This monocyclic aromatic hydrocarbon is important in the petrochemical industry as a reaction intermediate in the production of styrene, the precursor to polystyrene, a common plastic material.

Ethylbenzene is often found in other products, including pesticides, cellulose acetate, synthetic rubber, paints, and inks.

[citation needed] Small amounts of ethylbenzene are recovered from the mix of xylenes by superfractioning, an extension of the distillation process.

[5] In the 1980s a zeolite-based process using vapor phase alkylation offered a higher purity and yield.

This offers low benzene-to-ethylene ratios, reducing the size of the required equipment and lowering byproduct production.

This happened in a chemical reactor operated by Shell which overheated due to an exothermal runaway reaction between the metal oxide catalyst and ethylbenzene.

As of September 2007, the United States Environmental Protection Agency (EPA) determined that drinking water with a concentration of 30 parts per million (ppm) for one day or 3 ppm for ten days is not expected to have any adverse effect in children.

The U.S. Occupational Safety and Health Administration (OSHA) limits exposure to workers to an average 100 ppm for an 8-hour workday, a 40-hour workweek.

[5] When transporting ethylbenzene, it is classified as a flammable liquid in class 3, Packing Group II.