Food

Leaked Memo Sheds Light on Mysterious Bee Die-Offs and Who's to Blame

The culprit may be a pesticide that the EPA has allowed on the market despite the fact that the company which makes the pesticide has failed to prove it is safe.

A new leaked memo from the EPA has the beekeeping world buzzing. Bad puns aside, the failure of the EPA to protect the environment -- in this case, bees -- jeopardizes beekeepers' ability to continue in their work. Beekeeper Tom Theobald, who exposed the leaked memo, says that beekeepers now lose 30 to 40 percent or more of their hives each year, and it takes two years to recover each one. Theobald has been a beekeeper in Boulder County, Colorado for 35 years, but now he says he's not sure he can continue. "I can't afford to subsidize this as a hobby. I'll fold the tent," he says. "Commercial beekeepers will work themselves to death," he continues, noting that it's only the passion and commitment of beekeepers that has staved off a complete collapse of the entire beekeeping industry this long.

The leaked EPA memo, dated November 2, 2010, focuses on Bayer CropScience's request to register (i.e. legalize) its pesticide clothianidin for use on mustard seed and cotton. Clothianidin was first registered in May 2003, but its registration was conditional on safety testing that the EPA said should be completed by December 2004. Only, as the latest memo points out, the study, when it was done (long after 2004), was inadequate in demonstrating that clothianidin does not pose a threat to honeybees. Unfortunately, with the EPA's failure to ensure clothianidin's safety before allowing its use on corn and canola, it fell to beekeepers to discover why their bees were dying, and how the EPA allowed clothianidin on the market.

For beekeepers like Theobald, the story starts in the 1990's. During the warm months of the year when flowers are blooming, honeybees forage for nectar and pollen, eating them and storing them for the winter. When all went well, the bees could successfully survive the winter on their stored honey and pollen. Prior to 1995, Theobald and other beekeepers in his area lost about two to five percent of their colonies each winter. In an extraordinarily bad winter, 10 percent of the colonies might not make it. Beginning in 1995, 20 to 30 percent of colonies began dying each winter. At the time, Theobald assumed the cause were varroa mites, a parasitic mite that attacks bees. The mites were first found in the U.S. in 1987, but they did not reach Boulder County, CO until 1995, the same year the winter losses of bees grew.

Looking back, Theobald wonders if the losses were really caused entirely by the mites, or if the pesticide imidacloprid played a role. Both imidacloprid and clothianidin are "neonicotinoids," a class of pesticides that has risen in popularity in the last fifteen years. Imidacloprid, the first of the neonicotinoids to be commercialized, was registered in the U.S. in 1994. Neonicotinoids attack the nervous system of insects. They are frequently used by treating seeds prior to planting. Then, once the plant grows, the pesticide spreads to all parts of the plant -- including the pollen. The hope is that only pests who try to feed on the plant will be killed, and beneficial insects will not be affected. Sadly, it appears that the bees never got that memo.

A beekeeper has little control over where his or her bees forage, and whether they choose to dine on plants treated with pesticides. (Recall the recent incident in Brooklyn in which bees took a liking to the bright red syrup at a nearby Maraschino cherry factory, gorging themselves until they turned bright red and produced honey colored with Red Dye No. 40.) The bees of Boulder have their choice of alfalfa, yellow sweet clover, wildflowers, and an awful lot of corn. While corn does not require bees for pollination, it produces large amounts of pollen when it tassels -- a bee feast! Corn pollen is no doubt a major source of food for bees across the entire U.S., as more acres are devoted to corn than to any other crop. And beginning in 2004, corn seed companies began selling seeds with five times the previously used dose of neonicotinoids.

About four years ago, Theobald saw his winter losses climb again, to 30 to 40 percent. It was around that time that a Pennsylvania beekeeper, David Hackenberg, lost two-thirds of his hives and began investigating. Ultimately, he identified and made public the problem now called Colony Collapse Disorder. Theobald recognized the symptoms described by Hackenberg as what he had observed in his own hives: the bees would mysteriously disappear, and the empty hive would go weeks without bees from other hives coming to rob all of the honey. "Normally," says Theobald, "that would be unheard of."

Beekeepers around the world who experienced the same mysterious problem began looking for causes, and they all came to the same conclusion: neonicotinoid pesticides were behind CCD. When Theobald checked his hives in the fall of 2006, he found that the brood nests (the area where larva are kept) were smaller than usual. He says they should have been the size of a basketball, but instead they were the size of a grapefruit. In 2007, he did a more thorough investigation and found many hives with no brood at all. That meant that, after the summer bees died off (as they usually do), there would be no winter bees to replace them and to keep the colony going throughout the winter.

It appeared that the queen had stopped laying eggs around mid-September, and the larva from eggs laid before were dying. In early November, the queens began laying eggs once again. Theobald suspected that contaminated corn pollen, collected in August and stored, would have been fed to the larva and to the queen (as royal jelly) when the number of flowers declined and the bees needed to use their stored pollen, around mid-September. The contaminated pollen would have killed the larva and caused the queen to stop laying. With no bees to carry the hive through the winter (or a few bees, who might not survive), the entire colony dies.

With similar findings, some countries, like France, Germany, and Italy, banned or restricted the use of neonicotinoids. The U.S. did no such thing. In fact, as beekeepers questioned the safety of clothianidin, a neonicotinoid registered in 2003, the Bush EPA stonewalled and refused to provide Bayer's study demonstrating the safety of clothianidin to bees, even after a Freedom of Information Act (FOIA) request. In 2008, the Natural Resources Defense Council (NRDC) sued over the EPA's failure to comply with the FOIA. Around the same time, Theobald made an amazing discovery on the internet.

Theobald found the missing study, along with incriminating EPA memos showing their mishandling of clothianidin's registration. The first memo, dated February 20, 2003, says, "Considering the toxicity profile and reported incidents of other neonicotinoids (e.g. imidacloprid), the proposed seed treatment with clothianidin has the potential for toxic risk to honey bees, as well as other pollinators." The scientists recommended requiring a study that spanned the entire life of a worker bee to test clothianidin for toxicity to the workers (as well as to the queen) prior to allowing the product on the market.

Two months later, on April 10, 2003, the EPA scientists amended their request (presumably after their first request was denied), calling for the registration of clothianidin on the condition that the study was completed soon thereafter. In May, the EPA granted the conditional registration. In March 2004, Bayer requested an extension for the study, which was granted. However, the new May 2005 deadline passed and the study was not submitted. Bayer also requested -- and was granted -- permission to perform its study in Canada on canola (a minor crop in the U.S.), with no test performed on corn.

Bayer finally completed its study and submitted it to the EPA in August 2006. The EPA left the study to collect dust until November 16, 2007, when they reviewed it and deemed it acceptable. Thus, clothianidin's registration was finally complete. Eight months later, Theobald found the study online. In an article he wrote for Bee Culture, he summarized it as follows: "Here's what the life cycle study of bees and canola consisted of: four colonies of bees were set in the middle of one hectare (2 1/2 acres) of canola planted from treated seed, with the bees free to forage over thousands of surrounding acres in bloom with untreated canola, which they most surely did. What do you think the results were? They were exactly what Bayer wanted of course."

This past November, when Bayer CropScience requested the registration of clothianidin for use on mustard seed and cotton, the Obama EPA reviewed the earlier study and found in inadequate to justify the new registration, but made no comment about the existing registration for corn and canola. Beekeepers are enraged. If the study -- used to justify the legal use of clothianidin on corn and canola -- is insufficient, then there is no evidence whatsoever to demonstrate that clothianidin is not a significant threat to bees. Why is clothianidin still legal? The sloppy, if not corrupt, work by the EPA resulted in eight growing seasons (so far) of widespread use of clothianidin. As of 2007, for example, 80 percent of corn seed sold by market leader Pioneer Hi-Bred (DuPont) contained either 0.25 or 1.25 mg per seed of clothianidin.

For beekeepers, hopefully the discovery of the recent memo will lead to restrictions or a ban on use of neonicotinoids, at least until more reliable experiments are conducted to determine their effect on bees. The larger question, for all of us, is why the EPA allows pesticides on the market before they have been tested for safety (using conditional registrations), and how sound is the science -- conducted by the pesticide companies -- once it is done? "They just kind of put the pesticides out there and deal with the effects after they occur," says Maryam Heinen, who, along with George Langworthy, directed the new documentary Vanishing of the Bees.