This blog focuses on current issues surrounding workplace injuries and illnesses


Popcorn lung sounds like it might not be so bad, but don’t let the name fool you.

In the microwave popcorn industry, significant amounts of flavorings are often used to ensure the treat has a delicious and buttery flavor.  You may think that BMI is where we are headed with this, but in fact diacetyl is our concern today.  Diacetyl occurs naturally in alcoholic beverages, dairy products, and coffee, and is the chemical used to give microwave popcorn a buttery flavor.

Diacetyl exposure first came to public attention when eight former employees of the Gilster-Mary Lee popcorn plant in Missouri developed bronchiolitis obliterans.

Bronchiolitis obliterans is an inflammatory obstruction of the lung's tiniest airways (see above) and can lead to respiratory failure.  Bronchiolitis obliterans is a mouthful (no pun intended), and was therefore coined the charming “popcorn lung.”

In 2000, the Missouri Department of Health called in NIOSH to recommend safety measures in the case of the eight workers exposed to diacetyl.

Diacetyl has been shown to cause epithelial damage that can lead to obliterative bronchiolitis in workers exposed to it during the production of microwave popcorn, flavorings, and other foods such as cookie dough and pet food.  (The related chemical, 2,3-pentanedione, a diacetyl substitute, has proved no less hazardous.)

In 2007 a Denver man was awarded $7.2 million in a
lawsuit against a popcorn maker and a grocery store
after getting popcorn lung from microwave popcorn. 
He had eaten 2 bags of popcorn a day for 10 years.
(Fulton 2012)

Now that we’ve ruined home movie night, let’s expand the scope of “popcorn lung” by looking at another source of diacetyl: coffee.  Most American adults (54%) drink coffee every day*, and a study published in the August 2015 Toxicology Reports by Gaffney et al found high levels of diacetyl and 2,3-pentanedione in the air at a small coffee roasting plant.

They conducted sampling of three roasting batches and three grinding batches at varying distances from a commercial roaster and grinder.  Interestingly, the diketone concentrations were higher during grinding than those measured during roasting. 

The results indicate that airborne concentrations of naturally occurring diacetyl and 2,3-pentanedione are associated with unflavored coffee processing.  These results are similar to the concentrations that have been measured in food flavoring facilities (like microwave popcorn factories), and are likely to exceed the recommended short-term occupational exposure limits.  In this study the analyses of exposure were found to be lower than concentrations that would cause responses in the human respiratory tract, but when compared with the exposure limits suggested by NIOSH for diacetyl in popcorn, are well above safe standards. 

Pierce et al (2015), simulating a cafe setting, found the potential for risk to customers who stay in coffee shops for hours.  Samples were collected while a barista ground whole coffee beans, and brewed cups of coffee for customers.  The mean estimated exposures for the barista exceeded recommended eight hour occupational exposure limits for diacetyl and were comparable to measurements collected in various food and beverage production facilities.

Based on area sampling, the parts per million exceedances of the recommended occupational exposure limit may also occur for coffee shop workers who do not personally prepare coffee, but work near the process (and the customers socializing or lingering on their laptops).

Duling et al (2016) found bronchiolitis obliterans in five former coffee processing employees at a single workplace.  This prompted a NIOSH exposure study of current workers.  Exposure characterization was performed by: observing work processes, assessing the ventilation system and pressure relationships, analyzing headspace of flavoring samples, collecting and analyzing personal breathing zone, and area air samples by work area and job title.  Workers in the unflavored coffee grinding/packaging area had the highest mean diacetyl exposures, and 2,3-pentanedione exposures were highest in the flavoring room.

In honor of our apparent aim to poop on your party, keep an eye out for the roll that diacetyl plays not only in popcorn and coffee (and cookie dough and dog food), but also in the ever-controversial e-cig industry (Dr. Schumpert has a whole soap box about this one, so stay tuned). 

A quick stop for a cuppa, a handful of buttery popcorn from a bag, or the passing whiff of an e-cig will not (I repeat, NOT) make your lungs look like this:

But, next time you plan to spend the day in a coffee shop, we recommend you find a well-ventilated seat by the door. 


Diacetyl is an organic compound with the chemical formula (CH₃CO)₂. It is a yellow/green liquid with an intensely buttery flavor.

A Diketone is a molecule containing two ketone groups. The most simple diketone is diacetyl.

Epithelium is one of the four basic types of animal tissue.  These tissues line the cavities and surfaces of blood vessels and organs throughout the body (including the lungs).


·        Jennifer S. Piercea, Anders Abelmann, Jason T. Lotter, Chris Comerford, Kara Keeton, Brent L. Finley. Toxicology Reports 2 (2015) 1200–1208.

·        Shannon H. Gaffney, Anders Abelmann, Jennifer S. Pierce, Meghan E. Glynn, John L. Henshaw, Lauren A. McCarthy, Jason T. Lotter, Monty Liong, Brent L. Finley.  Toxicology Reports 2 (2015) 1171–1181.

·        Matthew G. Duling, Ryan F. LeBouf, Jean M. Cox-Ganser, Kathleen Kreiss, Stephen B. Martin Jr., Rachel L. Bailey.  Journal of Occupational and Environmental Hygiene (2016).

·        Image:

·        *




Here at REOH, heels are optional (but not absent)


"Ms. Thorp...helped spur a popular revolt in Britain after she started a petition calling for a law that would prevent women from having to suffer from what she considered outdated and sexist dress codes at the office. In her case, she had been told that her shoes needed to be a minimum of two inches high."

Woman's revolt against high heels - NYTimes

And she succeeded.  We thought this one was an interesting side note to work place safety, although the point is more about freedom and respect.  We got curious about how, exactly, heels affect the musculoskeletal systems (yes, we are nerds, but you already knew that).  If you are curious too, here is what we found.  It isn't looking good for Anya and her shoe collection.

The risks include:
1. Damage Toe Nails (L60.0)
2. Worsen Bunions (M21.61)
3. Increase Knee and Hip Pain (M25.569 & M25.559)
4. Increase Your Risk of Osteoarthritis (M15-M19)
5. Muscle Pain and Spasms (780.96 & 728.85)
                                                        More at

"There are ways to minimize the risk of injury.
Stretching - To stretch lower leg muscles, use a towel to pull your foot towards you for 30 seconds.
Strengthening - Use a theraband to strengthen the big muscles of the lower leg and ankle. Use the theraband to resist the ankle as it pushes up, out and in
Standing toe raises - To work the smaller muscles of the leg, put small objects on the floor and use your toes to pick them up.
Balance - Stand on one limb at a time, holding position for 30 seconds."
                                                     More at

Some high heel stats

And...strangely enough, there is no ICD-10 code for injury by high heels, they do cover cleats and heelies (rolling shoes) though.

I'd rather have a sprained knee than suffocate::  22 February 2017

This excerpt caught our eye, it is definitely worth a look at the article!

"'Animal-drawn vehicle accident' diagnoses (which include riding an animal) are disproportionately common in five states: Idaho, Montana, Wyoming, North Dakota, and Nebraska. Surprisingly, there were nearly 43,000 'animal-drawn vehicle accidents' in our national data from 2012 to 2016."

more at:

UH OH!  ::  26 May 2016

cell phone

In breaking news this week, we found this in our inbox from the University of North Carolina:
A public announcement from The National Toxicology Program is expected soon about a study recently completed on rats that links cell phone use to cancer risk in humans. The study showed significant increases in cancer in rats that were exposed to cell phone signals for two-years.  Federal agencies are trying to determine the best way to inform the public about this danger that could effect so many Americans (according to the Pew Research Center, 90% of American adults own a cell phone).

More details at
Or if you are really ambitious, read the study,

DEAR DOC  ::  22 April 2016

Dear Doc,

"I have been hearing conflicting information about what causes carpal tunnel syndrome.  Can you clarify the primary causes of this occupational disease?"
                                                                      - Curious in Great Falls

Dear Curious in Great Falls,

This is a great question and an extensive amount of research has been conducted about the causes of carpal tunnel syndrome, both from workplace stressors and predisposition. 

Common symptoms exhibited by someone with this syndrome include:  numbness and tingling in the fingers (primarily on the palm side), numbness and tingling that awakens one from sleep, and a weakness in grasping objects.

According to studies* the work-related causes of carpal tunnel syndrome include: repeated use of vibrating hand tools and work that requires forceful and repetitive grasping of objects.  Notably this list does not include typing at a keyboard or data-entry, which is a common misconception about carpal tunnel syndrome.

It can also be caused by non-work related factors such as: obesity, hypothyroidism, rheumatoid arthritis, fluid retention from pregnancy and menopause, or simply having a smaller tunnel (this is why women are three times more likely to be affected).

Wondering what the heck a carpal tunnel is, and how it becomes a “syndrome?”  Check out this link

An example of a scenario in which I have seen a worker with job-related carpal tunnel syndrome was a man who had worked as an industrial electrician for 30 years.  He used vibrating tools regularly and had to twist his wrist while applying pressure when working on control panels on a daily basis.  Although he did have a history of hypothyroidism, he had no other non-work related factors and I concluded that his injury was work related.

On the other side of the spectrum was a woman employed in retail.  Her work-related tasks included some lifting and cutting, customer service, answering phones, and computer work (i.e. keyboard and mouse).  She complained of numbness, burning, and weakness and pain in her hands, wrist and forearm.  Her electrodiagnostic studies demonstrated a moderate bilateral carpal tunnel syndrome.  However, when reviewing her records and medical history it was clear she had a history of obesity and inactivity.  I determined that this particular case was not work-related but instead due to predispositions to the syndrome.

What treatments can help carpal tunnel syndrome?  I generally recommend non-surgical methods to start which include: a wrist splint (especially at night); additional intake of vitamin B6; an ergonomic workstation; frequent rests; avoiding or limiting positions that include the risk factors listed above; and occupational therapy to learn tendon gliding exercises.  If symptoms do not improve within a few months, a visit with a physician about whether a carpal tunnel release is necessary would be appropriate.

Carpal tunnel syndrome can be prevented proactively in the workplace by implementing breaks, ergonomic tools and positions, and stretching.
                                                                      - The Doc

Further reading:

If you want to know more about how carpal tunnel is diagnosed, here are some links that explain a few of the tests we use during a physical exam to determine whether an injured employee is suffering from carpal tunnel syndrome:

·      Tinel’s and Phalen’s tests
·      Upper extremity nerve conduction studies


·      Mediouni Z, Bodin J, Dale AM, Herquelot E, Carton M, Leclerc A, Fouquet N, Dumontier C, Roquelaure Y, Evanoff BA and Descatha A. Carpal tunnel syndrome and computer exposure at work in two large complementary cohorts. BMJ Open2015;5:e008156.

·      Werner RA, Franzblau A, Albers JW, Armstrong TJ. Influence of body mass index and work activity on the prevalence of median mononeuropathy at the wrist.  Occup Environ Med. 1997 Apr;54(4):268-71.

·      El-Salem K, Ammari F. Neurophysiological changes in neurologically asymptomatic hypothyroid patients: a prospective cohort study. J Clin Neurophysiol. 2006 Dec;23(6):568-72.

·      Hou WH, Hsu JH, Lin CH, Liang HW. Carpal tunnel syndrome in male visual display terminal (VDT) workers. Am J Ind Med. 2007 Jan;50(1):1-7.

·      Lewańska M, Wagrowska-Koski E, Walusiak-Skorupa J. [Etiological factors for developing carpal tunnel syndrome in people who work with computers]. Med Pr. 2013;64(1):37-45.

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