The facts on 1,3-Butadiene

According to the latest estimates, 27,600 workers in the EU are potentially exposed to 1,3-Butadiene (1,3-BD). Data from 1990-1993 indicated that approximately 31,600 workers were exposed. The exposure occurs mainly through inhalation. 1,3-BD has a harmonised classification as Carcinogenic category 1A (substances known to have a carcinogenic potential for humans based largely on human evidence) according to the CLP Regulation. The major carcinogenic effects are leukemia and lymphoma).

Where risks occur

1,3-Butadiene is used primarily in the production of synthetic rubbers (including styrene–butadiene rubber), thermoplastic resins, latex, and as a chemical intermediate (in the production of neoprene for automotive and industrial rubber goods, in the production of methylmethacrylate-butadiene-styrene polymer, which is used as a PVC reinforcing agent, and in the production of adiponitrile (a nylon precursor)).

The main occupational exposure occurs in 1,3-BD monomer production plants and in styrene-1,3-BD-based rubber/polymer plants. Professions at high risk of exposure include process technicians in unloading, in the tank farm, and in the purification, polymerization and reaction areas, laboratory technicians and maintenance technicians.

Furthermore, workers can be exposed to 1,3-BD from petroleum refinery product streams or smoke produced during electrosurgery.

More about the substance

1,3-BD is a colourless gas produced by steam-cracking of paraffinic hydrocarbons. Emissions of 1,3-BD to the environment also results from sources such as automobile exhaust, cigarette smoke, the smoke of wood fires, and the burning of rubber and plastics. 1,3-BD is not known to occur widely as a natural product.

Hazards that may occur

The highest potential for occupational exposure to 1,3-BD is via inhalation. Exposure through ingestion of food and drinking water is expected to be very low, if appropriate basic hygiene measures are taken. Acute exposures to 1,3-BD may cause drowsiness or dizziness. Chronic exposure to 1,3-BD is associated with an increased risk of hemato-lymphopoietic cancer (i.e. leukemia and/or lymphoma).

What you can do

Substitution should be considered in applications where feasible. If alternatives are not available or 1,3-BD may occur as by-product, perform regular exposure assessments so it is known when actions should be taken.

There are several ways to reduce exposure to 1,3-BD. The preferred approach is utilizing engineering controls such as local exhaust ventilation and process modification. If these measures are not sufficient other measures may be implemented, including requiring respiratory protection where ventilation is not feasible, requiring workers to shower and change into street clothes before leaving the plant, and issuing workers protective eyeglasses and splash shields as needed.

In addition, it is important to train workers on risks, safe work practices and on effective hygiene measures. Personal protective equipment (PPE) should only be used as a last resort, after introducing all possible technical and organizational solutions.

References: RAC, IARC, ATSDR, NFA, OSHA, COM