Concerns over cancer risk from photocopiers come from three main areas: toner, light sources and electro-magnetic fields.
Carbon black is the main ingredient in copier toner. In 2010, the International Agency for Research on Cancer (IARC) concluded that there is inadequate evidence to conclude that carbon black is carcinogenic (cancer causing substance) to humans, but there is sufficient evidence to conclude that carbon black is carcinogenic to experimental animals. Consequently IARC classified carbon black as possibly carcinogenic to humans. IARC is a part of the World Health Organisation which convenes international expert working groups to evaluate the evidence of the carcinogenicity of specific exposures. Manufacturer instructions should be followed when changing toner. It is expected that there will be low public and occupational exposure to toners under proper use conditions. The construction of toner containers is such that inhalation and contact with skin and eyes is minimised. Once used in the copier, toner is fused to paper as a water insoluble polymer matrix, causing very low public and occupational exposure.
Most current photocopiers use a variety of light sources. As glass transmits ultraviolet rays, copiers with ultra-violet producing lights such as fluorescent, tungsten halogen or xenon flash will expose documents to a small amount of ultra-violet, but at very low levels. Always use photocopiers according to the manufacturers’ instructions. Keep the document cover closed at all times during photocopying to prevent light leakage or where possible, prevent light exposure by using the automatic document feeder during photocopying.
Electric and magnetic fields exist around all electrical equipment. Office workers are exposed to extremely low frequency magnetic fields when using equipment such as photocopying machines and computer screens. In 2002, IARC reviewed all available evidence on the relationship between extremely low frequency magnetic fields and cancer. The review concluded that there was inadequate evidence of extremely low frequency magnetic fields increasing cancer risk in adults. Based on this review IARC classified extremely low frequency magnetic fields as possibly carcinogenic to human. In 2007, the World Health Organisation (WHO) reviewed the evidence, focusing on studies published after the IARC review. The WHO concluded that the results of relevant research published since 2002 did not warrant a change in the classification of extremely low frequency magnetic fields as a possible human carcinogen.