News Coverage
Lettuce research no reason to skip salad, experts say
Published April 28, 2003
Don't pull that leaf of lettuce off your sandwich just yet.
A study released by a California environmental group about samples of lettuce from Northern California and Arizona that contained the chemical perchlorate, a hormone disrupter, had people talking Monday, but no stores were yanking lettuce off shelves.
Dr. Carl Winter, a food toxicologist with the FoodSafe program at the University of California-Davis, said the study is too small and too limited to draw any conclusions.
"This is a very preliminary, simple, non-controlled study, with motivations that go way beyond consumer safety," Winter said Monday.
The group, the Environmental Working Group of Oakland, has acknowledged that the study is small and has called for the federal government to conduct a study of perchlorate in the food supply.
Officials with the Food and Drug Administration said testing of food samples for perchlorate is planned.
Perchlorate, the explosive ingredient in rocket fuel, has been identified as a groundwater contaminant in the Southwest. In the lettuce study, the belief is that the lettuce was irrigated with water from the Colorado River.
Perchlorate in high doses can disrupt the thyroid gland. In pregnant women, that can affect hormone levels that control the development of the fetus, and in young children it could affect brain function and motor skills.
However, the amount of perchlorate that is acceptable in drinking water is under review by the U.S. Environmental Protection Agency.
In Charlotte, Jeff Lowrance, a spokesman for Food Lion, said that while the chain gets most of its lettuce from California, no specific growers were mentioned in the report. He said the chain is checking further to pinpoint more precise locations of its growers. (A Food Lion spokesman had initially said the company's lettuce originated on the East Coast.)
The Environmental Working Group declined to disclose the brands of lettuce that were contaminated, or where they had been purchased, saying it was wary of triggering a food scare.
But it said it had bought the lettuce at supermarkets in Northern California in January, when an estimated 88 percent of the nation's lettuce comes from farms nourished with water from the Colorado River.
Tara Stewart, a spokeswoman for Harris Teeter, said that chain's lettuce comes mostly from Central California's Salinas area, and Lowes Foods spokeswoman Diane Blancato said the company's lettuce is not coming from areas cited in the study.
A check of stores around Charlotte on Monday, including Harris Teeter, Bi-Lo and Food Lion, found that lettuce was not being removed from stores.
No government agency has suggested that lettuce supplies are unsafe.
A broker with a large lettuce supplier in West Virginia, who asked that his name not be used, noted the lettuce harvest moves north from Arizona through California through the winter.
Lettuce currently on the market comes from around Salinas, where farms don't pull water from the Colorado River.
Dr. Allen Jennings of the U.S. Department of Agriculture's Office of Pest Management said Monday that studies of perchlorate accumulation in food are under way.
He said the studies also include other vegetables grown throughout the Southwest. But that research hasn't produced enough data to draw any conclusions.
"Certainly, this time of year, when lettuce is coming out of Salinas, there isn't a problem," he said.
Winter, the food toxicologist, didn't doubt that perchlorate can be found in food samples, but he questioned the amount found in the lettuce. Environmental Working Group said it found perchlorate in four of 22 samples.
"In toxicology, the real question is how much is there," said Winter. "The first rule of toxicology is that the dose makes the poison. It's the amount of a chemical, not its presence or absence."
Winter said a wider study is needed. "There will be good, legitimate scientific debate about this."
In the meantime, he said, there's no reason not to continue eating lettuce and other fresh produce. "The best thing consumers can do is eat plenty of fruits and vegetables, including lettuce. The benefits of those things far outweigh theoretical concerns."
Consumers in the Charlotte area also have another alternative. Thanks to a long spell of rain and cool weather, stands at the Charlotte Regional Farmer's Market were piled high Saturday with local lettuce -- grown thousands of miles from California.