After considering the findings of a review of breast cancer (and heart disease) risks linked to shiftwork, UK government’s Industrial Injuries Advisory Council (IIAC) “found that most studies did not show a doubling of risk, an important criterion for prescription of a disease under the industrial injuries scheme. They were therefore unable to recommend adding breast cancer and ischaemic heart disease following a long history of shift working to the list of prescribed diseases for which people can claim Industrial Injuries Disablement Benefit.” The rules have been criticised for setting too high a qualification barrier for state compensation for occupational cancers. Many known workplace cancers, particularly those also common in the general population, could kill hundreds and possibly thousands each year and still not meet the doubling of risk requirement. In 2003, a report for the Health and Safety Executive (HSE) concluded there was ‘appreciable’ evidence of a link between breast cancer and shiftwork. Since then HSE has accepted shiftwork is a major contributor to the UK’s occupational cancer toll. In 2012, HSE research concluded that occupational breast cancer was responsible for several hundred deaths a year in the Great Britain. The paper noted: “The estimated total attributable fraction (female only) for cancer of the breast attributable to occupation overall and associated with shift work (including flight personnel) is 4.56% (95%Confidence Interval (CI)=3.26-5.97), which equates to 555 (95%CI= 397-727) attributable deaths and 1,969 (95%CI=1,407-2,579) attributable registrations.”

The association between shift working and (i) breast cancer (ii) ischaemic heart disease,  IIAC position paper 25, 8 December 2009.
The burden of occupational cancer in Great Britain – Breast cancer, RR852, 2012.