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New Study Highlights Potential Diacetyl Risk to Restaurant Workers

Posted to the IUF website 03-Jan-2008

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A study commissioned by the US daily newspaper Seattle Post-Intelligencer shows that restaurant workers could face serious potential health risks stemming from exposure to the flavouring ingredient diacetyl. Diacetyl, a food flavouring chemical in artificial butter flavours, is a common ingredient in the margarines, shortenings and cooking oils and sprays used in commercial kitchens. Chemically derived diacetyl is even added to all unsalted butter in the US. Heated for cooking, these ingredients release vapours which could place workers at risk of developing the debilitating, potentially fatal lung disease bronchiolitis obliterans which has affected workers exposed to diacetyl in the food processing industry.

According to Dr. Richard Kanwal of the National Institute for Occupational Safety and Health (NIOSH), "It is possible that the amount of diacetyl being released in commercial kitchens where these butter-flavored products are being used could equal or perhaps exceed what was found in the popcorn plants."

The laboratory study, which measured air samples released from a heated kitchen skillet using a variety of commercial products containing diacetyl, detected diacetyl levels of 7 to 16 parts per million (ppm) in the vapours released by two butter samples, 7 to 180 ppm in the margarine and shortening products tested, 164 ppm in a butter flavoured cooking spray, and 23 to 234 ppm in butter flavoured cooking oils. Oils used for popping corn (as high as 1,125 ppm) produced the highest levels. Cooking products containing diacetyl have never been tested in a commercial kitchen, where conditions vary widely with regard to the use and distribution of ventilators, positioning of stoves/burners etc.

Following on political pressure for regulatory action from US unions in response to the mounting toll of lung damage among food processing workers, the newspaper's study has added to the pressure for legislative and food industry action. The IUF-affiliated UNITE-HERE, representing kitchen workers in restaurants, hotels and catering, responded to publication of the study results with a call for action stating that "It is completely unacceptable that working cooks should have to put their lungs at risk just to complete a day's orders."

ConAgra, makers of the cooking spray PAM (one of the products tested), responding by declaring that it plans "to have all PAM products containing diacetyl off store shelves by next month." However, scientists who took part in the research estimate that diacetyl is used in some 6,000 commercial products in the US. The IUF is not aware of any comparable estimates for the rest of the world. Regulatory authorities in the European Union, for example, acknowledge that the product is extensively used in processed foods, but have been content to reiterate that diacetyl has been declared safe...for human consumption. The problem remains that the potential risks facing food processing and kitchen workers have never been properly investigated despite mounting evidence that diacetyl exposure can lead to serious illness and even death.