What is Ammonia Toxicity?

Ammonia is a colorless gas that has a strong, unpleasant smell. It easily dissolves in water and turns into ammonium ions. It naturally occurs in the human body, mainly during the creation of amino acids. In addition, our gut bacteria also produce ammonia.

Despite being a natural by-product, ammonia is highly toxic. This is why our body quickly converts it into urea, a less harmful substance, in the liver. The kidneys then remove this urea from our body.

In a healthy adult, the amount of ammonia in the blood usually ranges from 15 to 45 micrograms per deciliter. But, too much ammonia can be harmful. If the amount of ammonia in the blood crosses the liver’s ability to remove it, it can lead to ammonia toxicity. This might happen if there’s too much ammonia production, as in the case with a rare genetic disorder called congenital hyperammonemia, or if the liver cannot remove enough of it, like in liver cirrhosis, a disease that damages the liver.

The following discussion is about how the human body may be exposed to ammonia from outside sources and how it could harm us. Human body may be exposed and be harmed by ammonia if one inhales ammonia gas or the vapors from liquid ammonia, consumes liquids that contain ammonia, or if the gas comes into direct contact with the skin or eyes.

What Causes Ammonia Toxicity?

Ammonia is one of the most commonly created chemicals in the U.S., and it’s mostly used in fertilizers or animal feed. People can be exposed to ammonia in several ways:

1. If there’s a gas leak at facilities where ammonia is made, stored, or transported, the people who work at these places might breathe in or come into skin contact with the ammonia.

2. When fertilizers that contain ammonia are used, the level of ammonia in the air can increase. This could put farmers who use these types of fertilizers at higher risk of breathing in ammonia.

Ammonia is also found in household and industrial cleaning products—usually between 5% and 25% of the product. This means people in these places, especially children, might ingest ammonia by accident or intentionally. If these cleaners spill, people could breathe in a significant amount of ammonia.

The process of manure decay also produces ammonia. This puts farmers who work in animal confinement areas at increased risk of breathing in ammonia.

Risk Factors and Frequency for Ammonia Toxicity

In 2017, the American Association of Poison Control Center’s National Poison Data System reported that there were 1846 instances of people being exposed to ammonia. Out of these, there were 15 serious incidents, but fortunately, no one died. The report also mentioned 1366 cases of exposure to glass cleaners containing ammonia and 489 cases of exposure to all-purpose cleaners containing ammonia, with no fatalities reported in either scenario.

Exposure to ammonia typically happens accidentally, especially when it comes to ingestion of ammonia-containing cleaners, which primarily occurs among children. However, about 9.2% of domestic ammonia exposure is deliberate, mainly among adults.

Signs and Symptoms of Ammonia Toxicity

If someone breathes in ammonia, they may experience runny nose, throat discomfort, chest tightness, cough, difficulty breathing, and eye irritation. Due to ammonia’s strong, pungent smell, people often recognize the odor and can escape from it, avoiding long term exposure. However, if a person is exposed for an extended period or to high levels of ammonia, they may develop severe skin burns.

If someone accidentally or intentionally swallows ammonia-based products, such as certain household cleaners, they may feel pain in their mouth, chest, or upper stomach area. They could also experience abdominal pain and other stomach-related symptoms if ammonia has caused a tear in an organ, although these symptoms may not appear until one to three days after ingestion.

After ensuring a patient’s ability to breathe and stable circulation, a doctor will carry out a physical examination to determine the extent of the exposure. This includes:

Assessing their consciousness level
Looking for signs of burns, ulcers, or swelling on the face, mouth, nose, ears, and throat
Examining their breathing, including the rate and quality, any struggles, excessive saliva, coughing, unusual breath sounds, or decreased airflow
Checking the skin for burns
Checking the eyes carefully for damage, as ammonia can harm the cornea, lens, and even cause a tear in the eyeball
Assessing any pain or signs of a torn organ in the upper stomach area

As symptoms can take time to appear, the doctor may need to repeat the abdominal examination over time.

Testing for Ammonia Toxicity

Currently, there are no reliable lab tests that can measure the overall damage caused by ammonia toxicity in the body. For those with normal liver function, any external exposure to ammonia does not necessarily correlate with the ammonia levels in the blood. So, unfortunately, knowing these ammonia levels doesn’t help much with diagnosis.

Nevertheless, if you were exposed to ammonia, your doctor might perform several routine investigations. These could include a complete blood count, measurement of blood urea nitrogen and creatinine, checks for the level of lactic acid in your blood, kidney function tests, serum electrolyte tests, prothrombin time (a test that measures how long it takes for your blood to clot), international normalized ratio (another type of blood clotting test), blood type and cross-matching, and urine output monitoring.

If the doctors suspect respiratory (breathing) injury from inhaling ammonia, they may perform several additional assessments. These could include monitoring how much oxygen is in your blood using an instrument that clips onto your finger (pulse oximetry), monitoring your heart, checking the levels of oxygen, carbon dioxide and other gases in your blood (serial blood gases), taking X-ray images of your chest, running tests to measure how well your lungs work (pulmonary function tests), performing bronchoscopy to check your airways (a procedure that involves inserting a thin tube with a camera down your throat), or carrying out a ventilation-perfusion scan (a type of lung imaging test).

In cases where swallowing ammonia is suspected, an abdominal series may be taken to rule out any possible perforation (tears) in the digestive tract. An early endoscopy (a procedure to look at the interior lining of the digestive tract) may be performed too, especially within 12 hours, for patients presenting signs like stridor (a high-pitched, wheezing sound), drooling, difficulty in swallowing, or significant mouth injuries. Even if there are no visible injuries in the mouth, early endoscopic evaluation may be needed for most of these patients because the absence of mouth injuries doesn’t really indicate that the esophagus (the pipe that connects your throat to your stomach) has not been injured.

In instances where ammonia exposure involves the eyes, the doctors may perform a slit-lamp examination with fluorescein staining (an eye test using a special orange dye and blue light to detect damage to the eye’s surface), tonometry (a test to measure the pressure inside your eyes), or a conjunctival pH measurement (a test to determine the acidity levels in the eye).

Treatment Options for Ammonia Toxicity

Exposure to toxic amounts of ammonia is more uncommonly experienced through external contact than ingestion or inhalation; however, it can still be a serious situation. The first step in treating someone who has been exposed to ammonia is to immediately remove them from the environment where the exposure took place and cleanse their skin and clothing of any lingering ammonia.

The next step is to make sure their airway, breathing, and blood circulation are stable and sufficient. Note that some signs that a person needs additional support in maintaining an open airway are changes in alertness, severe burns on the face or in the throat or airway, a hoarse voice or a high pitched sound when inhaling, and significant difficulties in breathing. If present, the person might require an advanced airway or breathing tube.

Pure oxygen is often provided to help with breathing and should be warmed and humidified for comfort. Doctors typically avoid giving large amounts of fluid in these cases to prevent fluid from flooding and injuring the lungs.

If there are any burns on the skin, they should be rinsed gently with lukewarm water for at least 15 minutes and then irrigated frequently over the following 24 hours. It is also important to let the skin breathe and release any ammonia naturally, so avoid applying any creams or dressings.

For potential eye injuries, rinse the eyes with lukewarm water for at least 30 minutes or until the acidity of the eye’s surface is normal. It’s important to have the eyes checked by an eye doctor as exposure to ammonia may lead to permanent eye damage.

If someone has accidentally swallowed ammonia, try to dilute it by providing water or milk to drink. Inducing vomiting should be avoided as ammonia will be corrosive again when it comes back up, potentially causing more damage. The person should not eat or drink anything else until a specialist (a gastroenterologist) can examine the internal layers of the gastrointestinal tract. A follow-up examination is sometimes needed weeks later to check for narrowing or constriction in the swallowing tube if the person has difficulty swallowing (dysphagia).

The use of corticosteroid medication, which can reduce inflammation, in the treatment of ammonia exposure is debated. It may be beneficial to calm down swelling or over-sensitive airways.

Most of the time a person exposed to ammonia would typically be observed in the emergency department for about 6 hours and can be sent home once it’s confirmed that they sustained no significant injury and they are able to eat and drink. However, extended observation or admission to the hospital may be necessary if the person has persistent symptoms, burns seen on internal examination, difficulties breathing, or any abnormalities detected in laboratory tests linked to the ammonia exposure.

When a person breathes in gases with high irritability and water solubility, it can cause similar reactions to inhaling ammonia. This means it mainly affects the upper part of the airways. Some examples of such gases are acrolein, ethylene oxide, formaldehyde, hydrogen chloride, and sulfur dioxide. If someone is exposed to these kinds of gases in high amounts, they might struggle to breathe. Therefore, other factors that can cause sudden, severe breathing difficulties, like severe asthma (status asthmaticus), serious allergic reactions (anaphylaxis), and choking on an object (foreign body aspiration) should also be considered.

Inhaling ammonia can also severely irritate the eyes. If a person suddenly begins to experience eye pain and irritation without an obvious cause, other eye conditions such as angle-closure glaucoma, having a foreign body stuck in the eye, and scratches on the surface of the eye (corneal abrasions) must also be considered.

If someone swallows ammonia, it has a similar effect to ingesting other harmful substances. Although management methods may be similar, determining the exact substance isn’t always necessary for immediate treatment. Likewise, skin exposed to ammonia might look like it has been exposed to a burn from a chemical or heat injury. These skin changes may resemble burns caused by substances such as sodium hydroxide, potassium hydroxide, and calcium hydroxide.

What to expect with Ammonia Toxicity

In 2017, there were no recorded deaths due to exposure to ammonia in the US. However, out of every 125 people who came in contact with this chemical, one experienced a major health problem. Mild exposure to ammonia is a condition that usually takes care of itself. The lack of symptoms within the first day of contact essentially means that no serious health issues will occur.

However, severe or long-lasting contacts with ammonia require hospital care and may even lead to death. Doctors have observed that the best way to predict serious long-term health issues or even death in patients who have inhaled ammonia is through physical examination of the chest when the patient initially comes in.

In patients who have come into contact with ammonia through their skin, the amount and depth of the burns indicate what their chances are for recovery. For those who have swallowed the chemical, the severity and depth of burns in the upper part of their digestive system, as seen through a scope, can predict their recovery and guide how their doctors will manage their treatment.

Possible Complications When Diagnosed with Ammonia Toxicity

Inhaling ammonia gas can harm the outer layers of lung tissue, which can make a person more susceptible to developing additional bacterial or fungal infections. Acute respiratory distress syndrome (ARDS) and acute lung injury (ALI) are also usual complications.

Frequent exposure to low to moderate levels of ammonia might result in the development of obstructive diseases that impacts the airway. Intense short-term exposure can harm the base layers of lung tissue, potentially leading to chronic lung disease that may even require a lung transplant.

Concerning ingestion injury, most patients (83.7%) do not develop any lasting complications. However, immediate complications can occur, such as inadvertent inhalation of stomach contents into the respiratory tract (aspiration), confusion, and rupture of an internal organ. Long-term complications may include the narrowing of the esophagus and frequent monitoring through endoscopy is typically suggested for these patients.

Summarized Side Effects:

Increased risk of bacterial or fungal infections in the lungs
Acute respiratory distress syndrome (ARDS)
Acute lung injury (ALI)
Development of obstructive airway disease for chronic inhalation of ammonia
Possibility of chronic lung disease or lung transplant for severe acute exposure
Inadvertent inhalation of stomach contents into the lungs (aspiration)
Confusion or altered mental state
Rupture of an internal organ
Long-term narrowing of the esophagus

Preventing Ammonia Toxicity

The Agency for Toxic Substances and Disease Registry (ATDSR), an organization that protects public health, has some advice for the public on how to avoid exposure to ammonia, a common ingredient in household cleaners and fertilizers:

* When using cleaners that have ammonia in them, make sure the room is well-ventilated, meaning there’s plenty of fresh air moving through.
* Don’t keep cleaners with ammonia in glass bottles because if the bottle breaks, there could be a strong and harmful release of ammonia.
* Always put on the right clothes and eye protection when you’re using cleaners with ammonia.
* Keep any cleaners that contain ammonia where children can’t reach them.
* Try not to visit farms where fertilizers that have ammonia in them have been recently used.
* Do not go into places where animals are kept without using the right safety gear.

The ATDSR also wants workers who use ammonia in farming to remember to always follow the safety rules that are listed on their equipment and to use safety gear, like gloves and masks, when they need to.