Polycyclic Aromatic Hydrocarbon, Haematological and Oxidative Stress Levels in Commercial Photocopier Operators In Lagos, Nigeria

Ghana Med J. 2015 Mar;49(1):37-43. doi: 10.4314/gmj.v49i1.7.


Background: Human exposure to hazardous substances in the environment has been known to play an important role in the pathogenesis of some diseases. Photocopying machines have become a cheap source of self-employment in Nigeria. For obvious reasons the highest level of patronage is encountered in the campuses of educational institutions. However, the persons who operate the machines are always exposed to possible hazards associated with the job without protective devices.

Objective: This study investigated the levels of oxidative stress, polycyclic aromatic hydrocarbon (PAH) and haematological parameters in blood samples of photocopier operators.

Methods: The experimental procedure involved 50 consented subjects selected based on some criteria. The haematological parameters, oxidative stress and PAH levels were determined using standard methods.

Results: The results showed no significant difference (p ≥ 0.05) in the haematological parameters between the test subjects and the controls. However, there were duration on the job (yrs) dependent significant decrease in the level of superoxide dismutase (SOD) of the photocopier operators compared with the controls (> 5 years p≤ 0.0001; 4-5 years p≤0.001). The level of reduced glutathione (GSH) was significantly decreased across all lengths of duration on the job compared with the controls.

Conclusion: The findings in this study revealed increased level of oxidative stress in photocopier operators with no significant change in haematological parameters. The health implication of operating photocopiers call for quick health education and intervention tailored to monitoring and guiding the photocopier operators. This will help to prevent or manage continuous exposure to the hazards of photocopying machines.

Keywords: Nigeria; PAH; Photocopier operators; haematology; oxidative stress.

MeSH terms

  • Adolescent
  • Adult
  • Copying Processes*
  • Employment / statistics & numerical data*
  • Female
  • Glutathione / blood
  • Humans
  • Male
  • Middle Aged
  • Nigeria
  • Occupational Exposure / adverse effects
  • Occupational Exposure / analysis*
  • Oxidative Stress / physiology*
  • Polycyclic Aromatic Hydrocarbons / blood*
  • Superoxide Dismutase / blood
  • Time Factors
  • Young Adult


  • Polycyclic Aromatic Hydrocarbons
  • Superoxide Dismutase
  • Glutathione