Chlorobenzene enters the environment from industrial and municipal discharges. Another potential source is the formation and emission of chlorobenzene as a product of incomplete combustion in waste incinerators. Occupational exposure occurs primarily through breathing the chemical. Personnel engaged in the production and handling of chlorobenzene would be at greatest risk. Chlorobenzene is slightly persistent in water, with a half-life of between 2 to 20 days.
Chlorobenzene is a flammable liquid and a fire hazard.
It is unreactive towards water and decomposes only at high temperatures. When heated to decomposition this compound emits toxic fumes of hydrogen chloride gas, CO and CO2. These exposures are most likely to occur in the workplace or in the vicinity of hazardous waste sites. Exposure to chlorobenzene occurs most commonly through inhalation and skin contact. It is readily absorbed through the lungs and gastrointestinal tract and likely to be absorbed through skin because of its lipophilic characteristic.