking we can solve it with a quick application of chemical fertilizers.Unfortunately, as unsustainable farming and gardening practices continue our soil is stripped of its health and we depend on amendments even greater. This leads to some pretty negative effects of chemical fertilizers.Negative Effects of Chemical FertilizersThe biggest issue facing the use of chemical fertilizers is groundwater contamination. Nitorgen fertilizers break down into nitrates and travel easily through the soil. Because it is water-soluble and can remain in groundwater for decades, the addition of more nitrogen over the years has an accumulative effect.At the University of Wisconsin, Madison, they discovered the effects of chemical fertilizers are compounded when mixed with a single pesticide. They discovered altered immune, endocrine and nervous system functions in mice, as well as influence on childen's and fetus's developing neurological, endocrine and immune systems. These influences "portend change in ability to learn and in patterns of aggression."73One popular fertilizer, urea, produces ammonia emanation, contributes to acid rain, groundwater contamination and ozone depletion due to release of nitrous oxide by denitrification process. With it's increased use and projections of future use, this problem may increase several fold in the coming decades.105Groundwater contamination has been linked to gastric cancer, goitre, birth malformations, and hypertension107; testicular cancer108and stomach cancer.109Excessive air- and water-borne nitrogen from fertilizers may cause respiratory ailments, cardiac disease, and several cancers, as well as can "inhibit crop growth, increase allergenic pollen production, and potentially affect the dynamics of several vector-borne diseases, including West Nile virus, malaria, and cholera."110Perhaps one of the scariest effects of chemical fertilizers is something called methemoglobinemia. In infants it is alternatively known as Blue Baby Syndrome. The risk most often occurs when infants are given formula reconstituted with nitrate contaminated water. The condition causes a decrease in oxygen in the blood and results in a blue-grey skin color, causes lethargy and/or irritability and can lead to coma or death.111I've been unable to find whether the same risk exists for breastfeeding babies whose mothers drank contaminated water.Nitrogen groundwater contamination also contributes to marine "dead zones". The increase in the water-soluble nitrates creates an influx of plant-life, which eats up oxygen and starves out fish and crustaceans. This has an impact not only on the aquatic ecosystem, but on local societies who depend on food sourced from those areas.106And then there is the highly questionable use of raw sewer sludge as a fertilizer. Yes, you heard me right. In some countries, raw, uncomposted and untreated human waste is applied directly to crops and soil, a practice known as "night soil" since it's typically applied at night. The risk of disease is obvious and high112, 113and this practice should never be confused with "humanure", a long, highly involved process of decomposing human waste into a safe resource.What We Can Do About ItKnowing and understanding the effects of chemical fertilizers doesn't do us much good without action on our part. Knowing how to protect our health is what counts. If you're on well-water have your water tested regularly by a reputable lab. Support organic and sustainable agriculture. Know your farm and your farmer and understand their practices. Take part in safeguarding organic practices and standards. VisitOrganic Consumersfor details. Learn more aboutorganic fertilizerfor your own garden.Stay informed, get involved and make a difference in our health.How Do Fertilizers Affect the EnvironmentWe all know that fertilizers are used for proper and healthy growth of plants but are they really healthy? What exactly are fertilizers? Well, a fertilizer is a substance, be it synthetic or organic, which is added to the soil in order to increase the supply of essential nutrients that boost the growth of plants and vegetation in that soil. With the rapid increase in population globally, the demand of food and agricultural yield has been rising tremendously. This is the reason why statistics show that almost 40-60% of agricultural crops are grown with the use of different types of fertilizers. Not only this, more than 50% people feed on crops that are grown as a result of using synthetic fertilizers. On the other hand, there are organic fertilizers that consist of manures and animal wastes. The following section discusses how fertilizers are affecting the nature and environment around us.Harmful Effects of Fertilizers on the Nature and Environment

Mother nature has always taught us to balance out everything, and still continues to do so! If you eat a lot, your body naturally bloats up and tells you to exercise and come back to shape. When you exercise too much, your body tells you to slow down and relax. If there is rain, you also get the Sun, each and everything works fine till a balance is maintained. And we all know the consequences of imbalance. A classic example for the same would be the rise in global warming due to various reasons, including deforestation! Same is the case with fertilizers. The problem is that humans tend to use too much of fertilizers in the soil because they have to cater to the global demand of food. As mentioned already, more than half of the total yield production is out of synthetic or inorganic fertilizers which contains components like nitrogen, potassium, sulfur, calcium, magnesium, and so on. These chemicals and minerals, although help in boosting the growth of plants, they also have their drastic side effects in the long run. Mentioned below are some key points defining the effects of using fertilizers on the environment. Have a look

Depletes the Quality of the SoilThough this may sound ironic to you, the fact is that using too much of fertilizers in the soil can alter the fertility of the soil by increasing the acid levels in the soil. Which is why it is recommended to get a soil test done at least once in every 3 years so that you can keep a track whether or not you are using the right amount of fertilizers. The levels of soil pH varies from 0-14, wherein 0 is considered to be the most acidic and 14 being the most basic. 7 is considered to be neutral. The ideal soil pH varies from plant to plant and can be altered by bringing in some changes. Bottom line for using too much of fertilizers in the soil is that, though it may seem to work currently, there are high chances that you may not use it for plant yielding in the long run.Alters the Biology of Water BodiesWhen you use too much of fertilizers in the soil, it leads to eutrophication. Fertilizers contain substances like nitrates and phosphates that are flooded into lakes and oceans through rains and sewage. These substances prove to become toxic for the aquatic life, thereby, increasing the excessive growth of algae in the water bodies and decreasing the levels of oxygen. This leads to a toxic environment and leads to death of fish and other aquatic fauna and flora. Indirectly, it contributes to an imbalance in the food chain as the different kinds of fishes in the water bodies tend to be the main food source of various birds and animals in the environment. You would be surprised to know that more than 50% of the lakes in the United States are eutrophic!

Affects on Human HealthThe nitrogen and other chemicals present in the fertilizers can also affect the ground waters and waters that are used for the purpose of drinking! One of the most common result for this can be the development of blue baby syndrome which occurs in infants whose skin tissues are low in oxygen, which is why their skin appears to be blue or purplish in color. You would also be interested to know that studies reveal that the use of lawn fertilizers and pesticides can cause health risks like cancer and chronic diseases in humans, especially in children.

Climate Changes Across the GlobeFertilizers consists of substances and chemicals like methane, carbon dioxide, ammonia, and nitrogen, the emission of which has contributed to a great extent in the quantity of greenhouse gases present in the environment. This in turn is leading to global warming and weather changes. In fact, nitrous oxide, which is a byproduct of nitrogen, is the third most significant greenhouse gas, after carbon dioxide and methane. Therefore, you can well imagine as to how harmful is the use of fertilizers for our environment and the ongoing use of fertilizers across the world will only make matters worse!These facts are alarming and a serious step needs to be taken as soon as possible to avoid more severe consequences. The use of fertilizers for growth and cultivation is keeping our stomach filled for now, but then if things keep on progressing the way they are, it wont take long to see the times where there is lack of food, water, and health. So make sure that you use fertilizers in moderation, allow your soil to replenish its nutrients naturally by giving it a break from crop production and avoid using fertilizers during the rains. A small step can also make a big difference. Lets hope for a healthy and safe tomorrowChemical Fertilizers Destroying the EnvironmentA project to assess the world's ecosystems has found that the widespread useof fertilisers and the burning of fossil fuels will severely damage life inlakes and rivers around the globe.The Millennium Ecosystem Assessment, launched by the World Bank inWashington in 2001, examines how any disruption to the environment, whetherby human action or natural events, will harm human health, food productionand natural resources.Scientists have spent the past three years piecing together data fromthousands of studies. Their official report will be published early nextyear, but a first draft shows a number of alarming trends.A major concern is the increase in nitrogen emissions because of fertiliseruse and the burning of fossil fuels."In the past 100 years, emissions have risen from around 20m tonnes a yearto more than 150m tonnes a year," said Robert Watson, the project leader andthe World Bank's chief scientist. "We're emitting more than seven times morenitrogen and that is going to have incredible implications for ecologicalsystems."As an ingredient in fertiliser, nitrogen helps to feed some 2 billionpeople. But when it is washed from soils into water courses it can makerivers and lakes too rich in nutrients.As a result, algae and other life can grow out of control, eventuallystripping oxygen from the water which fish and other aquatic life need.Dead zones have already begun to appear, notably in the Gulf of Mexico,which is fed by nitrogen-rich water from the Mississippi river. "We arelooking at major effects in the US, Europe and south-east Asia," Dr Watsonsaid.As the world's population is estimated to grow to 9 billion in 40 years,food production is expected to become more intensive, requiring ever morenitrogen-rich fertiliser.Kenneth Cassman, an expert on environmental health at the University ofNebraska, said the efficiency of nitrogen use needed to be "massivelyimproved". "There are a number among us who think this is more importantthan carbon emissions, in terms of environmental impact," he said.In a separate part of the study, the scientists found that global warmingwould severely disrupt ecosystems, especially in the developing world, if itwas not kept in check. An increase of more than 2C (3.6F) would be enough toseverely degrade the availability of food, water and human health indeveloping countries.Dr Watson, who worked as a scientific adviser to the White House during theClinton administration, said that while the final report would describedifferent ways the problems might be dealt with, it was up to governmentsand private companies to collaborate."We can move in a direction where we destroy our natural heritage or we canmove in a direction where we improve both human wellbeing and maintain ournatural heritage," he said. "We've got choices and we have to decide whichfuture we want."Chemical Fertilizers, Health, Environment and Bio-FertilizersThe over-use of chemical fertilizers and pesticides in tandem with the Green Revolution of nineteen sixties and seventies (also known as the new seed-fertilizer-water technology) in the Indian context following two decades of their widespread application in the West, has hardened the soil, decreased its fertility, polluted air and water, and brought hazards to our health and environment. Ironically, despite the disastrous consequences of the Green Revolution in the northern parts of the country in recent years, the government seems to be in mood to spread the aftermath of this chemical-seed-fertilizer technology to other parts of the country. However, the hazards of chemical fertilizers on health and environment have been well established by studies carried out from time to time and they pose serious challenges to sustainable development. In this perspective moving towards bio-fertilizers and organic farming from a system of farming requiring high doses of chemical fertilizers and pesticides seems to be a viable alternative as the latter is observed to be friendly to health and environment.

Chemical Fertilizers and Environment

Chemical or synthetic fertilizers are basically salts by definition, and therefore, are expected to be harmful to agriculture in the long run. Yet they were promoted by their manufacturers under the misgiving that they would replenish the nutrients in the soil. Contrary to this, studies carried out from time to time have established that synthetic fertilizers tend to replenish only nitrogen, potassium, and phosphorous, while depleting other nutrients and minerals that are naturally found in fertile soil. Decrease in soil fertility also corroborated with continual use of chemical fertilizers and pesticides in the field as revealed in these studies.

Excessive use of phosphatic fertilizers cause hardening of the soil as phosphorous does not dissolve in water, while alkaline fertilizers like sodium-nitrate, basic slag develops alkalinity in soil reducing its fertility. Increasing use of chemical fertilizers also causes imbalance in quantity of specific nutrients in the soil adversely affecting, in turn, soil fertility and vegetation.

Soil fertility is also reduced due to pesticides applied to wipe out unwanted herbs in the field, insecticides meant to kill pests, and chemicals that have bio-cidal activity affecting rodents etc. Pesticides cause land degradation in various ways. They kill some useful species like the earth worms and micro-organisms that maintain the natural fertility of the soil by their activities. The bacteria or micro-organisms in the soil would normally break down organic matter into plant nutrients, and help convert nitrogen from the air into a plant-usable form. There are other useful soil bacteria such as "disease organisms" which keep cutworms, chinch bugs, grubs, and other parasites in check. Decline in the organic matter of the soil also results in hardening of the soil which, besides affecting vegetation also decreases infiltration and water retention capacity.

Besides, application of chemical fertilizers and pesticides causes contamination of the aqua system both directly and indirectly. For instance, nitrogen is toxic to fish and invertebrates. It is also toxic to humans. People who depend on rural wells for potable water have higher risk of exposure to conditions like Methemoglobinemia, and aka Blue Baby Syndrome which damages blood cells and is traced to high levels of nitrate concentration as ground water is contaminated. The herbicide atrazine, one of the most commonly used pesticides, is known to be a common water contaminant. Pesticides developed in recent years are found to be more toxic to water dwelling insects, planktons, crustaceans and fish. Even a low level of the herbicide atrazine, through contamination of streams, ponds and estuaries can be harmful to the whole aqua system. It may inhibit the growth of algae and plankton affecting the diet and reproduction of fish or other water bodies.

It has been observed that, chemical pesticides no more killed the target pests, for the latter had developed resistance absorbing the residue of such pesticides while they have hit the non-target pests, birds and micro-organisms beneficial to agriculture and environment. There are pesticides like organochlorine that are, though breakable, relatively faster than DDT, hit the non-target organisms. They enter the food chain of human-beings and remain accumulated in species like the eagle, falcon and kites. The recent decline in the eagle population is the cause of it. There are cases of decline in kite and vulture population in India due to use of pesticide of an US multinational corporation. It was banned only recently following protest by ecologists.

Again, use of pesticides not only pollutes the ecosystem contaminating the soil and acqua system, but also pollutes the air. For, even a careful spray of pesticides can make it mix in the air as vapour. As a result, there are chances of poisoning of bees and other pollinators. Thus, apart from posing a threat to biodiversity affecting flora and fauna, chemical fertilizers and pesticides destroy the environment through air, water and soil pollution.

Chemical Fertilizers, Bio-fertilizers and Our Health

Pesticides and overuse of chemical fertilizers also affect our health by retaining the residue by food chain. There are evidences of residues of pesticide in vegetables causing chronic health conditions in human-beings such as cancer and other systematic dysfunctions. Residues in food and water extend the hazards to a much wider population than that affecting the farmers alone.

A twelve-year study by researchers comparing organically grown and chemically grown foods found that synthetic nitrogen fertilizer leaves toxic nitrates in vegetables at least 16 times higher than that found in vegetables grown organically. Nitrates and residues of pesticides have oncogenic or cancer producing elements. The element omega-3 found in vegetables protects us from heart disease, cancer and Alzeimer's disease. But it is decreasing day by day in foods chemically grown. As is obvious, these diseases were not very common before the World War II when chemical fertilizers were not used.

Scientists have found that minerals containing in the food are crucial to our health. They keep us disease free. Mere vitamins and calories are not sufficient for our survival. But it has been established by studies that chemical fertilizers and pesticides destroy the essential minerals in crops and vegetables. In comparison to vegetables grown under organic system of cultivation these minerals are found much less in quantity in chemically grown vegetables. So it is argued that the foods coming from modern agricultural methods would only fill your stomach but you remain deficient in nutrition.

Again, studies carried out by researchers in the US and UK over last seventy years has come to the conclusion that organic fruits and vegetables contained 27 per cent more vitamin C than those chemically grown. Besides, they invariably contained more minerals and much less toxic nitrates.

Bio-Fertilizers and Bio-pesticides as Alternatives

Unlike the synthetic fertilizers, bio-fertilizers would have no obnoxious problems on our health and ecosystem. Bio-fertilizers include excreta of animals such as cow-dung, vermin-compost, dhanicha (green manure), organic wastes, crop residues, manure etc having biological or organic origin. Use of bio-fertilizers brings back the natural fertility of the soil without causing harm to earth-worms and micro-organisms. Besides, these fertilizers do not leave toxic residues in the food. Far from it, they would retain the natural minerals and the plant absorbs from the soil.

Bio-fertilizers like vermin-compost will increase soil fertility and prevent hardening of the soil. The vermin and living micro-organisms in the soil would also break the naturally available nitrogen from the air for plant use. Again, it will help allowing infiltration of rain water rather than causing water-logging. The use of bio-fertilizers will have little detrimental effect on ground water as there would be little nitrogen leaching into the earth contaminating the water.

Again, the use of animal and plant wastes in the field as manures will clean the environment. The organic wastes piled up everywhere can be used as compost reducing the environmental pollution. Besides, the deposits from ponds and aquatic systems can be used as bio-fertilizers and pesticides. This will clean the aquatic system while increasing productivity in the field.

As against the poisonous chemical pesticides bio-pesticides prepared from natural biological resources like plants and standardized microbes have no harmful effects. Local bio-pesticides like neem leaf and oil, karanj (derris indica) extracts and oil, cow urine can be used as insecticide and fungicide. Unlike the chemical pesticides they do not hit the non-target pests nor do they pollute the environment.

Preparations of neem include neem cakes, neem kernel, neem oil etc. Neem leaves and oil have been used by farmers in the Indian subcontinent since time immemorial as effective pesticide and preservative as well. Scientists in India, US and Europe have discovered many properties of neem as an obnoxious pest controller. Studies have shown that instead of killing pests at one go neem serves as a pest repellant and ovipositional deterrent, that is, pests do not spread eggs on plants applied with neem extracts.

Karanj oil and preparations made from it (now available with firms manufacturing them) serve as effective insecticide and miticide. All kinds of mites causing harm to plants like the red spider mites, scarlet mites, yellow mites etc are effectively controlled by preparations made from karanj.

Conclusion

The development of hybrid seeds of cereals, pulses and other crops though raised the productivity and supported the growing population of the country from starvation, since the sixties, it required greater use of chemical fertilizers, some of the compounds imported from developed countries. After two decades of the Green Revolution it was found that the soil was losing its fertility demanding more and more of chemical fertilizers for the high yielding varieties (HYV) of seeds to raise productivity, while pesticides were to be used in greater doses as pests developed greater resistance. Today the situation is so acute that productivity cannot be increased without surpassing the dangerous level of fertilizer use affecting health and environment, especially in regions like Haryana and Punjab where the per capita consumption of chemical fertilizers is very high. In view of the above hazardous effects of synthetic or chemical fertilizers and pesticides, the question arises, should we continue the use of HYV seed-chemical fertilizers technology? If not, what are the alternatives? In the present context, a system of organic farming using indigenous rather than HYV seeds with bio-fertilizers and local pesticides seems to be the only solution. It is time that both the Union and State Governments should arise from their slumber and promote and propagate the system of organic farming dismantelling the use of chemical fertilizers and pesticides.