Benzene health issues: Why it should be monitored
Hazardous chemicals that pose a risk to human health are present in many raw materials such as oil. Normally these are safely transported and contained within process pipework and reaction vessels during normal plant operation. However, routine plant repair and maintenance (planned turnaround) or a fugitive release, due to faulty anges on valves for example, can potentially expose workers above the legal occupational exposure limit (OEL).
The EU-wide and US-OSHA 8 hour time weighted average (TWA) airborne exposure for benzene is currently set at 1 part per million (ppm), equivalent to a concentration of 3.25 mg/m3 which is well below what most people can detect despite its distinctive ‘aromatic’ smell i.e. between 2.5 and 5 ppm in air.
- myeloid leukaemia
- lymphocytic leukaemia
- non-Hodgkins lymphoma
- multiple myeloma
- aplastic anaemia
Individuals who have experienced benzene poisoning requiring treatment show a substantially increased risk of mortality from leukaemia.