Ammonia's Water Pollution: Understanding The Cause And Impact

Ammonia is a pollutant that is frequently found in aquatic ecosystems and is toxic to aquatic life. It is one of several forms of nitrogen that exist in aquatic environments. Ammonia causes direct toxic effects on aquatic life, including physical damage, altered behaviour, and even death. It also decreases the biodiversity of aquatic ecosystems. Ammonia in water primarily occurs due to agricultural fertilizers and industrial process wastes. Municipal waste treatment plants are designed to protect water bodies from excess inputs of pollutants such as ammonia, but during storms, excess flow may be diverted into combined sewer overflows that release untreated waste into water bodies.

Ammonia's toxicity to aquatic life depends on water temperature and pH

Ammonia is a common industrial chemical used in the synthesis of many nitrogen-containing organic and inorganic chemicals, as well as in fertilizers. It is a key component of the nitrogen cycle in streams, where it may dissolve in the water column or associate with sediments. It can enter aquatic environments through direct means, such as municipal effluent discharges and animal waste, and indirect means, such as nitrogen fixation, air deposition, and agricultural land runoff.

Ammonia is toxic to aquatic organisms at high enough concentrations. The relative contribution of unionized versus ionized forms to total ammonia concentrations depends on certain water quality criteria, most notably pH and temperature. As the pH increases, so does the proportion of ammonia in its unionized form, which is the most toxic to aquatic life.

The dynamic equilibrium between NH3 and NH4+ is affected by water temperature and pH. Warmer water will contain more toxic ammonia than cooler water. At a pH of six, the ratio of ammonia to ammonium is 1:3000, but this decreases to 1:30 when the pH rises to eight (becomes less acidic).

The EPA has published final national recommended water quality criteria for the protection of aquatic life from the toxic effects of ammonia in freshwater. The criteria reflect new data on sensitive freshwater mussels and snails and supersede the EPA's previously recommended 1999 ammonia criteria.

Municipal waste treatment plants can cause high ammonia releases into streams

Ammonia is one of the forms of nitrogen that exist in aquatic environments. Unlike other forms of nitrogen, ammonia can cause direct toxic effects on aquatic life. It is produced for commercial fertilizers and other industrial applications. Natural sources of ammonia include the decomposition of organic waste matter, gas exchange with the atmosphere, forest fires, animal and human waste, and nitrogen fixation processes.

Ammonia can enter the aquatic environment via direct means such as municipal effluent discharges and the excretion of nitrogenous wastes from animals. Municipal waste treatment plants and public-owned treatment works (POTWs) process domestic waste and are operated to comply with permit limits designed to protect receiving water bodies from excess inputs of pollutants such as ammonia. However, during storms, excess flow may be diverted into combined sewer overflows (CSOs) that deposit untreated municipal waste directly into streams and lakes. Treatment plant failures may also result in high ammonia releases into streams.

The US EPA has published final national recommended water quality criteria for the protection of aquatic life from the toxic effects of ammonia in freshwater. The EPA's 2013 ammonia criteria reflect new data on sensitive freshwater mussels and snails and incorporate scientific views on its draft 2009 criteria. The EPA has also published supporting information to assist states, territories, and authorized tribes in considering the adoption of the new recommended criteria into their water quality standards.

Ammonia releases into streams can have significant ecological effects. Ammonia is lethal to some sensitive freshwater fish and highly toxic to freshwater invertebrates. It can also cause fin erosion in trout and lethal and sublethal effects in mussels. Ammonia vapors are also toxic to livestock, and dairy, swine, and poultry producers operating near a release or potential release must be notified to take appropriate action.

Ammonia pollution decreases biodiversity in aquatic ecosystems

Ammonia (NH3) is a chemical compound of nitrogen and hydrogen that is produced for commercial fertilizers and other industrial applications. It is the second most synthesized chemical on Earth, contributing economic value to many sectors. However, with so many uses, industrial nitrogen fixation effectively doubles natural reactive nitrogen concentrations in the environment. This has led to excess fixed nitrogen driving the degradation of soils, water, and air; intensifying eutrophication, biodiversity loss, and climate change; and creating health risks for humans, wildlife, and fisheries.

Ammonia is toxic to aquatic life, and its presence in water can have detrimental effects on aquatic ecosystems, leading to increased fish deaths and decreased biodiversity. The dynamic equilibrium between toxic ammonia and non-toxic ammonium in water is influenced by temperature and pH (acidity). Warmer water with a higher pH will contain more toxic ammonia, making it more harmful to aquatic organisms.

The sources of ammonia pollution in aquatic ecosystems can be both direct and indirect. Direct sources include municipal effluent discharges and the excretion of nitrogenous wastes from animals. Indirect sources, on the other hand, include nitrogen fixation, air deposition, and runoff from agricultural lands. During storms or treatment plant failures, excess flow may be diverted into combined sewer overflows (CSOs), resulting in the release of untreated municipal waste containing ammonia directly into streams and lakes.

The presence of ammonia in aquatic ecosystems can lead to eutrophication, which is the overgrowth of algae due to increased nitrogen levels. This rapid increase in algae reduces the dissolved oxygen in the water, creating hypoxic conditions that are detrimental to other aquatic life, such as fish. Additionally, ammonia pollution can harm the symbiotic relationship between coral and bacteria, leading to coral bleaching and death, which further decreases biodiversity in the ocean.

The effects of ammonia pollution on aquatic ecosystems highlight the importance of managing and regulating ammonia emissions to mitigate its impact on biodiversity in these fragile environments.

Ammonia in water is primarily caused by agricultural fertilizers

Ammonia is a colourless gas that is soluble in water and is used as a plant nutrient in agricultural fertilizers. It is the foundation for the nitrogen (N) fertilizer industry, with roughly 80% of the annually produced ammonia used for fertilizer production. Ammonia binds with airborne nitrogen to create nitrogen fertilizers, which are essential for food production.

Ammonia in water, known as aqua ammonia, is a popular liquid fertilizer. It is often added to irrigation water and used in flooded soil conditions. When anhydrous ammonia is applied to the soil, it reacts with water to form ammonium, which attaches to clay and organic matter particles. This prevents it from leaching away. However, if there is an excess of fertilizer, it can negatively impact the soil, surface water, and groundwater due to the dispersion of minerals and nitrogen excess.

Aqua ammonia is highly toxic to aquatic life. Even at a concentration of 0.02 mg/L, unionized ammonia is lethal to some sensitive freshwater fish. It is also highly toxic to freshwater invertebrates. Ammonia can enter the aquatic environment through direct means such as municipal effluent discharges and the excretion of nitrogenous waste from animals. It can also enter through indirect means such as nitrogen fixation, air deposition, and runoff from agricultural lands.

The US EPA has published water quality criteria to protect aquatic life from the toxic effects of ammonia in freshwater. Environmental factors such as pH and temperature affect ammonia toxicity to aquatic animals. A higher temperature increases the ratio of toxic ammonia to non-toxic ammonium, and a higher pH decreases this ratio.

Ammonia can cause physical damage to fish, alter their behaviour, and even cause death

Ammonia is a colourless and odourless chemical that can be extremely harmful to fish. It is a common cause of fish death in new aquariums, especially when immediately stocked to full capacity. Even at a concentration of 0.02 mg/L, unionized ammonia is lethal to some sensitive freshwater fish. Ammonia is also highly toxic to freshwater invertebrates.

Ammonia poisoning happens when a fish tank's pH levels become elevated, disrupting the nitrogen cycle. In ideal water conditions, ammonia levels should be zero. However, tap water and the decomposition of organic matter inside the tank can contribute to elevated ammonia levels. The dynamic equilibrium between toxic ammonia (NH3) and non-toxic ammonium (NH4+) is affected by water temperature and pH (acidity). Warmer water will contain more toxic ammonia than cooler water. As the pH level rises, the ratio of ammonia to ammonium decreases, and the water becomes less acidic.

Ammonia can cause physical damage to fish, including gill damage and ammonia burns. The fish's gills will take on a red or lilac colour, making them look like they are bleeding. As the problem progresses, the fish's tissues will begin to deteriorate, evidenced by red streaks or bloody patches on their body and fins. In some cases, the fish may be found lying at the bottom of the tank with clamped fins, appearing listless. As the damage from ammonia poisoning continues, it will eventually cause damage to the brain, organs, and the central nervous system of the fish. The fish will start to hemorrhage, both internally and externally, and eventually die.

Ammonia can also alter fish behaviour. Initially, the fish might appear to be gasping for air at the surface of the water. They will lose their appetite, become lethargic, and have clamped fins. Fish exposed to low levels of ammonia over time are more susceptible to bacterial infections, have poor growth, and will not tolerate routine handling as well as they otherwise would.

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