Adverse Effects of N-Hexane Toxicity

Introduction:

A molecule called N-hexane is extracted from natural gas and crude oil. It is a colorless, flammable liquid with a relatively unpleasant smell that resembles gasoline. It readily evaporates in the air and barely dissolves in liquid. As N-hexane is easily evaporated, nearly everyone is exposed to trace amounts of the chemical in the air because gasoline includes N-hexane. N-hexane has been found in the air at a quantity of 2 ppb. However, N-hexane is completely absent from foods, drinking water, and even cooking oils processed with N-hexane-containing solvents. Although industrial employees are most commonly exposed to N-hexane in occupational contexts, mainly the ones who work under shoe and footwear assembly workers, laboratory technicians and carpenters have a higher incidence of exposure.

What Are the Uses of N-Hexane?

Crude oil is used to create the chemical N-hexane. Pure N-hexane is an odorless liquid with a weakly unpleasant taste. It can release explosive fumes and is extremely flammable. Most of the N-hexane used in industry is blended with substances referred to as solvents. The main application of N-hexane-containing solvents is the extraction of vegetable oils from crops like soybeans. N-hexane is an ingredient in several consumer goods, including rubber cement, quick-drying glues employed in various activities, and gasoline. It is also incorporated into several types of specialties like printing, textile, furniture, roofing, and shoe industries.

How Is N-Hexane Exposed to the Environment?

When N-hexane is exposed to the environment, it evaporates quickly into the air, where it gets decomposed and barely dissolves in water. Most N-hexane spilled within the water will rise to the surface and evaporate. However, the ground-spilled N-hexane will evaporate before it can get absorbed by the soil. Almost everyone is exposed to extremely modest amounts of N-hexane in the air because it is present in gasoline. Humans get exposed only by breathing the polluted air, which contains N-hexane. Using volatile products like N-hexane-containing goods at home without appropriate ventilation may lead to exposure to such substances.

What Is the Mechanism of N-Hexane Toxicity?

A physiologically based pharmacokinetic model for rats was used to evaluate the part that kinetics play in the acute inhalation toxicity of N-hexane. The compartments of the model included:

• Localized fat tissue.
• Lumped compartment representing all slowly perfused tissues except fat tissue.
• Liver tissue.
• Lumped compartment representing all rapidly perfused tissues except liver and brain tissue.
• Brain (central nervous system) tissue.

Aqueous and lipid brain components were represented by two CNS (central nervous system) subcompartments. The inhalation of toxic substances may lead to death in mammals, including humans.

What Are the Adverse Effects of N-Hexane?

The adverse effects are broadly distinguished into four types:

• Acute Exposure Effects: It is also called the short-term effect, which affects the health of an individual with immediate exposure to N-hexane.

1. Direct contact with the substance may lead to inflammation of the eyes and skin, manifested by a burning sensation.
2. Inhalation of substances results in irritation of the nostril, throat, and lungs, which leads to cough, wheezing, and inability to breathe or breathlessness.
3. Other manifestations are headaches, nausea, vomiting, and dizziness. It rarely ends with coma and death.

• Chronic Exposure Effects: It is also called the long-term effect, which affects the health of an individual after long-term exposure to N-hexane and may last for even months or years. Large volumes of breathing lead to numbness in the hands and feet, followed by muscle weakness in the lower legs and feet. It might result in paralysis of the arms and legs due to continued exposure. However, they recovered in six to twelve months if they were taken out of the exposure.
• Cancerous Effects: Based on an animal study which was conducted by the New Jersey department of health, there is no significant sign of cancer due to exposure to N-hexane.
• Reproductive Effects: A study shows that N-hexane has major effects on the male reproductive gland or testes.
• Other Effects: Long-term exposure to the substance develops skin rashes and inflammation with dryness and redness. Additionally, it also affects the nervous system resulting in numbness, blurred vision, and muscular weakness in both hands and feet.

How to Diagnose N-Hexane Toxicity?

The N-hexane toxicity is diagnosed by appropriate neurological examination with past and present symptoms along with occupational history. The odor threshold level ranges from 65 to 248 ppm. When the threshold exceeds the normal range, it results in toxicity.

Urine Test: After exposure to N-hexane in large amounts for two to three days, urine is likely to have n-hexane breakdown products. Hence, it can be diagnosed by urine analysis.

What Are the Procedures to Be Followed After Accidental Exposure to N-Hexane?

Immediate first aid involves the following:

• When a Substance Comes Into Contact With the Eye: It is advised to lift upper and lower eyelids followed by flushing of the eye with water for at least about 15 minutes.
• When a Substance Comes Into Contact With the Skin: Appropriate washing with soap and water is considered to be major first aid to remove the substance spilled on the skin.
• When a Substance Comes Into Contact With Breathing: CPR (cardiopulmonary resuscitation) is advised in case of breathlessness followed by transferring the patient to medical care.

What Are the Precautions to Be Followed to Reduce the Risk of N-Hexane Toxicity?

• Focus on educating the kids and teenagers about the risks of breathing N-hexane containing substances.
• It is advised to keep N-hexane-containing goods such as quick-drying glues and cement away from toddlers.
• When handling these products, keep the air flowing appropriately.
• Never store these chemicals at home in containers that kids could desire, such as old soft drink bottles.

Conclusion:

The Environmental Protection Agency (EPA) demands that spills or unintentional discharges of N-hexane weighing 5,000 pounds or greater be reported. The National Institute of Occupational Safety and Health (NIOSH) advises against exposure to workplace air that contains more than 50 parts per million (ppm). For N-hexane in working air, the Occupational Health and Safety Administration (OSHA) has established an acceptable exposure limit of 500 ppm. N-hexane is a highly toxic chemical that poses substantial risks to human health, primarily affecting the nervous system. Strict adherence to safety measures, improved awareness among workers, and regulatory oversight are crucial for minimizing exposure and protecting individuals from the adverse effects of N-hexane.