Mini-symposium: The forgotten history of occupational epidemiology
Monday 6 October 2025, 14.00 – 15.30 Glow
Moderated by Rajen Naidoo
Introduction to the Mini-Symposium: The forgotten history of occupational epidemiology
Jason Glaser
What paleoepidemiology can offer to the study of occupational and environmental diseases
Michele A. Riva (presenter)
Sara Conti
Abstract
Objective: To explore how paleoepidemiological approaches – defined as the use of historical sources and early medical statistics to investigate patterns of health and disease in past populations – can provide insights into the relationship between work, environment, and health, using historical mortality data from early 1800s Milan as a case study.
Material and Methods: This contribution revisits the pioneering work of Giuseppe Ferrario (1802–1870), founder of the “Accademia Fisio-Medica-Statistica di Milano” and an early advocate of using parish death registers—including occupation—to study population health. Drawing on Ferrario’s methodology, a recent paleoepidemiological investigation analyzed more than 18,000 death records from Milan (1816–1822), coding age, sex, causes of death, and occupational status. This allowed us to examine the occupational and environmental determinants of mortality in an early 19th-century urban context.
Results: Preliminary findings confirm a strong correlation between certain occupations and specific causes of death. Among seamstresses, for example, 30% of deaths were attributed to tuberculosis, as compared to 22% among the other workers (p-value < .001). This pattern appears linked to confined working conditions. Other occupational clusters—such as artisans, innkeepers, and healthcare professionals—displayed recognizable mortality patterns. The analysis also revealed seasonal peaks in mortality, particularly during winter months, suggesting the interaction of occupational exposure with climatic factors. The availability of meteorological and economic variables further enabled an ecological analysis of health risks.
Conclusion: Paleoepidemiology offers a powerful lens to investigate occupational and environmental health in historical contexts, revealing patterns that remain relevant for contemporary research. By recovering and analyzing forgotten or underused data sources, it strengthens our ability to trace the long-term impact of work and environment on health – especially where modern records are lacking. The work of Giuseppe Ferrario exemplifies how early epidemiological practices can inform today’s efforts to understand and prevent occupational disease.
Work-related topics when the discipline of public health was emerging
Johanna Feary (presenter)
Abstract
Objective: To understand how work-related hazards contributed to the emergence of public health as a formal discipline.
Material and Methods: A review of historical literature was conducted and key conditions summarised.
Results: The industrial revolution of the 18th and 19th centuries transformed working conditions. Workers were exposed to hazardous conditions including physical and chemical dangers, exploitation (especially of children) and unsanitary conditions with subsequent development of respiratory (and other) occupational diseases. In the UK, lawyer Edwin Chadwick’s Health Report (1842) documented links between occupational factors, poverty and health and led to introduction of the Public Health Act 1848. Medical literature evolved from case reports into descriptive occupational cohorts, with convincing patterns even absent formal statistical tools. Such examples include pneumoconiosis, which was described in coal miners in the 16th century, but which by the 19th century had been linked to coal dust inhalation. Miners’ ‘phthisis’ was prevalent and likely represented silico-tuberculosis—two conditions that even now are difficult to disentangle. The high mortality amongst miners led to employment of some of the UK’s earliest occupational physicians. In the Sheffield cutlery factories, metal grinders developed “Grinder’s Asthma” – now known to be silicosis from high-speed grinding using sandstone or gritstone wheels – with high mortality from respiratory failure. In 1819, Sir Arnold Knight observed that almost no grinders lived beyond 50 years; subsequent analyses demonstrated their excess mortality compared to that of the general population. In 1832 Charles Thackrah identified ‘shoddy fever’ in textile workers who developed respiratory disease from inhalation of cotton and other dusts. Later called lyssinosis, perhaps mistakenly from ‘lyssa’, before being renamed byssinosis (from byssus from the fibres from which it arises).
Conclusion: Early observations of work-related lung disease laid the foundations for the plethora of occupational diseases more generally that we see today and the discipline of occupational medicine.
Brief biographies of leaders in early occupational epidemiology
Paul Blanc (presenter)
Abstract
Objective: The biographical details of leaders in the field can help retrieve key parts of the neglected history of occupational epidemiology.
Material and Methods: The history of occupational epidemiology was reviewed from a biomedical and a historiographic perspective. Persons were considered leaders in the field if they carried out investigations among working groups, identifying risk factors or interventions to prevent or ameliorate adverse health outcomes and whose work influenced practice and policy. Shared biographical attributes among these figures were explored for general insights they provide.
Results: The biographies of six persons spanning three centuries are considered: James Lind (1716–1794); Louis-René Villermé (1782–1863); Alice Hamilton (1869–1970); Austin Bradford Hill (1897-1991); Alice Stewart (1906–2002); Archie Cochrane (1909–1988). All made important contributions in occupational epidemiology. Lind’s work as a Naval physician concerned “sea scurvy,” a life-threatening occupational disease among sailors, carrying out what is arguably the first clinical trial for any disease. Villermé is a founder of modern demography whose work on the health of textile workers was central to his oeuvre. Hamilton’s survey research methods among rayon workers set a new benchmark. Hill, remembered for his work on smoking, started off studying industrial fatigue. Stewart’s work on clinical radiation exposure eclipses appreciation of her study of nuclear industry workers. Cochrane, closing the circle with Lind, is renowned for promoting clinical trials, but this was rooted in his experience in pneumoconiosis research. All championed marginalized populations, a shared link to occupational epidemiology.
Conclusion: Occupational epidemiology owes a great debt to these figures, whose contributions warrant an integrated consideration to inform our own work and our training of future practitioners in the field.
Funding: Supported in part by a National Library of Medicine Michael E. DeBakey Fellowship in the History of Medicine.
Sentinel occupational illness outbreaks from an historical perspective
Steven Ronsmans (presenter)
Abstract
Objective: Long before “occupational epidemiology” existed as a formal discipline, astute clinicians, workers or local observers reported unusual disease patterns in specific jobs. These early sentinel events—individual cases or clusters—often offered the first clues of workplace hazards. This talk revisits historical examples.
Methods: A historical review focusing on illustrative cases where such sentinel events initiated the recognition of an occupational aetiology.
Results: In 1775, British surgeon Percivall Pott noted a high incidence of scrotal cancer in young chimney sweeps and linked it to soot exposure—a landmark observation, widely considered the first formal identification of an occupational cancer. In the 1870s, German mine physicians Hesse and Harting reported lung cancer among Schneeberg miners, noting that locals were already familiar with the link of the illness to mining. Later, radon exposure was confirmed as the cause. In 1895, surgeon Ludwig Rehn described bladder cancer in three dye workers. The link with aromatic amines exposure was confirmed by animal experiments (Hueper, 1938) and epidemiological work by Robert Case (1954) in British dye workers¬—regarded as the prototype of a historical cohort study. Bramwell (1914) noted scleroderma in stonemasons but wrongly attributed it to “holding cold chisels”; the link to silica exposure was confirmed by Erasmus (1957) and others. A sarcoidosis cluster in fluorescent lamp workers led Hardy and Tabershaw (1947) to identify chronic beryllium disease. In 1977, concerns about infertility among pesticide workers prompted a NIOSH investigation, confirming azoospermia/oligospermia linked to dibromochloropropane exposure. More recently (2000), when eight cases of a rare lung disease (bronchiolitis obliterans) appeared in popcorn factory workers, a prompt plant-wide investigation identified diacetyl, a butter flavouring chemical, as the likely cause.
Conclusion: Observations by clinicians and workers have played —and continue to play—a pivotal role in identifying occupational hazards, often preceding confirmation through epidemiological research.
Remembering history to protect the health of workers
Rajen Naidoo (presenter)
Abstract
Recognising the relationship between work and health is as old has the documented history of work itself. From antiquity to the current day, various approaches have provided important insights into these relationships. This has allowed us to develop interventions to protect the health of workers.
Our symposium today set out to achieve the following objectives:
1. Raising awareness about how the history of occupational epidemiology is being lost.
2. Recognising that the history of occupational epidemiology provides an understanding of tools necessary for investigating new associations.
We emphasize how history and historiography – whether the documentation of sentinel cases, through to epidemiological investigations – creates the foundation for better understanding emerging diseases and their association with work. The historical methods used in unearthing these relationships present clinicians and occupational epidemiologists with tools to initiate sophisticated epidemiological research.
While in many instances the recognition of the association or the unearthing of the evidence relies on individuals, such as Lind, Villerme and Hamilton, the documentation of sentinel cases of scrotal cancer and liver cancers and the development of case-series of mesothelioma and bronchiolitis obliterans, show that the most basic epidemiological approaches remain essential tools. Important figures such as Hill and Cochrane, household names in epidemiology generally, are often forgotten as scientists who sharpened their scientific tools in the world of work and health. Similarly, much of modern public health has its roots in those early scientists investigating the relationship between occupational exposures and disease, and identifying interventions – the fundamental basis of public health.
Occupational epidemiologists are encouraged to investigate historically archived materials – not just from government based sources, but parish registers, employment records and autopsy databases. Engaging with these novel sources of evidence, epidemiologists will better understand relationships between old exposures and disease resurgence, but new exposures and potentially new outcomes.