Benzene Toxicity - Health Effects and Management

Introduction

Benzene is a colorless chemical liquid that is used for the production of various complex industrial chemicals. Exposure to benzene causes severe adverse effects in humans. They are considered potential carcinogens. Benzene is released into the atmosphere from natural sources like volcanic eruptions and wildfires. Ingestion and dermal contact of benzene occur in industrial workers dealing with the manufacturing of synthetic fibers, medications, lubricants, rubbers, pesticides, and dyes. After reaching the human body through various sources, benzene results in toxic health effects. In cases of long-term exposure, it may lead to leukemia, aplastic anemia, and multiple myeloma.

What Is Benzene?

Benzene is a colorless or light yellowish liquid chemical that is primarily used as a solvent in the pharmaceutical and chemical industry. In addition, they are used as raw materials for the industrial production of various substances. Benzene is produced from both natural and man-made processes. Natural sources of benzene include forest fires and volcanic eruptions. Benzene is a natural component of gasoline, crude oil, and cigarette smoke. Industrial production of products like resins, plastics, synthetic fibers, rubbers, nylon, lubricants, detergents, and pesticides use benzene as raw material, resulting in occupational exposure to workers. Several studies have shown that exposure to benzene through touch, inhalation, or swallowing causes serious adverse health effects in humans.

What Are the Uses of Benzene?

• As a solvent for the production of resins and rubber.

• Manufacturing paints.

• For the production of synthetic fibers.

• Used for manufacturing detergents and pesticides

• Production of certain drugs.

• Used as a motor fuel (benzol).

• Production of explosives.

• As a chemical in the printing industry.

• Used for the dry cleaning process of woolen clothes.

• Production of plastic products.

What Is Benzene Toxicity?

Exposure to enormous amounts of benzene causes benzene toxicity and adverse health effects. Primary exposure to benzene occurs through inhalation of contaminated air that contains chemicals. Industrial workers are exposed to higher levels of benzene during the manufacturing of benzene or other chemicals made from benzene. However, people are exposed to benzene through contaminated air from factories, automobile exhaust, cigarette smoke, industrial wastewater, and gasoline fumes. From all these sources, benzene may reach the human body and induce toxic effects. After reaching the body cells, they are transformed into toxic intermediates, which alter the functioning of red blood cells, white blood cells, and immune system cells. Because of these toxic health effects, strict laws have been implemented by the governing authorities to regulate the amount of benzene exposure in industrial workers. According to the United States occupational safety and health administration (OSHA), the maximum permissible exposure limit in the workplace is one part of benzene per million parts of air (1 ppm) during an eight-hour working period.

What Are the Causes of Benzene Toxicity?

Benzene toxicity occurs when people are exposed to larger levels of benzene. It may occur from various sources.

The common sources of benzene exposure are the following.

• Gasoline fumes.

• Emissions from factories.

• Contaminated wastewater from industries.

• Motor vehicle exhaust gas.

• Tobacco smoke.

• Gas stations.

• Paints.

• Oil-based solvents and liquids.

• Adhesives.

• Building materials.

What Are the Symptoms of Benzene Toxicity?

1. Central Nervous System Symptoms

• Weakness.

• Drowsiness.

• Headache.

• Tremors.

• Dizziness.

• Seizures.

• Nervousness.

• Unconsciousness.

• Euphoria.

• Staggering.

2. Gastrointestinal Symptoms

• Nausea.

• Loss of appetite.

• Abdominal pain.

• Stomach irritations.

• Vomiting.

3. Respiratory Symptoms

• Shallow breathing.

• Chest tightness.

• Breathing difficulties.

4. Cardiovascular Symptoms

• Rapid heartbeat.

• Shock.

• Irregular heartbeat.

• Cardiac arrest.

5. Dermal Symptoms

• Red dots on the skin.

• Pale skin.

6. Visual Symptoms

• Blurred vision.

• Eye irritations.

What Are the Health Effects Associated with Benzene Toxicity?

• Acute Exposure - Acute exposure to high concentrations of benzene results in immediate symptoms after exposure. Benzene primarily causes central nervous system toxicity and adverse effects. They induce initial anesthetic action on the brain cells, followed by depression, respiratory failure, and death in cases of continuous severe exposure. Acute benzene exposure induces dermal, gastrointestinal, and respiratory irritation. After reaching the human body through multiple sources, benzene is converted to toxic intermediates. They generate oxygen-free radicals and cause cell damage. Benzene can cause death in cases of severe acute exposure through its anesthetic properties and respiratory arrest.

• Chronic Exposure - Repeated exposure to higher concentrations of benzene (more than 200 parts per million) can result in severe adverse effects. Chronic exposure may cause persistent central nervous system effects, aplastic anemia, acute myelogenous leukemia, thrombocytopenia, and pancytopenia. One of the main health effects of long-term benzene exposure is carcinogenicity. Benzene is considered a known human carcinogen. Acute myelogenous leukemia is observed in people who are exposed to benzene for a long period of time.

How to Manage Benzene Toxicity?

The first and foremost measure to manage benzene toxicity is to remove the affected individual from the benzene-exposed environment to prevent further exposure and serious complications. Benzene toxicity can be managed with proper emergency medical care. After admitting the patient, necessary emergency management to maintain proper airway, vitals, and respiration is done. Initial symptoms associated with benzene toxicity can be managed with specific medications. Central nervous system symptoms such as seizures can be managed with benzodiazepine drugs like Diazepam. In cases of severe respiratory failure, the airway can be managed with endotracheal intubation. There is no specific antidote treatment for benzene toxicity. The treatment consists of the management of symptoms with supportive measures.

Conclusion

Benzene is a chemical compound used in industries to manufacture multiple chemical products. A mild amount of benzene is always present in the outdoor and indoor air from natural sources. Exposure to elevated levels of benzene through inhalation, dermal contact, or swallowing may cause adverse health effects. In the initial stages of exposure, adverse health effects may involve respiratory, cardiovascular, nervous, gastrointestinal, and hepatic systems. Later on, long-term exposure results in severe conditions such as cancer and reproductive and developmental defects.