Eight cases of a rare and life-threatening form of lung disease have been discovered among those who worked in food flavouring plants in California between 2004 and 2007, a new study finds.
In addition, levels of lead are elevated among women who work in plants that make batteries, according to a second report in this week's issue of Morbidity and Mortality Weekly Report, a publication of the US Centres for Disease Control and Prevention.
Among food flavouring plant workers, a severe lung disease known as bronchiolitis obliterans appears to result from inhaling the chemical diacetyl, which has been known to cause the same problem among workers in the microwave popcorn industry.
"Bronchiolitis obliterans is a severe lung disease that can be prevented with appropriate measures, such as engineering controls, work practices, medical surveillance, and a respiratory protection programme," said report co-author Dr Rachael Bailey, an epidemic intelligence service officer at the CDC's National Institute for Occupational Safety and Health.
Diacetyl, which is used in butter flavouring, appears to be the culprit, Bailey said. "But there are literally thousands of chemicals that are used in making these flavourings and not all of them have been evaluated, so other chemicals may cause the disease as well," she noted.
Bronchiolitis obliterans is a rare disease, said Dr Richard Kanwal, a medical officer in CDC's National Institute for Occupational Safety and Health. "You don't expect to find this disease in the average worker," he said. "When we find this in a small workforce we get very concerned," he said. "One case is very rare, but when you find more than one in a workforce of 10 or 20 people, it is very striking."
Kanwal noted that there are no regulations that govern food flavouring plants. In addition, there are no regulations that govern the chemicals used in these plants. The CDC has asked manufacturers of food flavourings to take steps to create safer environments, including ventilation and respiratory protection for workers in these plants.
Bailey noted that an otherwise healthy flavouring worker who develops a cough or shortness of breath needs to be evaluated to see if the condition is work-related. "That person should be evaluated for bronchiolitis obliterans," she said.
More must be done
One expert agreed that more must be done to protect workers.
"Occupational lung disease is a hazard in many industries, from mining to farming to automotive work," said Dr David Katz, director of the Prevention Research Centre at Yale University School of Medicine. "These case reports suggest the need to add the food flavouring industry to the list, and to establish and enforce suitable safeguards so that workers are protected."
But the illnesses hint at something else of far greater importance to the public at large, Katz said. "If the chemicals used in the flavouring industry are this potentially dangerous to the workers handling them, how good an idea can it be for the rest of us to be eating them? Personally, I think artificial flavours should neither be inhaled, nor ingested," he said.
Risks in battery manufacturing
Another report focused on lead levels among women of childbearing age. The CDC researchers found that while lead levels for most of the 10 527 women tested in 10 states were low, there were elevated levels among some working women, particularly those engaged in battery manufacturing.
Women in that industry had 244 cases of blood lead levels above 25 milligrams per decilitre per every 100 000 women employed. That compares with 7.1 such cases per 100 000 women in manufacturing jobs, and 0.6 cases per 100 000 women working in all types of jobs.
In addition, the industry that includes battery manufacturing had a rate of 8.4 cases of blood lead levels above 40 milligrams per decilitre per 100 000 women employed in that industry, compared with rates of 0.4 per 100 000 employed in all of manufacturing and 0.04 per 100 000 employed in any job, according to the report.
"These higher rates suggest that despite the US Occupational Safety and Health Administration's recent focus on reducing workplace lead exposures among all US workers, the workplace remains a substantial source of exposure, and clinicians should consider work history when determining whether to measure blood lead levels," according to an editorial comment.
Public health implications
"The difference between blood lead levels that are considered elevated in females who are pregnant and those who might become pregnant has substantial public health implications," the editorial notes. "Identifying and counselling females of childbearing age who might become pregnant and expose children to lead in utero might help to prevent neurobehavioural and cognitive deficits."
Lead is a known neurotoxin, uniquely dangerous to the developing brain, Katz said. "Exposure during pregnancy is of special concern. The finding that work in the battery manufacturing industry appears to place women at increased risk of elevated blood level levels sounds an alarm," he said.
"Minimally, it means that women of childbearing age must be informed of this danger before hire. In many cases, however, a dangerous job may be more attractive than no job at all, so leaving avoidance of this threat to the individual woman is rather unfair. Ideally, working conditions will be altered to eliminate this threat at the source," he said. – (HealthDayNews)
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