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The late 1890s and early part of the 20th century were characterized
by rapid industrialization, with a huge growth in low-wage factory jobs.
These factories were incredibly unsafe: employees working with
dangerous chemicals could expect to come home covered in them,
and people were even locked into their places of work.
And these jobs came with illnesses and conditions that were considered
unavoidable occupational risks.
But if you wanted your children to eat, you’d take those risks.
Enter Dr. Alice Hamilton, who asked: how can we mitigate those risks
to keep people safe and healthy at work?
Alice Hamilton was born in 1869, which you may recognize
as a time with very few women represented in medicine.
But Alice had made up her mind when she was a teenager
that that’s what she wanted to do.
So after taking lots of extra anatomy classes, and sweet-talking
her father into letting her go, she enrolled at
University of Michigan’s medical school and got her MD.
After doing her residencies, she decided that she’d rather do research
than open a practice, so she went to Germany to study bacteriology.
And there, she had to agree to make herself invisible in order to
attend lectures, a process involving a lot of sneaking into seats
that were carefully hidden in the backs of lecture halls.
And after coming back to the US, she lived and worked at Chicago’s
Hull-House, a so-called “social settlement” where recent immigrants
could receive services like healthcare and language classes.
Alice ended up treating many of the members of the community
for injuries and conditions they sustained on the job.
She credited her time at Hull-House as one of the main reasons
she started researching what were then called industrial diseases.
So she turned her medical and scientific training to the issue
of making these workplaces safer, starting with her own.
In 1905, she published a paper on the transmission of scarlet fever
and similar diseases in hospital settings, and made some findings
that are especially salient today.
She had a group of patients with scarlet fever cough, cry,
and breathe over a set of petri dishes, and then incubated
the samples to see if Streptococcus pyogenes, the microbe
that causes scarlet fever, was present.
Which it absolutely was.
And she found that the best way to block it was simply to cover
the mouth and nose, because the vector for the disease
appeared to be saliva and respiratory droplets.
So she recommended that surgeons always wear masks when
performing surgery, because you could have scarlet fever,
but have yet to show symptoms.
This was a really important move in occupational safety for hospital
workers, but the results held true for any disease where
respiratory droplets can be a vector, making these findings
monumental for public health.
Among other research, her work is why mask-wearing caught on
as a way to reduce the spread of disease: first during
the 1918 Spanish flu, and more recently with things like SARS,
MERS, and…well, COVID-19.
While some of her early work was studying respiratory diseases,
Alice would really make a name for herself when it came
to industrial toxins.
She was hired to investigate lead, first by the State of Illinois
and later by the US Department of Labor.
Because lead was cheap and really easy to work with,
it was used in just about everything, like pipes, foil, and paint.
And the thing is, people already knew lead was toxic;
they just didn’t understand how.
We now believe that lead is poisonous because the body mistakes it
for calcium, which the body uses for bones and teeth, and in lots of
cell-signalling pathways controlling muscle and neuron function.
This means that lead concentrates in bones and teeth,
in nerves, and in the brain.
And when lead deposits in bone rather than immediately gumming up
the works in your brain and muscles, then you’ve got a super fun
lead reserve in your body that can be slowly released
long after exposure.
So at the time Alice Hamilton was beginning her research,
you’d see a wide variety of symptoms in folks who worked with lead,
and the onset and development of those symptoms didn’t always
coincide with exposure.
Which made it difficult to pin down lead as the source
of these illnesses -- and the owners of these factories
were perfectly happy with that, blaming symptoms on alcohol use
or poor hygiene.
But Dr. Hamilton proved them both wrong... and very liable.
In order to gather her data, she basically had to become
an investigative reporter.
She’d slip into factories without the owners’ permission,
because the owners regularly lied about how much lead
they were using and how they used it.
She’d also take factory workers and union leaders out for beers
so they could speak freely, and had workers sneak her samples
of materials so she could test them for lead.
And she discovered over 70 industrial processes through which
workers were being poisoned and killed, leading to
major safety overhauls in the lead industry, as well as
the replacement of lead in stuff like paint and foil.
Her work made her the expert in occupational health,
so when Harvard began their industrial hygiene program,
they hired her on as an assistant professor.
She never got tenure -- you can maybe guess why -- but she did
negotiate for half of every year off to continue her field work.
And it’s because of her efforts that the United States
has organizations like OSHA and NIOSH, which create guidelines for
workplace safety and continue to research workplace health hazards.
So thanks to Alice Hamilton’s ingenious scientific mind
and unparalleled awesomeness, the world is a much safer place.
Thanks for watching this episode of SciShow,
and thanks to our patrons for helping to make it happen.
We really enjoy being able to tell stories about awesome
overlooked figures from history like this, and it’s your support
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