Nitrogen is present everywhere in Earth Systems. The atmosphere is comprised of 78% N2; Nitrates, Nitrites, and Ammonium is present in the soil; plants require nitrogen intake to grow, thus making nitrogen necessary for the health of entire ecosystems. However, despite Nitrogen's abundance in Earth Systems, too much or too little Nitrogen can cause health effects to humans and can alter ecosystems.
In Gupta et al's "Health issues related to N pollution in water and air," nitrates are ranked in order of pervasiveness of entry into human bodies as 1) drinking water 2) food and 3) air. Gupta et al list several sources where nitrates can enter into ground water, which via wells translates to drinking water. Sewage leakage, industrial pollution, and excessive nitrogen-heavy chemical fertilizers are the most prominent avenues for nitrates to enter into drinking water.
One health effect that consumption of nitrates in drinking water has is methemoglobinemia. Gupta explains that the nitrates in the water oxidizes the iron in haemoglobin. This causes blue baby syndrome, resulting from the lack of oxygen after the iron in the hemoglobin is oxidized.
Gupta et al further point that Nitrates act a "procarcinogen", meaning that nitrates can react with other chemicals to create carcinogens. Patients with cancer see an acceleration in cancer cell growth when they consume high levels of nitrate in their water.
Nitrates can enter the body via food in several different ways. Chemical fertilizers heavy in nitrates can leave the nitrate residue on the plants we eat. Gupta et al discuss how leafy vegetables tend to contrain high levels of nitrates resulting from over expression of a gene that produces nitrates in the plant. This nitrate accumulation in the plants can be compounded when eaten by animals that humans would consume, ie cattle.
Nitrous oxide is the air also, resulting from combustion of gasoline in the presence of the Nitrogen content in the air. Industrial processes can also pollute the air with too much nitrous oxide. Over exposure of nitrous oxide can cause tissue damage and swelling in the throat. Other respitory problems include pulmany oedema and asthman. Too little nitrous oxide in the atmosphere, however, cause respitory irritation and irritation in the eyes.
Gupta et al summarizes several other problems associated with consumption of high concentrations of nitrates. These include weakness in the infant, respitory infections, hypertenstion, gastrointesnal issues including diarrhea, still births, low birth weights, diabetes, birth sdefects, and thyroid problems.
Nitrates can other effects too, including ecosytem damage. Aber et. al. discuss nitrates and their effect on forests in "Nitrogen Saturation in Northern Forests Ecosystems: excess nitrogen from fossil fuel combustion many stress biosphere". Some main points Aber et. al. touch on are the effects of nitrous oxide in the air and the different negative effects that those gases create. One such negative effect is acid rain. The nitrous oxide has a great oxidizing potential and can easily react with water to form nitric acid. This acid rain has obvious effects: flora and fauna don't respond well to acid falling from the sky.
But, the acid rain has slightly less obvious effects. It can decrease the pH levels in rivers and lakes, creating an abiotic range outside that of the occupants of the water body. Further, nitrogen saturation can occur. Aber defines nitrogen saturation as amount of ammoniuma and nitrate concentration in excess of total plant demand. Aber finds that when nitrogen saturation is reached in a forest, some nitrogen is taken up though the plant and the plant itself becomes 'nitrogen saturated'. However, the majority of excess nirogen is leached out of the soil and runs off into a nearby stream.
When excessive nitrogen runs off into a stream, eutrophication occurs. Eutrophication is the process whereby algae seizes at the oppurtunity to ingest larger than normal quantities of nitrogen and/or phosphorous. The algae population in the water body grows untill either the quantities of nitrogen are used or seasonal changes reduces the population, or both. In either case, larger than normal amounts of algae die and sink to the bottom where bacteria, etc decompose them. When this happens, large amounts of dissolved oxygen are consumed and the water body becomes a "dead zone". In summary, nitrogen leaching into the water ways creates areas in water bodies without oxygen, prohibiting an ecosystem to live.
In summary, despite the importance of nitrogen to create and sustain biotic life and its abundance in nature, too much nitrogen intake can cause imbalances in ecosystems and the human body that result in health issues and ecosystem problems.
In Gupta et al's "Health issues related to N pollution in water and air," nitrates are ranked in order of pervasiveness of entry into human bodies as 1) drinking water 2) food and 3) air. Gupta et al list several sources where nitrates can enter into ground water, which via wells translates to drinking water. Sewage leakage, industrial pollution, and excessive nitrogen-heavy chemical fertilizers are the most prominent avenues for nitrates to enter into drinking water.
One health effect that consumption of nitrates in drinking water has is methemoglobinemia. Gupta explains that the nitrates in the water oxidizes the iron in haemoglobin. This causes blue baby syndrome, resulting from the lack of oxygen after the iron in the hemoglobin is oxidized.
Gupta et al further point that Nitrates act a "procarcinogen", meaning that nitrates can react with other chemicals to create carcinogens. Patients with cancer see an acceleration in cancer cell growth when they consume high levels of nitrate in their water.
Nitrates can enter the body via food in several different ways. Chemical fertilizers heavy in nitrates can leave the nitrate residue on the plants we eat. Gupta et al discuss how leafy vegetables tend to contrain high levels of nitrates resulting from over expression of a gene that produces nitrates in the plant. This nitrate accumulation in the plants can be compounded when eaten by animals that humans would consume, ie cattle.
Nitrous oxide is the air also, resulting from combustion of gasoline in the presence of the Nitrogen content in the air. Industrial processes can also pollute the air with too much nitrous oxide. Over exposure of nitrous oxide can cause tissue damage and swelling in the throat. Other respitory problems include pulmany oedema and asthman. Too little nitrous oxide in the atmosphere, however, cause respitory irritation and irritation in the eyes.
Gupta et al summarizes several other problems associated with consumption of high concentrations of nitrates. These include weakness in the infant, respitory infections, hypertenstion, gastrointesnal issues including diarrhea, still births, low birth weights, diabetes, birth sdefects, and thyroid problems.
Nitrates can other effects too, including ecosytem damage. Aber et. al. discuss nitrates and their effect on forests in "Nitrogen Saturation in Northern Forests Ecosystems: excess nitrogen from fossil fuel combustion many stress biosphere". Some main points Aber et. al. touch on are the effects of nitrous oxide in the air and the different negative effects that those gases create. One such negative effect is acid rain. The nitrous oxide has a great oxidizing potential and can easily react with water to form nitric acid. This acid rain has obvious effects: flora and fauna don't respond well to acid falling from the sky.
But, the acid rain has slightly less obvious effects. It can decrease the pH levels in rivers and lakes, creating an abiotic range outside that of the occupants of the water body. Further, nitrogen saturation can occur. Aber defines nitrogen saturation as amount of ammoniuma and nitrate concentration in excess of total plant demand. Aber finds that when nitrogen saturation is reached in a forest, some nitrogen is taken up though the plant and the plant itself becomes 'nitrogen saturated'. However, the majority of excess nirogen is leached out of the soil and runs off into a nearby stream.
When excessive nitrogen runs off into a stream, eutrophication occurs. Eutrophication is the process whereby algae seizes at the oppurtunity to ingest larger than normal quantities of nitrogen and/or phosphorous. The algae population in the water body grows untill either the quantities of nitrogen are used or seasonal changes reduces the population, or both. In either case, larger than normal amounts of algae die and sink to the bottom where bacteria, etc decompose them. When this happens, large amounts of dissolved oxygen are consumed and the water body becomes a "dead zone". In summary, nitrogen leaching into the water ways creates areas in water bodies without oxygen, prohibiting an ecosystem to live.
In summary, despite the importance of nitrogen to create and sustain biotic life and its abundance in nature, too much nitrogen intake can cause imbalances in ecosystems and the human body that result in health issues and ecosystem problems.
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