Cranberry Bogs Are Serving Up Environmental Destruction

The cranberry PR machine has got it down: Widely viewed as a wholesome embodiment of the very joy and family togetherness of Thanksgiving, the tiny red fruits enjoy a reputation for being super-healthy (all those antioxidants! The miraculous power to destroy a UTI in one fell swoop!). And as one of only three fruits native to North America that are still commercially grown, they're also seen as patriotic. TV commercials from cranberry-growing giants such as Ocean Spray play up the berries' virtuous nature, hiring actors to portray friendly, befuddled cranberry farmers who lovingly cradle live turkeys and accidentally drop laptops into the bog. And those bogs! Dreamy waterways that glow crimson in the Massachusetts sunset, their calm stillness further suggesting a pure crop that integrates perfectly with the natural environment.

But as you load your plate with cranberry sauce on Thursday afternoon, consider that the reality of cranberries is far more insidious. Cranberry-growing conditions necessitate the use of high levels of chemicals—both fertilizers and pesticides—meaning that the fruits you ingest are potentially bad for you, and bad for the environment, as well.

"Cranberries are always on my list of fruit to buy organically, because the wet, boggy growing conditions of cranberries are conducive to weeds and pests," said Dr. Jessica Shade, director of science programs at the Organic Center, a nonprofit research organization in Washington, D.C. "This is especially true for cranberries: Because cranberries are native to North America, pathogenic fungi, parasitic weeds, and herbivorous insects have evolved alongside the fruit and have specialized to attack cranberries," she told me.

So while the watery bogs that cranberries grow in might look pristine, in reality conventional growers must add phosphorus-based fertilizers, as well as pesticides, in order to facilitate the fruit's output. And those chemicals don't just wash off the cranberries, but instead cling to the fruit even after harvest. In a 2008 report examining the levels of pesticides found on common fruits and vegetables, the Organic Center found cranberries to have the highest "Dietary Risk Index" of all the domestically grown fruits tested, meaning that the combination of the toxicity of the pesticides used on cranberries combined with the amount of chemical used was particularly high.

That's bad news for cranberry-eaters—many common pesticides have been proven to have carcinogenic or neurotoxic effects—but it may be even worse for the environment. At the end of each growing season, around October or November, water is pumped into cranberry bogs from nearby lakes and wetlands. This prevents the fruits from freezing and also causes them to float to the top of the water, which facilitates harvesting. Once the cranberries are harvested, the bog water—now laced with chemicals—is pumped through a series of ditches, dikes, and dams and discharged back into those local bodies of water.

One might assume that cranberry growers might be subject to governmental oversight, in the form of, say, the Clean Water Act, whose 1972 creation by the EPA was intended to help rehabilitate polluted American waters by regulating the discharges of common pollutants. But because of a loophole in the Act, cranberry bogs have historically been exempt from its reach, permitted to flush water that is by many accounts toxic back into nearby wetlands.

The semantics of the Clean Water Act are tricky, but the issue boils down to this: the original version, drafted in 1972, specified that growers of heavily irrigated crops such as cranberries and rice had to apply for permits regulating their operations. But in 1977, congressional amendments to the Act made no mention of the issue. According to the authors of a paper published in Lewis & Clark Law School's legal journal Environmental Law, "Congress's silence could be interpreted to exempt cranberry bog discharges from the permit program."

John Martin, an EPA press officer, confirmed this for me.

"That kind of agricultural runoff is not covered," he said. "If you have, say, a factory that's flushing wastewater, you do need a permit. But agriculture is not covered under that."

Cranberry producers have taken that exemption and run with it, to the detriment of waters surrounding cranberry bogs. Wisconsin is the nation's top cranberry producer, and last year harvested about 600 million pounds of fruit. But the state's waterways have shown evidence of strain.

"Several studies of northern Wisconsin lakes located downstream from areas of intense cranberry production showed increased levels of nutrients, particularly phosphorus, which contribute to harmful aquatic plant growth such as algae and weeds," the aforementioned authors write in Environmental Law. "One study showed that phosphorus releases from a cranberry bog exceeded that of a nearby residential housing development."

In addition to the effects of fertilizer, pesticide-laced water is a problem near cranberry bogs, too.

"One study in Wisconsin found that pesticide concentrations in surface water downstream from cranberry marsh discharges were sufficient to cause total mortality of two species of test organisms," the authors write. "Another study in Washington, also a leading cranberry producer, detected three toxic organophosphorus insecticides at lethal concentrations for aquatic invertebrates, exceeding that state's water quality criteria for aquatic life."

"We have to do the best we can to lessen that impact," said Carolyn DeMoranville, director of the Cranberry Station, a cranberry research center at UMass Amherst. In Massachusetts, the country's second-largest cranberry producer, farmers have cut their use of phosphorus-based fertilizers by about 50 percent in recent years, DeMoranville said. (Ocean Spray, the world's largest producer of cranberries, grows the majority of its fruit in Massachusetts, but did not comment on company practices for this article.)

"As far as pesticides go, growers do have to use pesticides," she said, but noted that the use of such chemicals is regulated under federal law.

So the next time you head to the fancy supermarket for a bladder's-burning home remedy, consider the bottle of organic cranberry juice. Or just crack a bottle of the standard stuff and enjoy the blissfulness of ignorance.