Following reports that scientists at the United States Department of Agriculture are being harrassed and their research on bee-killing pesticides is being censored or suppressed, a broad coalition of farmers, environmentalists, fisheries and food-safety organizations urged an investigation in a May 5 letter sent to Phyllis K. Fong, USDA Inspector General.

"The possibility that the USDA is prioritizing the interests of the chemical industry over those of the American public is unacceptable," states the letter, which was signed by more than 25 citizens' groups concerned that a forthcoming report by the White House Task Force on Pollinator Health, which is co-chaired by the USDA, will be compromised.

The signatories include the American Bird Conservancy, Avaaz, Center for Biological Diversity, Center for Food Safety, Farmworkers Association of Florida, Food and Water Watch, Friends of the Earth, Green America, Organic Consumers Association and Sierra Club.

"It is imperative that the American people can trust that their government and its employees are serving their constituents and not the profits of private companies," they wrote. "All of the research that the USDA conducts must maintain scientific integrity and transparency to ensure it is guiding sound policy decisions."

The research in question centers on neonicotinoids, a nicotine-like class of insecticides that impair the neurological systems of insects and which studies have linked to die-offs of bees and monarch butterflies—two key pollinators—as well as birds. Neonicotinoids have been strongly linked to honey-bee colony collapse disorder (CCD), a syndrome first observed in Germany that has been blamed for massive bee population declines across the globe. In 2013, certain neonicotinoids were banned by the European Union and a few non-EU nations.

The global food system relies on bees to pollinate at least 30 percent of the world's crops. Bees are responsible for pollinating a host of American crops, from apples and almonds to cantaloupes and cucumbers, impacting $15 billion a year in U.S. crops.

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In March, Public Employees for Environmental Responsibility (PEER), an environmental activist group supporting local, state and federal researchers, filed a legal petition with the USDA seeking new rules meant to increase the job protection for government scientists and citing censorship and harassment. At least 10 USDA scientists have come under fire for research into farm chemical safety that conflicts with the interests of the agribusiness sector, according to PEER executive director Jeff Ruch.

"They have very little in the way of legal rights and have career paths that are extremely vulnerable," he said. He said the scientific work under scrutiny is the research into the effects of neonicotinoids and glyphosate, the key ingredient in Monsanto's popular Roundup herbicide, which the World Health Organization recently concluded likely causes cancer.

"Your words are changed, your papers are censored or edited or you are not allowed to submit them at all," a senior scientist at the USDA's Agricultural Research Service told Reuters.

“Censorship and harassment poison good science and good policy,” said Lori Ann Burd, environmental health director at the Center for Biological Diversity. "There’s no question that neonicotinoids are killing bees, and it’s long past time for our government to take action. The European Union has already banned neonicotinoids. The reports that USDA is harassing and suppressing its scientists for doing their jobs instead of using their findings to protect our pollinators are extremely disturbing."

“How can the American public expect USDA to develop a federal strategy that will protect bees instead of pesticide industry profits if it is harassing and suppressing its own scientists for conducting research that runs counter to industry claims?" said Tiffany Finck-Haynes, food futures campaigner with Friends of the Earth.

In April 2014, the group released “Follow the Honey: 7 ways pesticide companies are spinning the bee crisis to protect profits,” a report documenting the deceptive tactics used by agrochemical companies to deflect blame from their chemicals to pollinator declines and stall governmental regulation on neonicotinoids. The companies named in the report include U.S.-based Monsanto, Switzerland-based Syngenta and Germany-based Bayer, which patented the first commercial neonicotinoid, Imidacloprid, the world's most widely used insecticide.

"If USDA wants to employ a kill-the-messenger approach," said Finck-Haynes, "it will only delay critical action to address the bee crisis that threatens our nation’s food supply."