Occupational Health and
Occupational Medicine
David A. Compton MD, MPH
Work Related Disease Issues Have
Been Identified For A Long Time
• Hippocrates (460-377 BC)
– Described symptoms of lead poisoning among miners and
metallurgists.
• Pliny the Elder (23-70 AD)
– Roman senator who wrote about workers who protected
themselves from dust by tying animal bladders over their mouths.
– He also noted hazards of asbestos and cinnabar (mercury ore)
• Ulrich Ellenborg (1473)
– A German physician, he recognized the dangers of metal fumes,
described symptoms and preventive measures.
Influential People
• Paracelsus (1493-1541)
– Known by several names
• Born Phillip von Hohenheim
– A Swiss physician, he wrote a treatise on
occupational diseases
– Described lung diseases among miners and
attributed the cause to vapors and emanation from
metals
– Paracelsus is best known today as the “Father of
Toxicology” because of his observations of dose and
response:
“All substances are poisons; there is none which is not a
poison. The right dose differentiates a poison and a
remedy.”
Observant People
• Agricola (1494-1555)
– Born Georg Bauer, he was a physician appointed to
the mining town of Jochimstral in the Swiss
mountains
– Wrote De Re Metallica, a comprehensive discourse
addressing every aspect of mining, smelting and
refining.
– He noted the need to provide ventilation for miners,
and described “asthma” among workers who toiled in
dusty mines:
De Re Metallica
• “Some mines are so dry that they are entirely devoid of
water and this dryness causes the workmen even greater
harm, for the dust, which is stirred and beaten up by
digging, penetrates into the windpipe and lungs, and
produces difficulty in breathing and the disease the Greeks
call asthma. If the dust has corrosive qualities, it eats
away the lungs and implants consumption in the body. In
the Carpathian mountains women are found who have
married seven husbands, all of whom this terrible
consumption has carried off to a premature death.”
Perceptive People
• Bernardino Ramazzini (1633-1714)
– Italian physician, known as the “patron saint of
industrial medicine”.
– His book De Morbis Artificium Diatriba (The Diseases of
Workmen) described the symptoms of mercury and lead
poisoning and other occupational diseases.
– He wrote about the pathology of silicosis and
recommended precautions to avoid hazards
– Advised physicians to learn about occupational diseases
by studying the work environment, and exhorted them
to always ask their patients “Of what trade are you?”
Investigative People
• Sir George Baker (1722-1809)
– Discovered that “Devonshire colic” was caused by
lead contamination in cider.
• Percival Pott (1714-1788)
– A London physician, he was the first to link
occupational exposure to cancer.
• Scrotal cancer among chimney sweeps, caused by soot
• Later linked to Polycyclic Aromatic Hydrocarbons in Coal
Soot
• Sir Humphrey Davy (1788-1829)
– Investigated problems of mine explosions and
developed the first miner’s safety lamp.
American People
• Dr. Alice Hamilton (1869-1970)
– First woman faculty member at Harvard
University (1919).
– A social activist who worked to improve
occupational health and safety.
– Her autobiography “Exploring the
Dangerous Trades” details her experiences
in the mines and mills across America
Tragedies Stimulated Change
• Workplace Disasters of the early 1900s led to outrage and
subsequently to legislation to protect workers
– The Triangle Shirtwaist Fire probably was the most
important event leading to the regulation of occupational
safety
– The Triangle Shirtwaist Company was a New York City
“sweatshop” where dozens of mostly young female
immigrant workers crowded together to cut and sew
shirtwaists
• Shirtwaists were a popular ladies garment of the time,
especially for working women
• Sweatshops workers are paid low wages as they work
excessively long hours in unsanitary and unsafe conditions
Triangle Shirtwaist Company
• 1911 - The Triangle Shirtwaist Company
Caught Fire
– 146 workers died from fire in the upper floors of this
“fireproof” building
• Fire exits were inadequate or locked to keep the
workers at their work stations
• Unable to flee, many victims jumped from the
windows to their deaths
• The tragedy led to 36 laws reforming the state labor
codes
I’ll Take Any Job That Pays…
• 1930 - Gauley Bridge Disaster
– Also known as the Hawks Nest tragedy, this was America’s
worst industrial disaster
– Construction of the Hawks Nest tunnel near Gauley Bridge,
West Virginia, caused massive exposures to silica dust
– At least 476 men died and 1500 disabled by silicosis. Silica
exposures were so high men were dying from acute
silicosis from only two months of exposure
– Pneumatic drilling equipment and rock high in silica
content magnified the risk
– Economic factors of the Great Depression forced the men
to work in unhealthy conditions
Everyday Tragedies
It took a tragedy to get attention, since death on the job was a normal every-day
event. In this single Pennsylvania county, 524 workers died in one year.
MMWR, June 11, 1999 / Vol. 48 / No. 22
Social Factors
• Organized Labor
– Labor unions did much to influence improvements in
workplace health and safety by influencing legislation as
well as forcing concessions from management.
– The International Ladies Garment Workers Union (ILGWU)
was established in1900 and took on the task of promoting
comprehensive safety and workers’ compensation laws
• Professional Organizations Were Formed
– American Society of Safety Engineers, 1911
– National Safety Council, 1913
– American Industrial Hygiene Association, 1939
What Changed?
• Other countries led the United States in adoption of workplace regulation
– Laws in Great Britain regulated conditions and limited child labor
• 1802 Factory Act
– Health and Morals of Apprentices Act, it established minimum
working conditions and regulated child labor
• 1833 Factory Act
– Further restricted child labor
• 1842 Mines Act
– Prohibited boys less than 10 years old and all females from
working underground. Before this act, children as young as 7
years were harnessed with chains to haul heavy coal containers
underground
• 1844 Factory Act
– Reduced work hours for children, extended coverage to women
US Laws and Regulations
• Early U.S. Laws and Regulations
– United States Bureau of Labor established in 1884 to study
employment and labor
– Laws and regulations to protect US workers first began to
appear in the early 1900s
– 1911- New York and New Jersey passed workmen’s
compensation laws.
– 1913 - New York State Department of Labor
– Established a Division of Industrial Hygiene
– 1916 - 1930 Forty-seven states enacted workmen’s
compensation laws to guarantee wages and medical care for
injured workers
More US Laws and Regulations
• 1935 - The Social Security Act
– Made funds available for public health programs.
• 1936 - The Walsh Healey Public Contracts Act
– Required organizations supplying goods or services to the U.S.
government to maintain a safe and healthful working environment
• 1948 - All states had workers compensation laws
• 1970 - The Occupational Safety and Health Act
• Established NIOSH and OSHA to carry out its mandate to ensure a
workplaces free of recognized hazards.
• 1977 - The Federal Mine Safety & Health Act
• Consolidated all federal health and safety regulations of the mining
industry, strengthened and expanded the rights of miners, established
the Mine Safety and Health Administration (MSHA).
What About Medical Care For Workers?
• By the 1930s, a medical specialty was formed:
Industrial Medicine
• Physicians in this area of practice were
generally self-taught or taught on the job until
the late 1940s when specialty training, testing,
and board certification were developed and
the resulting new specialty was renamed
Occupational Medicine
What Do Occupational Medicine
Practitioners Strive For In Daily
Practice?
“The highest degree of physical,
mental and social well-being of
workers in all occupations.”
International Labor Organization
Committee on Occupational Health, 1950
Occupational Medicine
• Recognized Specialty For
Over 50 Years, certification is
under the American Board
of Preventive Medicine
• Combines Clinical Skills
With Toxicology,
Epidemiology, Safety,
Rehabilitation, and Business
Operations
• “Tightrope Walker”
Responsible to Patients,
Business, and the
Community
Occupational Health Services
• Detecting, Evaluating, and
Treating Medical
Conditions
• Emergency Response
• Medical Surveillance
• Chronic Disease
Management
• Fitness and Wellness
• Work-Life Management
• Disability Management
and Accommodation
• Employee Assistance and
Advocacy
• Absence Management
• Training
• Consultant to Workers,
Managers, Unions, and
the Community
Why a Special Practice Model?
• Occupational Diseases are Hard to
Distinguish From Ones Unrelated to
the Workplace
• Absences from Work Have Multiple
Causes (not all are medical)
• Economic Implications of Maintaining
a Healthy Workforce are Large
Source: USA Today
Since It Is Hard To Differentiate
Occupational Diseases From
Naturally Occurring Diseases,
How Do You Know For Sure That
The Disorder Is Or Is Not
Associated To The Work
Environment Or Activities?
Important Considerations When Considering
Linkage Of A Disease To Work Activities
• Strength of association - The greater the impact of an
exposure on the occurrence or development of a disease, the
stronger the likelihood of a causal relationship - dependent on
epidemiologic and/or toxicological data
• Consistency - Do all of the research reports have similar
conclusions?
• Specificity - Has it been shown that exposure to a specific risk
factor results in a clearly defined pattern of disease or
diseases?
• Temporality or time sequence - Did the exposure precede the
disease by a period of time consistent with proposed
biological mechanisms?
More Considerations For Occupational
Disease Linkage
Biological gradient - Has it been shown that the greater the
level and duration of exposure, the greater the severity of
diseases or their incidence?
Biological plausibility - Does it make biological sense to suggest
that exposure leads to the disease?
Coherence. Does review of the evidence lead to the conclusion
that there is a cause–effect relationship in a broad sense and
in terms of common sense?
Interventional studies. Have there been trials where removing
the hazard from the workplace eliminates the development of
the disease?
What Does It Mean To Have An Occupational
Health Program?
• The Goal is to Enable Employees to Safely Attend Work
and Successfully Perform Their Tasks Without Interference
from Health Based Issues. Thus, a successful occupational
health situation represents dynamic equilibrium between
the worker and his or her occupational environment.
• Health and safety consideration must be given to work
processes and how they impact employees, their contacts,
and the environment
• If an employee is absent (for any reason), occupational
health practitioners should facilitate receipt of effective
and efficient medical interventions with a goal of return to
work as soon as practicable
The 10,000 Foot View Of
Occupational Health
• Identification
Intervene and Treat
– recognition
– assessment
• Control
– eliminate
– manage
– personal protection
• Prevention
The 1000 Foot View of Occupational Health
• Awareness Of Potential Hazards
• Qualitative Assessment
– Exposure
– Health (Worker Eval)
• Hazard Judgment
Interventions
– Acceptable
– Unacceptable
– Uncertain
Medical
Engineering
Administrative
• Quantitative Assessment
– Exposure
– Health
• Risk communication
Employee Evaluations
• Medical evaluations of employees should be conducted as
prevention and health promotion sessions with special attention
to health factors related to the job or to known hazards. They
are NOT a substitute for controlling workplace hazards or using
personal protective equipment.
• Employers often view physical examinations, and purchase these
services, as a commodity where low cost wins out –but the
evaluations need to be so much more. . .
– Can The Employee Physically do the Job?
– Are There Medical Conditions Impacted by the Job’s Requirements?
– Can We Control The Conditions in the Worksite or are They Better
Controlled in the Employee?
– Are There Regulatory Mandates?
– What are Past Practices by This Employer and in Similar Industries?
If We Are To Intervene And Prevent, How Do We
Know What To Address?
• Remain vigilant for activity or incident trends, changes in
people, worksites, or regulatory requirements. When all
else fails - ask the workers
• Develop relationships with people who control workplace
change (engineers, supervisors, purchasing agents)
• Evaluate potential or suspected issues early
– Involve all stakeholders - management, safety, human
resources, industrial hygiene, engineering, and medical
personnel.
– Balance the individual’s rights and needs with the rights and
needs of the employer but injury and illness prevention is
paramount.
Example - Firefighters
•
•
A 2007 Harvard study: heart disease kills more on duty
firefighters than anything else (45% of on-duty deaths)
Epidemiologically, the majority of on-duty heart disease
deaths in firefighters appear to be precipitated by physical
and toxic factors
–
–
–
General reviews have shown that heart disease is less
prevalent in firefighters than the general public
However – this is work in adverse environments, wearing
cumbersome equipment, generating high levels of stress, and
involving exposure to chemical toxins that may aggravate
cardiac risk
Is this epidemiologic association plausible? Let’s look at
some data:
New England Journal of Medicine 2007;356:1207-15.
Firefighter Heart Disease
Comparisons of on duty time and activities to Off Duty Time
and Activities Revealed:
– Firefighters are 12 to 136 times more likely to die of
heart disease when putting out a fire.
– Firefighters are 3 to 14 times more likely to die of heart
disease while responding to an alarm.
– Firefighters are 2 to 10.5 times more likely to die of
heart disease while returning from an alarm.
– Firefighters are 3 to 7 times more likely to die of heart
disease during physical training.
What is The Occupational Medicine Response?
• Based on the study findings, the best approach is to work with
professional and volunteer (70% of firefighters) fire departments to
educate firefighters and the medical community about the special
issues involving firefighters and cardiac disease.
Specifically – work to implement:
– Wellness and fitness programs for firefighters and their families to reduce
heart disease risk factors
– Encourage adoption of a requirement for firefighters to undergo entrance
and annual medical examinations by a provider well-versed in the
requirements of firefighting
– Encourage implementation of an annual physical performance test for all
firefighters
– A general understanding that, if heart disease is diagnosed in a firefighter,
a very open and careful discussion must be undertaken in advising this
person whether it is safe to return to duty
NFPA [2003]. NFPA 1582: Standard on comprehensive occupational medical program for fire departments. Quincy, MA: National Fire Protection Association.
NFPA [2000]. NFPA 1583: Standard on health-related fitness programs for fire fighters. Quincy, MA: National Fire Protection Association.
Even If You Have A Successful Program Of Prevention
And Intervention, Employers Often Ask: “What About
These Absences?”
•
•
Absences happen. An important point to remember is that even
problem employees get sick.
Another important point is that each day an individual is out of work,
they may lost income and the employer may lose productivity or have
to hire a substitute
•
•
•
•
The medical providers must work within company policies, any regulatory
requirements, and applicable privacy rules to address both points.
Programs must use competent and objective personnel for case evaluation
and absence management.
Success occurs when you obtain optimum intervention for the individual
and coordinate their return with the worksite.
Providers are not through when the individual returns to work, they
should monitor outcomes and prevention efforts after full return to work.
Final Thoughts
• Occupational Medicine practice is rooted in
prevention. Workers who develop occupational
diseases or receive injuries in the workplace
represent a failure of prevention.
• Many places that have Occupational Medicine listed
as a service on their signage are frequently only
practicing Workers Compensation Medicine and have
little to offer in the way of prevention - know your
service providers.