Chemical Burns Causes And Symptoms

Overview

Chemical burns can be very serious and very painful, leaving permanent effects like scars, and might even be life-threatening.¹ Most people have heard of the expression “chemical burn” but have only a vague idea of what it actually means: chemical burns are those caused by chemical products, with no need for a heat source to cause damage to the tissue; in some cases, the burn might be obvious when there’s a spill of a product over your clothes or unprotected skin, but sometimes it might be entirely covert if you don’t realise you’ve been in contact with a chemical.¹

The World Health Organization estimates that worldwide, 180.000 deaths are caused by burns annually.² It is, therefore, extremely important to understand how to react when you or a loved one are victims of a chemical burn. What do you do? What symptoms does it provoke? How can you prevent chemical burns from happening?

Causes

Chemical burns are caused by exposure to harsh and harmful chemicals.¹ The most common agents are:¹

• Acids: like sulfuric acid, nitric acid, hydrofluoric acid, hydrochloric acid, acetic acid, formic acid, phosphoric acid, phenols, and chloroacetic acid.¹ Products like drain cleaner, toilet bowl cleaner, bleach, and descalers are common acid sources in a household.³
• Bases (alkali): like sodium and potassium hydroxide, calcium hydroxide, sodium and calcium hypochlorite, ammonia, phosphates, silicated, sodium carbonate, and lithium hydride.¹ Common sources of alkaline products are drain cleaners, oven cleaners, and lye.³ Cement is also a source of alkaline burns.⁵
• Oxidants: like peroxides, chromates, and magnates; hydrogen peroxide is the most common example, being a bleaching agent and antiseptic in low concentrations.¹

Other agents have also been found to cause injuries: hair colouring agents and vesicants like mustard gas, for example, have been known to cause chemical burns.¹

Most of the time, chemical burns in adults are a result of workplace exposure: most of those affected by it are men between the ages of 20 and 60 years old who work in industrial settings.⁴ However, although more rarely, children are also at risk of suffering chemical injuries. In many households, cleaning products are easily accessible to children, causing accidental injuries.¹ The upper extremities, head and neck, and lower extremities are the sites most usually affected by burns.⁴

Each agent has its particularities on how it damages the tissue: alkaline agents usually cause liquefaction necrosis (death of cells), leading to irreversible damage in the tissue; this might also affect blood vessels at a local or even systemic level, creating life-threatening injuries.¹ Acid damage is usually milder because it causes a different type of necrosis, known as coagulation necrosis, and it is self-limited in the sense that absorption of the substance is limited, mitigating the damage.¹

Signs and symptoms

Symptoms of burns can often appear much later than the exposure. A study performed in the United Kingdom, analysing data from chemical burn victims, found that the majority of them presented to the hospital 36 hours after the initial exposure.⁵

Commonly presented symptoms include:

• Skin damage: bleaching or darkening of the skin, burning sensation, and tissue necrosis are common presentations; alkali burns tend to be worse than acid burns.⁶

• Ocular damage: it is an urgent injury that requires immediate attention.¹ Redness of the eye and burning pain can occur.⁶
• Gastrointestinal damage: this can happen if there is ingestion of the chemical - either accidental or self-inflicted; in these cases, burning of the oesophagus and stomach lining is a big concern.¹

• Systemic manifestations: if the burns affect over 30% of the body, there is a risk of systemic complications that can be life-threatening.⁶
  • Hypotension (low blood pressure)⁶
  • Tachycardia⁶
  • Respiratory distress⁶
  • Increase in metabolic rate⁶ 

Diagnosis and treatment

Physical evaluation by a physician to determine the extension of the lesions is recommended.¹ It is important that the patient knows what kind of chemical caused the injury: different products might require different approaches to treatment, influencing the prognosis as well.¹ Other exams might be necessary depending on the nature of the injury. 

Ingestion of chemicals

If there is ingestion of a chemical, an endoscopy is highly recommended to assess the full extent of the injury to the gut lining.¹ Moreover, more endoscopies might be performed after the initial burn to evaluate healing.¹In case of ingestion of batteries, an X-ray can be performed to identify the object, while a CT scan without contrast is helpful to identify perforation of the mediastinum - contrast is not advised if there is a suspicion of perforation¹. Batteries are alkaline and can leak caustic fluids, and early removal through endoscopy or surgery is urged to prevent it from leaking and causing burns¹. If not possible or not done in time, the patient should be monitored until it passes through the stool¹.

Eye injuries

Eye injuries are among the most serious and require immediate medical attention by an ophthalmologist: they can lead to blindness and loss of the entire eye if unnattended.¹

Skin exposure

For skin lesions, monitoring the site over the course of the weeks or even months that it takes to heal is necessary: this prevents infections like cellulitis.¹ Although not always necessary, surgeries to remove necrotic areas can be performed, and later on, a skin graft to patch the area.⁵

Blood tests

Blood work is sometimes necessary to diagnose systemic damage.¹ A complete blood count, electrolyte levels (like calcium and magnesium), lactic acid levels, and kidney and liver studies might help understand the full extent of the damage caused by the burn.¹ In case of hydrofluoric acid burns, for instance, it is necessary to assess the levels of calcium and magnesium to prevent fluoride toxicity.¹

First aid

First aid is extremely important in reducing damage and promoting greater chances of survival in extreme cases. Here are a few steps on how to deal with chemical burns:

• Identify the source of injury: it is essential to know what caused the damage, as different chemicals have different properties and should be treated in different manners. For example, dry lime contains calcium oxide and should be dry brushed off the surface before being washed, as the calcium oxide reacts with water, forming an alkali and worsening the injury.⁴ Improper care can lead to a poorer prognosis
• Remove clothes or shoes that have been contaminated by the chemical: in most cases, the chemical will continue to induce injury until it is removed completely.⁴ It is important to protect the eyes and hands while dealing with contaminated objects in order to not burn yourself
• Wash the area immediately with water or saline solution: with the exception of metals and phenols, irrigation of the area is always advised.⁴ If you are unsure of whether or not a chemical should be washed off, call the emergency services immediately. There is no need to use soap, detergent or other cleaning agents, as the interaction between chemicals can cause a worse reaction: wash the area multiple times with only water or saline solution. Don’t rub or let the water pool over the area to avoid spreading the chemical
• Seek immediate medical attention: a medical professional will know how to properly deal with an injury, and the sooner the patient seeks help, the better the prognosis
• Don’t induce vomit if there has been ingestion: vomiting can lead to aspiration and further damage to the oesophagus, trachea and mouth, exacerbating the damage.¹ It isn’t recommended to administer any medication that can induce vomit or neutralising agents like charcoal without medical advice¹

Prevention

As most chemical burns occur in a work setting, this highlights the importance of wearing proper personal protective equipment (PPE): lab coats, long sleeve tops and bottoms, closed shoes, gloves, protection goggles, and having your hair tied back or protected by a hair cap, are some examples of how you can protect yourself against chemical burns. The World Health Organization also suggests the implementation and compliance of rules and regulations regarding chemicals to be effective in preventing burns.²

You can also prevent chemical burns in your own household. Keeping cleaning products and other dangerous substances away from children in high cabinets, preferably locked, can prevent accidents from happening. It is also important to know what kind of chemicals are in the products you buy, and avoid mixing chemicals: this can cause a chemical reaction and produce gases that are harmful.⁷ Dealing with cleaning products should be done in a careful manner, as they can cause burns to the eyes, skin, and lungs.⁷ Here are a few examples of chemicals you should never mix:

• Ammonia and bleach when mixed, form chloramines, a group of highly toxic gases that can cause severe burns to the lungs⁷
• Hydrogen peroxide and vinegar form peracetic acid, which is corrosive and causes damage to the eyes, skin, and lungs⁷
• Bleach and products like oven cleaner or drain cleaner (that contain alkaline products like lye/sodium hydroxide) form chlorine gas, an extremely toxic gas that can cause burns on the eyes, nose, throat and lungs⁷

Summary

Chemical burns are those caused by chemical products, regardless of heat. They are caused by improper exposure to chemicals like acids (like bleach, sulfuric acid, nitric acid, hydrofluoric acid, and phenols), alkalis (lye, ammonia, phosphates, and cement), as well as oxidants (like peroxides). Once in contact with the skin, eyes, oral mucosa, and gut lining, these products cause necrosis (tissue death) and extensive, often irreparable damage to the area In case of burns that affect a larger surface area (over 30% of the body), systemic complications like low blood pressure, tachycardia, and increased metabolic rate can be fatal if left untreated. Once exposed to a chemical, it is important to identify it, remove debris and clothes that are contaminated, and wash the area thoroughly with water or saline solution only. It is of utmost importance to seek immediate medical attention, as these injuries can be severe: burns can result in loss of vision, scars, need for skin grafts, and even death. Preventing chemical burns in a workplace setting can be performed by wearing PPE and following rules and safety regulations, and in a household, keeping cleaning products away from children and not mixing them is just as important to prevent accidents.