Canadian Occupational Safety

20 Canadian Occupational Safety www.cos-mag.com After extensive testing and many incorrect diagnoses, these workers were all diagnosed with obliterative bronchiolitis, the infl ammation, nar- rowing or obliteration of small airways (bronchioles) in the lung. The disease is uncommon, severe and irreversible. The majority of cases have limited or no response to medications. Five of the employees were on lung transplant waiting lists. The NIOSH investigation concluded that there was "a risk for occupational lung disease in workers with inhalation exposure to butter fl avouring chemi- cals." Further research also confi rmed exposure to diacetyl — the buttery-fl a- voured chemical in question — leads to decrease in pulmonary function. After a spate of headlines on "pop- corn lung," many popcorn brands, such as Orville Redenbacher, announced they would no longer be using diacetyl in their manufacturing processes. Many companies decided to use 2,3-pentanedione as a replacement for diacetyl, but researchers are sounding the alarm bells on this chemical, too. "2,3-Pentanedione it is a chemical that is similar to diacetyl… and we know from studies done in the lab with animals it is just as hazardous to the lungs as diacetyl," says Rachel Bailey, medical offi cer in NIOSH's respiratory health division. As a result, in October, NIOSH came out with recommended exposure limits for diacetyl and 2,3-pentane- dione. NIOSH is recommending an exposure limit of 5 parts per billion (ppb) for diacetyl as a time-weighted average (TWA) for up to eight hours per day during a 40-hour workweek. It is also recommending a short-term exposure limit for diacetyl of 25 ppb for a 15-minute time period. Additionally, NIOSH is recom- mending keeping exposure to 2,3-pentanedione below 9.3 ppb as an eight-hour TWA during a 40-hour workweek. NIOSH is also recom- mending a short-term exposure limit of 31 ppb during a 15-minute period. While the American Conference of Governmental Industrial Hygien- ists (ACGIH) already has an exposure limit for diacetyl — which has been adopted in British Columbia and Ontario — this is the fi rst time a limit has been recommended for 2,3-pentanedione. Both diacetyl and 2,3-pentanedione are not confi ned to just popcorn manu- facturing. They are both widely used as added fl avourings in food processing and manufacturing across the United States and Canada, and can be found in bakery products, such as cake mixes, fl ours and margarine; dairy products, such as cheese and yogurt; snack foods, such as cookies, chocolates, chips and crackers; beverages, such as soft drinks and alcoholic beverages; as well as candies, ice cream, puddings, chewing gum and frozen food. Both of these chemicals are mainly used as butter fl avouring but they are also used in the formulation of a number of other fl avours, such as cara- mel, hazelnut, vanilla and nearly any kind of fruit fl avour (including straw- berry, cranberry, grape and apple). Diacetyl and 2,3-pentanedione also occur naturally during coffee produc- tion and in the fermentation process of beer and Chardonnay. They also naturally occur in a variety of foods, such as butter, bread, milk products and chicken. According to NIOSH's Criteria for a Recommended Standard: Occupational Exposure to Diacetyl and 2,3-Pentanedione, obliterative bronchiolitis was confi rmed in diacetyl-exposed employees in at least eight fl avouring manufacturing plants, fi ve microwave popcorn plants, a diacetyl production plant, a cookie manufacturing plant and a coffee pro- duction plant. Workers who are at risk are those who work in the processing and manufacturing of these food products as well as those who work in chemical manufacturing — actually making the diacetyl and 2,3-pentanedione — as well as those who work in fl avour manufacturing — using diacetyl and 2,3-pentanedione to make fl avours that are then sold to food manufacturers. And it's not just the operators and front-line workers who face exposure: quality assurance personnel, labora- tory workers and supervisors may also be exposed. Maintenance workers are especially at risk because they are the closest to the equipment. According to the Flavor and Extract Manufacturers Association in the United States, the use of diace- tyl in U.S. food manufacturing is decreasing. In 2005, 228,00 pounds of diacetyl were used, compared to 85,000 in 2010. This is likely related to the increase in 2,3-pentanedione as a substitute, which had a reported poundage of 4,590 in 2005, compared to 38,000 in 2010. While Health Canada and the Fla- vour Manufacturers Association of Canada did confi rm usage of both diacetyl and 2,3-pentanedione in Canadian food processing and manu- facturing, neither had data on how much of these chemicals are actually used in this country. Companies using these artifi cial fl avouring agents run the gamut from small mom-and-pop shops to very large, multinational corporations, says Bailey. NEGATIVE EFFECTS One particularly alarming characteristic of obliterative bronchiolitis is the rapid onset and decline in lung function. "It's a concern for workers because you might damage yourself before you are even aware of it," says Brian Agnew, senior occupational hygiene and safety consultant at Pinchin in Waterloo, Ont. "(Whereas) some other things would be slowly developing and you might see decrease in lung function over a period of years or even decades." At one microwave popcorn plant, employees who had at least one day of experience mixing butter fl avourings into heated soybean oil had statisti- cally signifi cant higher prevalences of respiratory symptoms, compared to those who had never worked as mixers, according to NIOSH research. At a company that manufactured fl avourings for the baking industry, two production employees developed respiratory symptoms and severe fi xed airways obstruction within seven months of starting work at the plant. Aside from the restricted breathing symptoms, other symptoms of oblit- erative bronchiolitis may include fatigue, headache, fever, weight loss, night sweats, skin rashes and nausea. If a worker is exhibiting any of these symptoms, she needs to be removed from the exposure to be evaluated and to determine the cause of decreased lung function, says Bailey. "You want to get them away from the exposure as soon as possible so their lung function doesn't decrease any more. The more your lung func- tion deceases, the more disabling the disease is," she says. Workers should be encouraged to report any respiratory symptoms to their employer, she adds. One of the issues with obliterative bronchiolitis is it may be misdiag- nosed as other illnesses. None of the nine Missouri popcorn plant work- ers were initially diagnosed by their physicians as having obliterative bron- chiolitis. Initial diagnoses included pneumonia, asthma, emphysema, bronchitis, chronic obstructive pul- monary disease (COPD), hay fever and sinusitis. Asthma is one of the most common misdiagnosis, largely because the symptoms are similar and it's the most obvious choice. "Unless the physician knows the background of the worker and knows about the possible association between diacetyl and obliterative bronchiolitis, he or she may miss this and just simply think it's asthma," says Ian Wheeler, principal consultant at Certified Industrial Hygiene Consulting in Cal- gary. "Physicians have lots of things to think about and know about but their knowledge of industrial processes and chemicals is sometimes not as good as it might be, so they may not be able to put that association together." One clear way to distinguish between asthma and obliterative bronchiolitis is that with asthma, the coughing, wheezing and shortness of breath are exacerbated at work. For example, symptoms will improve on the weekends but get worse come Monday morning. This is not the case with obliterative bronchiolitis. The symptoms remain the same whether the worker is at work, home or on vacation, says Bailey. exposure to butter fl avouring chemi- cals." Further research also confi rmed exposure to diacetyl — the buttery-fl a- voured chemical in question — leads to decrease in pulmonary function. After a spate of headlines on "pop- corn lung," many popcorn brands, such as Orville Redenbacher, announced they would no longer be using diacetyl Many companies decided to use 2,3-pentanedione as a replacement for diacetyl, but researchers are sounding the alarm bells on this chemical, too. "2,3-Pentanedione it is a chemical that is similar to diacetyl… and we know from studies done in the lab with animals it is just as hazardous to the lungs as diacetyl," says Rachel Bailey, medical offi cer in NIOSH's As a result, in October, NIOSH came out with recommended exposure Both of these chemicals are mainly especially at risk because they are the airways obstruction within seven months of starting work at the plant. Aside from the restricted breathing symptoms, other symptoms of oblit- erative bronchiolitis may include fatigue, headache, fever, weight loss, night sweats, skin rashes and nausea. If a worker is exhibiting any of these symptoms, she needs to be removed from the exposure to be evaluated and to determine the cause of decreased lung function, says Bailey. "You want to get them away from the exposure as soon as possible so their lung function doesn't decrease any more. The more your lung func- tion deceases, the more disabling the disease is," she says. Workers should be encouraged to report any respiratory symptoms to their employer, she adds. One of the issues with obliterative bronchiolitis is it may be misdiag- S ubstitutes causing similar problems as the chemical they replaced is not a new phenomenon. In dry cleaning, for example, perchloroethylene (also known as tetrachlorethylene, PERC or PCE) is a solvent that has been in commercial use since the early 1900s. However, several expert agencies, including the International Agency for Research on Cancer and the United States' Environmental Protection Agency, determined PERC is likely a human carcinogen. It also causes: • mild loss of memory, visual perception and reaction time after several years of exposure • redness and blistering of the skin after prolonged dermal contact • dizziness, drowsiness and loss of co-ordination. Plus, PERC is very detrimental to the planet. Environment Canada has developed regulations to reduce the release of PERC from dry cleaning facilities. As a result, many dry cleaning companies started using 1-bromopropane as a replacement for PERC. But then this chemical was linked to neurological illnesses among exposed workers. Animal studies showed that 1-bromopropane may also cause cancer and reproductive disorders. Forward-thinking dry cleaning companies across Canada continue to search for the best alternative. HUNG OUT TO DRY

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