Coffee Roasting and Popcorn Lung
Who among us coffee drinkers don’t love the smell of freshly roasted coffee? I am sure some of us imagine how much fun it would be to smell freshly roasting coffee more often. I don’t, because smell for me is an instant jolt of pleasure/pain followed by a rather rapid decline into the background.
Caution, though. New measurements from the US Centres for Disease Control warn of high exposure to some pretty nasty chemicals that can cause your lungs to be destroyed irreversibly, the unfortunately named “popcorn lung” or bronchitis obliterans:
Investigators with the National Institute of Occupational Safety and Health, a research arm of the CDC, spent several days at Madison-based Just Coffee in July. Investigators tested personal air space and took air samples to measure the concentration of the chemicals diacetyl and 2,3-pentanedione… NIOSH researchers found levels in three breathing-zone samples that exceeded the safety levels recommended by the CDC.
Coffee Roasting Plants and Exposure
The test results show a marginal exceedance in this case, but noted that ventilation is a big factor and these tests were done under well ventilated conditions on a warm and dry day when doors were open. So, exposure can be higher in other circumstances.
Worker exposures are to higher levels, and are more sustained, so they deserve the most attention.
So, local coffee roasters, it may make sense to confirm that your roasting environments are not exposing your workers to harmful, lung obliterating chemicals. Remember, organic, shade grown, fair pay, artisanal roasting aside, chemical exposures to workers don’t change. And, everything that smells good isn’t good for you.
One of my frequent points of emphasis (rants, some might say) is on the relative risk vs. media attention to exposures of people to ambient, day to day concentrations of potential harmful chemicals vs. those faced by workers everywhere. The last time diacetyl and bronchitis obliterans were in the news, it was around the use of diacetyl to produce that buttery smell so beloved in microwave bag popcorn (I don’t like it myself, olive oil all the way!). Despite reports of many workers facing severe lung issues, it took the detection of the disease of one person eating multiple bags of microwave popcorn over many years to actually move government regulators into action on diacetyl. People who work in factories, in the fields, and make things are exposed to thousands of times higher concentrations of harmful chemicals for longer periods of time, but their concerns are often de-emphasized.
This doesn’t mean ambient exposures in the general population are to be ignored, but worker exposures are to higher levels, and more sustained, so they deserve the most attention.
16-May-2016 Update
This US Centers for Disease Control page is a good collection of information and further readings. They recommend facility tests to measure diacetyl and its cousin 2,3-pentanedione, and better ventilation, worker safeguards and personal protective equipment as necessary. They also note that at least five workers in large scale coffee processing plants have been diagnosed with bronchitis obliterans.
Holy tentacular twins, Batman! This is crazy news, the first study linking the incidence of twins with environmental factors. The culprit is 
5 servings/wk) should limit intake of species highest in mercury levels. Levels of dioxins and polychlorinated biphenyls in fish are low, and potential carcinogenic and other effects are outweighed by potential benefits of fish intake and should have little impact on choices or consumption of seafood (women of childbearing age should consult regional advisories for locally caught freshwater fish).