Chemical safety: benzene

Responding is Ashley Easterwood, marketer, ION Science, The Woodlands, TX.

Benzene is a hazardous, flammable chemical commonly found in many different aspects of the industrial sector, including the oil and gas and construction industries. It’s often used in the production of various plastics, resins and synthetic fibers. This makes it a common chemical in many manufacturing plants, as these materials are mass-produced.

Although benzene is useful in many aspects, it’s dangerous to humans in numerous ways. Many people are exposed to varying levels of benzene at work, which is why exposure to benzene is heavily regulated.

This chemical is extremely harmful to workers, and exposure limits are consistently being reevaluated to determine how much exposure is safe. Although OSHA’s official exposure limit for benzene is 1 part per million, last January the American Conference of Governmental Industrial Hygienists substantially lowered its advised Threshold Limit Value for the chemical to 0.02 ppm from 0.5.

In addition to this lower TLV, the 15-minute short-term exposure limit was eliminated. The SHEL is the period of time that a person can be consistently exposed to a hazardous material without suffering a significant increase in adverse effects. With the elimination of this limit, the recommended TLV of 0.02 ppm is now throughout an 8-hour workday. This significant reduction in exposure limits raises the questions: Why is benzene exposure so harmful, and why do regulations keep shifting?

Health effects

Benzene is a health threat to workers who are exposed to it in various ways, and symptoms of prolonged exposure can range from headaches and dizziness to more severe side effects. It’s dangerous to inhale its fumes, and it’s equally harmful when it contacts the skin.

Long-term exposure to benzene is known to the Department of Health and Human Services to cause cancer such as leukemia. This is why worker exposure limits are of the utmost importance. Limiting interactions with this harmful chemical is necessary to avoid long-term adverse health effects.

How to protect workers from exposure

Limiting the period of exposure to benzene is the most effective method of protection, but other steps can be taken to decrease exposure.

Portable gas-detection instruments are an effective tool for detecting benzene and monitoring exposure, as they allow workers to constantly monitor their exposure levels. These instruments often monitor time-weighted averages for benzene and additional hazardous total aromatic compounds.

Additionally, fixed gas monitors are equally useful for detecting benzene exposure limits.

All in all, benzene is useful in many different aspects, but exposure limits are consistently decreasing because of the chemical’s harmful health effects. With proper personal protective equipment and knowledge of exposure limits, adverse health effects can be avoided and benzene can be a useful chemical in the manufacturing process.

Editor's note: This article represents the independent views of the author and should not be considered a National Safety Council endorsement.