This volume of the IARC Monographs provides an evaluation of the carcinogenicity of night shift work, that is, work occurring during the regular sleeping hours of the general population. Globally, an estimated one out of five workers is engaged in regular night shift work, with percentages increasing over time in some countries. Night shift work is most common in the following industry sectors: transportation (for example, aircrew and truck drivers on long-haul trips), health care, manufacturing, and services (for example, social assistance, accommodation and food services, information and communications, travel and tourism).

An IARC Monographs Working Group reviewed studies of cancer in people exposed to night shift work (including transmeridian air travel), studies of cancer in experimental animals exposed to shifts in the light–dark schedule, and mechanistic evidence in both exposed humans and experimental systems. The review of the present Working Group was the first to be guided by the amended Preamble to the IARC Monographs, which was substantially updated in 2019.

Contents

• Note to the Reader
• List of Participants
• Preamble
• General Remarks
• 1. Exposure Data
  • 1.1. Identification of the agent
  • 1.2. Applications and drivers of night shift work
  • 1.3. Exposure characterization
  • 1.4. Regulations and guidelines
  • 1.5. Quality of exposure assessment in key epidemiological studies
  • References
• 2. Cancer in Humans
  • 2.1. Studies among night shift workers other than aircrew
  • 2.2. Studies among aircrew
  • 2.3. Meta-analyses of night shift workers, including aircrew
  • 2.4. Evidence synthesis for cancer in humans
  • References
• 3. Cancer in Experimental Animals
  • 3.1. Shifts in the light–dark schedule
  • 3.2. Shifts in the light–dark schedule with implant, transplant, graft, or modifying factors
  • 3.3. Extreme changes in photoperiod
  • 3.4. Extreme changes in photoperiod with modifying factors
  • 3.5. Extreme changes in photoperiod with implant, transplant, or graft
  • 3.6. Evidence synthesis for cancer in experimental animals
  • References
• 4. Mechanistic Evidence
  • 4.1. Evidence relevant to key characteristics of carcinogens
  • 4.2. Other relevant evidence
  • References
• 5. Summary of Data Reported
  • 5.1. Exposure characterization
  • 5.2. Cancer in humans
  • 5.3. Cancer in experimental animals
  • 5.4. Mechanistic evidence
• 6. Evaluation and Rationale
  • 6.1. Cancer in humans
  • 6.2. Cancer in experimental animals
  • 6.3. Mechanistic evidence
  • 6.4. Overall evaluation
  • 6.5. Rationale
• List of Abbreviations
• Annex 1. Supplementary Material for Section 1, Exposure Data
• Annex 2. Supplementary Material for Section 2, Cancer in Humans

This publication represents the views and expert opinions of an IARC Working Group on the Identification of Carcinogenic Hazards to Humans, which met in Lyon, 4–11 June 2019

Lyon, France - 2020

IARC MONOGRAPHS

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IARC Library Cataloguing in Publication Data

Names: IARC Working Group on the Identification of Carcinogenic Hazards to Humans.

Title: Night Shift Work.

Description: Lyon : International Agency for Research on Cancer, 2020. | Series: IARC monographs on the identification of carcinogenic hazards to humans, ISSN 1017-1606 ; v. 124. | “This publication represents the views and expert opinions of an IARC Working Group on the Identification of Carcinogenic Hazards to Humans, which met in Lyon, 4–11 June 2019.” | Includes bibliographical references.

Identifiers: ISBN 9789283201625 (pbk.) | ISBN 9789283201915 (ebook)

Subjects: MESH: Carcinogens. | Shift Work Schedule | Occupational Exposure--adverse effects. | Risk Factors

Classification: NLM W1

“Night shift work” involves work, including transmeridian travel, that occurs during the regular sleeping hours of the general population. This alters exposure to the natural light–dark schedule and disrupts circadian rhythms.

About the cover: the image depicts night shift workers performing maintenance on a railway track.

Source: ©dissolve.com/Cultura

How to cite: IARC (2020). Night shift work. IARC Monogr Identif Carcinog Hazards Hum, 124:1–371.