IARC: Night shift work and cancer - not just breast cancer!

The International Agency for Research on Cancer (IARC) has made the IARC Monograph Volume 124: Night Shift Work available online. This volume comprises a single monograph on night shift work. 

Night shift work was defined as work during the usual sleeping hours of the general population, and included transmeridian air travel. Disruption of normal physiological circadian rhythms is the most marked effect of night shift work. In health-care, manufacturing, transport, retail, and services sectors, night shift work is essential for ensuring that production and activities can continue 24 hours per day, 7 days per week.

The IARC Monographs Working Group classified night shift work as “probably carcinogenic to humans” (Group 2A), on the basis of limited evidence of cancer in humans (for cancers of the breast, prostate, colon, and rectum), sufficient evidence of cancer in experimental animals, and strong mechanistic evidence in experimental animals. The emphasis in the past has been on night shift work and breast cancer, so the expansion to cancers of the prostate, colon and rectum is new. 
The monograph can be downloaded in pdf format from this page on the IARC website.

Bad managers breed unsafe behaviours

Managers who fail to display confidence or are condescending toward staff when dealing with safety issues, are major barriers to encouraging safe behaviour at work, a joint Australian and Iranian study has found. The researchers explored workers’, supervisors’ and safety managers’ attitudes and perceptions of safety in a petrochemical company in Iran, in order to identify the factors that discourage safe work behaviours. The researchers’ motivation was the hazardous nature of the petrochemical industry,  in part because of the inherently dangerous nature of the work conducted, and the significant financial and social losses due to incidents. According to the researchers, the most common immediate cause of incidents and injuries is “unsafe worker behaviour”.  

They conducted individual face-to-face and semi-structured interviews with twenty participants to gain an in-depth understanding of factors acting as barriers to safe behaviour. The participants reported managers lacking confidence when dealing with safety hazards or issues, and safety officers lacking authority and experience, the researchers from Tarbiat Modares University and the University of Sydney say. Poor safety directions and monitoring inhibited safe behaviours, they found.

The main themes the researchers identified were: (i) poor direct safety management and supervision; (ii) unsafe workplace conditions; (iii) workers’ perceptions, skills and training; and (iv) broader organisational factors.
Read more: Azita Zahiri Harsini, et al: Factors associated with unsafe work behaviours in an Iranian petrochemical company: perspectives of workers, supervisors, and safety managers [Full article] BMC Public Health, published online July 2020, doi: 10.1186/s12889-020-09286-0. Source: OHSAlert

Editor's Note: The premise that "unsafe worker behaviour" is the cause of incidents is, in the view of many experts, and the union movement, extremely superficial. Factors such as those identified here, but also training, experience, supervision, equipment and maintenance and more contribute to how workers are able to do their work. 

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