WINSTON-SALEM, N.C. - Green tobacco sickness, characterized by headache, nausea, vomiting and dizziness, may be increasing as family tobacco farms are consolidated into large commercial operations and work is done by migrant or seasonal farm workers, according to a Wake Forest University School of Medicine epidemiologist.
Writing in the current American Journal of Industrial Medicine, Sara A. Quandt, Ph.D., said that 41 percent of tobacco farm workers reported having green tobacco sickness at least once during the summer. Most are migrant Hispanic farm workers.
Quandt, associate professor of public health sciences (epidemiology), and four colleagues reported that the illness typically occurs after exposure to wet tobacco leaves in the morning while plants are still covered with dew, or after a rain. The disease is attributed to acute nicotine poisoning caused by contact with nicotine on the plants, which is rapidly absorbed through the skin.
"This is the first survey research to document green tobacco sickness as an occupational health risk among seasonal and migrant farm workers," Quandt reported.
While green tobacco sickness was first described in the medical literature in 1970, it rarely came to medical attention, perhaps because it was less likely to occur on small family tobacco farms, where exposure to wet tobacco leaves was limited.
"Instead of family groups with a few workers doing a relatively small amount of tobacco work, there are now hired, low-paid, usually minority workers working in tobacco almost exclusively for 8-12 weeks each year," Quandt said. "These workers are exposed to the risks of tobacco work for longer, more intensive periods of time than was ever the case for farming families."
Furthermore, she said, most of the migrants are from southern Mexico and are much shorter than the whites and African-Americans who used to work family tobacco farms. That difference in height may be critical during production when the flower is cut from the growing plants, usually 4-6 feet in height, to increase root growth, leaf weight and nicotine content.
"Absorption increases with the amount of skin exposed and with skin damage or disease," she said. Because the work is done on the hot, humid days of summer, workers are more likely to work shirtless.
The problem has been accentuated because production research has determined that spacing rows more closely together increases production poundage. That also increases the contact between the leaves and the skin. The harvesting of tobacco requires repeated trips through the field over a number of weeks, as the leaves are harvested from the bottom up.
While the symptoms of green tobacco sickness ordinarily include nausea, vomiting, and dizziness, she said there were no established diagnostic criteria yet. "Other frequently encountered symptoms include abdominal cramps, headache, breathing difficulty, pallor, increased sweating and salivation, chills and fluctuations in blood pressure or heart rate."
Most workers attempt to treat themselves. "Only 9 percent sought medical treatment," she said, "and 7 percent lost work time."
She added, "Many farm workers believe they will be fired and lose their income if they get sick or work too slowly. Green tobacco sickness is an environmental justice issue, part of the growing concern that poor, minority and medically underserved populations bear a disproportionate share of environmental and occupational health risks."
Quandt and other researchers at Wake Forest are now engaged in a three-year epidemiological study of green tobacco sickness among farm workers, financed by the National Institute of Occupational Health and Safety.
Contact: Robert Conn, Mark Wright or Jim Steele at (336) 716-4587.
Journal
American Journal of Industrial Medicine