Main Industries and Occupations at Risk

  • Petrochemical industries, e.g., manufacture of benzene, production of carbon black;
  • Petroleum refineries;
  • Petrol retailers, e.g., oil terminals (loading and unloading), service stations, airport terminal workers (aviation gasoline);
  • Manufacture of some types of plastics, synthetic fibres and nylon (cyclohexane), detergents, synthetic resins, butadiene rubber, styrene, phenol, lubricants, dyes and pesticide;
  • Laboratories, e.g., use of benzene in analytical techniques;
  • Work involving use of commercial solvents such as toluene and xylene (benzene may be   present as a contaminant);
  • Work involving handling of fuels containing benzene, e.g., vehicle workshops;
  • Bulk storage terminals loading, unloading, storage of petrol and related products, benzene etc;
  • Waste treatment plants handling benzene-containing waste material;
  • Sampling of waste water from plants handling benzene.

Medical Examinations


  • Any occupational exposure to benzene

Types of Tests and Frequency of Examinations

  • Pre-placement medical examination: within three months of employment
    • Clinical examination with particular emphasis on: 
      • i.  past, present, and anticipated future exposure to benzene;  
      • ii.  haematological and central nervous system disorder;
      • iii.  current usage of medication with potential hematotoxic side-effects
    • Tests: 
      • i.  Haemoglobin (Hb);  
      • ii.  Full blood count–total white blood cells, red blood cells and platelets (FBC); 
      • iii.  Peripheral blood film (PBF) to look for blast cells;
      • iv.  Urinary tt-muconic acid (ttma) or s-phenylmercapturic acid (spma) estimation in an end-of-the-shift urine sample taken mid-week (creatinine-corrected; inhalation of tobacco smoke and use of sorbitol increases background levels and this should be considered in the interpretation of the results).
    • Unfit for exposure to benzene: 
      • i.  History of myelodysplastic syndrome; 
      • ii.  Young persons under 18 years of age;  
      • iii.  Pregnant/nursing mothers;
      • iv.  Persons diagnosed with liver disease.
      • Note:  Persons with thalassaemia minor may work with benzene.



Pre-placement and 12-monthly periodic medical examination

1 Clinical examination with emphasis on past, future exposure to benzene; haematological and CNS disorder, concurrent use of medication with potential haematotoxic side effects $50
2 Haemoglobin $25
3 Full blood count – total wbc, RBC, platelets
4 Peripheral blood film to look for blast cells
5 Urinary tt-muconic acid (ttma) or s-phenymercapturic acid (spma) estimation in end of shift urine sample taken midweek (creatinine-corrected) $350